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    Osteology abstract 202 cbct Osteology abstract 202 cbct Document Transcript

    • abStractbooKwww.osteology-cannes.org
    • PoSter abStractS oSteology foundation PoSter PreSentationTo promote the active scientific exchange the Osteology Foundation invited researchersand clinicians within the field of regenerative dentistry and dental tissue engineering tosubmit poster abstracts of original investigations for the Osteology Poster Presentation.We have invited the following six expert clinicians and researchers to participate in theposter abstract committee:Tord Berglundh, SwedenJean-Louis Giovannoli, FrancePaul Mariani, FranceFrancis Mora, FranceIsabella Rocchietta, ItalyEric Rompen, BelgiumThe poster committee evaluated more than 160 poster abstracts. The five best abstractsin each of the categories clinical research and basic research are invited to presenttheir work verbally to the poster committee.Osteology poster priceThe prize for the best poster in each of the two categories will be awarded on Friday,april 15, 2011 at 16.40 at the beginning of the Osteology Research Session.poster ExhibitionThe poster exhibition will take place in the exhibition hall.The accepted poster abstracts are subdivided into four different topics which can bedistinguished by the different numbering:Clinical research:Case Reports – 101, 102, 103,… (red)Clinical Studies – 201, 202, 203,… (green)Basic research:In Vitro Studies – 301, 302, 303,… (blue)Pre-Clinical Studies – 401, 402, 403,… (grey)The poster authors will be presenting their work on Friday, April 15, 2011 from 12.30 to13.45 and on Saturday, April 16, 2011 from 13.30 to 14.30.Pascal Valentini franck bonnet 27
    • Conclusions: Extensive loss of bone and teeth in the anterior maxilla presents CliNiCal rESEarCH, CaSE rEpOrTS a complex problem for reconstruction, especially in patients with severe bone loss in the horizontal and vertical planes. This technique is valuable for the reconstruction of severe bone loss. 101 i Secondary intention Surgical Wound Healing With Biomaterials in damaged Extraction Sockets 103 i using postauricular Split Thickness Skin Graft for Vestibuloplasty and prosthetic rehabilitation Of Fibula Free Emanuele Tamburini (italy) Flap reconstructed Mandible With dental implants Objectives: The objectives of the “ridge build-up technique” are to simplify the Sermet Sahin (Turkey), Metin Sencimen, Hasan Ayberk Altug, Gurkan Rasit Baykar hard tissue augmentation procedure and to reduce discomfort for the patient. In damaged extraction sockets it is better to wait some weeks until the infected Objectives: This case report describes the surgical and prosthetic rehabilita- site has healed. The biological approach of the post-extraction protocol is to tion process of a case of excessive bone and soft tissue defect secondary to a augment the alveolar bone with biomaterials in the early phase of the healing facial gunshot injury. process. Methods: A 34-year-old male patient who had received a vascularized fibula flap Methods:The surgical protocol provides for the avulsion of irredeemable secondary to a gunshot injury involving the left side of the mandible presented teeth because of abscess. Three to six weeks from extraction, the augmen- to the Gülhane Military Medical Academy, Department of Prosthodontics, com- tation procedure is carried out using current biomaterials only. The volume plaining of difficulty in chewing and distorted physical appearance. According to of biomaterials, membrane included, exceeds the volume of original alveolus the patient’s history, the fibular grafting had been performed two years previous- in order to provide for resorption of bone substitutes. The surgical protocol ly and healing had been uneventful. Dental implants were subsequently inserted. is designed in such a way as to make the exposed surface of the surgical Due to inadequate vestibular sulcus depth, vestibuloplasty combined with split- site resemble a post-extractive alveolus. It is possible to recover and rotate thickness skin grafts harvested from the post auricular area was performed. the abundant repair connective tissue from the alveolar defect on the colla- results: The surgical process produced satisfactory functional and aesthetic gen membrane. Bacterial wound proliferation is controlled with clorexidine outcomes. mouthwashes and application of hyaluronic acid. After 1 year, the implant and Conclusions: The posterior split thickness skin grafts are useful in the treat- fixed crown are inserted into the augmented bone (baseline) and observed for ment of cases with inadequate vestibular sulcus depth. We believe that this is 1–4 years of follow-up. an effective and reliable technique for composing attached gingival. As a result, results: Soft tissue results: the exposed surface of the membrane is covered our patient demonstrated successful prosthetic and functional results. after 1–2 weeks and is sealed by soft tissue after 4–6 weeks. Hard tissue aug- mentation. The greatest linear horizontal and vertical bone gain are detected by cone-beam computed tomography. Clinical evaluations are performed be- 104 i alveolar Bone regeneration using anorganic fore extraction, 3–6 weeks after extraction (“control” wound healing), 1 year af- Bone Matrix and platelet-rich plasma ter the augmentation procedure and 1–4 years after implant of the prosthesis. No implant or prosthesis loss, biological complication or patient discomfort is antonin Fassmann (Czech republic), Peter Augustin, Jan Vokurka, Lydie Iza- observed. kovicova Holla, Jiri Vanek Conclusions: Like the ridge preservation technique, surgical secondary inten- tion wound healing with current biomaterials is also possible without problems Objectives: Tissue engineering is a progressive regeneration procedure and is 3–6 weeks from extraction. Bone volume after 1 year is enough to insert a suc- used in several medical specializations such as periodontology, implantology cessful implant into the augmented site. The limitation of this technique lies and orofacial surgery. in the difficulty of precisely predicting the final coronal shape of bone and soft Methods: Platelet-Rich Plasma (PRP), autologous growth factors concentrate, tissue. In any event, it is possible during implant surgery to correct bone and can significantly enhance the physiological regeneration of tissues. PRP is ac- gingival contour with biomaterials or a connective tissue graft. tivated by adding thrombin and calcium and is applied together with anorganic bone matrix as a composite gel during guided tissue regeneration procedures. results: Alveolar augmentation in a patient with severe periodontitis is pre- 102 i aesthetic and Functional reconstruction Of Severe sented. After multiple extractions, only a narrow alveolar ridge remained, with atrophic Maxillary alveolar Crest By autogenous Bone Graft little retention for a partial denture. After alveolar ridge treatment and removal and dental implants of granulomatous tissue, osteoplasty was performed. A composite gel was implanted and covered with resorbable collagen membrane. A temporary re- Sermet Sahin (Turkey), Metin Sencimen, Hasan Ayberk Altug, Aydin Gulses movable denture was given to the patient after the procedure. After 6 months, endosseous implants were placed in the maxilla and a metal ceramic bridge Objectives: Although many osseous augmentation techniques have been de- was cemented on to the osseointegrated implants. veloped, autologous bone grafting remains the gold standard in maxillofacial Conclusions: The procedure leading to the full cosmetic, functional and social reconstruction. Various donor sites for bone grafting have been investigated rehabilitation of the patient using this progressive surgical approach will be and described in the literature, including the tibia, fibula, calvarium, scapula, presented step by step . clavicula and ilium. In addition, local bone grafts from the maxilla and man- dible have also been used. The obvious advantages of local bone graft are con- venient access, low morbidity, short healing periods, minimal graft resorption 105 i immediate implants in The aesthetic zone. and maintenance of high bone density. The aim of this report is to describe a Technique to preserve The Buccal Wall the treatment and rehabilitation of severe bone loss with autogenous graft and dental implants. Celia alves (portugal), André Correia, professor, Manuel Neves Methods: This paper demonstrates the surgical and prosthetic rehabilitation process of a patient with excessive bone loss in the anterior maxilla, secondary Objectives: The aim of this paper is to present a novel technique for preserv- to a gunshot injury. ing the buccal wall dimensions when performing an immediate implant in the results: The use of autologous bone grafts with osseointegrated implants is aesthetic zone. Immediate implants in the aesthetic zone are a challenge to a well-accepted procedure in oral rehabilitation. Bone harvesting can cause the clinician due to the possibility of buccal wall loss with direct consequences postoperative complications such as donor site morbidity and sometimes in the fixed rehabilitation function and aesthetics. Evidence in the literature does not provide a sufficient quantity of bone. Therefore, synthetic biomateri- suggests that immediate placement does not prevent vertical or horizontal re- als have been investigated to be used in conjunction with autogenous bone sorption and that bone regeneration techniques should be applied to ensure grafts. preservation of the shape of the alveolar ridge.28
    • clinical reSearch, caSe rePortSMethods: Methods: After the immediate implant drilling phase, the socket is formed at the same visit and the preparation of the recipient bed and suturingfilled up with Bio-Oss Collagen® (Geistlich Pharma AG® Switzerland) trimmed techniques were similar. Test and control treatments were randomly assignedwith a cone form, in order to closely adapt it to the socket buccal wall. Then, to either recipient sites, and they were sized similarly to cover the wound bedthe implant is placed with a low rotation speed (15rpm) into the drilled socket, and stabilized with sutures. Patients were seen in follow-up at 2, 4, 6, 8 and 13pushing the Bio-Oss Collagen® buccally and making it more condensed. weeks and then recalled for long-term examination at 12 months. A soft tissueresults: Results: The technique presented uses a material that is mouldable biopsy was obtained from both test and control sites at 13 weeks from fourand easy to place into the extraction socket just before implant. As Bio-Oss® patients for histological examination.(Geistlich Pharma AG® Switzerland) particles are linked by the porcine col- results: All patients healed uneventfully without any graft-related adverselagen, the material condenses better during the implant insertion. At the 6 events. The test and control sites exhibited normal healing, with excellent co-months follow-up visit, the Cone-beam CT scan (I-CAT® Imaging Sciences) lour and texture at the test sites equalling tissue maturation at the control sites.showed both vertical and horizontal stability of the buccal bone. No clinical The 12-month examination revealed that the increase zone of attached gingivachanges were observed in the facial soft tissues of the immediate implants remained stable for both groups. Unlike the control sites, the tissue contour,and peri-implant soft tissues showed normal values for pocket depth and at- colour and texture of the test sites blended nicely with the native adjacent softtachment loss. tissues. The Wilcoxon signed rank test for pre and postoperative measurementsConclusions: Conclusion: In immediate implant cases in the aesthetic zone, revealed a statistically significant increase in the amount of keratinized gingivathis technique may be very helpful in order to reduce resorption of the buccal for the test (P = 0.041) and the control group (p = 0.042). No statistically sig-wall, since it promotes excellent biomaterial compaction between the implant nificant differences were found on all other measured parameters. The Mann-and the alveolar wall. Whitney U Test did not find statistically significant differences between the test and control groups on any examined variable, including changes in keratinized gingiva and epithelial thickness. The histological findings between test and con-106 i deproteinized Bovine Bone Matrix in periodontal trol sites were remarkably similar for each patient. Mature connective tissueregeneration in Organ Transplant patients was covered by well-formed keratinized epithelium, over which a small band of dense orthokeratin was consistently found. The rete peg morphology of test andpeter augustin (Czech republic), Augustin Fassmann, Jan Vokurka, Lydie Iza- control specimens appeared similar for each patient. In all instances inflamma-kovicova Holla, Hana Poskerova, Jarmila Celerova tory cells were notably absent. Small fibrous remnants of collagen matrix were the only evidence that a graft material had previously been placed.Objectives: Organ transplant patients are successfully treated with complex Conclusions: The results of this study comparing Mucograft to autogenousimmunosuppressive therapy. gingival graft identified the likelihood of the Mucograft being a viable alterna-Methods: Drug-induced gingival overgrowth (DIGO) is an unwanted side effect tive when the goal of therapy is to increase the zone of keratinized tissue andof the therapy. Drugs inducing DIGO are Cyclosporine A, Azathioprin, Myco- obviate the need for palatal harvest. This is especially true in areas of reason-phenolate, Verapamil and Nifedipine. Many other etiological factors contribute able vestibular depth and minimum musculature.to the condition and are further aggravated by oral biofilm accumulation. Fi-brosis, inflammation and cell accumulation depend on doses, time and type ofdrug administrative, oral hygiene and individual reaction of organism. 108 i platelet-rich Fibrin in The Treatmentresults: We are using our treatment protocol: After patient hygiene instruc- Of Bilateral Gingival recessionstions, scaling and root planing (SRP), the surgical treatment (gingivectomy) isperformed. After six months, regenerative periodontal therapy using tissue en- Gulnihal Eren (Turkey), Gul Atillagineering with deproteinized bovine bone matrix (DBBM) and platelet rich plas-ma (PRP) is started. After activation with thrombin and calcium, a composite Objectives: Coronally advanced flap (CAF) + connective tissue graft (CTG) hasgel is prepared for implantation into periodontal defects. The gel is covered with been suggested as the most predictable technique for correction of recessionresorbable collagen membrane. Degranulation of thrombocytes and release of defects. However, CTG technique necessitates a second surgical site and in-growth factors significantly improve the quality of periodontal regeneration. creases the risk of morbidity linked with harvesting the autogenous palatal do-Conclusions: The poster demonstrates the use of this method in patients with nor mucosa. Platelet-rich fibrin (PRF), containing autologous growth factors,drug-induced periodontitis following transplantation of heart and kidney. This has been thought to accelerate soft tissue healing. The use of PRF in treatmenttherapeutic practice is performed successfully. of gingival recessions eliminates the requirement for a donor site. The aim of this case report is to evaluate the clinical effectiveness of coronally advanced flap CAF+PRF combined technique and also to compare its results with CAF+107 i The use Of Mucograft® Collagen Matrix To augment CTG in the treatment of bilateral gingival recessions.The zone Of keratinized Tissue around Teeth Methods: This case report concerns the surgical treatment of a 22 year old pa- tient with bilateral gingival recessions in maxillary canine incisors. Sites wereSoo-Woo kim (uSa), David Kim, Peter Schupbach, Marc Nevins randomly assigned into CAF+PRF (test) or CAF+CTG (control) groups. Clinical periodontal parameters were recorded at baseline and at 1, 3 and 6 months.Objectives: The importance of a functional and healthy mucogingival complex Clinical photographs were taken at baseline and at 1, 3 and 6 months and theto underlying osseous stability around teeth is evident by the increasing atten- recession area analyzed by digital image analysis (ImageJ Windows, Nationaltion given to soft tissue augmentation procedures in clinical practice. An intact Institutes of Health, Bethesda, MD). Soft tissue thickness was also evaluatedattached band of keratinized gingiva is seen as a critical component to the pro- at baseline and at 6 months.tective function of the mucogingival complex, although minimum width require- results: Root coverage amount, soft tissue thickness levels, increase in kera-ments of this tissue type remain controversial. The exact quantity of attached tinized tissue depth, clinical attachment level and probing depth were improvedgingiva necessary for maintaining periodontal health has not been defined, but a for both study groups. The test group showed better wound healing than thenumber of studies suggest that it necessary to have a minimum of 2 mm of ke- control group at the 10th day. Fewer complications were also recorded in theratinized gingiva for sustainable periodontal health. The purpose of our prospec- test group, due in particular to the fact of not having a donor site.tive split-mouth case series was to evaluate the safety and efficacy of Mucograft® Conclusions: Based on the results, CAF+PRF technique is a predictable treat-(Xenogenic porcine bilayer collagen matrix) as an alternative to the autogenous ment for gingival recessions. PRF may accelerate wound healing and causegingival graft in procedures designed to increase the zone of attached gingiva. less patient discomfort in the treatment of gingival recessions.Methods: Five healthy patients presenting with 2 mm or less bilaterally of at-tached keratinized gingiva on the buccal aspect of mandibular posterior teethwere recruited. Plaque and Gingival Indices as well as probing pocket depth, 109 i use Of Nanocrystalline Hydroxypatite in Blocks For Bone Graftgingival recession, and the amount of attached gingiva were determined at the in atrophic areas. Clinical, Tomographic and Histological analysisbuccal aspect of each test (Mucograft) and control (autogenous gingival graft)tooth and again at 12 months. Both the test and control procedures were per- Sergio Gehrke (Brazil) 29
    • Objectives: The objective of this study was to evaluate the performance of the Guilherme piragine, Marco Pontual, Hedilberto Sousa, Danielle Lima, Marco nanocrystalline hydroxyapatite in blocks NanoBone® (Artoss GmbH, Germany) for Bianchini the recovery of atrophic areas to allow subsequent placement of dental implants. Methods: Performance was assessed through clinical and tomographic follow- Objectives: To demonstrate through Cone Beam CT image the horizontal and up as well as histological examination to evaluate the osteogenic potential of vertical gain in bone volume 6 months after grafting surgery with functional the material in six patients. prosthetic rehabilitation on implants of different diameters in the posterior results: The samples showed a large bone formation inside the blocks. Clini- mandible. cally we observe a proper consistency of newly formed tissue, allowing stabi- Methods: Patient MR, 53, female, leukoderma, came complaining of difficulty lization of the implants. Tomographically, the grafted blocks showed adequate in chewing due to lack of teeth in the posterior region of mandible, failing to radiopacity, enabling control and evaluation to be carried out. make use of removable partial denture. Cone beam tomography of the man- Conclusions: The results show that nanocrystalline hydroxyapatite in blocks dible showed initial marked loss of bone volume to be deployed in the regions NanoBone® is very promising for use as a graft material to obtain volume, be- (34-36, 44-46). Due to the length and proximity of donor and recipient sites, the cause it promotes higher cellular activity and bone substitution. surgery, which involved reconstruction of bilateral mandibular bone height and thickness with autograft taken from the symphysis mandibular and left ramus mandibular, was performed in a hospital environment. During the reconstruc- 110 i Bone regeneration in Maxillary anterior region tive surgery, the bone blocks were stabilized to the recipient site and fixed 1 By Microplate and Non-resorbable Membrane mm above the crest to induce bone height gain. After six months of the new cone beam tomography grafted region was ordered after surgery to install 05 Jung-Bae dan implants (Straumann SLA-active). After 4 months the patient was rehabilitated with fixed prostheses screwed. Objectives: Block bone grafts have been widely used in the reconstruction of results: Flap debridement exposing all the donor and recipient sites allowed the maxillary anterior region. Recent advances have enabled clinicians to deal repositioning of normal tissues, so the volume of the bone blocks was pre- with various situations. The author attempted to regenerate the bone in the served by the absence of tension, and since the patient did not use the prosthe- maxillary anterior region using a microplate and non-resorbable membrane. sis during the healing period there was also no pressure on them. The grafted Methods: The 45 year old female came to WooJung Dental clinic in Seoul, Ko- area showed a gain in height (H) and thickness (T) after 6 months, region 34 rea with a left central incisor displaying severe mobility. (H-0.1mm / T-2.6mm), region 35 (H-3.3mm/T-3.5mm), region 36 ( H-4.7mm/T- After extraction of the left central incisor, the bone graft was delayed for 2 3.9mm), region 45 (H-6.8mm/T-3.6mm) and region 46 (H-7.4mm/T-5.2mm). months until the soft tissue had matured. After soft tissue maturation, the The volume obtained permission to install the parallel implants, and centered bone graft procedure was performed. There was severe bone destruction in on the rim and without any complications such as detachment of the block the buccal plate. graft, or trepanning exhibition breathes. The bone blocks were well adapted About 5 mm vertical loss was observed in the buccal plate. A 5-hole-length to the original bone with good vascularization and density. In the region of el- microplate (Jeil Medical Corporation,Korea)was bent to fit the contour of the ement 44 it was decided not to install the implant, since a bone defect was facial bone and fixed with bone tack (Frios®,Germany). BioBarrier (Imtec®,USA: found that could have jeopardized a successful outcome. Screw-retained metal non-resorbable, non-porous type) was fixed from the lingual side with bone tack. ceramic fixed prostheses were fabricated. The right side of the prosthesis re- Irradiated cancellous bone and marrow (Rocky Mountain Tissue Bank, USA) ceived the cantilever element 44. 0.25g and Cerasorb (Curasan,Germany) 0.5cc mixed with PRGF (Platelet Rich Conclusions: The surgical technique has enabled the volume of the bone in Growth Factor) were placed under the membrane. Finally, bone tack was blocks to be maintained due to modification of the incision providing free ac- fixed to the covering membrane to stabilize the bone graft. cess to donor and recipient sites and the repositioning of the flap free from results: After 8 months, re-entry was performed and the implant installation tension. Rehabilitation with implants in grafted area is a treatment used in carried out. At this time, the core of the graft site was taken out by trephine clinical practice, but still more studies are needed in order to assess the sur- burr. Though some Cerasorb particles maintained their integrity in macroscop- vival rate of these implants, as well as the stability of the bone volume around ic appearance, primary stability of the implant was good. The microscopic ap- prosthetic implants. pearance of the graft core showed some degree of bone formation. The second operation was performed 3 months later. A papilla-saving incision helped to conserve papillae. Though some degree of bone resorption was observed in the 112 i Two year Follow-up Of an autogenous crestal region, the replacement of Cerasorb by bone had progressed relative to Transplantation Of Maxillary Molar the previous state (i.e. at installation). Final restoration shows good harmonious appearance with adjacent tooth and Ozgun Ozcaka, Kanik Ozgur, Bicakci Tolga, Arikan Fatih soft tissue. The soft tissue has a firm and healthy appearance. The author experienced the benefit of soft tissue maturation. Thick, firm and Objectives: Autogenous tooth transplantation has been used as a predictable healthy soft tissue is important in order to avoid membrane exposure and for surgical approach to correct malocclusion and replace edentulous areas. The the success of the bone graft and long-term maintenance in the anterior re- purpose of this case report is to describe a patient undergoing autotransplan- gion, where aesthetics are a major concern. The author recommends a staging tation of an impacted maxillary third molar into the socket of the extracted approach for graft sites with weak soft tissue. Furthermore, even soft tissue second maxillary molar. enhancement is needed for successful implant. Most clinicians have major Methods: A 54 year old systemically healthy male subject was referred concerns for bone in GBR and for the coupling action of osteoblast and os- for dental treatment on his right maxillary second molar. Panoramic and teoclast: the author likes to use the term “coupling action of bone and soft periapical radiographs revealed the existence of a periapical lesion and tissue”. The microplate technique is a non-invasive, time-saving procedure periodontal bone loss. Tooth extraction was therefore indicated. The same without bone harvesting. clinical and radiographical examinations showed that the unerupted right Conclusions: 1. The staging approach to soft tissue maturation was beneficial maxillary third molar was healthy and suitable for tooth autotransplanta- and contributed to the success of the GBR and to the aesthetic aspect. tion. The procedure involved transplantation of the third molar into the ex- 2. GBR through microplate was a non-invasive and time-saving procedure traction socket of the non-restorable second molar. Five basic procedural compared with block bone graft. steps were taken: 1) atraumatic extraction, 2) apical contouring of bone at 3. Sufficient bucco-lingual bone dimension was secured through use of the the transplantation site, 3) preparation of a 4-wall bony socket, 4) avoidance microplate. of premature occlusal interferences and 5) stabilization of the tooth with placement of a cross suture. The patient was recalled at 1, 3, 6, 12, and 24 months. 111 i Gain Of Bone Height and Thickness in The posterior results: No differences were found in clinical periodontal parameters at 1, Mandible using Bilateral reconstruction With autogenous Graft 3, 6, 12 and 24 months. At the two year follow-up, no pathological signs were Of ramus Mandibular and Mentum detected clinically or radiographically.30
    • clinical reSearch, caSe rePortSConclusions: Autogenous transplantation of the third molar may be consid- bances due to mental nerve compression. Pre-operative CT Scan measurementsered as an alternative to prosthetic and implant rehabilitation treatment in loss at the symphysis revealed 4 mm. of residual ridge height and 6 mm. of width. Theof first and second molars. procedure was performed under conscious sedation and local anaesthesia. A full thickness flap in the anterior area and a partial thickness flap in the posterior area were performed to avoid nerve damage. GBR was performed using a xeno-113 i The Outcome Of implant rehabilitation graft (Bio-Oss) and a titanium-reinforced e-ptfe membrane (Goretex). Mattressin The anterior Maxilla With a papilla-preserving sutures provided primary closure. After 6 months of healing time the membraneincision Technique and Grafting: a Case report was removed and three implants were placed (Branemark System) in the inter- foraminal area. Resonance Frequency Analysis (RFA) was used to assess pri-aysun kaya, Turker Ornekol mary stability. A core sample was obtained for histological analysis. results: Post-operative CT scans after 6 months of healing revealed 12 andObjectives: To prevent the regression and recession of soft tissue and underly- 6mm of vertical and horizontal bone height gain, respectively. The newly gen-ing hard tissue after the extraction of an infected tooth. erated bone allowed for the placement of three dental implants to support anMethods: Tooth # 21 extracted due to persistent apical infection and extru- implant-assisted overdenture. Primary stability of the implants was achievedsion. Immediately after extraction, socket was augmented with allograft (Bio- and measured by means of RFA. Implant Stability Quotient (ISQ) measure-oss,Geistlich Biomaterials) and opening of the socket was covered with a re- ments taken at the mesial, distal, buccal and lingual aspects of each implantsorbable membrane(Bio-Gide,GB). As a temporary, extracted tooth crown was ranged from 66 to 76. Histological analysis revealed vital and mature bone sur-trimmed and bonded to the adjacent teeth to block the opening by pressing rounding Bio-Oss particles.over the membrane. Two weeks from the extraction, a 5x10 mm tapered Nobel Conclusions: Within the limitations of this case report, we can conclude thatReplace implant (Nobel Branemark) was placed. A papilla-preserving incision GBR is a valid technique for bone reconstruction in cases of severe mandibulartechnique was used to elevate the flap, keeping the papillae intact. Guided bone resorption, avoiding the use of autogenous bone grafts and the consequentregeneration (GBR) technique was used in conjunction with the implant place- donor site morbidityment. A Maryland bridge was cemented in for the healing period immediatelyafter the surgery. Six weeks after the surgery, a screwable temporary crownwas produced to remodel the surrounding soft tissue. Twelve weeks after the 116 i a Combination Of zygomatic Fixtures, autograft, allograftsurgery, a permanent Procera Zirconia ceramic crown (NB) was cemented on and prp (platelet-rich plasma) Or prF (platelet-rich Fibrin)to the procera zirconia abutment (NB). allows a Fixed prosthesis rehabilitation Of Extremely resorbedresults: On post-operative examinations, a stable state both in the alveolar bone Or accidental Bone loss in Edentulous Maxillacontour and on soft tissue topography was observed. 1 year and 2 year follow-up sessions showed minimal (negligible) tissue loss distobucccal to the crown. laurence Evrard, Yassin Bouzelmat, Ramin Atash, Régine GlineurConclusions: GBR is essential to prevent the collapse of surrounding tissuesafter the extraction. The papilla-preserving incision technique and placement Objectives: For the maxilla, in the case of post-traumatic loss or of majorof a provisional prosthesis are also important requirements for achieving suc- post-edentation resorption, functional and aesthetic rehabilitation with a fixedcessful functional and aesthetic outcomes in the maxillary anterior region. prosthesis can be achieved by means of two or four zygomatic fixtures plus two to four conventional implants in the anterior region. In these cases, a reconstruction of the anterior part of the maxilla can be performed, using a114 i Horizontal reconstruction of alveolar ridge bone autograft supplemented by an allograft and platelet concentrates (PRP orusing autogenous block bone graft PRF), which have been shown to enhance the maturation rate of bone and bone density and to accelerate resorption of some biomaterial particles.albert Barroso panella (Spain), Pablo Altuna Fistolera, Albert Calaf Cot Methods: Clinical cases are presented, involving placement of two to four zygomatic fixtures, in conjunction with a cranial or mandibular symphysisObjectives: The aim of our communication is to expose a case series in which autograft, supplemented by use of Freeze Dried Bone Allograft (FDBA) andwe have used the autogenous block bone graft for the management of the hori- Platelet-Rich Plasma (PRP) in the form of gel and membranes. Biopsies werezontal alveolar defect and to evaluate the results and the complications. taken 4 to 6 months after bone grafting, at the time of implant placement in theMethods: A case series are presented and the results are compared to late region of the anterior maxilla. Histological analysis was performed, in order topublications. All of the cases presented moderate-severe horizontal alveolar evaluate the effects of PRP on bone maturation and bone density, in the caseridge defects. All of them have been reconstructed with intraoral autogenous of a bone autograft used in conjunction with an allograft. The four year clinicalblock bone graft. A follow up of 6 to 36 months has been done. The results are results are presented.analyzed depending on: kind of device used for the osteotomy, location of donor results: Histological sections show the very good degree of maturation of thesite, morbidity of the donor site and possible complications. reconstructed bone (lamellar bone, poor cellularity, absence of inflammatoryresults: The results have become to be favourable by using these techniques after infiltrate). X-rays show the level of bone around implants.an average follow up of 16 months. These results are in accordance to actual lit- Conclusions: The results presented here show that PRP used in conjunctionerature, in which the survival rates and the aesthetic results are very satisfactory. with allografts and autografts produces very good bone quality and density,Conclusions: The use of the intraoral autogenous block bone graft for the re- allowing implants to be placed. After four years of functional load, all implantsconstruction of the alveolar ridge seems to be predictable for the rehabilitation are successful.with fixed prosthesis of our patients. 117 i Minimally invasive removal Of a115 i Bone regeneration in Extremely dental implant displaced into The MaxillarySevere atrophic Mandible. a Case report. Sinus using dental Mini-C-arm Fluoroscoperadia Hrichi, Joan Pi Anfruns, Joan Pi Urgell uilyong lee, Pillhoon Choung, Jongho Lee, Juhyung Yi, Mihyung KimObjectives: The objective of this case report is to present a non-invasive tech- Objectives: A dental implant displaced into the maxillary sinus must be re-nique for bone regeneration in an extremely atrophic mandible with GBR utiliz- moved because the implant can cause sinusitis by disturbing mucociliarying a xenograft in combination with a synthetic barrier to allow the placement clearance or causing tissue rejection. Implant migration into the maxillary si-of dental implants. nus has been reported several times. To remove foreign bodies dislodged intoMethods: A 75 year-old female, edentulous in both maxilla and mandible with the maxillary sinus, three treatment options have hitherto been proposed inextremely severe bone atrophy (type E). The patient’s chief complaint was in- the literature: suction from the socket, classical open surgery via the caninestability of the lower denture with severe functional problems and nerve distur- fossa and the endoscopic approach. 31
    • We describe a method to retrieve a displaced dental implant from the maxillary hydroxyapatite and 40% beta-tricalcium phosphate, while inorganic bovine bone sinus using a dental mini-C-arm fluoroscope. The unit used in this study was a matrix (ABBM) is manufactured from bovine bone mineral. This study evaluated DreamRay®. The DreamRay® fluoroscope was specifically developed for dental the efficacy of MBCP (MBCP) to ABBM (Bio-Oss®) in the histomorphometrical implant surgery, endodontic treatments, tooth extractions and preparations aspects of new bone formation in maxillary sinus augmentation. for fillings. The light weight and compact design of the DreamRay® enables Methods: Eight patients were selected after a medical and dental examination. it to be moved easily and used in any location and orientation during dental Patients had insufficient residual bone height (less than 5 mm) for simulta- procedures. neous installation of implant fixtures on maxillary posterior regions. Residual Methods: We retrieved the dislodged dental implants from the maxillary sinus bone height was measured by a CT scan. in two patients through the socket using a mini-C-arm fluoroscope. The socket They were divided into two groups as determined by randomization and un- was expanded to 6 mm for further instrumentation. In the beginning, we tried derwent maxillary sinus floor elevation and bone grafting using MBCP (n=4) to remove the implant using a mosquito by viewing fluoroscopic images. Real- or Bio-Oss (n=4). After a healing period (average 6.5 months after surgery), time fluoroscopic imaging facilitated delicate control of the mosquito in order bone cores were harvested for a histomorphometric evaluation and the implant to grab the implant. However, controlling the mosquito through the socket fixtures were installed. These bone cores were decalcified and 5 um thick sec- proved to be difficult. Thus various surgical curettes were used to drag the im- tions were cut along the longitudinal plane using a microtome. All sections are plant toward the socket. Finally, the implant was positioned close to the socket stained with Hematoxyline-eosin and evaluated via light microscope coupled to and retrieved using suction. a video camera. The percentage of the different components of the harvested results: The dislodged dental implants were removed successfully. It took only tissue (i.e., new bone, residual bone particles, and soft/marrow tissue) were 5 minutes to remove the slipped implant, which had been dislodged into the calculated and recorded. maxillary sinus. The enlarged socket was then covered with a collagen mem- results: Healing process after sinus graft procedure was uneventful, even though brane and primary watertight closure was done with 4-0 black silk. The pa- small tears (‹ 5 mm) occurred in two sinuses. Bone cores were obtained 22 to 36 tients returned for follow-up appointments and the wounds healed well. weeks post surgery. Histomorphometric analysis of 4 MBCP cores and 4 ABBM Conclusions: By using a mini-C-arm fluoroscope to remove the dislodged den- cores revealed an average of new bone of 26.94% and 28.94%, respectively. The tal implants from the maxillary sinus through the socket in two patients, we percentage of residual graft particles was much less in MBCP (11.59% vs. 31.10% confirmed that the mini-C-arm is an effective and minimally invasive method for ABBM) with more soft and marrow component (61.47% vs. 39.96% for ABBM). for retrieving displaced dental implants. The amount of new bone formed in the sinus does not seem to be related to the length of healing time. The gross histology of the retrieved tissues was similar for the both types of graft material. Histological evaluation revealed that most of 118 i Bone quality Enhancement By platelet Concentration Method the graft particles, both MBCP and ABBM, were surrounded by or embedded in new bone, and in close contact to surrounding new bone. The boundary between Jung-Bae dan (korea) particles and new bone was irregular and the contact was close, implying the resorption of particles with the simultaneous apposition of new bone. Objectives: Weak bone quality is a challenge for successful implantation. Conclusions: Since the number of patients and sinuses was limited, the Especially in an extraction site in a severely inflamed condition, bone heal- data obtained in this pilot study should not be considered conclusive. How- ing is not good. Even after a long period of healing time, bone quality is very ever, histological appearance showed that both materials have osteoconduc- poor on that site. The author experienced implant failure after loading . The tive properties. Both materials are, therefore, appropriate for maxillary sinus author concluded the reason for failure was poor bone quality because the augmentation followed by dental implant placement. It is not known whether ISQ value during healing was so low and didn’t go up well. There have been differences of percentage obtained in histomorphometric analysis have any many implant surfaces to enhance osseointegration. But there are so few clinical relevance. bone quality enhancing methods for a osteotomy site with poor bone quality. So the author tried to enhance the bone quality at the osteotomy site with poor bone quality. 120 i different Technique Of ridge Splitting according Methods: The author installed 2 Straumann implants in the maxillary posterior To The Thickness Of The Buccal plate: Clinical Cases report region. One of the implants shows some peri-implant radiolucency and mobil- ity. That implant was removed after some loading period. After removal of the dong Wook Chang (korea) implant, synthetic bone material(Cerasorb) was filled. After the healing period, reimplantation was practiced. At installation, the ISQ Objectives: Narrow alveolar ridges are a serious challenge for successful im- value was not estimated for very low stability. PRGF (Platelet-Rich-in-Growth plant placement. The ridge split technique seems to be a predictable technique Factor) was prepared from venous blood. And the Straumann implant was to correct narrow alveolar ridges as compared to onlay bone graft and GBR. soaked with PRGF. Excess PRGF filled the osteotomy site. Ridge splitting can be applied in both maxilla and mandible. But generally, results: 3 weeks later, the ISQ was estimated. The ISQ value was 44. 6 weeks bone splitting in the maxillary ridges with mostly lower bone density and thin- later ISQ went up into the seventies. ner cortical bone plate can more easily be performed than in the mandibular Conclusions: Implant surface and poor bone quality osteotomy site was en- ridges with the denser bone of buccal plate. Occasionally, maxillary ridges hanced by PRGF. PRGF assisted implant installation was strong for poor bone with thick buccal plate are present. Therefore, a different method must be ap- quality osteotomy site. plied in the thick and thin buccal plate respectively. In the thin buccal ridges, mostly maxillary ridges, ridge splitting requires crestal and vertical osteotomy. In thick buccal ridges, ridge splitting needs long vertical osteotomies and/or 119 i Histomorphometric Comparison Of a Macroporous Biphasic basal horizontal osteotomy to prevent buccal plate fracture additionally. Calcium phosphate and inorganic Bovine Bone For Maxillary Sinus Methods: Case I is ridge splitting with simultaneous implant placement in the augmentation in Human: a pilot Study maxillary ridge with thick buccal plate. Full thickness flap was elevated and mid-crestal osteotomy with a piezoelectric device was performed in the alveolar Ji-Hyun lee (korea), Ik-Sang Moon ridge. Then long vertical osteotomies on the mesial, distal side were performed apically. Ridge expansion was performed with a chisel osteotome. Then the im- Objectives: The maxillary sinus augmentation technique has been considered plant was inserted into the widened alveolar crest. And then the defect was cov- as a routine procedure to achieve sufficient vertical bone height on the maxillary ered with bone graft material and bioresorbable membrane. The primary closure posterior region with severe alveolar bone resorption. As far as bone grafting was achieved. Case II is ridge splitting in the mandibular ridge with thick buccal material for sinus augmentation is concerned, it is still accepted that autog- plate. After flap elevation, mid-crestal osteotomy with piezoelectric device was enous bone graft is the gold standard. However, many researchers have studied performed in the alveolar ridge. Then the vertical osteotomies on the mesial and other bone substitutes, due to limitations affecting the harvesting of a sufficient distal side and additionally basal horizontal osteotomy was performed. After the amount of bone and the need for a second surgical site. In particular, macropo- expansion, the widened alveolar crest was filled with bone graft material and rous biphasic calcium phosphate (MBCP) belongs to alloplast, consisting of 60% covered with bioresorbable membrane. The primary closure was achieved.32
    • clinical reSearch, caSe rePortSresults: Case I. 4 months after ridge splitting with simultaneous implant compromised the restorative-driven approach to implantation. Vertical boneplacement, 2nd surgery was performed and the implant was surrounded in augmentation where horizontal bone loss has occurred is still regarded as aregenerated bone at the ridge split site without thread exposure. And then 1 challenging topic.month later, implant prosthesis was completed. Methods: A fourty-five year old female with a severely deteriorated maxillaryCase II. 5 months later after ridge splitting, 2nd surgery was performed and the lateral incisor requested an implant in order to make a fixed restoration. Se-regenerated bone in the ridge split site was sufficient to implant the placement. vere bone resorption circumferentially around the root had lost the neighbour-Conclusions: As regards the thin buccal plate, ridge splitting requires only ing proximal septum and jeopardized the standard procedure. We used guidedcrestal and vertical osteotomies. On the other hand, as regards thick buccal bone regeneration using a xenograft and barrier membrane for bone replace-plate, ridge splitting needs additional osteotomies such as long vertical oste- ment after tooth extraction. Late implantation was performed and final crownotomies, basal horizontal osteotomy. delivered after healing period.This ridge splitting technique according to the thickness of buccal plate is reli- results: Uneven healing after bone regeneration, implant placement, andable and enables the buccal plate not to be fractured. loading occurred. Significant amount of new bone gained in radiographic and clinical findings. Primary stability of implant placed in regenerated bone was demonstrated via high insertion torque. Appropriate bone remodelling and os-121 i Clinical Evaluation Of Coronally advanced Flap (CaF) + seointegration was demonstrated by the high score of implant stability (ISQ).Mucograft® in isolated recession Type defects. Case reports Follow up radiographs taken 8 months after loading showed stable bone level around the fixture neck. Clinically, we could deliver an aesthetic crown withoutMarco Clementini (italy), Gianluca Vittorini, Nicola Baldini any significant mismatch with neighbouring teeth. Conclusions: Optimal results in single implantation would be a predictableObjectives: The primary goals of mucogingival surgery have changed over approach even in a compromised situation. Appropriate case selection, flaptime from increasing the band of keratinized gingiva to providing predictable design, and proper materials are necessary for replacing a tooth with reducedroot coverage to satisfy patients’ aesthetic demands. Various different surgi- periodontium.cal techniques have been utilized to augment gingival tissue dimensions. Areview comparing the free gingival graft (FGG), the connective tissue graft(CTG) or the coronally advanced flap (CAF) in recession coverage revealed 123 i reconstruction Of The Critical Size peri-implantnon considerable difference between the individual treatments. In order to Osseous defects With porous Titanium Granulesimprove the predictability of complete root coverage, a new technique hasbeen developed using the CAF in conjunction with CTG. Even if this approach Sermet Sahin (Turkey), Metin Sencimen, Hasan Ayberk Altug, Yesim Erkan,showed improved clinical outcomes, it may be associated with significant pa- Aydin Gulsestient morbidity due to the wound at the palatal donor site. Instead of usingallograft material or autologous transplants, a promising option of avoiding Objectives: Pure titanium and titanium alloys (Ti6Al4V) have been used in thepatient morbidity is the use of collagen matrices from animal origin, such as manufacture of dental and orthopaedic implants because of their superior me-Mucograft® (MG). chanical properties and high corrosion resistance. Porous titanium granulesMethods: The surgical technique utilized to achieve soft tissue coverage is the (PTG) have used in many treatments for dental bone regeneration. The mostCAF for single recession. Following administration of local anesthesia, the flap common are sinus lift, regeneration of bone in peri-implantitis defects andis designed with two vertical releasing incisions and then elevated in a split- post-extraction socket fillings. The aim of this study was to explore the osteo-full-split fashion, the exposed portion of the root is scaled and then conditioned conductive properties and biological performance of porous titanium granuleswith EDTA to remove the smear layer, finally thoroughly rinsed with sterile sa- used in the critical size osseous defects adjacent to titanium implants.line. The MG is cut to size and placed over the dehiscence defect. The matrix is Methods: A 27 year old male patient with multiple implants was referred to ourplaced 3 mm apically to the bone dehiscence and 1 mm from the lateral inci- clinic for treatment. Three months after dental implant insertion, peri-implan-sions (avoid placing MG beneath the sutures) on the prepared mucosal bed and titis occurred with bone resorption in region around the implants. The followingthen sutured in place. Subsequently, the root surface and MG will be covered treatment steps involved debridement; full mouth disinfection and accompany-with the CAF: the tissue flap is secured slightly coronally of the CEJ by the use ing antibiotic treatment aiming to reduce any active inflammation. The muco-of a sling suture placed at the papilla, using non-irritating sutures. The verti- periosteal flap was removed up to the edge of the infected bone. Removal of allcal incisions are closed by at least 2–3 sutures. Light pressure will be applied granulation tissue and cleaning of the titanium surface with curette. The decon-after suturing. tamination of implant and bone was carried out with the tetracycline capsule. Atresults: At 6 months CAF+MG showed very positive outcome measurements in the end of the treatment for regeneration and augmentation, PTG were appliedterms of root coverage and KT width in 4 out of 5 patients, according to the sys- with soft tissue stabilization and renewed pocket formation was prevented.tematic review data available in literature about CAF+CTG; these results seem results: The results of the case show that bone can be regenerated using PTGto be stable and associated with a good aesthetic integration and with healthy (Porous Titanium Granules), and tissue samples show that new bone growsperiodontal conditions; furthermore no signs of inflammation or infection were in and around titanium granules and regenerates the bone tissue around thedetected in the period of observation, all the patients reported only a transient, implant. For the patient and dentist, this means that much time can be saved,slight pain with a very short FANS medication intake. unpleasantness can be avoided and costs can be reduced.Conclusions: These preliminary results suggest this new surgical technique Conclusions: In the literature, PTG have previously shown that titanium is(CAF+MG) could be a reliable alternative to the traditional bilaminar technique much more thrombogenic than the other two. Biomaterials are often used in(CAF+CTG) because of its predictable outcomes in terms of root coverage % implants, i.e. PVC and steel. Apart from their physical properties, the granulesin association with a significantly lower patient morbidity avoiding a palatal have also shown indications of having good biological properties, such as re-donor site duced inflammation and faster coagulation of the blood.122 i Socket augmentation as a useful procedure For replacing 124 i delayed implant placed into Grafted Extraction Socketa Severely involved anterior Tooth By dental implant Of Molar affected By Chronic periapical lesion in MandibleGolamali Golami (iran), Reza Amid Sermet Sahin (Turkey), Hasan Ayberk Altug, Metin Sencimen, Hanand AltugObjectives: Hard tissue deformities are considered to be among the most seri- Objectives: The aim of this case report was to show the clinical outcome ofous limitations on implant placement in a proper position. Different kinds of an implant placed into a grafted extraction socket of molar tooth affected bymaterials and methods are available. Despite the success of bone regenerative chronic periapical lesion.procedures documented in so many publications, bone regeneration has been Methods: A 66-year old partially edentulous male patient with a tooth requir-a controversial issue. Periodontally involved teeth with severe bone loss have ing extraction and chronic periapical lesion was referred to our clinic. Tooth 33
    • was extracted, chronic periapical lesion was curetted and that side was treated the complexity of peri-implant guided bone regeneration of bone loss owing to according to the principles of guided bone regeneration (GBR) by means of spontaneous implant exposure. During the uncovered phase, a subepithelial deproteinized bovine bone mineral particles in conjunction with a bioresorb- connective tissue graft was applied as a biological barrier and for soft tissue able collagen membrane. Survival and radiographic bone loss of implant were closure. evaluated after two years of function. Methods: At 4 months post implant placement using the traditional 2-stage results: Extraction site displayed sufficient new bone volume to allow inser- approach, a spontaneous exposure of the implant cover screw was observed. tion of a dental implant. No complication was recorded with implant and pros- Surgery included a mid crestal incision and full thickness flap elevation and thesis was successful. debridement. Crestal bone resorption exposing 3 mm of 2 implants in the cer- Conclusions: Implant placement into such sites can, therefore, be successfully vical surface was detected. The exposed implant surfaces were cleaned and performed. This procedure can be considered a safe and effective treatment irrigated. Free subepithelial connective tissue graft (SCTG) was harvested option. from the inner side of the palatal flap. The SCTG was perforated in 2 locations and threaded through the neck of the implants with the periosteal side of the connective tissue facing the bone/implants. Healing abutments were placed 125 i Mandibular reconstruction With securing the SCTG in place. Bovine bone mineral, as the filler material, was Tissue Engineering, a Case report. applied beneath the membrane on the exposed implant surface. The SCTG was inserted under the palatal and the perforated vestibular mucosa. Flaps were Vanessa ruiz Magaz (Spain), Federico Hernández-Alfaro, Manuel Ribera, Pablo sutured close to the healing abutments leaving the SCTG exposed in the area Altuna, Eduard Ferrés, Lluís Giner Tarrida between the abutments. results: The healing period was uneventful. Gradual epithelisation of the ex- Objectives: Show a new approach to bone regeneration instead of bone trans- posed graft surface from the surrounding tissue was achieved and at 2 weeks plantation in a 32-year old patient who presented an ameloblastoma in her left nearly all exposed portions of the SCTG were re-epithelialised. At 4 weeks mandibular angle. post operation, a normal appearance was restored without evidence of in- Methods: The area affected by the ameloblastoma was resected using an ex- flammation. The area of the facial keratinized tissue surrounding the implant traoral access. At the beginning of the surgery a bone marrow aspirate from increased significantly presenting a thick type B masticatory mucosa morpho- the iliac crest was centrifuged in order to concentrate the mesenchymal cell type. The donor site in the area of the palatal flap presented no signs of mor- fraction. Using a stereolithographic model of the mandible a titanium mesh was bidity due to the precise excision of the SCTG, without flap perforation, which moulded to recreate the angle of the mandible. Two xenograft blocks mixed with could result in secondary wound healing. At the end of 3-month follow-up, the recombinant human bone morphogenetic protein-2 and stem cells were used to area was asymptomatic, and the implant sites showed no signs of infection or recreate the resected area on the model. Then the titanium mesh and this com- bleeding when probed. The radiographic examination revealed bone gain in the bination of biomaterials were adapted to the mandible of the patient to recreate area of previously exposed implant threads. The implants were restored with the original anatomy. After 6 months three endosseous dental implants were provisional crowns designed to enhance soft tissue contouring and maturing. placed in the regenerated bone to restore the masticatory function of the pa- Conclusions: Soft and hard tissue management following spontaneous expo- tient. At the time of the implant placement bone samples were collected using a sure of implant cover screws, using SCTG, can lead to satisfactory peri-im- trephine bur and were subjected to histomorphometrical analysis. plant healing and enhancement of peri-implant bone level. The wound closure results: The fundamental of tissue engineering is the regeneration of tissue over partially exposed SCTG prevents the displacement of the mucogingival and restoration of function through implantation of cells/tissue grown outside junction and increases the width and thickness of the peri-implant keratin- the body or stimulating cells to grow into an implanted matrix. It is an alterna- ized mucosa. tive to conventional reconstruction methods. The three main components of tissue engineering are scaffolds, cells and signalling molecules. Bone mor- phogenetic proteins (BMPs) are multifunction proteins with a wide range of 127 i resorbable Collagen Membrane Vs. No Membrane biological activities involving a variety of cell types. BMPs comprise the os- in The Sinus lift procedure. a Split Mouth Case report. teoinductive component of several tissue engineering products. In late-stage development they are used as replacements for autogenous bone graft. Stem Basilio Matamoros (Spain), German Solis, Marc Quevedo, Antoni Castellón, cells are unspecialized cells which are characterized by two properties: their Pablo Altuna high self-renewal activity and their multilineage differentiation potential. The xenograft blocks stabilized by the titanium mesh act as a scaffold for these Objectives: To compare the clinical and radiographic changes in a bilateral si- tissue engineering materials that promotes the integration of the graft and the nus lift procedure using a resorbable membrane on one side and no membrane new bone formation. on the other side. Conclusions: In this case the histomorphometric analysis revealed new bone Methods: A 45-year-old male patient came to our dental school clinic seeking formation around particles of xenograft material. This kind of approach made a fixed rehabilitation in the upper jaw. A fixed implant-supported denture was it possible to restore the aesthetics and the functions for the patient with a planned. Both right and left maxillary sinus were pneumatized and a bilateral limited morbidity and treatment time. sinus lift was needed to place implants in the posterior regions. Right sinus was grafted with a bovine xenograft (Bio-Oss®) and covered with a resorbable collagen membrane (Bio-Gide®). The same graft was used to fill the left si- 126 i Subepithelial Connective Tissue Graft as a Biological Barrier nus but no membrane was used to cover the lateral window due to operating Membrane in The Treatment Of peri-implant Crestal Bone complications. After the healing and graft consolidation, eight conical shaped deficiency resulting From Spontaneous Early implant Exposure internal hex Nanotite® implants were placed in the maxilla. After the osseoin- tegration they were rehabilitated with a metal-ceramic fixed denture. avital kozlovsky (israel), Shimshon Slutzkey, Zvi Artzi results: After 7 months of sinus graft healing, a new CT scan was performed to measure the new height of both posterior maxillary regions. Different bone Objectives: Premature exposure of submerged implants predispose to peri- density was observed between both sinuses. On the right side the radiographic implant bone loss which when encountered has to be approached using inter- aspect of the graft was dense and well delimited. In the left sinus the graft was ceptive treatment aimed to restore the bone. Therefore, therapeutic modality dispersed and invaded by less dense tissue. based on the principle of guided bone regeneration (GBR) should be applied. Conclusions: Using a resorbable collagen membrane in the lateral window af- The use of resorbable or non- resorbable membrane is questionable due to ter the sinus lift improved the graft preservation, isolation and maintenance of the risk of exposure and early resorption of the former and contamination of the dimensions. Combining a particulated xenograft and resorbable collagen the latter resulting in impaired bone regeneration. Reclosing the implants to membrane for the sinus lift with the lateral approach is a predictable and well protect the membrane is complicated due to the presented perforation of the documented technique. Absence of a barrier between the graft and the peri- mucosa covering the implants and is a disadvantage due to the need for a sec- ostium may produce a migration of the graft particles and an invasion of the ond surgical intervention. An innovative technique is suggested to overcome connective tissue infiltrating the graft material.34
    • clinical reSearch, caSe rePortS128 i The use Of a New Collagen Matrix (Mucograft®) for bone augmentation with high morbidity of the donor side. This case reportin Soft Tissue improvement around implants demonstrates the possibility of using cortical lamina in small sized alveolar bone defects.Georg Gassmann (Germany), Adrian Lucaciu, Philip KeeveObjectives: Up to now free gingival (fGTG) or connective tissue grafts (fCTG) 130 i Horizontal and Vertical ridge augmentationhave successfully been used in achieving attached soft tissue around dental in aesthetic zone: a Case reportimplants. Recently a new collagen matrix (Geistlich Mucograft®) has beensuggested as a substitute for the autogenous transplants. It is the aim of this aliye akcali (Turkey), Muhittin Toman, Nejat Nizampresentation to clinically show stages of healing up to twelve months after in-sertion in three cases. Objectives: The loss of vital soft and hard tissues after tooth removal can re-Methods: Materials and Methods: In three female patients (mean age 59.4) the sult in alveolar ridge defects which lead to aesthetic and functional problemscollagen matrix was used to enhance peri-implant attached mucosa around six especially in the anterior maxilla. In such defects, soft and hard tissue graftsimplants (2 in the upper posterior / 4 in the lower posterior jaw). Patients gave are often the treatment of choice. In this case report we aimed to demonstrateinformed consent. The matrix was sutured to the neighbouring soft tissue and horizontal and vertical ridge augmentation using bone graft material, titaniumthe periosteum after peri-implant buccal mucosa split-flap preparation. Heal- membrane, and subepithelial connective tissue graft.ing was documented by taking clinical photographs after one, three, eight and Methods: A 66 year old male patient presenting Seibert class III ridge defect infourteen days and after three, six and up to twelve months. According to the the right maxillary central and lateral incisor area and Seibert class I ridge de-McGuire/Scheyer study (2010) Doxycycline 100, Ibuprofen 600 and CHX mouth- fect in the left lateral incisor area was referred to the clinic. The Seibert classwash 0.12% (Paroex®) were administered postoperatively. III defect was reconstructed using bone graft material and titanium membraneresults: Results: Healing was uneventful in all cases. No pain was reported and the Seibert class I defect was treated only with connective tissue graft inby two of the three patients so that they refused to take the pain control medi- consecutive appointments. At the right site, the papilla preservation flap wascation. One patient needed pain control. After 14 days sutures were removed reflected, the defect was filled with cancellous particulate allograft, coveredand complete matrix integration was seen in all cases. A range of 3-9 mm with titanium membrane and flap was closed primarily. At the left site, a pouchenhanced peri-implant attached mucosa without keratinisation was attained was formed in the vestibular area and filled only with connective tissue graft.in the peri-implant cases within the observation period of up to twelve months. The titanium membrane was removed at 6th month. Before 6 and 12 monthsConclusions: Conclusion: The porcine collagen matrix may be used as an au- after the augmentation procedures, clinical periodontal parameters were re-togenous graft substitute in establishing attached peri-implant mucosa. Ac- corded, the impressions were taken and casts were optically scanned in ordercording to conflicting protocols concerning postoperative medication the need to obtain the digital images and make the soft tissue analyses.for postoperatively administered antibiotics seems questionable. results: During the healing period, neither soft tissue dehiscence nor mem- brane exposure were noted. Healing was uneventful at both augmented sites. No differences were found in clinical periodontal parameters during the follow129 i use Of Cortical lamina For Simultaneous Closure Of up period of the case. The alveolar ridge defect was decreased both in verti-Oronasal Fistula, reconstruction Of alveolar defects. a Case report. cal and horizontal dimensions. Soft tissue width was increased at 1st and 2nd months compared to the baseline.atef ismail (Egypt), Khaled Barakat Conclusions: Soft and hard tissue grafts for ridge augmentation in anterior maxillary area could be effective treatment choices in development of functionObjectives: Oronasal defects represent a challenging problem for reconstruc- and aesthetics.tion as there is a need for cortical cover, good adaptability and an easy fixingtechnique. Although the autogenous bone is the gold standard for augmen-tation, it lacks adaptability and there is donor side morbidity and difficulty of 131 i periodontal Bone regeneration Withfixation and stability. Nd: yaG laser and laNap protocolContouring and reshaping of the ridge with cortical contoured bone is considereda real challenge because of the absence of semi-flexible bone. Use of cortical raymond yukna (uSa)lamina can provide semi-flexible degrees customized to the exact defect shape.Methods: A 35 year old male was suffering from nasal fluid discharge during Objectives: The purpose of this presentation is to illustrate the radiographicdrinking following a history of surgical removal of the upper left central incisor. and histological bone regeneration seen following the Laser-Assisted New At-Clinical examination showed loss of contour of alveolar buccal bone with slight tachment Procedure (LANAP) surgery using the Nd:YAG laser in humans.depression at the vestibular site with slight spearing fistula. CBCT revealed Methods: Pre-treatment and post-treatment dental radiographs of patientsloss of apical bone forming a fistula connected to the nasal cavity. Defect analy- treated for chronic periodontitis or peri-implantitis with the Laser-Assistedsis revealed a fistula measuring 3 mm x 5 mm and buccal bone defect measur- New Attachment Procedure (LANAP) surgery using the Nd:YAG laser will being 7 mm wide x 12 mm long. The flap was totally elevated; granulation tissue presented. Cone beam images of some of the patients will be shown. Humanin the bed was excised. histology sections will also be presented.The fistula was curetted to a healthy bone margin. The nasal floor was elevated results: Consistent increase in bone support for both natural teeth (infrabonyand sutured in place. Lamina was dipped in saline for 7 minutes then a piece defects and furcations) and dental implants has been seen with the LANAPwas cut such as to close the fistula, cortices up towards the nose. The defect surgical protocol. The cases shown will illustrate various examples of peri-was filled with collagenized corticocancellous bone chips. The lamina was fixed odontal and peri-implant bone regeneration. Human histology reinforces thein place using 3.0 vicryl sutures to surround periosteum radiographic findings.results: Lamina was tolerated to a convex shape restoring the contour accord- Conclusions: The Laser-Assisted New Attachment Procedure (LANAP) surgerying to the pre CBTC. The flap was scored on its undersurface to allow stretch protocol using the Nd:YAG laser demonstrates appreciable potential for peri-and complete coverage of lamina. No major complication developed postop- odontal and peri-implant bone regeneration.eratively. Minor complications like oedema and lip swelling developed post-operatively increasing after 72 hours and then regressing totally after 7 days.Slight dehiscence appeared at the crestal palatal interface which was treated 132 i rotated pedicle palatal Connective Tissue Flapwith careful cleaning and irrigation and was completely resorbed after 10 days. For Soft Tissue Management after Electrocautery injuryNo nasal discharge was reported by the patient whereas buccal contour wastotally appreciated by the patient. CBCT after 6 months reveals closure of the ilker keskiner (Turkey), Hanifi Ipekdefect and valuable bone formation.Conclusions: Versatility and adaptability of cortical lamina and an easy fixa- Objectives: The incorrect usage of electrocautery in dentistry may cause in-tion method provide a good solution in such a case without secondary surgery juries in gingiva and bone. A surgical procedure, based on a rotated pedicle 35
    • palatal connective tissue flap containing periosteum to achieve primary soft Objectives: The purpose of this case report is to evaluate the clinical and ra- tissue closure and to preserve the alveolar bone in the interproximal area after diographical comes out of an emerging surgical technique by comparing in the necrotic bone removal, is presented. same patient and for the same type of bone defect two guided bone regenera- Methods: A 24-year-old male presented with an electrocautery injury on ac- tion techniques. count of the excision of gingival tissue extending into carious lesion between Methods: A 52-years-old patient presented with bilateral edentulous areas in the maxillary right first molar and second premolar. The lost interdental pa- the mandible. Cone beam tomography (CBT), showed a major resorption and pilla area showed ulcerations, exposed bone and gingival recession with se- the necessity of a bone augmentation. Using CBT-based software it has been vere pain. A mucoperiosteal flap was elevated and necrotic bone was removed. possible to obtain a surgical guide and a precise 3-dimensional model of the The pedicle palatal connective tissue flap was planned to achieve soft tissue patient’s jaw using a sterilizable material. Split mouth rehabilitation was per- closure. It is initiated by making a horizontal incision 2 mm from the gingival formed. Four ITI Bone Level Straumann implants were placed using a teeth- margin of the teeth on the mesial side of the defect. After a vertical incision in supported guide in position 3.4, 4.4 (postextractive), 3.6 and 4.6. On the right the canine area, a mucoperiosteal flap was elevated. The pedicle connective atrophic crest, bone chips collected with a scraper mixed with Bio-Oss and tissue containing periosteum was harvested, elevated, and rotated to cover the resorbable membrane have been used. On the left side a corticocancellous bone in the interproximal area. The superficial layer of palatal flap was then allograft block, shaped before surgery on the stereolithographic model of the repositioned and sutured. patient’s jaw, was secured with osteosintesis screws and protected with a re- results: The healing was uneventful with no connective tissue necrosis. One year sorbable membrane. Following a 6-month healing period, a second CBT evalu- follow-up showed approximately 1 mm creeping attachment on the root surface ation was carried out. After complete tissues recovery, two CAD-CAM zirconia and increase in papilla height in comparison with appearance in the third week. bridges were screwed as definite prosthesis. Conclusions: The described surgical approach is advantageous since blood results: The preoperative and postoperative scans were then aligned pair supply is provided from the pedicle, which differs from free connective tissue wise using an iterative closest point algorithm, which allowed for compari- and gingival grafts. The technique, using a rotated pedicle palatal connective son between planned and actual implant positions. All measurements were tissue flap, seems to be a viable treatment approach to achieve primary soft performed using Mimics software (Materialise). Four deviation parameters tissue closure in the maxillary interproximal areas. between each virtual and corresponding actual implant were measured: the mean coronal discrepancy was 0.34 ± 0.29 mm; the mean apical difference was 0.28 ± 0.30 mm; the mean angular deviation was 2.29 ± 1.43 degrees; the mean 133 i using xenografts in 3d Bone reconstruction Surgery. vertical discrepancy was 0.15 ± 0.32mm. The major discrepancy has been given a Case report. by post-extractive implants. With the same software it has been possible to quantify the regenerated bone status. A bone resorption of 15% from the ini- Octavi Ortiz puigpelat (Spain), Marin Lissette Meriño tial volume inserted has been registered for the allograft; 5% portion for the conventional technique. Both the bone regeneration was successfully stable a Objectives: Autogenous bone grafts have been for many years the gold stan- 1 year follow-up. dard in bone regeneration surgery. The use of biomaterials as an alternative Conclusions: The block allograft procedure has shortened surgical time and it is still controversial especially in critical defects such as vertical-horizontal reduced post-operation morbidity. Further research is needed to determine alveolar defects. In such situations Khoury developed 3D bone reconstruction whether the 3D block technique had survival rates equal to the others graft some years ago , where the autogenous cortical blocks serve as buccal and materials in term of long follow-up time. As with any regenerative technique, palatal walls and the space between them is filled with cortical and/or cancel- however, treatment of soft tissue will play a crucial role, and the surgeon must lous autogenous bone particles. This technique has been shown to be a predict- treat it skilfully to achieve success. The implants position has a good corre- able technique for vertical bone augmentation with a low rate of complications. spondence with the presurgical planning. However, the use of this technique sometimes requires a large amount of bone particles to fill such a space. The aim of this paper is to show, through a clinical case, the use and the histological evaluation of a xenograft as an alternative for 135 i intraoral soft tissue regeneration with a tissue filling the space between the blocks during 3D bone reconstruction surgery. engineered metabolic active fibroblast layer Methods: A 35 year old healthy woman was treated in our private office in order to reconstruct a vertical defect of 6 mm in her upper posterior maxillary area. Hans-Joachim Gath (Germany), Martin Heel A 3D bone reconstruction technique was performed using a mandibular block harvested from the mandibular ramus area. The space left was filled with xe- Objectives: Tissue engineering offers the ability to new ways of wound treat- nograft cancellous bone particles (0.25–1 mm). Once the particles were well ment in the oral cavity. Soft tissue defects are often covered with transplants packed, a collagen resorbable membrane of 0.3 mm in thickness was placed witch leave donor site defects. After covering a defect with a transplant the over the particles to prevent soft tissue migration. A 5 month healing period structure of the tissue is different which often results in functional defects. The was left to accomplish bone regeneration. Then, three bone biopsies were taken method of tissue engineering offers now the ability to grow a dermal like tis- from the xenograft area using a 2 mm internal diameter trephine. This trephine sue consisting of living fibroblast. In closed bio reactors juvenile human living served as a drill to prepare the implant site. 3.7 by 10 mm implants were in- fibroblast are seeded on a three dimensional scaffold of resorbable vicryl. In serted in each biopsy. Then, the biopsies were sent for histological evaluation. these settings the cells create a dermal like living tissue which can be frozen at results: High number of vital osteocytes was found in the biopsies as well as -80 degrees Celsius. This tissue can be shipped world wide in a just in time set- large amounts of mineralized bone surrounding the xenograft particles. Simi- ting and than after thawed at 37 degrees transplanted. Then after a short time lar observations were in accordance with those found by Khoury in biopsies the fibroblast get metabolic active. This tissue can be used to cover intra and obtained in areas where autogenous bone particles were used. extraoral defects. The living juvenile fibroblast cells secret a panel of growth Conclusions: Within the limits of this case report we can conclude that the use factors like VEGF (vascular endothelial growth factor), PDGF (platelet derived of xenograft particles can be a good option when the space between cortical growth factor), IGF (insulin like growth factor) and KGF (keratinizing growth blocks is large and large amounts of autogenous particles cannot be obtained factor) all of them substantial in wound healing. As these growth factors are during the 3D bone reconstruction. More controlled and prospective studies secreted from living cells the concentration is physiological and acting for a are needed to determine the effectiveness of such material compared to the prolonged time. autogenous bone particles. Methods: We used the above described living dermal like tissue to cover in- traoral defects resulting from surgical resection of SSC (squamous cell car- cinomas), preprothetic surgery and periodontal surgery. A SSY of the anterior 134 i Block allograft technique vs. standard guided floor of the mouth was resected and would have been reconstructed with a bone regeneration: clinical and radiographical results of a radialis flap. Because of the multiple risk factors of the patient a short op- split mouth guided surgery case report erating time was required. Instead of the radialis flap we covered the defects with the dermal like tissue which was fixed with several sutures to allow the leonardo amorfini (italy), Stefano Storelli, Eugenio Romeo intense contact of the fibroblast with the wound bed. After 10 days the covering36
    • clinical reSearch, clinical StudieSdressing was removed and the defect evaluated. The same protocol was used Methods: A literature search was conducted via PubMed for studies on dentalfor intraoral defects resulting from SSC on the buccal side, for preprosthetic applications of CBCT published between 1998 and 2010. The search revealedsurgery (vestibuloplasty) and for periodontal surgery. a total of 540 results, of which 130 articles were clinically relevant and wereresults: In all cases after 10 days the covering dressing was removed. In all analyzed in detail.cases we could observe a mucosal lining of the defects without sings of scar in- results: The results of this systematic review show the different applications offormation. This was proofed with a biopsy and subsequent histological evaluation CBCT imaging in dental practice. Thirty-six articles (27.7%) related to applica-which showed a normal mucosal structure. Even the resected frenulum result- tions in oral and maxillofacial surgery (OMFS), 33 articles (25.4%) to endodonticing from a defect from a SSC in the anterior floor of the mouth was formed new. clinical applications, 22 articles (16.9%) to clinical applications in implant den-Conclusions: The use of dermal like living tissue to cover intraoral defects has tistry, 15 articles (11.5%) to orthodontic clinical applications, 10 articles (7.7%)several benefits. With this protocol we can avoid donor site defects which result to clinical applications in general dentistry, 8 articles (6.2%) to the temporo-in a shorter operating time. More important to use seems to be the mechanism mandibular joint (TMJ), 5 articles (3.8%) to applications in periodontology andin which these defects heal. Instead of tissue transplanted to the defect we 1 article (0.8%) to CBCT applications in forensic dentistry. 36 articles (27.7%)could see a regeneration of the tissue. This can be explained with continues related to applications in oral and maxillofacial surgery (OMFS), 33 articlessecretion of a panal of growth factors in physiological concentration. The intra- (25.4%) to endodontic clinical applications, 22 articles (16.9%) to clinical appli-oral wet environment seems to be ideal for the metabolic activity of the living cations in implant dentistry, 15 articles (11.5%) to orthodontic clinical applica-cells. The dermal like tissue is integrated during the 10 days of required heal- tions, 10 articles (7.7%) to clinical applications in general dentistry, 8 articlesing time and during this process the three-dimensional scaffold resorbs. The (6.2%) to the temporomandibular joint (TMJ), 5 articles (3.8%) to applicationsdisadvantage of the method is that it is not possible to regenerate devincencies in periodontology and 1 article (0.8%) to CBCT applications in forensic dentistry.in volume. The effect on regenerating bone under these protocol should be Conclusions: The majority of CBCT applications in the practice of dentistry areevaluated. found in the specialties of OMFS, endodontics, implant dentistry and orthodon- tics. Future research should focus on obtaining accurate data regarding the radiation doses of CBCT systems and the clinical use of CBCT applications in forensic dentistry and prosthodontics. 203 i Evaluation Of The Mucograft® Matrix in Coverage CliNiCal rESEarCH, CliNiCal STudiES Of periodontium recessions – pilot Study Marzena dominiak (poland), Dorota Mierzwa201 i Histological analysis Of implants Subjected To immediate Objectives: The aim of successful periodontal recession coverage is to obtainFunctional loading in Single Tooth replacement the maximum percentage of average and complete root coverage (ARC and CRC respectively) of the recession and to achieve superior aesthetics. The aimMauro donati (Sweden), Daniele Botticelli, Vincenzo LaScala, Cristiano Tomasi, of this study was to evaluate the clinical effectiveness of the Mucograft® matrixTord Berglundh (Geistlich Pharma AG Switzerland) in coverage of periodontal recessions after the 6 month follow-up period.Objectives: To evaluate the effect on bone healing of immediate load to im- Methods: Treatment was performed at the Department of Oral Surgery, Wro-plants using human histology. claw Medical University, Poland on 7 patients, aged from 18 to 45 years. InMethods: Thirteen patients received two single implants each; 1 immediately total, 9 teeth, including 8 in the anterior part of the maxilla and the mandible,loaded (test) and 1 control. Biopsies containing the implant and a narrow zone underwent treatment. All subjects had single or double recession (Miller(0.7–0.8 mm) of the surrounding bone were collected using a trephine drill af- class I or II). Procedures were performed using coronally repositioned split-ter 1 month in 9 patients and after 3 months in 4 patients. The biopsies were thickness trapezoidal flap in conjunction with the application of the Muco-processed for ground sectioning and prepared for histological analysis includ- graft® matrix. Recession depth (RD) and width (RW), height of keratinized tis-ing the degree of bone-to-implant contact (BIC %) and the percentage area of sue (HKT), distance from cemento-enamel junction to mucogingival junctionthe peri-implant tissues occupied by lamellar bone and woven bone. The local (CEJ-MGJ), aesthetic index (acc. to Bouchard classification- AE) and averagehuman review board approved the study protocol and prior to enrolment all (ARC) and complete (CRC) root coverage were assessed. Post-surgical com-subjects received information regarding the purpose of the study and signed plications, pocket depth (PD) and plaque index (according to Löe & Silness-an informed consent form. PI1) were also evaluated. Measurements were performed using a calibratedresults: Three implants subjected to immediate load failed to integrate, 2 in periodontal probe (1mm resolution) at the baseline and at 1, 3 and 6 monthsthe 1-month and 1 in the 3-month healing group. Analysis using a multilevel, after surgery.multivariate statistical model demonstrated that while no significant differ- results: The ARC and CRC 6 months after surgery were 84.27% and 55.55%ences in BIC % were found between test and control implants, the percent- respectively. A significant decrease in RD (about 2,35mm), RW, and 60.65%age area of woven bone was significantly larger around the test implants than of HKT (about 1,44mm) increase were noted. There was also a significant de-the controls at 1 and 3 months of healing. The analysis also revealed a high crease in PD and PI1. The CEJ-MGJ distance decreased by only about 1 mm.correlation between compartments (micro and macro-threaded portion) of the Between 3 and 6 months post-surgery, creeping attachment of an averageimplant for both BIC % and bone density and significant variability between value of 0.27 mm was observed. Estimation of the AE revealed improved aes-subjects regarding BIC %. thetics in 5 cases and unchanged aesthetics in 2 cases compared to the pre-Conclusions: It is suggested that immediate loading of implants does not in- treatment condition. In no cases were gingival hypertrophy, scars or distortionsfluence the osseo-integration process, while the density of newly formed peri- noted. The colour and consistency of the gingiva were identical with the neigh-implant bone at such sites appears to be increased in relation to unloaded bouring tissue. The mucogingival line was repositioned to a location similar tocontrol implants. that of the neighbouring teeth. No post-surgery pain was observed in any of the cases (VAS1). Conclusions: The use of the Geistlich Mucograft® matrix in coverage of the202 i applications Of Cone-Beam Computed Tomography periodontal recession is effective, highly predictable and results in a significantin dental practice: a literature review increase in the keratinized gingival width. However, the guidelines for working with the matrix must be observed and obeyed.Mohammed alshehri (Saudi arabia), Hadi Alamri, Mazen AlshalhoobObjectives: This article presents a review of the clinical applications of cone- 204 i role Of COlia1, CalCr and pTHr1 Gene polymorphismsbeam computed tomography (CBCT) in different dental disciplines. in The pathogenesis Of aggressive periodontitis. 37
    • Victoria atrushkevich (russia), Alexander Polyakov, Olga Schagina, Anastasiya tissue metabolism and changes taking place in jaws during the development Zinovyeva, Maria Zyablitskaya of this periodontal pathology. It will also make it possible to increase the ef- ficacy of the treatment of AP, since it includes preparations for the correc- Objectives: The occurrence of aggressive periodontitis (AgP) has increased tion of disturbances of mineral turnover in the complex therapy of generalized significantly. The main pathogenetic factor in AgP is rapid resorption of the periodontitis. alveolar bone. At present the effect of the genes’ parathyroid hormone re- Methods: 173 patients of both sexes (91 females and 82 males) with a diagnosis ceptor type 1 (PTHR1), calcitonin receptor (CALCR) and collagen type I alpha of severe AP were included in the study. The main criterion for including was 1(COLIA1) on the processes of bone tissue renewal in osteoporosis of the axial early onset of disease (18–20 years old). The condition of teeth and periodontal skeleton has been proved. Though jawbones are an essential part of the hu- tissues was estimated by clinical indices. Laboratory assessment of the state man skeleton, we have suggested that the above-mentioned genes could have of mineral turnover included: whole calcium, ionized calcium, parathormone, an effect on the alveolar process remodeling resulting from disturbance of the calcitonin, osteocalcin and resorption marker 946;-CrossLaps. Statistical as- stereospecific binding of a receptor to its ligand (i.e. PTH and/or calcitonin (CT) sessment of the data was carried out using descriptive statistical methods as well as from disorders of bone tissue structure resulting from changes in (Students criterion for two groups of comparison with normal sample). The the amount of synthesized protein COLIA1. Consequently, they may influence critical value of the significant point is taken as p8804; 05. Linear relationship AgP etiopathogenesis. analysis of quantitative traits was carried out with calculation of Pearson coef- Methods: To perform the study, 164 adults aged 22-47 were selected and ficient using the Statistica program, version 6.1 (StatSoft, USA). separated into 3 groups: patients with AgP=48, healthy (H)=64 and random results: In males with AP, periodontal pockets were observed to be deeper population sampling (RPS)=52. Dental examination was carried out according and the level of attachment loss was higher than in females with AP. The se- to hygiene index (HI), papilla bleeding index (PBI), gingival index (GI), clinical verity of periodontal tissue involvement correlated with early onset of the dis- attachment loss (CAL) and teeth mobility (TM). The level of PTH, CT, whole ease. Statistically significant differences in bone turnover indices in patients calcium (Cawh) and ionized calcium (Ca2+ ) in patients with AgP and in the with AP compared with the control group were detected: decrease in calcitonin control group was analysed. Genotyping was performed using PCR (CALCR and (2.4 ± 0.26 ng/l, p‹0.01) and osteocalcin levels (5.30 ± 0.67 ng/ml, p‹0.05), which COLIA1 – MLPA, PTHR1 – AFLP) for all groups. A search was carried out for indicates inhibition of osteoblastic function and hence disturbances of osteo- associations between AgP and VNTR polymorphism PTHR1 (5/6/9 tetranucleo- genesis. A statistically significant increase in the ionized calcium level in blood tide repeats (rs 10533296) and single-nucleotide polymorphisms CALCRC›T in women with AP (1.13 ± 0.02, p‹0.05) versus control indices was observed in (rs1801197), COLIA1G›T (rs1800012). All the trials were performed with the the case of increased parathormone levels (PTH 57.9 ± 3.36 ph/ml). A similar written informed consent of patients and the approval of the Ethics Committee change in the level of calcium homeostasis associated with calcium-regulating of Moscow State University of Medicine and Dentistry. hormones (calcitonin 3.0 ± 0.37 ng/l p‹0.05, parathormone 57.5 ± 6.52 ph/ml, results: The study of periodontal tissues in groups AgP and H resulted in the osteocalcin 5.8 ± 0.93 ng/ml p‹0.05) was observed in males with AP. Correlation following findings: HI-29.41 vs. 21.72, analysis of dependence of severe AP clinical presentation on mineral turnover p=0.002; PBI-1.88 vs.0.81, p=0.001; GI-1.67 vs. 0.53, p=0.01; CAL-5.42 vs. in patients of both sexes with AP revealed an inverse correlation (r=0.8) be- 0.49, p=0.032; TM-1.57 vs. 0.16, p=0.001. The level of PTH was 56.55 vs. 45.63, tween the periodontal bleeding index (PBI) and the level of calcitonin. A moder- p=0.008; CT-2.5 vs. 5.10, p=0.001, Cawh -2.39 vs. 2.03, p=0.006; Ca2+ -1.41 vs. ate direct correlation was revealed between the depth of periodontal pocket 1.08, p=0.008. and the level of parathormone (r=0.4). Genetic analysis revealed significant difference between groups in the occur- Conclusions: In summary, our study has shown that disturbance of calcium rence of alleles (A) and genotypes (G) in the PTHR1 gene between groups: homeostasis characterized by an increase in ionized calcium associated with AgP/H/CSP, where the occurrence for A-5 was 78%, 85%, 65%; for A-6 - an imbalance of indices of calcium-regulating hormones (increase in parathor- 22%, 13%, 34%; for A-9 - 0%, 2%.1%, p=0.002, the occurrence for G-5/5 was mone and decrease in calcitonin) is observed in patients with early onset of 57%,70%,3.8%, for G-5/6 - 39%, 23%,52%, for G-6/6 - 4%, 2%, 8%, for G-6/9 AP. A statistically significant decrease in the osteocalcin level in blood serum - 0%, 5%, 2%, p=0.003; H/CSP differences in occurrence of A/G p=0.007/0.003 is also noted, which confirms inhibition of osteoblasic function and the shift of respectively. the remodelling process towards osteoclastic resorption. Differences in the CALCR gene between groups AgP/H/CSP: the occurrence for A-C was 29%, 14%, 23%; for T - 71%,86%,77%, p=0.001, the occurrence for G-C/C - 13%, 3%, 2%; G-C/T - 32%, 45%, 22%; G-T/T - 55%, 72%, 56%, p=0.003; 206 i impact Of The Method Of Surface debridement the occurrence of AgP/H for A/G p=0.001/0.002 respectively; AgP/CPS for A/G and decontamination On The Clinical Outcome Following p=0.02/0.001 respectively. Combined Surgical Therapy Of peri-implantitis. a randomized Differences in the COLIA1 gene between groups: AgP/H/CSP for A-G-53%, 72%, Controlled Clinical Study. 77%; for A-T-47%,28%,23%, p=0.001, the occurrence for G-G/G -32%,48%, 58%, p=005; AgP/H occurrence for A/G p=0.004/0.005 respectively; AgP/CPS Frank Schwarz (Germany), Narja Sahm, Gerhard Iglhaut, Jürgen Becker occurrence for A/G p= 0.004/0.003 respectively; H/CSP occurrence for A/G p=0.38/0.01 respectively. Objectives: The study aimed to investigate the impact of two surface debride- Conclusions: On the basis of the findings, obtained during relative risk (RR) ment/decontamination (DD) methods on the clinical outcomes of combined sur- estimation, the risk of AgP development increases if there are genotypes C/C gical treatment of peri-implantitis. and C/T of the CALCR gene, genotype T/T of the COLIA1 gene and genotypes Methods: 32 patients suffering from advanced peri-implantitis (n=38 combined 5/6, 6/6 of the PTHR1 gene. supra and intrabony defects) were treated with flap surgery, granulation tis- sue removal and implantoplasty at bucally and supracrestally exposed implant parts. The intrabony aspects were randomly allocated to surface DD using 205 i disturbance Of Systemic regulation Of Bone either i) an Er:YAG laser (ERL) device, or ii) plastic curets + cotton pellets + remodelling in patients With aggressive periodontitis sterile saline (CPS). In both groups, the intrabony component was augmented with a natural bone mineral and covered with a collagen membrane. Clinical Victoria atrushkevich (russia), Ashot Mkrtumyan, Anastasia Zinovyeva, Maria and radiographic parameters were recorded at baseline and after 6 months of Zyablitskaya non-submerged healing. results: Two patients were lost during follow-up. At 6 months, ERL-treated Objectives: Evaluation of the role of hormonal regulation in the functional sites failed to show higher reductions in mean BOP (ERL: 47.8±35.5% vs. CPS: status of periodontal tissues has been receiving attention from researchers 55.0±31.1%) and CAL values (ERL: 1.5±1.4 mm vs. CPS: 2.2±1.4 mm) when for a long time. Aggressive periodontitis (AP) resulting in early tooth loss in compared with the CPS group. Both groups exhibited a comparable radio- young and middle-aged persons is of particular interest. Detailed study of graphic bone fill at the intrabony defect component. skeleton mineralisation peculiarities as well as determination of major in- Conclusions: The study failed to demonstrate any significant impact of the dices of bone formation and bone resorption in patients with AP will make it method of surface DD on the clinical outcome following combined surgical possible to reveal any pathogenetic association between disturbances of bone therapy of advanced peri-implantitis lesions.38
    • clinical reSearch, clinical StudieS207 i autologous Bone Block Grafts From The retromolar region zerland); (ii) Bio-Oss® bearing a calcium-phosphate coating into which BMP-For localized ridge augmentation in The aesthetic zone 2 had been incorporated (130µg/g of Bio-Oss®); and (iii) a mixture of native Bio-Oss® and chips of autologous bone. The heights of the grafts and theirMilan Jurisic (Serbia), Ivan Kosanic, Miroslav Andric, Vladimir Kokovic, Bozidar volumes were estimated by CBCT on 0.3-mm-thick virtual axial sections, priorBrkovic to and immediately after augmentation. Biopsies were taken after 6 weeks, 4 months and 6 months for histological analysis of the implantation site and forObjectives: Adequate bone volume is an essential factor in the long-term suc- histomorphometric estimation of the volume density of newly-formed bone.cess of implant therapy. Localized alveolar ridge deficiency is a common prob- results: Clinically, no differences were observed between the three treatmentlem related to implant placement and has a particular impact on the aesthetic groups in terms of soft-tissue wound healing and complications. Preopera-of implant-supported fixed prostheses. Autologous bone block grafts are con- tively, the mean height of the alveolar ridge was 2.7mm, which was raised tosidered to be the method of choice and the “gold standard” for localized ridge 14.1mm by the augmentation procedure. During the follow-up period, the vol-augmentation in the aesthetic zone. It has also been shown that the quality ume of the graft increased significantly and to a similar degree in each of theand quantity of augmented bone obtained are sufficient for predictable implant three treatment groups. At each of the probing times (6 weeks, 4 months andstability. The purpose of the present study was to examine the integration and 6 months), the stiffness of the augmented bone bed was highest in the groupsvolume maintenance of autogenous bone block grafts and the stability of im- of patients that had been treated either with Bio-Oss® bearing a BMP-2-func-plants inserted following augmentation. tionalized calcium-phosphate coating or with a mixture of native Bio-Oss® andMethods: Eighteen adult patients, 11 male and 7 female, with 20 alveolar de- autologous bone; it was lowest in the group of patients that had been treatedfects who required alveolar ridge augmentation prior to implant placement with native Bio-Oss® alone. This evaluation was clinically determined by twoin the anterior maxilla were included in the study. All patients were aged independent observers. Preliminary histological findings revealed inflamma-between 19 and 47 years. All surgical procedures were performed under lo- tory reactivity at the 6-week juncture to be lowest in the groups of patients thatcal anaesthesia. The approaching incision was of midcrestal type with verti- had been treated either with Bio-Oss® bearing a BMP-2-functionalized coatingcal labial extensions including the papillae. Bone block grafts were harvested or with a mixture of native Bio-Oss® and autologous bone; it was highest in thefrom the retromolar region of the mandible using trephine burrs. The width of group of patients that had received native Bio-Oss® alone. At the same timethe residual ridge was measured by bone caliper at two points 5 and 10 mm point, the volume density of newly-formed bone was highest in the group offrom CEJ of neighbouring teeth, prior to grafting and immediately after graft patients that had been treated with Bio-Oss® bearing a BMP-2-functionalizedplacement. The graft sites were re-opened after 4 months for the purpose of calcium-phosphate coating.implant placement and fixation screw removal. The previously described mea- Conclusions: The CBCT findings and the preliminary histological and histo-surements of the grafted ridge were repeated at the same reference points. morphometric data afford strong indications that BMP-2 elicits no adverse re-Implant stability was recorded by RFA using an Ostell mentor device, at the activity at the site of implantation when it is borne by Bio-Oss® in the form oftime of implant placement and 3, 6 and 12 weeks afterwards. a functionalized calcium-phosphate coating; on the contrary: it acts truly in itsresults: Twenty alveolar defects were grafted and 20 implants inserted in 18 capacity as an osteogenic agent.patients. No complications or failure of bone graft were recorded during theobservation time. Measurement of the horizontal dimension of the residualalveolar ridge (RAR) showed a mean value of 3.06 mm (0–6.0 mm) at 5 mm 209 i Comparison of autologous Full-Thickness Gingivafrom CEJ and 5.84 mm (3.7–10.2 mm) at 10 mm. At the time of graft place- and Skin Substitutes for Wound Healingment, the horizontal dimensions were 6.10 mm (4.3–9.0 mm) and 8.74 mm(6.0–12.0 mm), at 5 mm and 10 mm respectively. There was no significant abraham Vriens (Netherlands), T Waaijman, H.M van den Hoogenband, E.M.dedifference in the horizontal dimension of RAR between the values at the time Boer, R.J.Scheper, S.Gibbsof bone grafting and the time of implant placement. Mean values for initial im-plant stability were 71.25 ± 5,77 ISQ. During the osseointegration period, the Objectives: Ideally tissue engineered products should maintain the character-implant stability obtained (mean ± SD) for the third week was 70.00 ± 4.76 ISQ, istics of the original tissue. The aim of this study was to develop an autologousfor the fourth week 71.30 ± 4.27 ISQ, for the eighth week 72.60 ± 5.55 ISQ and full- thickness gingiva substitute suitable for clinical applications and to com-for the twelfth week 75.00 ± 5.29 ISQ. The statistically significant difference pare it with our autologous full- thickness skin substitute that is routinely usedwas recorded between the value of the initial primary stability and stability at for healing chronic wounds.12 weeks (p‹0.05). Methods: Epithelial sheets and connective tissue fibroblasts are used to con-Conclusions: In the light of the significant implant stability and adequate vol- struct autologous skin and gingiva substitutes. For each 1.5 cm2 of autologousume of alveolar bone obtained 4 months after the augmentation procedure, gingiva substitute to be constructed, a single 3mm biopsy was required. Forthe use of autogenous bone grafts can be suggested as a safe and predictable gingiva this biopsy was obtained from the gingiva distopalatinal to the thirdmethod for successful bone augmentation in the aesthetic zone. molar or adjacent to tooth extraction sites. Epithelial sheets were placed with the most differentiated side upwards on the allodermis and cultured air ex- posed in keratinocyte medium. After approximately 7 days of culturing the pri-208 i augmentation Of The Maxillary Sinus Floor With mary fibroblast culture and epithelial sheet apart, the allodermis containingdeproteinized Bovine Bone Bearing a BMp-2-Functionalized the epithelial sheet was placed in contact with the fibroblasts in order to allowCalcium-phosphate Coating: a pilot Clinical Study fibroblast migration into the reticular side of the dermis. The gingiva substitute was further cultured in DMEM/Hams (3:1). Keratinocyte growth factor (4ng/ml)yuelian liu (Netherlands), Sanja Umanjec-Korac, Daniel Wismeijer, Gang Wu, and 1 ng/ml epidermal growth factor were added to the culture medium forBalsam Hassan the next 7 days. Penicillin / streptomycin was ommited 4 days before applica- tion to the wound. Gingiva substitutes were ready for application 3 weeks afterObjectives: The purpose of this prospective clinical trial was to ascertain removal of the gingiva biopsies from the patient.whether BMP-2 that had been co-precipitated with a layer of calcium phos- results: For gingiva substitute, three patients requiring multiple tooth extrac-phate upon granules of the bone-defect-filling material Bio-Oss® (deprot- tions were included. The gingiva substitute was applied and held into place byeinized bovine bone) could be safely used to promote bone formation in the sutures at one extraction site whereas a second extraction site was allowedcontext of sinus-floor lifting. The height and volume of the grafted materials to heal by conventional second intention healing. Time to 100% healing waswere monitored non-invasively by Cone Beam computer tomography (CBCT); defined by full reepithelialization of the wound and no drainage from the site. Inthe volume density of newly-formed bone was estimated by a histomorpho- all three patients, no rejection of the gingiva substitute occurred. The gingivalmetrical analysis of biopsies. substitute was incorporated into the surrounding gingiva to such an extent thatMethods: Nineteen healthy patients (mean age: 58 years), destined to receive it could no longer be distinguished from surrounding gingiva after 2 weeks. Noa total of 55 dental implants, underwent augmentation of the sinus floor using inflammation was observed and the gingiva substitute was well tolerated. Thethe lateral-window technique. Twenty-nine sinuses were treated according to full thickness gingiva substitute maintained many of the histological charac-one of three different protocols: (i) native Bio-Oss® (Geistlich, Wolhusen, Swit- teristics of the tissue from which they were derived. However the number of 39
    • living cell layers and proliferating cells in the gingiva substitute was clearly results: The average time of the implants in situ was 39.74 months (5.13– less in vitro than in vivo. In the gingiva substitute, fibroblasts populated the en- 82.13) and the average mean loading time was 29.81 months (2.89–70.58). Af- tire dermal matrix, although at a somewhat lower frequency to that observed ter the last check, 58 % showed no horizontal and vertical bone resorption. 41 in vivo(vimentin staining) % showed bone loss of up to three millimetres and only one implant showed Conclusions: The gingiva substitute could be applied to a wound in a single, severe resorption of 75 % of the implant length. Gingival stability was propor- one-step surgical procedure. In the wounds an accelerated and improved heal- tional to bone stability with a rate of 85 %. None of the controlled implants was ing was observed. Our previous findings indicate that the presence of fibro- lost. Therefore the survival rate was 100% and the success rate was 88.2%. blasts in the dermis in addition to an epithelium will stimulate angiogenesis, Conclusions: Due to the long-term stability of the hard and soft tissue after and therefore wound healing, more than a construct containing only a epithe- lateral ridge augmentation with BioOss / BioGide in combination with the An- lium. Even though the number of patients involved in the application is very kylos-Implant system, we can describe this method as predictable and safe. small (n=3) our results represent a large step forward in the area of clinical applications in oral tissue engineering. 212 i Treatment Of Gingival recession defects using Coronally advanced Flap With a porcine Collagen Matrix Compared To 210 i long-term results after lateral ridge augmentation Connective Tissue Graft: a randomized Controlled Clinical Trial using Two different Techniques daniele Cardaropoli (italy), Lorenzo Tamagnone, Alessandro Roffredo, Lorena pablo Hess (Germany), Bergen Pak, Georg-Hubertus Nentwig Gaveglio Objectives: The aim of this retrospective clinical study, performed at the Objectives: Treatment of gingival recessions is usually performed surgically University of Frankfurt, was to investigate the long-term stability of the peri- according to the principles of mucogingival therapy. The use of coronally ad- implant bone and soft tissue after lateral ridge augmentation around Ankylos vanced flap (CAF) together with connective tissue graft (CTG) can produce pre- implants (Dentsply-Friadent, Germany). This study shows the differences be- dictable outcomes in terms of recession coverage, gain of keratinized tissue tween simultaneous and delayed augmentation techniques. It compares the and improvement of gingival thickness. However, the graft harvest may be long-term stability of corticocancelleous bone blocks and pure bovine bone characterised by high morbidity as a result of the need for a second surgical substitute (Geistlich, Switzerland). The results are based on data acquired from site, patient discomfort, post-surgical bleeding and a limited supply of donor a standardized examination sheet, performed at annual checks. tissue. In the last years, alternative procedures to CTG have been evaluated Methods: All the patients who received a lateral ridge augmentation between to limit invasivity and pain. Recently, a porcine collagen matrix (Mucograft, 2001 and 2008 were included. 182 implants were inserted and the clinical and Geistlich [MG]) has been proposed as a soft tissue graft substitute. The aim of radiographic examination was performed on the day of the final prosthetic the present study is to evaluate the use of CAF+CTG (control sites) and CAF+MG treatment and annually thereafter until January 2008. The stability of the peri- (test sites) for the treatment of Miller’s class I single gingival recessions, in a implant bone and the soft tissue was documented and investigated. prospective randomized controlled clinical trial. results: 113 patients, 71 women and 42 men, with an average age of 47 years Methods: A total of 18 adult non-smoker patients (9 males and 9 females, aged (18–73 years) were investigated. In total, 182 Implants were inserted, 107 in the 21 to 59 years [mean age 41.39±10.02 years]) were included in this study. The maxilla and 75 in the mandible. The survival rate of the implants was 100%. The patients, all systemically healthy without contraindication to periodontal sur- success rate for all implants, as defined by Albrektsson and Zarb1, was 93%. The gery, presented 22 single gingival recession defects, classified as Miller’s class average time of the implants in situ was 40.99 months (range 7.8–82.1 months), I. The defects were randomly assigned by coin toss to the control or test sites, the average mean loading time was 31.42 months (range 2.9–71 months). until eleven defects were selected for one of the two groups. The test group At the final recall, 109 (60%) of the implants showed no vertical and horizontal received CAF+MG, while the control group received CAF+CTG. bone resorption, only 1 implant showed a maximum vertical resorption of 4.5 Clinical measurements were recorded using a calibrated UNC 15-mm periodon- mm, and 1 implant showed a resorption of 5 mm. 157 (86.2%) of the implants tal probe and were rounded to the nearest 0.5 mm. At baseline and 12 months showed no gingival recessions. post-surgically, the recession depth (REC), probing pocket depth (PPD), clinical Conclusions: The peri-implant bone and soft tissue showed constant long- attachment level (CAL) and width of keratinized tissue (KG) were recorded. In term stability in both groups. Due to the high success rate of lateral ridge addition, the gingival thickness (GT) was measured at a buccal location 1 mm augmentations with the augmentation methods examined, in combination with apical to the bottom of the sulcus using a no. 15 reamer endodontic instrument. the Ankylos-Implant system, we can describe both methods as predictable and results: All the clinical parameters were statistically evaluated at baseline and safe. Each technique has individual indications, depending on anatomical con- after 12 months, using the t-test for both the intra-group and inter-group analy- ditions and the surgeon’s experience. ses (statistical significance with p‹0.01). At baseline, REC depth was on average 3.09 mm for the test sites and 3.05 mm for the control sites. At 12 months, mean REC was 0.23 mm for the test sites and 0.09 mm for the control sites. At 1 year, 211 i periimplant Bone and Soft Tissue Stability after lateral the percentage of root coverage was 92.55% in the test group and 97.04% in the ridge augmentation using Bovine Bone Substitute – retrospective control group. The REC reduction was statistically significant for both groups. No Clinical Study difference was found between the sites treated with CAF+MG and those treated with CAF+CTG. No differences were found in PPD among or between the groups. Bergen pak (Germany), Pablo Hess, Georg-Hubertus Nentwig CAL gain was statistically significant for the intra-group analysis, without any difference between the groups. At baseline, KG mean value was 2.23 mm for the Objectives: The aim of this retrospective clinical study was to evaluate the long test sites and 2.05 mm for the control sites. After 12 months, KG increased in term stability of the peri-implant bone and soft tissue around dental implants. average to 3.45 mm in the test group and to 3.32 mm in the control group. The in- To increase the significance of the results, the study was performed with only crease in KG from baseline to 12 months was similar for the CAF+MG and for the one implant system and one bone substitute. CAF+CTG group, without any inter-group statistical difference. Both treatment Methods: The results are based on data acquired from a standardised ex- sites experienced a statistically significant increase in GT from baseline to the amination sheet, performed at annual checks. All the patients who received 1-year evaluation (p‹0.01). At the test sites, GT varied from 0.82 mm to 1.82 mm a lateral ridge augmentation with bovine bone substitute (BioOss, Geistlich, after 12 months. At the control sites, GT varied from 0.86 mm to 2.09 mm after 12 Switzerland) and simultaneous implantation (Ankylos, Dentsply-Friadent, months. The difference between the groups was not significant. Germany) between 2001 and 2008 were examined. The follow up period was Conclusions: Within the limits of the study, CAF+MG achieved clinical outcomes seven years (2001 to 2008). 76 patients, 54 women and 22 men with an aver- similar to CAF+CTG in terms of root coverage, CAL gain, KG gain and GT im- age age of 51 years (range 18 to 73) were included in this study. 127 implants provement at the 12-month evaluation. Both procedures offered a predictable were inserted. The clinical and radiographic examination was performed on means of treatment for gingival recessions in Miller Class I. The collagen ma- the day of the final prosthetic treatment and annually thereafter until Janu- trix represents a viable, simple and convenient alternative to connective tissue ary 2008. graft, reducing the morbidity associated with tissue harvesting at the donor site.40
    • clinical reSearch, clinical StudieS213 i Bio-Oss and Stem Cells From Bone Marrow ridge atrophy in the retromolar area was observed in 8 patients over 5 years ofObtained From The distal Femur For Sinus Grafting observation. The degree of atrophy measured by tooth height correlates with intensive smoking habits (r=-0.54, p‹0.05), daily use of alcohol (r=-0.39, p‹0.05)Juan Carlos ibañez (argentina), Ruben Sambuelli, Maria Agustina Juaneda, and low calcium diet (r=-0.36, p‹0.05). In 17 cases of root preservation and 45Maria Constanza Ibañez, Jose Monqaut cases of tooth crown, preparation with reverse retention was carried out and the standard implantation procedure was performed on the basis of sufficientObjectives: Sinus grafting has become a common procedure for obtaining ad- alveolar ridge size (width 6.3±1.7 mm, height 12.0±0.8 mm). In the retromolarequate height for implant placement in the posterior maxilla. High success or area the volume of alveolar plate was insufficient in 3 cases and artificial graftsimplant survival rates, reduction of healing time and obtaining of a high per- were used.centage of vital bone may be primary objectives when this technique is applied. Conclusions: The results of this study suggest that the reverse tooth reten-This investigation was designed to test whether the combination of Bio-Oss tion method can be used successfully before implantation or other prostheticgrafting material and bone marrow obtained from the distal femur with high procedures.concentrations of stem cells is able to be used for sinus grafting in order toobtain high success/survival rates and high percentages of vital bone.Methods: Twelve sinus grafting procedures were performed in seven patients. 215 i The Effect Of adult MSC On Bone regenerationResidual bone width and height were measured. All the procedures were per- Following a Sinus augmentation procedureformed using a lateral approach with piezo surgery. Ten to fifteen cc. of bonemarrow with stem cells was obtained from the distal femur using an appro- angelika Wildburger (austria), Michael Payer, Robert Kirmeier, Stefan Tangl,priate trocar and aspirated with a syringe without any anti-coagulants. After Birgit Lohbergereliminating the excess plasma, the bone marrow was mixed with Bio-Oss (largespongious particles) and used to fill the space obtained by elevation of the sinus Objectives: The overall aim of methods of alveolar ridge regeneration is themucosae. The lateral window was covered with resorbable membranes. After introduction of efficient, minimally invasive techniques allowing successful im-6 to 9 months of healing, 24 double acid-etched surface implants were placed. plant rehabilitation in order to avoid the harvesting of autogenous bone graftsRFA analysis was used to measure initial stability. Six implant sites were created and to reduce donor site morbidity. Mesenchymal stem cells (MSCs) have beenwith 3.5 mm. trephines in order to obtain vertical biopsies for histological and considered as promising tools for tissue engineering approaches. Severalhistomorphometric analyses. After four to six months the implants were loaded. studies show low postoperative morbidity (Kirmeier et al 2007) and high mes-results: All the sinus procedures healed uneventfully. Twenty-two implants enchymal stem cell counts in bone marrow aspirate from the proximal tibia (M.were successful and a mean of 42% of vital bone was obtained at the time of Payer et al., EAO Zürich 2006, Krems 2006/ poster presentations).implant placement. The mean ISQ obtained at implant placement was 62.3 and The aim of the present clinical pilot study was to assess whether a non-con-60.8 at implant loading. centrated bone marrow aspirate from the proximal tibia showed positive ef-Conclusions: The results of this preliminary report show that the use of a mix- fects when mixed with a xenogenous grafting material (BioOss®).ture of Bio-Oss with bone marrow obtained from the distal femur seems to be Method: For this pilot study, 6 patients with severely and symmetrically re-an efficient combination for obtaining an adequate percentage of vital bone sorbed (‹ 3mm) alveolar ridges in the posterior maxilla and requiring implantwhen sinus lifting is performed and for obtaining good results when implants treatment were included. A bone marrow aspirate (approx. 10ml) from thewith microtextured surface are used. proximal tibia was harvested during the bilateral sinus augmentation proce- dure. At the randomly selected test site the BMA was added to the bone substi- tute (porous bovine bone mineral, BioOss®). At the control site the augmenta-214 i Teeth Height preservation By Means Of reverse tion procedure was performed with the bone substitute only.Tooth retention Method Biopsies were taken from both sites 3 and 6 months after bone augmentation and analysed by means of histomorphometry.Mykhailo kasiyanchuk (ukraine) results: The histomorphometric analysis did not reveal any significant effect of the bone marrow aspirate. After 3 months of healing there was a mean bone toObjectives: Tooth loss due to trauma or periodontal disease is often associated bone substitute contact (BSC) of 15.06% (SD 12.52) and a mean new bone for-with atrophy of the alveolar ridges. Due to atrophy the final volume of bone mation in the total volume of the biopsy (NB) of 9.45% (SD 4.15) in the controltissue and the height of bone ridges are insufficient for dental implant place- group, whereas in the test group the mean BSC was 13.67% (SD 17.93) and thement. The preservation of alveolar ridge dimensions and bone characteristics mean NB was 10.36% (SD 11.83). After 6 months of healing there was a meancould be more effective than any augmentation methods. Augmentative bone bone to bone substitute contact (BSC) of 17.89% (SD 9,63) and a mean newtreatment may result in extensive surgical interventions and increased treat- bone formation in the total volume of the biopsy (NB) of 10.41% (SD 5,25) in thement costs. Attempts to reduce alveolar bone resorption include the place- control group, whereas in the test group the mean BSC was 20.26% (SD 11,32)ment of natural roots, root analogues and immediate implantations into the and the mean NB was 11.81% (SD 6.62).extraction socket, sometimes in combination with membrane or graft tech- Conclusions: There was considerable variability in the results for a small groupniques and other restorative techniques. The aim of this study was to evaluate of patients. No significant effect of bone marrow aspirates could be detected inthe effectiveness of reverse tooth retention methods in alveolar bone volume our study. Larger studies are certainly needed and it would be interesting to seepreservation. whether a concentrated bone marrow aspirate would produce better results.Methods: Materials and methods: The study included 65 consecutive patientspresenting beaked teeth or their roots after trauma or periodontal diseasewith atrophy beginning. The author’s own method of reverse tooth reten- 216 i Subepithelial Connective Tissue Graft intion (Ukraine patent U200612) was performed in all cases. According to this The Treatment Of adjacent Gingival recessionsmethod, the treated roots or the remains of the processed dental crown werecovered with gum flap sometimes in combination with membrane. The site was Cosmin Cioban (romania), Alexandra Roman, Andrada Soanca, Radu Campian,treated with red ray laser. The height of the alveolar bone ridges and the height Daniela Condorrequired for insertion of the appropriate implants were calculated in each pa-tient after X-ray or CT evaluation. Objectives: Coronally advanced flap (CAF) associated with a subepithelial con-results: Results. Stable marginal bone conditions can be preserved after 1–8 nective tissue graft (SCTG) has been successfully used as a “gold standard”years following reverse tooth retention. Laser illumination for several days procedure in the treatment of recession-type defects. The aim of this study wasafter operation prevents some acute complications. Follow-up observation to evaluate the clinical outcomes when using a CAF associated with SCTG forof patients showed a mean marginal bone loss of 1.2 mm (SD 0.8 mm) dur- root coverage of Miller class 1 adjacent recession defects.ing the period. Vertical resorption in the frontal area was 1.4±0.5 mm in the Methods: Twelve patients (5 males and 7 females), ages 21 to 44 years (meanmolar area. Horizontal resorption was absent after 3 years, after 5 years it age, 30.76±7.29 years), non-smokers, were recruited for the study from thewas 1.7±0.7 mm and after 8 years 1.6±0.9 mm. The absence of any alveolar Periodontology Department of the Iuliu Hatieganu University of Medicine and 41
    • Pharmacy in Cluj-Napoca, after giving informed consent. The study protocol Objectives: The aim of this prospective pilot clinical trial is to evaluate the was approved by the University’s ethics committee. All patients were suffering prosthetic advantages offered by CT-guided implant surgery in patients who from 2 adjacent gingival recessions classified as Miller’s class I and requested have undergone jaw reconstruction with free flaps, following resection for tu- surgical root coverage procedures. Clinical measurements were taken by the mours, firearms traumas or severe atrophy same periodontal specialist immediately before the surgical treatment and 3, 6 Methods: 15 patients who had undergone free flap maxillary or mandibular and 12 months after surgery. Measurements included recession height, prob- reconstruction were selected from among 47 reconstructed patients. At the ing depth, clinical attachment level and width of the keratinized tissue. All sur- present date, 7 consecutive patients of both sexes have been treated, with a gical procedures were performed by the same surgeon, who was not involved sufficient follow-up period (6 months after loading, at least). Prosthetic resto- with the clinical measurements. Data analysis was performed with SPSS 16 ration was performed according to a modification of the standard NobelGuide using the Friedman non-parametric overall statistical test. protocol (Procera Software; Nobel Biocare). Computer assisted, dental im- results: Among 12 patients, 24 recessions were evaluated and treated. All plant placement was based on accurate prosthetic and aesthetic analysis. The surgical procedures were well tolerated by the subjects and no postoperative standard NobelGuide protocol had to be modified due to the need to adapt the complications were observed. The results obtained after 3 month showed a standard technique to these reconstructed patients. A total of 36 fixtures were coverage rate of 66.67% to 100% (mean 95.14%); in 20 recessions (83.4 %) the installed (Replace Tapered Groovy Nobel Biocare). The implant lengths ranged coverage yielded 100%. The rates of coverage at 6 and 12 months post-surgery between 8 and 16 mm; the implant diameters were 3.5, 4.3 or 5 mm. The ranged from 75% to 100% (mean 97.9 %); 22 recessions (91.6 %) were covered implants were loaded immediately or after six months, with screw-retained completely. The width of keratinized tissue (KT) before the surgery ranged from prostheses. Clinical and radiological follow-up was scheduled at 3, 6,12 and 18 2 to 4 mm (mean 2.6 mm) and at 6 and 12 months post-surgery ranged from 3 months after surgery. to 5 mm (mean 3.9 mm). results: All seven treated patients were followed up for at least 6 months Conclusions: Surgical treatment using SCTG in combination with CAF tech- (range 6–18 months). Two implants were lost during the healing period (CSR nique resulted in significant root coverage of class I multiple recessions. An 94.5 %). Every patient received a correct provisional prosthetic rehabilitation increased width of keratinized tissue was observed after the surgery. Acknowl- with a high degree of satisfaction in terms of masticatory function, social func- edgements: This study was supported by the Romanian Ministry of Education tioning and overall quality of life. Radiological rough estimation of bone level and Research, CNCSIS Grant No.1341. showed a stable marginal bone level. No other complication, biological or me- chanical, has so far been recorded. Conclusions: Implant-based dental restorations provide many advantages in 217 i postoperative Complications Following Gingival Grafts: free flap reconstructed jaws. Unfortunately, implant planning can led to many a prospective Cohort Study problems in these difficult patients. We believe that these complications can be reduced by adopting prosthetic-guided, computer-assisted implant surgery. daniela Condor (romania), Alexandra Roman, Robert Balazsi, Radu Campian, These preliminary results suggest that the protocol presented here should be Cosmin Cioban adopted in order to achieve the best prosthetic restoration for these difficult reconstructions. Objectives: The aims of this study were 1) to evaluate the postoperative com- plications after free gingival graft (FGG) and connective tissue graft associated with coronal advanced flap (CGCAF) used to cover GR and 2) to compare the 219 i Surgical Technology For reconstruction intensity of these complications between the two techniques. Of Mandibular radionecrosis using Calcium phosphate Methods: Seventeen patients were recruited from the Periodontology Depart- Bioceramics and Total Bone Marrow ment of Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca. Eleven FGG and ten CGCAF procedures were performed by a single experi- Guy daculsi (France), Franck Jegoux, Olivier Malard enced practitioner in order to cover GR,. Patients were asked to fill out a ques- tionnaire 14 days after the surgery, evaluating postoperative pain, swelling and Objectives: Treatment of oral carcinomas usually requires surgical removal bleeding. Each symptom was evaluated using a 1 to 10 visual scale, where 1 followed by radiotherapy. Since tumors are frequently bulky, bone is often represented the absence of the symptom and 10 the most intense manifesta- involved and the surgical procedure requires major resection. Free flaps still tion. Given the small sample size, the data were analyzed using parametric (in- constitute the gold standard in mandibular reconstruction. Complications lead dependent sample t-test) and non-parametric techniques. We also computed to the need to investigate alternative therapies. Cohen’s d effect size coefficient. Since bone graft and bioceramics alone have failed, adjunction of osteoin- results: Every patient experienced at least one minor complication. The pa- ductive properties has been investigated. Total bone marrow graft use has tients experienced more pain in the grafted area than in the donor area, for been investigated in animal and in human clinical applications. We have re- both surgical techniques, with a mean value of 3.09 (1.3 sd) versus 2.27 (1.4 cently proposed the concept of an immediate post-radiation bone marrow sd) for the CGCAF group and of 3.7 (2.21 sd) versus 2.9 (1.7 sd) for the FGG graft to provide an osteoinductive potential to the ceramic with good results. group. Generally, the effect size for all measured variables reached at least According to this data, a pilot study promoted by Nantes and Rennes Hospi- the medium level (d=0.33-0.91); CGCAF generated higher scores on the scale tal ENT department was in progress in humans to determine a bone tissue of unpleasantness. The only statistically significant difference between the two engineering approach to patients presenting mandible cancer-related bone techniques was recorded for tumefaction: mean 2.45 (0.93 sd) for FGG and defects. mean 4 (2.21 sd) for CGCAF, t value being 2.12 (p‹0.05). Methods: Animal experiments were realized in the Nantes National Veterinary Conclusions: In contrast to existing evidence, our results showed that CGCAF School (Oniris) in compliance with European directive number 86/609/CE. The was associated with more severe complications than FGG, even if the differ- study was conducted in accordance with animal experiment ethics rules. Two ence was significant only for tumefaction. In view of the fact that the proce- cm segmental defects were created in the femoral diaphysis of New Zealand dures were all carried out by the same practitioner, the specific psychological rabbits, and a femoral critical size defect in a canine model. attributes of the patients may have influenced the results. Acknowledgements: Clinical study: curative technology of radionecrotic mandibular bone defect. Mul- This study was supported by the Romanian Ministry of Education and Re- ticentric study, Nantes Hospital promotion (ID RCB: n°2008-A01593-52; Ref BRD search, CNMP Grant No. 42141 and CNCSIS Grant No. 1341. 08/10-H). Clinical trial phase 1, non randomized, Bicentrique Nantes-Rennes. This involved ten patients with osteoradionecrosis with surgical ablation, and with the basilar mandibular cortical bone preserved. 218 i large Soft and Hard Tissues Jaw defects. results: Successful osseous colonization was found suggesting an osteoinduc- Computer assisted implant Surgery in Microvascular Free Flaps. tion role of the bone marrow graft in the center of the defect after radiotherapy. prospective Clinical Trial. According to this data, a pilot study promoted by the Nantes and Rennes Hos- pital ENT department was in progress in humans to determine a bone tissue Silvio Mario Meloni (italy), Giacomo De Riu, Milena Pisano, Olindo Massarelli, engineering approach to patients presenting mandible cancer-related bone Elena Carta defects. Clinical follow up revealed no adverse effects and high architectured42
    • clinical reSearch, clinical StudieSbone regeneration. Some patients showed limited side effect related to insuf- were augmented with BBM and BMAC containing mesenchymal stem cells.ficient soft tissue reconstruction. In spite of the newly formed bone exposure, Eleven control sinuses from 11 patients were augmented with a mixture of 70%the bone regeneration was maintained. BBM and 30% AB. Biopsies were obtained after 3–4 months healing period atConclusions: This pilot study demonstrated the efficiency of total bone mar- the time of implant placement and histomorphometrically analyzed for NBF.row combined to synthetic bone graft (MBCP+®) for bone regeneration in low results: NBF was 14.3±1.8% for the control and non-significantly lower attrophic areas, particularly for radionecrotic bone defects. 12.6±1.7% for the test (90%-CI-interval -4.6 1.2). Values for BBM of 31.3±2.7%Our findings demonstrate that a micro macroporous CaP bioceramics bone were significantly higher for the test compared to control of 19.3±2.5%graft followed by post-radiation can be revitalized using a total autologous (p‹0.0001). Non-mineralized tissue was lower by 3.3% in the test compared tobone marrow graft. This has significant implications for the bone tissue en- control (57.6%; p=0.137).gineering approach to patients with cancer-related segmental bone defects. Conclusions: NBF after 3–4 months is equivalent in sinus, augmented with BMAC and BBM or a mixture of AB and BBM. This technique could be an alter- native to using autografts to stimulate bone formation.220 i Vestibuloplasty By Means Of a resorbable CollagenMembrane Versus The autogenous Split Thickness Skin Graft.preliminary results Of a prospective randomized Trial. 222 i Management Of Severe Maxillofacial Trauma using a Nonvascularized iliac Crest Bone Graft and CadCaM-facilitatedChristian Tudor (Germany), Katrin Kiener, Christian Schmitt, Falk Wehrhan, Osseointegrated implant prosthodonticsFriedrich Wilhelm Neukam andrew Barber (Great Britain), Paul HR Wilson, Ceri W HughesObjectives: Split thickness skin grafts are considered to be the method of choicein covering large intraoral defects. Donor area morbidity as well as limited differ- Objectives: This clinical case report describes, illustrates and discusses theentiation to mucosa resulting in an insufficient base for dentures are motivating maxillofacial and prosthodontic management of a patient who was involved in afactors in the development of collagen-based substitutes for intraoral mucogin- severe road traffic accident which resulted in his mandible sustaining commi-gival regeneration. The aim of this in vivo study was to evaluate the suitability of nuted fractures. The clinical procedures involved, evidence base for the treat-a biodegradable, bovine collagen I/III membrane (Mucograft) as a gingival sub- ment strategy and improvements in quality of life are discussed.stitute in surgical vestibuloplastic procedures compared to split-thickness skin Methods: The patient’s chin hit a security barrier while he was travelling at highautografts. Of particular interest were the formation of keratinized gingiva along velocity in a racing car. He was almost decapitated. In hospital, his injuries werethe alveolar crest and shrinkage of the area of gained attached gingiva. imaged. Severe comminution of the left mandibular body necessitated resectionMethods: To evaluate the outcomes in the use of this membrane as a gingival and provisional reconstruction with a titanium osteosynthesis plate.substitute we carried out a prospective randomized trial. Conventional upper and lower complete dentures were poorly tolerated second-Operative vestibuloplasties have so far been performed in 20 patients using the ary to facial nerve weakness and left-sided paraesthesia of the trigeminal nerve.collagen membrane or split thickness skin grafts, respectively. Evaluation took The left mandibular body was reconstructed with a nonvascularized iliac crestplace after 10, 30 and 90 days. bone graft. Four months later, five endosseous titanium implants were placedWe performed photographic documentation as well as three-dimensional scans using a submerged protocol.intraoperatively and at the end of the follow up time measured the covered ar- 4 months later, the implants were exposed via second stage surgery, and de-eas and the depth of the vestibulum. The formation of keratinized gingiva was finitive abutments placed. The prosthodontic phase of treatment involved theshown intravitally by staining with Lugol`s solution and histologically (HE stain- use of a mandibular CAD-CAM titanium overdenture bar (CEKA). An upper con-ing) as well as immunohistochemically (Cytokeratin 5/6) in biopsies that were ventional removable prosthesis and lower overdenture implant were providedharvested from the area of the covered alveolar crest 90 days after surgery. to complete the rehabilitation.results: Performance of the surgical procedures was uneventful in both results: At the end of reconstructive maxillofacial and prosthodontic treat-groups. We found no complications such as wound infection or rejection of the ment, the patient’s quality of life had improved dramatically in terms of speech,transplants or the implants, respectively. Operating time was significantly re- mastication, swallowing and appearance. His quality of life had quantitativelyduced by using the collagen membrane (ø 56 min vs. ø 88 min). After 90 days increased as demonstrated by favorable changes to his OHIP EDENT quality ofwe found comparable shrinkage of the gained area of attached gingiva and the life instrument scores.initially gained vestibular depth in both groups. It measured 59% with the use Conclusions: The maxillofacial-osseointegrated implant prosthodontic recon-of membranes vs. 62% with the use of skin grafts compared to the initially struction of a patient with severe maxillofacial high velocity trauma resultingcreated neovestibulum. These differences showed no statistical significance. in comminuted fractures to the mandible is described. The clinical procedures,Clinically, we found presence of keratinized epithelium along the alveolar crest case management, evidence base behind the treatment and quality of life im-in all subjects belonging to both groups. This could be proved by histological plications are described, discussed and illustrated.and immunohistochemical examination of the harvested biopsies.Conclusions: Taken altogether, we found significant reduction of the operationtime and no donor morbidity with the use of the collagen membrane in com- 223 i Bio-Oss Materials in periodontal regenerationparison to the use of the split thickness skin graft in the described procedure. in Organ Transplant patientsBoth techniques led to the formation of favorable keratinized epithelium alongthe alveolar crest. peter augustin (Czech republic), Antonin Fassmann, Lydie Izakovicova Holla, Jan Vokurka, Hana Poskerova221 i Bone Marrow Concentrate and Bovine Bone Mineral Objectives: Organ transplant patients are successfully treated by complex im-For Bone regeneration in a Clinical Setting munosuppressive therapy. Drug induced gingival overgowth (DIGO) is an unde- sirable side effect of this therapy. Relevant drugs inducing DIGO are CyclosporinSebastian Sauerbier (Germany), Daniela Rickert, Felix Koch, Wilfried Wagner, A, Azathioprin, Mycophenolate, Verapamil or Nifedipine. Many other etiologicalRalf Gutwald factors are involved in causing it and it is worsened by oral biofilm accumulation. Fibrosis, inflammation and cell accumulation depend on dosage, time and typeObjectives: To evaluate the potential of substituting autogenous bone (AB) by of drug administration, oral hygiene and the individual reaction of the organism.bone marrow aspirate concentrate (BMAC). Both AB and BMAC were tested Methods: I used my own classification for DIGO. I plumbed periodontal pocketin combination with a bovine bone mineral (BBM) for their ability to cause new depth by using a WHO periodontal probe. I measured each tooth at 4 differentbone formation (NBF) in a multicentric, randomized, controlled, clinical and his- places (vestibular, mesial, oral and distal) and determined average values. 0 -tological non-inferiority trial. no signs of GO, depth of periodontal pocket 0.5 mmMethods: 45 severely atrophied maxillary sinuses from 26 patients were evalu- 1 - GO is localized to interdental papilla, depth of sulcus is 0.5 mmated in a partial cross-over design. As a test arm, 34 sinuses of 25 patients 2 - GO to 1/3 of clinical crown, 3 GO to 2/3 of clinical crown, 43
    • 4 - GO more than 2/3 of clinical crown or covering whole clinical crown. After healing following augmentation using a natural bone mineral (NBM) and ran- supra and subgingival treatment (SRP) we carry out gingivectomy. Six month domized application of either a cross-linked- (VN) (n=12 patients), or a native later, we perform regenerative periodontal therapy by tissue engineering with collagen membrane (BG) (n=12 patients). RDL values were classified as absent deproteinized bovine bone matrix (DBBM) and platelet rich plasma (PRP). After (0 mm, control; n=8), minimal (1 mm, test 1; n=8), or advanced (› 1 mm, test 2; activation by thrombin and calcium we make composite gel for implantation n=7). Clinical parameters (i.e. bleeding on probing - BOP, probing pocket depth into periodontal defects. This gel is covered by resorbable double collagen - PD, mucosal recession - MR, clinical attachment level - CAL) were recorded membrane. Degranulation of thrombocytes and release of growth factors sig- (mesio-, mid-, and disto-buccal aspects) at 4 years after prosthesis installation nificantly improve quality of periodontal regeneration. by one blinded and calibrated examiner. results: GHI values on average were 1.4 in men and 1.7 in women. Resorption results: Mean BOP (43.7±35.6%, 52.1±35.0%, 40.5±34.5%), PD (2.9±0.7 mm, of alveolar bone was ¼ of dental roots (RTG index was 1.45 in men and 1.14 in 2.8±0.7 mm, 2.7±0.9 mm), and CAL (3.1±0.9 mm, 3.3±0.8 mm, 3.2±1.3 mm) values women). GO in patients with endosteal dental implants and necessity of pre- at 4 years were comparable in all groups investigated (i.e. control, test 1 and test prosthetic correction of soft tissue. I examined 3 patients with endosteal dental 2; respectively). Mean MR values tended to be higher in the test 1 and 2 groups implants. All of them were surgically treated by gingivectomy. Involvement of (0.5±0.7 mm, 0.5±0.6 mm; respectively), when compared with the control group interdental papilla in the frontal area of the upper and lower jaw was noted. (0.2±0.4 mm). However, these differences did not reach statistical significance. Daily dosages of the drugs: Sandimmun neoral (Cyclosporin A) 2–15 mg/kg/ Conclusions: The present long-term follow up failed to reveal a significant im- day, Cellcept (mycophenolate) 2000 mg per day, Immuran (azathioprine) 3 mg/ pact of RDH on peri-implant health. However, RDH values may be associated kg/day and Prograf (tacrolimus) 0.1-0.3mg/kg/day. with an increase in mucosal recession and therefore compromise the overall Conclusions: Poster clearly demonstrates utilization of this method in patients esthetic outcome of implant therapy. after transplantation of the heart and kidney with medication induced peri- odontitis. This therapeutic practice was very acquitted. 226 i prevalence Of peri-implant diseases associated With The TiOblast (TM) dental implant 9 years after insertion 224 i Vertical Changes after autogenous Onlay Bone Graft On posterior Maxilla Julia karbach (Germany), Peer Wolfgang Kämmerer, Karl Martin Lehmann, Victor Palarie, Joachim Wegener Sunjong kim (korea), Myung-Rae Kim Objectives: Peri-implant diseases are compromising implant success and sur- Objectives: In spite of the rapid advancement of the implant surgical technique, vival. Data on the prevalence of peri-implant diseases are rare. A clinical evalu- implant installation on insufficient posterior maxillary bone still remains as ation of the long-term prevalence of peri-implant diseases (mucositis, peri-im- a significant limitation. Guided bone regeneration, distraction osteogenesis, plantitis) of the TiOblast dental implant (Astra Tech, Sweden) was conducted. onlay bone graft and sinus augmentation have been introduced to solve this Methods: A total of 237 implants were inserted in 47 patients (mean age 57 problem. Onlay bone graft has the advantage of solidity, can be used widely years (17-77; standard deviation (SD: 9.6); male n=25, female n= 22) between for maintaining bone contour and aiding the stability of the reconstruction site 1994 and 2005. In a clinical examination after a mean time of 9.12 years (5- even though it shows reduced capability of osteogenesis and slow revasculiza- 12; SD 1.3) after insertion, implant related peri-implantary parameter (plaque tion compared to other bone graft methods. index (PI), sulcus bleeding index (SBI), pocket depth (PD), bone loss (BL) in Methods: A consecutive retrospective study was performed on patients who relation to time of insertion were evaluated. A classification into healthy tissue, had onlay bone grafts for augmentations of severely atrophied maxilla followed mucositis and peri-implantitis was conducted. by placement of implants at Ewha Womans University from 2002 to 2009. Study results: PI, SBI, PD and BL of implants are given in figure 2a-c. 211 implants involved the following investigations: (89%) were seen to be healthy, in 21 implants (8.9%) mucositis and in 5 cases 1. Analysis of vertical height changes after autogenous block onlay bone graft (2.1%, figure 3) peri-implantitis was diagnosed. Evaluated risk factors for peri- on maxilla. implant diseases were alcohol abuse, irradiation and female gender (figure 4). 2. Analysis of peri-implant marginal bone changes of autogenous bone graft 79% of patients with healthy tissue, but only 66% of patients with mucositis on maxilla. and 20% of patients with peri-implantitis were making regular control visits. Bone graft and implant installation was performed by one operator, and MKIII®, Conclusions: After a mean time of 9.12 years, the TiOblast (TM) dental implant ReplaceSelect® (Nobelbiocare, Sweden),USII®,SSII® (Osstem, Korea)were used shows a marginal rate of peri-implant diseases. Even with the low number for implantation. For statistic evaluation, ANOVA analysis and t-test were used. of implants with surrounding mucositis and peri-implantitis, the risk factors results: 1. In autogenous onlay block bone graft on maxilla, mean augmentation alcohol abuse, prior irradiation and female gender could be evaluated. Addi- height was 6.22 mm. Mean resorption of grafted bone was 0.54 mm (8.5%) at 3 tionally, the need for regular control visits with supportive follow-up care has months after surgery, 0.99 mm(15.9%) at 6 months after surgery, so r 2. The loss shown to be important for success rates of dental implants. of peri-implant marginal bone grafted from ramus subsequently increased in the premolar area followed by the molar and anterior area, while the iliac bone graft in anterior maxilla resulted in higher resorption than in the molar area. 227 i a 2-year prospective Clinical and radiographic Conclusions: The rate of resorption was greater at 3 months after surgery than Study Of implants placed after Maxillary Sinus augmentation that between 3 to 6 months after surgery. And results showed resorption of iliac With Bovine Hydroxyapatite bone was larger than that of ramal bone with statistical significance. The mar- ginal bone resorption of the iliac graft was significantly larger than that of ramus. Tommaso anello (italy), Alessandro Rossi, Luigi Tagliatesta, Laura Serioli, Matteo Chiapasco 225 i impact Of The Outcome Of Guided Bone regeneration in de- Objectives: The aim of the present study was to evaluate success and survival hiscence-Type defects On The long-Term Stability Of peri-implant rates of implants placed in maxillary sinus grafted with bovine hydroxyapatite Health. a prospective randomized Controlled Clinical Study. (Bio-Oss®Geistlich) and resorbable collagen membranes (Bio-Gide®Geistlich) in patients with residual bone height of up to 5 mm, residual bone width of at least 5 Narja Sahm (Germany), Vladimir Golubovic, Frank Schwarz, Jürgen Becker mm and with maintenance of an acceptable vertical intermaxillary relationship. Methods: Sixty patients (age 26-70 years) participated in this study. Eight pa- Objectives: The present clinical study aimed at investigating the impact of re- tients required bilateral sinus grafts and 52 patients required monolateral si- sidual defect height (RDH) following guided bone regeneration (GBR) in de- nus grafts (total 68 sinuses). Residual bone volumes were measured in the hiscence-type defects on the long-term stability of peri-implant health over a preoperative computer tomography (CT) for each patient; the average bone period of 4 years. height was 4.49 mm and the average bone width was 5.84 mm. Methods: In a total of n=23 patients, RDH values in dehiscence-type defects All patients were treated with the same surgical technique consisting of sinus at titanium implants were clinically assessed after 4 months of submerged floor augmentation with a lateral approach. Bovine hydroxyapatite was the sole44
    • clinical reSearch, clinical StudieSgraft material and a resorbable membrane was placed over the lateral window. symptoms. In one patient with a light sinusitis post-op, treatment with antibi-All implants were placed in a delayed procedure. 120 implants (58 Straumann otics resolved symptoms. After 6 weeks all patients showed adequate woundimplants, Straumann®, Basel, Switzerland; 62 Astra, Astra Tech®, Mölndal, healing. The average operating time was 10 minutes.Sweden) were scheduled for subsequent surgery 6 months after the graft was Conclusions: This study shows the possibility of treating patients with an oro-performed. Prosthetic load was performed after 5 months from implant place- antral communication directly after extraction using a biodegradable mem-ment. brane without primary surgical closure of the wound. More research is neededresults: All sinus grafts showed full engraftment. The most frequent intraop- to confirm the results and the indications of the new method.erative complication was perforation of the sinus membrane (18%), but nonewas such to compromise the completion of the surgical reconstruction. Per-forations were treated either by increasing the elevation of the sinus mucosa, 230 i Five years Clinical Follow upand/or with the aid of resorbable collagen membranes. The mean follow-up Bone regeneration With Cap Bioceramicsfrom prosthetic loading was 24 months. The marginal bone loss around dentalimplants was 0.85 mm (ds +/- 0.35 mm); only three implants showed a higher Guy daculsi (France), Clemencia Rodriguez, Sylvia Mitjamarginal bone loss, which was considered as clinical failure (Albrektson crite-ria). No implants were removed during the follow-up period. The overall sur- Objectives: Among all the materials used for pre-implant bone reconstruc-vival and success rates of implants were 100% and 97.5% respectively. tion, autologous bone is the gold-standard. A second site surgery is, however,Conclusions: Despite the limited follow-up, the present study suggested that required, making the surgery more complicated. To overcome the autograftbovine hydroxyapatite, used alone for maxillary sinus grafting, is a reliable and limits, many biomaterials were proposed. Human or animal origin materialspredictable material for the survival and the success of dental implants placed have disadvantages: limited supply and risk of contamination. Consequently,in patients with residual bone height of up to 5 mm, residual bone width of at synthetic products were developed, like MicroMacroporous Biphasic Calciumleast 5 mm and entailing maintenance of an acceptable vertical intermaxillary Phosphate (MBCP), a mix of hydroxyapatite (HA) and ß-tricalcium phosphaterelationship. (ß-TCP). MBCP offers a great potential for bone regeneration as its chemi- cal composition is close to biological bone apatites. MBCP already proved its efficiency in different human clinical applications, but there was only a little228 i Comparative volumetric and density study of symphysis clinical data on maxillofacial surgery.donor defects: Filled or unfilled with bone substitute The aim was to report 5 years of clinical follow-up on bone regeneration after socket preservation using MBCP with 2 HA/TCP ratios, for evaluation of re-devorah Schwartz-arad (israel), Pablo Altuna Fistolera, Albert Calaf Cot sorption and bone ingrowth at the expense of the bioceramic. Methods: MBCP® (ratio 60/40) and MBCP+®(ratio 20/80) were used. MBCP®Objectives: Intra-oral autogenous bone grafts are a convenient source of bone in and MBCP+® are biphasic CaP intimate mixture of HA/TCP 60/40 and 20/80,reconstruction of the residual ridge prior to dental implant placement. The aim with interconnected macroporosity and microporosity (70% total porosity withof this study is to evaluate bone volume and density of symphysis donor defects 75% of macropores of 300 to 600µm and 25% of micropores).filled with bovine bone material compared with unfilled symphysis donor defects. Forty cases have been distributed in three groups for alveolar pocket filling.Methods: The study included 24 patients who underwent either alveolar ridge Seven cases without filling are controls, as the two others are filled with MBCPreconstruction or maxillary sinus elevation. Two groups were studied: symphy- 60/40 or MBCP 20/80. X-Ray at 0, 3, 6, 12 months and a 5 years follow-up forseal donor defects filled with bovine bone material, and unfilled symphyseal some patients were performed. Bone biopsies were realized before dental im-donor defects. Pre- and post-operative volumetric and bone density variables plantations. Light microscopy, SEM and µCT were performed.were determined using CT scans and the software program SimPlant®. results: In all the 40 cases, radio-opacity of the implantation site decreasesresults: At 6 months post-operative, the filled donor defects exhibited a sig- over time, indicating resorption and bone ingrowths at the expense of the twonificant increase in bone volume and density (97.7% and 116%, respectively) bioceramics. No difference in the resorption kinetics appeared on X-Ray. Aftercompared with unfilled donor defects (73.4% and 35.5%, respectively). At 18 1 year, the implantation site looks like the physiological bone and is maintainedmonths post-operative, volume and density of unfilled donor defects were re- iover time. The newly formed bone is preserved after 5 years, unlike the controlevaluated, yet no significant increase was found in bone volume. cases (without filling), where we observed a decrease of 2 to 5 mm.Conclusions: Unfilled donor sites generate defects that cannot achieve a "res- In light microscopy, bone ingrowth is observed in all the biopsies. Bone tra-titutio ad integrum", while filled donor sites associate with complete bone beculae appeared in the samples, without statistical differences and a largeregeneration as determined by bone volume and density analysis. High bone osteoconduction is noticed in close contact to the granules. More resorptiondensity of filled donor defects may indicate high bone quality and could enable over time is measured for MBCP 20/80, when time of implantation and residualre-entering of the site. granules are compared. Conclusions: The immediate filling of the alveolar socket after tooth extrac- tion is a preventive method to bone resorption. In the long term, resorption229 i a New Method Of Closing an Oroantral Communication and bone growth were demonstrated for both MBCP® with two HA/TCP ratiosusing a resorbable Membrane (40%/60% and 20% 80%). This data confirms the resorbability of MBCP® and the high osteoconduction and regeneration.Joris Wes (Netherlands), MF Wes, BJ Wes, JPR van MerkesteynObjectives: An oroantral communication (OAC) after extraction of maxillary 231 i injectable Bone Substitute (MBCp Gel®):posterior teeth is treated in most cases by primary surgical closure. This study Clinical results in Human Maxillo-Facial Surgerypresents a new, simple and time-reducing method using a Geistlich Bio-Gidemembrane® without primary closure. Guy daculsi (France), Pierre Weiss, Léon Philippe Clergeau, Bénédicte Henckel,Methods: Twelve patients with an OAC after extraction of a maxillary molar Bernard Giumelliwere treated according to the new method. First the alveolus is inspected afterextraction and loose fragments are removed. A Geistlich Bio-Gide membrane® Objectives: Calcium phosphate bioceramics, which are often used for boneis rolled in a cone-shaped manner. Then the tip of the membrane is folded regeneration because of their close resemblance to the bone mineral phase,over and placed in the alveolus. The membrane is convex towards the maxillary display biocompatibility, bioactivity and excellent osteoconductive properties.sinus and concave towards the oral cavity. When the nose-blowing test is nega- In odontology, the size and accessibility of the various sites (endodontic, ex-tive, a cross mattress suture is placed for fixation of the membrane. Peripac® traction?) required the development of injectable forms. These new therapeu-was used in most patients as an intra-oral bandage. Patients had check-ups tic approaches and improvements in bioceramics mixed with hydrogel have ledtwo and six weeks postoperatively. to the development of injectable bone grafts for bone regeneration.results: After two weeks all OAC’s were closed. In one patient with pre-op Methods: MBCP® Gel is a CaP aqueous suspension obtained by associatingsinusitis symptoms, treatment with rinsing the sinus and antibiotics resolved BCP ceramic (60% HA and 40% beta-tricalcium phosphate; MBCP®, mineral 45
    • phase granules 80 to 200 µm in diameter) with a 3% aqueous solution of hy- Conclusions: The results of the present long-term follow-up study correlated drogel. A clinical trial (Nantes Hospital) was performed in 11 human sockets with results found in literature. According to those, with appropriate indica- after extraction (36 or 46). We have checked the clinical reaction by question- tions, angled implants can be a successful therapeutic method in severely re- ing patients about pain. Radiography was performed before implantation, 15 sorbed maxillary bone, and as such, they could be an alternative to extensive days, 3 and 6 month afterwards. For some patients we have radiography after bone augmentation procedures. 3 years and some biopsies to control bioactivity have been performed as part of the clinical trial. Scanning Electron Microscopy SEM Micro Computerized Tomography and light 234 i The influence Of periodontal Treatment microscopy were performed. On Serum lipid and Systemic Marker levels in patients results: See photos and analysis. It was an explorative study and the results With destructive periodontal disease showed no pain due to the biomaterial implantation, no infection, no inflamma- tion and perfect biocompatibility. The safety and the bioactivity of this concept Wisam kamil (Malaysia), Rola Habashnah, Lina Abbood of biomaterial were confirmed in human implantation, after several animal pre-clinical studies. Objectives: Data on whether periodontal therapy affects serum lipid levels Conclusions: Human clinical trial with MBCP Gel® confirm the biocompatibil- is inconclusive. The purpose of this study is to investigate the effect of non- ity in human, but the kinetics of resorption and bone substitution seem to be surgical periodontal therapy on the cholesterol levels and hs-CRP of medically different from the animal studies. The radiological study shows no osteolysis healthy individuals suffering from advanced periodontitis. in contact of the biomaterial, an increase of the density and a decrease of the Methods: Following protocol review and approval by the Institutional Re- volume of the injected biomaterial. view Board of Jordan University of Science and Technology a total of fifty five periodontitis patients randomly distributed into either a treatment group (37 patients) who received non-surgical periodontal therapy with intensive oral 232 i Comparative review Of Sinus augmentation Techniques hygiene instructions and a repeated course of therapy for residual bleeding in periodontal pockets or a control group (18 patients) who received delayed Orsolya rásonyi-kovács (Hungary), Árpád Joób-Fancsaly periodontal treatment after completion of the clinical trial evaluation. Medical history, demographic data and clinical periodontal parameters, total choles- Objectives: Vertical resorption of the alveolar process and pneumatisation of the terol, LDL, HDL, triglyceride, and C-reactive protein were collected at baseline maxillary sinus lead to a reduced distance between the sinus and the alveolar and three months at reassessment appointments. process. Sinus augmentation surgery is widely used to augment the upper molar results: The results showed statistically significant improvements for all peri- region before implant placement. Tatum described the open technique in 1986 odontal clinical parameters and the non-surgical periodontal therapy had no and it has been developed further by several innovations since that time. Sum- effect on the lipid parameters (P-Value=0.322, 0.540, 0.451, and 0.154 for LDL, mers reported the closed technique in 1994. It is less traumatic, but allows a HDL, Total Cholesterol, and Triglycerides respectively) in contrast to the signifi- limited extent of augmentation. The aim of the present poster is to compare the cant decrease in the inflammatory marker CRP (P-Value=0.003). advantages and disadvantages of the various sinus augmentation techniques via Conclusions: In this study population, serum lipid levels were not associated literature review, and to present the success rates we found in our cases. with any improvement in periodontal heath while the destructive periodontal Methods: The success rates of various sinus lift techniques were examined disease associated with increased circulating concentrations of his-CRP and clinically and radiologically in accordance with internationally accepted criteria the periodontal therapy reduces CRP levels. in patients treated during the past ten years in our clinic. results: The present study proved that the most successful technique is open sinus augmentation, and that the other techniques and innovations (closed, 235 i Guided Bone regeneration in Sinus lift procedures balloon etc.) have fewer indications, but can be successful when they are used properly. Sinus grafting /sinus elevation/ is trustworthy, has good results and ramón Gómez Meda (Spain), Maria Varela Cruz, M. Isabel Prada Lopez, Sonia is an effective method for sinus augmentation. The success rate of augmenta- Liste Grela tion cases in the present study was 97.2%, comparable to results published in international literature. Objectives: The aim of this study is to establish the efficiency of the sinus lift Conclusions: The present poster reviewed and compared various techniques procedure with a lateral window approach in the implant-supported rehabilita- via a retrospective study and literature review. An attempt is made at providing tion of very atrophic edentulous posterior maxillae (no more than 1-4 mm of a guideline to the indications and usage of the various techniques. alveolar bone height). Methods: This study retrospectively evaluated the results of 39 sinus lift graft augmentations performed to place 75 implants in the posterior maxilla. Grafts 233 i angled implants as an alternative To were accomplished with Bio-Oss® combined with autogenous bone removed Bone augmentation in Severely resorbed Maxilla from within the mouth. The donor site was the external wall of the sinus and the zygomatic arch. A safescraper was used. Therefore no second location site Tamás ruszin (Hungary), Béla Czinkóczky, Sándor Bogdán was used. Sand-blasted screw-type implants (Xive® implants, by Dentsply) were placed simultaneously to the surgery. A membrane (Bio-Gide®) was used to cov- Objectives: The possibilities of implant restoration in the severely resorbed er the graft in all cases. Implants were exposed 3 to 6 months later. After waiting maxilla (Fallschüssel class 5) were reviewed. These include implant placement one month for the soft tissue to heal, the implants were prosthetically restored. in combination with bone augmentation, angled implants, or "zygoma implants. The osseointegration was evaluated during a follow-up period of 6 to 36 months. Furthermore, the purpose of the study was to do a long-term follow-up of bone Implant survival rate and peri-implant conditions, such as marginal bone re- loss around angled implants in the severely resorbed edentulous or partially sorption (mm.), pocket depth (mm.), plaque and bleeding indices were evaluated. dentate maxilla. results: The most frequent intraoperative complication of the technique was Methods: During eight years (average 4.3 years) of follow-up, 24 patients with 28 tearing of the sinus membrane in 6 cases (15%). There were no clinical com- angled implants were examined, where the implant angulation was more than plaints of maxillary sinusitis. Ten core biopsy specimens were taken at the time 15 degrees (the smallest angulation was 34 degrees and the highest 56 degrees). of the second surgery and evaluated. Histological evaluation of cores revealed In every case the implant length was minimum 13 mm. All implant supported good bone formation around the Bio-Oss particles after 6 months. restorations were screwed or cemented bridge works. All patients were recalled The use of long implants provided for a favourable implant-crown ratio (›1.09) and every six months; the implants were examined clinically and radiologically. produced an overall clinical survival rate of 100% over the observation period. results: Out of 28 implants one had to be removed in the 5th month, around Conclusions: On the basis of this retrospective study, we conclude that excel- one implant a 2.5 mm bone loss was found during the 1st year after implant lent osseointegration and peri-implant parameters may be anticipated for im- loading. Around the rest of the implants no significant bone loss was noted plant-supported restorations placed after sinus lift procedures in combination after the initial bone loss. with Bio-Oss and Bio-Gide.46
    • clinical reSearch, clinical StudieS236 i Computed Tomography analysis Of Schneiderian eosin and Massons trichrome, were used. 300 biopsies were processed for his-Membrane after lateral Sinus augmentation procedure tomorphometric evaluation of the mean percentage of bone, residual graft and connective tissue by area. A total of 746 implants were placed into grafted sites.Guillaume anduze-acher (France), Benoit Brochery, Philippe Bouchard results: All patients had uneventful postoperative healing. Adequate bone vol- ume was clinically observed in all cases. All implants were restored functional-Objectives: Bone substitute grafting is nowadays a well-established proce- ly. Histological analysis revealed the presence of newly formed bone in all biop-dure for maxillary sinus floor augmentation before implant placement. So sies. Bone showed a lamellar well-organized structure, in direct contact withfar, the impact of these procedures on the sinus membrane has not been residual graft (RG) particles. There was no evidence of acute inflammatory in-explored. Therefore, it is of interest to evaluate the modifications of the Sch- filtrate. Histomorphometric evaluation revealed an overall mean bone volumeneiderian membrane following grafting procedures. (MBV) of 51.6±17.1%, 32.7±13.5% of connective tissue (CT), and 15.7±10.3% ofThe aim of this study was to measure, with computed tomography, changes RG. The MBV was higher in cases where a combination of AB + DFDBA wasto the Schneiderian membrane following lateral sinus augmentation pro- used (54.2%) (p‹0.05). The addition of PRP in AB did not significantly increasecedure with a bovine bone xenograft (Bio-Oss®) and a collagen resorbable MBV (p›0.05). In detail, analysis of the samples showed an average of: a) 1stmembrane (Bio-Gide®). group: 51.6% MBV, 19.1% RG particles, and 29.3% CT, b) 2nd group: 54.2% MBV,Methods: Thirty lateral sinus augmentation procedures were performed on 17.6% RG particles, and 28.2% CT, c) 3rd group: 51.9% MBV, 12.7% RG particles,26 healthy patients (22 females) with a mean age of 51.2 +/- 8.33 years. Bo- and 35.4% CT, d) Control group: 48.6% MBV, 13.3% RG particles, and 38.1% CT.vine xenograft (Bio Oss®) was used as bone substitute and the lateral win- Conclusions: The use of DFDBA + AB 50/50 mixture appears to promote, in thedow was closed with a resorbable membrane (Bio-Gide®). Post operative severe atrophic maxilla, a satisfactory bone formation. DFDBA is biocompat-computed tomographies (CT scan) were analyzed with an image analysis ible and osteoconductive when used in SFA procedures and it may be usedsystem (ImageJ®). The thickness of the sinus membrane, the alveolar bone safely without interfering with the normal reparative bone process. The ad-height, and the sinus filling were measured pre and postoperatively. Sta- dition of PRP did not appear to significantly enhance bone formation. No in-tistical analysis (p=0.05) and intra-class correlation were performed. Cor- vestigated biomaterial was completely resorbed, but all the residual particlesrelation between the Schneiderian membrane height pre and post opera- demonstrated close bone integration to form a hybrid tissue.tion were defined by linear regression. Finally, robust multiple regressionanalysis tested the association between dependant variable (Schneiderianmembrane height) and independent variables (tobacco, periodontal ante- 238 i Guided Bone regeneration For Extraction Socket augmentation:cedents, time between CT scans, complications, bone substitute, aggressive Clinical, Histologic and Histomorphometric Study in Humansor chronic periodontitis).results: Ten months post operation (+/-5.64 months), a significant decrease ioannis Gisakis (Greece), Demos Kalyvas, Konstantinos Tosios, Vasilios Petsinis,of the mean sinus membrane thickness was observed (p=0.017), from 2.28 Konstantinos Alexandridis(+/- 2.14) mm to 2.07 (+/- 1.88) mm. Non-significant resorption of crestalcrest was found (p=0.64), from 3.69 (+/- 1.19) mm to 3.63 (+/- 1.22) mm. Objectives: The preservation of bone volume immediately after tooth removalThe bone fill into the sinus was 13.19 +/- 3.11 mm, with an available total might be necessary to optimize the success of implant placement in termsbone height of 16.94 +/- 3.33 mm. The correlation between pre and post of aesthetics and function. The objectives of this 3-months randomized, con-membrane thickness was low (r=0.15). Multivariate analysis highlighted the trolled, clinical study were: 1) to compare the bone dimensional changes fol-influence of post operative healing time and chronic periodontitis (p=0.05). lowing tooth extraction alone versus extraction plus ridge preservation usingConclusions: The Schneiderian membrane may be subjected to modification allograft or xenograft and a collagen membrane; and 2) to analyze and com-following sinus augmentation procedures. This modification may be inter- pare histological and histomorphometric aspects of the extraction-alone sitespreted as an adaptation of the membrane over time. In healthy sinuses, the to the grafted sites.preoperative thickness of the membrane is not a prognosis factor for the Methods: 24 adult patients (19 male, 5 female, mean age 36.3 yrs) requiring anpostoperative thickness of the membrane following lateral augmentation. extraction and delayed implant placement were randomly selected to receive either extraction alone (EXT, control group, 8 cases) or ridge preservation (RP) using: demineralised freeze-dried bone allograft (DFDBA, 8 cases) or deprot-237 i Maxillary Sinus Floor augmentation For implant placement: einized bovine bone mineral (BBM, 8 cases) and a collagen membrane. 12 ex-Clinical, Histological and Histomorphometric Study in 150 patients traction sites were located in maxilla and 12 in mandible. 8 sites (33.3%) were located in anterior areas, 7 in premolar regions (29.2%) and 9 in molar areasdimitrios zabaras (Greece), Ioannis Gisakis, Spyros Bouboulis, Athanasios (37.5%). Following extraction and at the time of implant placement (IP), hori-Spanos, Vasilios Petsinis zontal and vertical ridge dimensions were measured. After a healing period of 3 months, bone core biopsies were collected, by a trephine bur, at IP. Five-micronObjectives: The reconstruction of edentulous patients with adequate bone vol- thick sections, stained with haematoxylin-eosin and Massons trichrome, wereume by using dental implants has become a viable treatment option with high used. A total of 24 biopsies were processed for histomorphometric evaluationpredictability. However, initial stabilization is difficult to achieve in the poste- of the mean percentage of bone, residual graft and connective tissue by area.rior maxillary regions where cortical bone is thin or absent due to severely results: The width of the RP group decreased from 9.2±1.2 mm to 8.0±1.4 mmresorbed alveolar ridges. Maxillary sinus lift procedures applied with various (p›0.05), while the width of the EXT group decreased from 9.1±1.0 mm to 6.4±2.2grafting materials enable clinicians to place implant-supported prostheses mm (p‹0.05). The vertical change at the buccal side for the RP group was a gaineven in cases with increased pneumatization of the maxillary sinus. The ob- of 1.3±2.0 mm versus a loss of 0.9±1.6 mm for the EXT group (p‹0.05). Thejective of this study was to histologically and histomorphometrically evaluate biopsies harvested from the grafted sites revealed formation and remodellingnew bone formation after maxillary sinus floor augmentation (SFA) using au- of trabecular bone, which was highly mineralized and well structured. Newtologous bone (AB), demineralised freeze-dried bone allograft (DFDBA) and bone formation and connective tissues (CT) on and around DFDBA and BBMplatelet-rich plasma (PRP). particles were widespread. No inflammation was observed. Histomorphomet-Methods: 150 patients (80 women, 70 men, mean age 62 yrs) with bony height ric analysis revealed more bone in the EXT group, 70.1% versus 68.2% in theunder the sinus ‹3 mm, in need of bilateral SFA using lateral window approach, RP group (p›0.05).The RP group included both vital bone (58.9%) and non-vitalbefore implant placement, were recruited. A 2-stage protocol was conducted. (9.3%) graft fragments. In detail, analysis of the samples showed an averagePatients were randomly divided in 3 groups of 50 patients each. In each group of: a) DFDBA group: 58.7% vital bone (VB), 5.9% residual graft particles (RGP),the right sinus was grafted with AB (in total 150 sinuses, control group, CG), and 35.4% CT, b) BBM group: 59.1% VB, 12.6% RGP, and 28.3% CT, c) Controlwhile the left sinus (experimental group, EG) was treated with: 1st group: DFD- group: 70.1% VB and 29.9% CT.BA, 2nd group: DFDBA+AB, in the ratio 50/50, 3rd group: AB+PRP. In all cases Conclusions: Ridge preservation using DFDBA or BBM and a collagen mem-lateral osteotomies were closed with resorbable collagen membranes. After a brane improved ridge height and width dimensions when compared to extrac-healing period of 6 months, bone cores biopsies were collected, by trephine bur, tion alone. The quantity of bone observed on histological analysis was slightlyat implant placement. Five-micron thick sections, stained with haematoxylin- lower in preservation sites, although these sites included both vital and non-vi- 47
    • tal bone. Overall, no serious complication was seen during the healing period. Objectives: In implant placement post extraction we are faced with different In most patients marginal mucosa and bone levels remained stable following challenges; a major challenge is to gain the primary stability of the inserted restoration. Implant success and survival rates were 100%. implants. The most important challenge is the coronal gap between the im- plant and surrounding bone with exposed implant threads. We are faced with both vertical and horizontal bone defects besides fenestration in some cases. 239 i lingual Foramina and Their Bony Canals Different augmentation material and techniques can be utilized to solve this in The Median region Of The Mandible: a CBCT Study challenge. One of the most important criteria of augmentation material selec- tion is its osteoconductive properties, providing good volume stability and ex- iuliana Babiuc (romania), Mihaela Pauna ceptional handling properties. Straumann® Bone Ceramic fully synthetic bone substitute with optimized morphology leads the way to new vital bone, with Objectives: To investigate the presence of the lingual foramina and their bony excellent wetting properties and good handling. canals in the midline of the mandible by means of cone beam computed to- Purpose of this prospective study was to evaluate the possibility of augmenting mography and to describe their anatomical features. the exposed implant threads with Straumann® Bone Ceramic. Methods: 36 subjects underwent CBCT examination of the mandible for im- Methods: 12 patients indicated for extraction and immediate placement in the plant therapy. The sagittal and axial cross sections through the anterior man- anterior and premolar area and removal of the defective tooth. Curettage of dible were carefully examined in order to detect the lingual vascular canals. the socket and removal of all granulation tissue. Insertion of the selected im- Their presence, number, position, diameter and trajectory were established. plant according to the manufacturer’s protocol. 7 sites with marginal defects, results: Lingual foramina in the midline of the mandible were observed in all 5 sites have fenestration defects with exposed threads (4~12 showed implants 36 subjects. An average of 1.5 foramina/subject was identified. In 31% of the threads). All the exposed threads in both marginal and fenestration defects cases more than one foramen and canal could be observed. The average diam- were registered clinically and photographically before augmentation. All cases eter of the canals was 0.84 mm. The average distance from the foramina to the received a first layer of thin autogenous bone harvested by bone scrapers. All base of the mandible was of 11.2 mm. 62.0% of the canals had a descending sites augmented with Straumann® Bone Ceramic. trajectory, 17.3% were solely anterior and 20.7% had an ascending trajectory. All cases were covered with collagen membrane. After 6 months in secondary Conclusions: CBCT examination can reveal multiple anatomic features of the surgery both marginal and fenestration defects were evaluated by measur- mandible that must be taken into account when planning an implant treatment. ing the exposed implant threads registered clinically and photographically. All It can demonstrate the presence, position, size and morphology of the lingual cases received definitive restoration after 6 months. All cases were evaluated vascular canals in the median region of the mandible. Clinicians should be radiographically for 18 months. aware of these anatomical structures and their possible implications. results: In this prospective clinical study 12 patients (7 females, 5 males) were selected with special inclusion criteria indicating single tooth extraction and immediate placement in the anterior and premolar regions. All patients re- 240 i Clinical Evaluation Of a Novel Bone Graft Material ceived root form implants with length (13 mm ~16 mm), diameter (3.5 mm ~ 4.4 as a Composite in Sinus lifting applications: a pilot Study mm). In this prospective study 7 implant sites have marginal defects and 5 sites have fenestration with exposed implants threads (4 ~ 12) was recorded. After 6 alper Gultekin (Turkey), Safak Ahmet, Z.Cuneyt Karabuda months of augmentation with Straumann® Bone Ceramic, we gained complete coverage of exposed implant threads, which was seen in 11 of 12 implant sites. Objectives: Insufficient bone volume is a common problem in the rehabilitation Complete coverage of 5 sites with fenestration defects. Complete coverage of of the edentulous maxilla with an implant supported prosthesis. In the posteri- 6 of the 7 sites with marginal defects. 1 site showed 1 to 2 remaining exposed or maxilla, the presence of the maxillary sinuses often limits the available bone implant threads of the marginal defect sites. Radiographic evaluation extended height for dental implant placement. Maxillary sinus floor augmentation has to 18 months showed stability of marginal bone around implants. been shown to be a predictable approach to correct this deficiency. Since the Conclusions: In implant placement post extraction, different augmentation technique of sinus elevation was introduced, various bone replacement materi- materials and techniques can be utilized to overcome the vertical and hori- als have been used successfully. Biphasic calcium sulphate (BondBone, MIS- zontal bone defects. In this prospective study Straumann® Bone Ceramic fully Israel) is a synthetic osteoconductive, bioresorbable novel bone grafting mate- synthetic bone with optimized morphology can be used to obtain marginal bone rial that has been recently introduced for clinical use in sinus lift procedures. with excellent wetting properties and good handling. Straumann® Bone Ceramic Methods: This study is the first to use dental volumetric tomography (DVT) to can be used successfully to augment exposed implants threads. histologically and radiographically evaluate and compare two different graft ma- terials; inorganic bovine bone matrix (ABBM) BioOss (Geistlich, Switzerland) and HA/ß-TCP – 4Bone (MIS, Israel) mixed with biphasic calcium sulphate (BCS) as 242 i The use Of Frozen Homologous Bone in patients a composite. A total of 11 patients with insufficient bone height in the maxillary affected By Serious upper Maxillary atrophy posterior area were selected. Following the sinus lifting procedure with a lateral approach, one composite graft material (ABBM + BCS) was placed in one side paolo piacentini (italy), Gianmaria Agnelli, Massimo Bellia, Umberto Zanetti and the other composite (HA/ß-TCP + BCS) was placed in the other side. Five months after, a trephine core was taken for bone biopsy core samples and sent Objectives: The authors present a series of 12 patients affected by serious up- for histological analysis. Also DVT were taken three times as before the sinus per maxillary atrophy (degree 5–6 according to Cawood and Howell) in which lift operation, right after the procedure and lastly five months after healing for fixed implant rehabilitation, after grafting frozen homologous bone, has been radiographic evaluation of available bone volume during the healing phase. realized, with follow up at 48 months. results: No complications were observed during the surgical procedures. No The aim of the study is to demonstrate that the use of frozen homologous bone signs or symptoms of maxillary sinus disease were observed during the five can be an alternative to the autogenous bone in the rehabilitation of serious months after sinus lift procedure. High resorption rate in early healing phase maxillary atrophies, guaranteeing the same clinical results in terms of stabil- in DVT measurements were measured for both composite graft materials. New ity of tissues and integration of positioned implants. In this work, an analysis bone formation was also detected in histological samples. was made of the histological implication of frozen homologous bone integrated Conclusions: Future studies are needed to confirm the ability of this novel bone on the native bone. The histological aspects were compared with the normal replacement material with different mixture ratios as a composite and for lon- evolution of bone guarizon. So 12 pz was examined. At time points T0, T1, T2. ger healing periods. Methods: 12 patients with serious maxillary atrophy were included in the study. They underwent the usual surgical procedure: inlay and onlay reconstruction using frozen bank bone in association with PRP. After 6 months means of syn- 241 i Evaluation Of Straumann® Bone Ceramic in The Treatment thesis, they were then removed and contemporary implants were inserted fol- Of Exposed implants Threads, prospective Clinical Study lowing the usual technique. In 4 patients, as adequate stability was achieved, we were able to proceed with an immediate load; while in other cases, in which atef ismail (Egypt) an adequate torque insertion was not achieved, a differed implant load was48
    • clinical reSearch, clinical StudieSpreferred (8 patients). After 4–5 months the surgical sites were re-opened and enous grafts have been used as the material of choice; in recent years allo-we proceeded with implant rehabilitation using either a provisional screwed plastic materials have gained popularity because of their availability and easeimplant, or a definitive screwed implant (in the immediate load cases). of use. Lyodura was a standard for the reconstruction of the orbital floor untilresults: The evaluation consisted in a histological control at T0, T1 (implant cases of Creutzfeldt-Jakob disease were reported, so that polydioxanone (PDS)insertion) and T2 (follow up or during secondary intervention. A good integra- is widely used today. However, infections around the implant are reported.tion of the frozen homologous bone with the native bone was achieved. Subse- Methods: This report presents the results obtained by the application of col-quently 76 superior maxillary implants (diameter 4 and 13-11.5 mm of length lagen membrane (Bio-Gide) which was treated surgically because of blow-outrespectively) were evaluated: the loss of 2 implants out of 76 (2.63%) with a fractures from 2008 and 2010 at the Department of Maxillo-Facial Surgery ofsuccess rate of 97.5 was demonstrated. the Istituto Ortopedico I. Galatioto Villa Salus Augusta (SR).Conclusions: The rehabilitation of serious maxillary atrophies using fresh ho- In this clinical study on 14 patients with orbital floor defects, we evaluated themologous bone seems to be a viable alternative to the autogenous bone treat- use of a collagen membrane (Bio-Gide). Computed tomography controls andment technique. The histological aspect of T1 bone shows that there was less ophthalmologic examinations were performed after 6 months.osteoblast and osteocitis than in normal bone. This characteristic seems to results: No intra-operative complications occurred. Peri-operatively and post-correlate with a correct cortical relationship and engaged midollare that con- operatively, no complications such as infections were observed.firms a different pattern of integration with bony material of the host. In instances of orbital rim fractures, the collagen membrane could additionally cover these defects. After 6 months, computed tomography controls revealed a complete reposition of orbital tissue and, very important, even bone regenera-243 i Fares Wedge Technique: tion. Diplopia and hypoaesthesia were completely reversed after half a year.a New Simple Method For 3d ridge augmentation Smaller defects (up to 1 cm) of the orbital floor can be restored with a collagen membrane. However, for larger defects, stability may not be sufficient.Fares kablan (israel) Conclusions: There was a reduction in operative time with the use of Bio-Gide membrane implants compared with the use of bone, no infections occurred soObjectives: Recently, there has been an increase in the number of patients Bio-Gide collagen membrane is a safe and very useful material for orbital floorwith different degrees of atrophic jaw ridges who contact oral surgeons to seek fracture reconstructions.rehabilitation with dental implants. Many of them have had removable appli-ances, so the need for bone augmentation is increasing. Several bone graft-ing techniques and materials are used, but consistent results are difficult to 245 i analgesic Consumption Following Sinus lifting Surgeryachieve especially in the case of mandible and vertical defects.Space maintenance capacity of the graft materials used is an important fac- Shirali Shiraliyev (Turkey), Volkan Arisan, Alper Gultekin, Cuneyt Karabudator among several factors affecting success of bone augmentation procedures.In this report I present a new and simple method “Fares Wedge technique" for Objectives: The aim of this study was to investigate the rate of analgesic con-3-dimensional ridge bone augmentation. sumption following open sinus lifting surgery.Methods:41 patients (58 sites), 11 at maxilla, 47 at mandible were treated by Methods: The study group consisted of 26 patients consisting of 10 male and 16this technique during the last years(Sept 2008- Dec 2010). Retromolar/Ramus females who applied to the Istanbul University Faculty of Dentistry, Departmentare the gold standard as donor sites. In one case we used the palatal torus and of Oral Implantology for treatment for maxillary edentulism. Due to insufficientin another case bone block from the osteotomy site of maxillary correction in vertical bone height in the posterior maxilla, sinus lifting surgery was performedthe same operation. After preparation of the graft block and recipient site, our using the lateral window technique. The elevated sinus space was filled with in-technique used slices of the former (creating thin bone wedges) and grooves organic bovine bone matrix (Bio-oss/Geistlich, Switzerland) and closed by a re-of the latter. We created multiple compartments which were filled with allog- sorbable collagen membrane (Bio-Gide/Geistlich, Switzerland). The number ofenous bone, and covered with biodegradable membrane, suturing the flap ten- analgesic+ anti-inflammatory naproxen sodium tablets (550 mg, Apranax forte/sion free. In some cases we used soft tissue free graft. We waited 3–4 months Abdi Ibrahim, Turkey) consumed in the postoperative week was recorded by alluntil implants were inserted. During this period we recalled the patients sev- patients. Results were analyzed using the Mann Whitney U test (p‹0.05).eral times to observe the healing process. results: Mean age of the patient group was 55.4 (SD 7.75) years. All surgicalresults: The recovery time, morbidity, costs and complications were all favour- operations were completed without any complications. The mean total num-able in all of our patients. The success rate was 97%, in two patients the graft was ber of consumed analgesics was 6.12 (SD 1.89) tablets throughout the weekpartially exposed and treated with saving and rounding the exposed wedges and after surgery. Mean number of analgesics consumed by men (6.1 (SD 1.24) andoral hygiene maintenance, but the augmentations were saved. In one additional women (6.22 (SD 1.13) was statistically not significant (p=0.12).case, we lost the majority of the graft volume. At 40 sites implant insertion was Conclusions: Within the limits of this study it can be concluded that sinus lift-successful (115 implants), at 2 sites the follow up failed and 15 sites are still in the ing surgery using the lateral window technique involving deproteinized bovinerecall period, and have favourable healing. The bone gain was 3–8 mm vertically bone and a resorbable collagen membrane leads to a moderate level of anal-and 4–10 mm horizontally. No complications were observed at the donor site. gesic consumption (6.12 tablets) in the following week.Conclusions: Wedge technique utilizes Auto/Allogenous bone grafts. The goalof autogenous graft slices was space maintenance, and that of the allogenousmaterial was to fill the compartments produced between the autogenous bone 246 i a New Surgical Technique Of Sinus Floor Elevationwedges. The donor site is appropriate with favourable morbidity and costs. Thebone volume achieved was satisfactory, especially since the majority of our Tatiana kolesnikova (russia), Ziad Raadaugmented areas had 3-dimensional posterior mandibular defects. The bonevolume with lateral augmentations was more satisfactory. Objectives: Grafting of the maxillary sinus in both one- and two-stage proto- cols has become a highly predictable surgical technique for site development and for the placement of implants to support dentures. All of the surgical tech-244 i reconstruction Of Orbital Floor Fractures niques to elevate the maxillary sinus present the possibility of perforating theWith Collagen Membrane (Bio-Gide) Schneiderian membrane. Thus, complications can occur during the osteotomy, which is performed with burs, or during the elevation of the membrane usingMassimo Marasco (italy) manual elevators. The purpose is to present a new surgical technique that radically simplifiesObjectives: Orbital floor fractures, often combined with zygomatic fractures, maxillary sinus surgery, thus avoiding perforating the membrane.are common fractures of the midface. Surgery of orbital fractures is done to Methods: The method includes “transposition of the maxillary sinus floor byfree incarcerated or prolapsed orbital tissue and to restore the anatomical interlaminar osteotomy of the alveolar ridges”. The aim of the method is toskeletal size of the orbit and to prevent soft tissues fibrosis. Different materials enhance the osseointegration of the implant by forming a subantral space forhave been tested over the years to achieve this purpose. Traditionally, autog- placement of the implant. The risk of damaging the mucous membranes of 49
    • the maxillary sinus in this case is lower because all the walls are made of 248 i Treatment Of Miller Class i and ii Multiple Gingival recessions bone tissue. A very important condition should be considered when applying With a Bioresorbable Collagen Matrix (Mucograft®): a prospective, this method and it is the height of the subantral alveolar ridge, which should randomized, Controlled Split-Mouth Clinical Trial not be less than 5 mm. The core of the new surgical technique is interlaminar osteotomy of the sub- Balint Molnar (Hungary), Sofia Aroca, Tibor Keglevich, Peter Windisch, Giovanni antral parts of the alveolar ridges in a horizontal plane. The lower part of the E. Salvi, Anton Sculean fragment, which includes the mucous membrane and the compact bone layer, forming the floor of the maxillary sinus, will be shifted upwards, thus creat- Objectives: The aim of this prospective, randomized, controlled split-mouth ing the subantral space. The subantral space was filled with bone substitution clinical trial was to compare the treatment of Miller Class I and II multiple material coupled with autogenous bone. gingival recessions using the modified coronally advanced tunnel (MCAT) tech- results: The sample consisted of 221 patients and 657 posterior maxillary im- nique by means of either a bioresorbable collagen matrix or a connective tissue plants. The mean duration of follow-up was 22.50+19.06 months. The 5-year graft (CTG). survival rates for implants in the ungrafted and grafted posterior maxilla were Methods: Seventeen subjects in good general health exhibiting multiple Miller 88.00% and 87.8%, respectively (P=0.8).Endoscopic analysis after 6 months Class I and II gingival recessions (i.e. at least 3 recessions per site) were includ- didn’t show any signs of pathological changes in the sinus area. This method ed and treated. According to a computer-generated randomization schedule, received a patent - 2260391 in 20.09.05; more than 200 patients have been op- recession sites were treated using the MCAT technique by means of either a bio- erated on using this method since 2005. resorbable collagen matrix (Mucograft®, Geistlich, Wolhusen, Switzerland) (test) Conclusions: The suggested modification helps to decrease the risk of damaging or a CTG harvested from the palate (control). The following clinical parameters the mucous membrane of the maxillary sinus; it creates optimal conditions for were assessed at baseline and at 1, 3, and 6 months postoperatively: recession performing reparative osteogenesis and implant osseointegration procedures. depth and width, width and thickness of keratinized tissue, distance from the tip of the papilla to the contact point, papilla width, probing pocket depth. results: No allergic reactions, soft tissue irritations or matrix exfoliations 247 i Strategy For Management Of infectious Tooth Extraction occurred at test sites. Mean root coverage amounted to 1.2 ± 0.4 mm at test Site in aesthetic implant Therapy: Combined usage Of Bio-Oss sites vs. 1.5 ± 0.6 mm at control sites. The mean increase in keratinized tissue Collagen and platelet-rich Fibrin width amounted to 0.2 ± 0.4 mm at test sites vs. 0.5 ± 0.6 mm at control sites. Complete root coverage was found in 52% of test sites vs. 72% of control sites. Hui Wu (China), Lin-xin Qiu Duration of surgery and patient morbidity were statistically significantly lower in the test compared to the control group, respectively. Objectives: The outcome of implant therapy is no longer measured by the im- Conclusions: hese outcomes indicate that: i) treatment of Miller Class I and II plant survival rate alone, but also by long-term aesthetic and functional suc- multiple gingival recessions using the MCAT technique combined with either cess. However, loss of an infected tooth in the aesthetic area usually causes Mucograft® or CTG may result in substantial mean root coverage, but lower hard and soft tissue defects which can lead to an unsatisfactory restoration complete root coverage with Mucograft® and ii) Mucograft® may represent a result. So the question of how to prevent ridge resorption and gingival reces- valuable alternative to the palatal connective tissue graft, resulting in lower sion has become a universal concern. Various graft materials have been used patient morbidity and duration of surgery. The present study was supported by in attempts to preserve the alveolar ridge following tooth extraction. Among a grant from Geistlich, Wolhusen, Switzerland. these materials, bovine bone mineral displays osteoconductive properties forming an effective bone/graft matrix for implant placement. But little was known about it in infected tooth extraction sites in aesthetic implant therapy. 249 i The Comparison Of Efficacy and Stability Of Vertical Thus the purpose of this study was to evaluate the clinical result of combined Bone augmentation after ddBM+hrpdGF, Bone Ceramic+EMd, usage of Bio-Oss collagen and PRF in infected tooth extraction sites, and to in- and allogenous Bone+ Natix around The implants vestigate the indication, surgical technique, and the implant time of this socket preservation method. andrej Wojtowitz (poland), Jan Perek, Kaminski Artur Methods: From Jul 2006 to Jan 2010, 21 patients were enrolled in this study, 13 male and 8 female, average age 36. 23 infected teeth in the aesthetic area were Objectives: A bone regeneration process was described recently by Urist and extracted and socket was preserved immediately with Bio-Oss collagen and Huggins. The key factors are: cells, growth factors (BMPs) and blood stream. PRF, including 15 central incisors, 4 lateral incisors, 2 canines and 2 premo- The advanced bioengineering methodology: stem cells, human recombinant lars. Panoramic radiograph and periapical films were taken to observe bone factors, invented scaffolds were used for bone augmentation in jaw bone de- healing and osseointegration. At the time of implant, a core biopsy was taken fect treatment. Five advanced “hybrid” techniques, based on tissue engineer- from the centre of the extraction site with a trephine bur (D 2 mm) and then ing, using scaffold with or without growth factors were present and compared histomorphometrically observed. The bone healing time, implant type, initial with the effects of stimulation of osteogenesis/resorption = remodelling of stability and graft surgery were recorded with statistics. alveolar bone by transplants: 1. DDBM with hrPDGF (Bio-Oss+/-Gem21S) results: 23 teeth were extracted and bone graft healing took place uneventful- 2.DDBM without GEM21 S, 3. Bone Ceramic with Emdogain, 4. Bone Ceramic ly. All sites were clearly different from the original alveolar crest, allowing the without EMD, 5. Tigran+allogenous cortical bone granules, processed in tis- retrieval of samples from the socket centre. The average diameter and length sue bank (Central Tissue Bank, Warsaw Medical University, Ethics committee of 23 implants was 3.8±0.3 mm and 13.2±1.7 mm. The thickness of 7 implants agreement). labial lamina was less than 1 mm, then GBR surgery was undertaken (30.4%). Methods: The “hybrid” transplants were installed together with implants dur- Others were thicker than 1 mm(69.6%). 6 of them were given connective tissue ing one-step surgery and consisting of bone transplant around 5–7 implants transplantation because labial fullness was poorer than on the contralateral each in five groups of the male patients (age 40-65) for measurements. Trans- side(26.1%). 10 were given only implant surgery(43.5%). 3 of them had early plants were applied in the maxilla aesthetic area, where all implant sites were placement with soft tissue healing (type 2, typically 4 to 8 wk of healing), 16 covered up to the bone level approx 1- 1.5 mm of the anterior site of the im- teeth positions had early placement with partial bone healing (type 3, typically plant, the posterior site was covered by jaw bone. 12 to 16 wk of healing), 4 implants had placement after more than 4 months be- The correlation of bone profile (Straumann Bone Profile Device) and ISQ-Ostell cause of orthodontic treatment. In all implants initial stability was higher than in time-intervals: 1/2, 3, 6, 12, 24 months were measured and evaluated. The 30 Ncm, 7 of which were higher than 40 Ncm and had immediate restoration. implant’s survival rate and implant’s success rate as well as recession rate Conclusions: As infected tooth with bone defect in the aesthetic area, preser- were evaluated clinically. The Ostell-ISQ provides objective and non-invasive vation of fresh socket immediately by the combined use of Bio-Oss collagen measurements of the implant stability at the placement as well as during the and PRF could preserve the contour of the ridge effectively and provide good healing and bone maturation period. bone volume and quality for aesthetic implant therapy. It could make clinical results: Two implants were lost. The implant success rate was 96%. The high- manipulation easy, reduce expense, shorten the treatment period and reduce est decrease in bone profile was found where bone ceramic was applied. There patient trauma, so it will have a wide clinical application. were no significant differences when bone ceramic was enriched by EMD. The50
    • clinical reSearch, clinical StudieSannual loss of bone profile around the implant was approximately 20 % of the 252 i The role Of pericranium in The prevention Of Woundvolume. In this group the smallest implant success rate were found, as well as Complication and implant Survival Following reconstructionhighest bone-gingival recession around the implants. Of Severely deficient Edentulous ridgesThe best implant success rate was found when tigran and allogenous-corticalbone were used. Similar results were reached for DBBM + hrPDGF, significantly alberto Coggiola (italy), Matteo Chiapasco, Elena Corsibetter when enriched by hrPDGF added into the transplant. Newly formed boneaugmented under influence of Tigran and cortical allogenous bone shows the Objectives: To evaluate the influence of pericranium used for the coverage ofmost stable results and closest similarity to the Bio-Oss with GEM 21 S. Tigran autogenous bone grafts for the reconstruction of severely atrophic jaws on: a)is not a carrier, it is a unique stable x-ray marker for bone augmentation. The the incidence of wound dehiscences; b) the survival rate of implants placed; c)process between bone and titanium interface is very well known and described. peri-implant bone resorption; and d) the incidence of peri-implantitis.Conclusions: It seems that application of growth factors (GF) is more effective Methods: 34 patients presenting with severely atrophied edentulous ridges werethan guided bone regeneration (GBR) of jaw bone, especially in the vertical reconstructed with autogenous bone blocks. In 16 patients (control group) theplane. It is very probable that EMD as a non-recombinant, but isolated factor is grafts were covered with a collagen membrane, while in 18 patients (test group) arapidly released from the scaffold environment and has a lower or incidental layer of pericranium was placed over the collagen membranes covering the bonebiological activity in comparison with potent recombinant hrPDGF. The adhe- blocks. Four to 5 months later, 178 implants were placed in the reconstructedsion of GF to titanium is not known, but the highest affinity of GF to the surface areas and prosthetic rehabilitation was started 3 to 4 months afterwards. Theof natural mineral is well described. mean follow-up of patients after the start of prosthetic loading was 31 months. results: The incidence of dehiscences was 5% in the test group and 12% in the control group, while peri-implantitis occurred in 5% and 25% in the test and250 i Treatment Of Bisphosphonate-associated Osteonecrosis control groups, respectively. Peri-implant bone resorption and implant survivalOf The Jaw With Mesenchymal Stem Cells rates did not show statistically significant differences between the two groups. Conclusions: The use of pericranium may reduce the incidence of dehiscencepit Jacob Voss (Germany), Rainer Schmelzeisen, Egle Veigel, Eva Jablonka, after reconstruction of atrophic ridges as well as the occurrence of peri-im-Marc Metzger, Sebastian Sauerbier plantitis, while it seems to have no effect on peri-implant bone resorption and survival rate of implants placed in the reconstructed areas.Objectives: Bisphosphonate-associated osteonecrosis of the jaws (BP-ONJ) isa clinical problem with well described morbidity, especially when given intra-venously. Surgical management with necrotomy is often required where con- 253 i long-Term results Of Hard Tissue reconstructionservative management has failed, but is not without the risk of relapse. The using alloplastic and autologous Grafts – What did We learnrole of marrow derived mesenchymal stem cell (MSC) grafting in promoting in The last 15 years?wound healing is well described. The aim of this study was to assess the role ofMSC in the management of BP-ONJ. yorck zebuhr (austria), Dusan Kosarevic, Gert SantlerMethods: In a pilot study, 8 patients with refractory BP-ONJ were managedwith surgical resection of necrotic bone followed by MSC grafting. Marrow de- Objectives: Hard tissue regeneration and reconstruction came into focus asrived cells were aspirated from the iliac crest and concentrated using a chair- dental implantology developed to a standard method of rehabilitation. The aimside bone marrow concentration procedure to obtain MSC. MSC were then was to use implant rehabilitation methods in the osseous compromised situ-grafted into the defect with autologous thrombin and a Bio-Gide membrane. ation as well. Originating from autologous procedures, xenogenous materialsIn all cases bony edges were rounded and the wound was closed using a three had the effect of reducing donor site morbidity.layer technique. Methods: Retrospective analysis of consecutive alveolar augmentation proce-results: At 12-15 months follow up, all patients showed satisfactory healing dures from a maxillofacial unit in the years 1995–2000 regarding primary out-with no signs of wound-infection, dehiscence or recurrence of BP-ONJ. Only comes and long-term results focusing on stability of the primary osseous andone patient developed significant complications, i.e. sepsis of unknown origin, prosthodontic/implant reconstruction.two months postoperatively. results: The majority of osseous and prosthodontic reconstructions have goodConclusions: This pilot study into the surgical management of refractory BP- primary and long term outcomes. Problematic cases were re-evaluated andONJ with mesenchymal stem cell grafting seems to be a promising treatment investigated for risk factors.modality. Our results suggest that further prospective investigation is warranted. Conclusions: Hard tissue grafting is a safe procedure and results are stable even in the long term.251 i a pilot Study To Evaluate Safety and Effectiveness Of NaturalBone Block Mineral For Bone augmentation Of One-Tooth-Gaps 254 i Maxillary Sinus Grafting With (NanoBone®) Hydroxyapatite Embedded in a porous Silica Gel Matrix in Humans: Histological,Simone Heuberer (austria), Ela Balic, Stefan Tangl, Georg Watzek Histochemical, and Histomorphometric resultsObjectives: The aim of the pilot study was to use natural bone block mineral for dieter Bosshardt (Switzerland), Jean-Pierre Carrel, Michael Bornstein, Danielhorizontal ridge augmentation of single tooth gaps. Two patients of the Bernhard Buser, Jean-Pierre BernardGottlieb School of Dentistry, Vienna, Austria, were involved in this pilot study.Methods: Patients with an insufficient ridge width of a single tooth gap and of Objectives: To evaluate the amount of new bone after sinus floor elevation witha good general health were included. Augmentation was achieved with a hy- a synthetic bone substitute material consisting of hydroxyapatite embeddeddroxyapatite- and collagen- containing natural bone block mineral, which was in a porous silica gel matrix (NanoBone®/NB), since information is scarce infixed onto the decorticalized vestibular bone wall and covered by a collagen humans when new biomaterials are used.membrane. Clinical and radiographic examinations were performed; bone core Methods: The lateral bone window approach was applied in eight patients re-biopsies were histologically analyzed. quiring a sinus floor elevation procedure to install dental implants. After eleva-results: The primary parameter was implant placement after 16 weeks of heal- tion of the Schneiderian membrane, the cavities were filled with 0.6 mm gran-ing and the outcome was positive. No material-related adverse effects were en- ules of NB mixed with the patients’ blood and a collagen membrane (Bio-Gide®;countered. group 1) or a platelet-rich fibrin (PRF) membrane (group 2) was placed over theConclusions: Discussion: After 16 weeks of healing the bone within the defects bony window. After 7–11 months of healing (in one case after 24 months), 16was not yet corticalized and narrow implants were used. Conclusion: Manage- biopsies were harvested during implant bed preparation. After aldehyde fixa-ment of demanding defects such as ridge augmentation with a volume stable tion, the samples were decalcified in EDTA and embedded in LR White resin.natural bone block mineral has to be further investigated and optimized for Sections were stained with basic fuchsin and toluidine blue. The percentagethe clinical use. of new bone, residual filler material, and soft tissue was determined histo- 51
    • morphometrically. In addition, sections were histochemically treated to detect through visits that were scheduled for 1 and 12-month intervals during the tartrate-resistant acid phosphatase (TRAP) enzyme activity, normally being as- first postoperative year and annually or bi-annually thereafter. At each recall, sociated with osteoclast-like cells. clinical and radiographic examinations of the sinuses and implants, including results: Four biopsies had to be excluded from the analyses, since only old computerized tomography (CT), were performed. bone from the residual ridge was contained in the trephine due to incomplete results: Ten of 101 implants were lost, giving a cumulative survival rate (CSR) tissue retrieval. In the augmented region of the remaining 12 biopsies, new bone of 91.1%. All lost implants were substituted and all followed patients had fixed formed a dense network of evenly distributed bone trabeculae interconnect- prostheses functioning after 5 years of loading. ing with neighbouring NB particles, which were structurally non-homogeneous Conclusions: This study suggests that the installation of implants after the and appeared porous. Numerous TRAP-positive multinucleated cells were sinus lifting procedure combined with deproteinized bovine bone (Bio-Oss®) mainly observed at the soft tissue-NB interface. For group 1, the amount of new grafting in cases with pneumatization of the posterior maxilla have great bone, residual filler material, and soft tissue was 28.7%±5.4, 25.5%±7.6, and predictability and high survival rates. Therefore, these procedures represent 45.8%±3.2, respectively. For group 2, the corresponding values were 28.6%±6.9, a reliable option for the treatment of patients and enable clinicians to place 25.7%±8.8, and 45.7%±9.3. All differences between groups 1 and 2 were not sta- implant-supported prostheses even in cases with increased pneumatization of tistically significant. The lowest and highest values of new bone were 21.2% and the maxillary sinus with atrophic alveolar bone. 34.1% for group 1 and 17.4% and 37.8% for group 2, respectively. Conclusions: The amount of new bone after the use of NB for sinus floor eleva- tion in humans is comparable to the highest values found in the literature for 257 i augmentation Of alveolar ridge after other synthetic or xenogeneic bone substitute materials such as Straumann Comminuting Fractures With distraction Osteogenesis BoneCeramic® or Bio-Oss®. Concerning the amount of new bone, there was no additional beneficial effect of the PRF membrane over the Bio-Gide® mem- Miha kocar (Slovenia), Andrejka Eberlinc, Andrej Kansky, Vojko Didanovic brane. TRAP-positive osteoclast-like cells appear to be involved in the degra- dation of the synthetic biomaterial. Objectives: Distraction osteogenesis (DO) is an established method to gain al- veolar bone in the alveolar ridge. Comminution of the alveolar ridge is often associated with fractures of the upper and lower jaw. The aim of the study is to 255 i radiographic Evaluation Of Marginal Bone levels find out if DO is an appropriate surgical procedure to gain bone for reconstruc- Following immediate implant placement into Extraction Sockets tion with dental implants. Methods: Reconstruction with DO was performed on four patients (2 male, Nobuyoshi Sugioka (Japan) 2 female), average age was 25 (18–34). Comminution of the alveolar ridge (3 mandibles, 1 maxilla) with loss of teeth (4–6) was present in all. After the heal- Objectives: The aim of this prospective study was to evaluate the amount of ing period and due to jaw fractures, clinical and x-ray examination was carried buccal/palatal bone loss that occurred over 1 year of healing following their out. It was found out that 8 to 14 mm of bone needed rehabilitation. Temporary installation into extraction sockets using cone-beam computed tomography. partial dentures were delivered preoperatively. Under general anaesthesia, Methods: In 26 subjects, single-tooth implants were placed immediately into osteotomy and fixation of distractors (Medartis) were performed. Bi-or mono- extraction sockets in the maxilla (tooth locations 15/25). After implant instal- directional (2/2) distractors were used depending on the clinical need. Distrac- lation, a series of measurements were made to determine the dimension of tion started 10 days later, 0.5 to 0.75 mm per day. In 2 cases, buccal angulation the ridge using cone-beam computed tomography and the void between the of the distracted segment was added at the end. According to the protocol, implant and the extraction socket. These measurements were repeated in the panoramic radiographs were performed. The consolidation period lasted 16 re-entry procedure over 1 year. weeks, distractors were removed and 12 dental implants (Ankylos, Dentsply- results: The implant survival rate was 100% for all 26 implants. The study dem- Friadent) were inserted. Implants were uncovered 4 months later and fixed onstrated that the removal of single teeth and the immediate placement of an prosthetics were delivered. implant resulted in marked alterations of the dimension of the buccal ridge and results: With DO 9 to 15 mm of bone deficiencies was gained and gave us the horizontal as well as the vertical gap between the implant and the bone walls. conditions for rehabilitation with dental implants. Bi-directional distractors Conclusions: Implant placement into extraction sockets will result in significant gave us the opportunity to correct distracted segments in a better position. bone reduction of the alveolar ridge. In any case, no extra augmentation procedures were needed. Implantations were performed immediately after the consolidation period, 8/4 implants of 17 mm/14 mm in length. All of them were osteointegrated. 256 i retrospective Study Of 101 implants Conclusions: All 4 cases with DO vertical deficiencies of the alveolar ridge were inserted in augmented Maxillary Sinus anatomically corrected. Use of bi-directional distractors made the correction of the buccal-lingual vector possible. The established height of the alveolar Joao antonio dosualdo (Brazil) ridge made the insertion of dental implants possible. Partial dentures were used for additional stabilization of the osteotomized segment. Objectives: The aim of the present study was to evaluate bone formation fol- lowing maxillary sinus augmentation using bovine bone substitute material Bio-Oss® and to determine the rates of long-term success and current radio- 258 i Hard and soft tissues protection in immediate graphic images of the implants installed after the sinus lifting procedure and to VS delayed implant placement analyze the modification/alteration of the grafting images in a case of maxillary sinus augmentation, recording and comparing radiographic images at 1 week, Wang ying (China), Ye Lin, Bo Chen, Linxin Qiu, Yu Zhang, Hui Wu 2 months, 8 months, 1, 2, 5 and 10 years after surgery. This long-term evaluation has been performed comparing radiographic im- Objectives: Immediate placement of implants has been found to have a high ages at different times and involved a total of 58 sinus floor elevation pro- rate of success. It was shown that major changes in an extraction site occur cedures, carried out on 36 patients (average age of 49.6 years) according to in the first 3 months after tooth extraction. While many researchers believe the technique described by Tatum (1986) and a total of 101 dental implants that delayed implant placement for anterior teeth is more predictable for the inserted. esthetic result. This study is to observe the clinical result of immediate implant Methods: Between July 2000 and December 2010, a total of 101 implants were and delayed implant. installed in 36 patients (12 men / 24 women), who were aged between 45 and 83 Methods: Group 1: Immediate implant years (average: 60.2 years), in which the surgical procedure of the sinus lifting 9 Patients presented untreatable anterior upper teeth. Cone Beam CT were technique were consecutively enrolled on edentulous ridge bone (less than 4 took before surgeries. Teeth were extracted without flap reflection, and im- mm). Straumann SLA® implants were placed after 8 months of graft healing. plants (Nobel Biocare Replace/Ankylos) were inserted simultaneously. Bio- After another 3 months, the occlusion was restored with fixed prostheses and Oss granules and Bio-Gide membrane were used to fill the gap between the followed at least for 5 years of functional loading. All the patients were followed implant and the bone wall. Mattress suture was adopt on both sides of the52
    • clinical reSearch, clinical StudieShealing abutment to achieve the primary wound closure. Cone beam CT was ways performed when the bone height was less than 9.5mm, using the modi-took after 6 months from the day of implants placement. fied lateral window technique by Kent and Block in combination with resorbableGroup 2: Delayed implant membranes. Bovine hydroxyapatite (Bio-Oss® Geistlich and Sons, Wolhusen,5 patients presented two untreatable anterior upper teeth. We follow the de- Switzerland) was used to augment the sinus. A two-stage procedure was usedlayed implant protocol. Teeth were extracted with bone (Bio-Oss/Bio-Oss Col- in patients with a preoperative bone height of less than 5mm. A bone graft hadlagen)graft. Implants (Nobel Biocare Replace/Ankylos) were placed following a healing period of 8 to 9 months before implant insertion. One-stage proce-two stage protocol with guided bone regeneration (Bio-Oss granule and Bio- dure was used when bone height exceeded 5mm and the bone was sufficientGide membrane) after 3 months. 6 months after the implant placement, heal- for implant insertion. The first visit included medical, dental status, a completeing abutments were placed. Cone bean CT was took after 6 months from the oral exploration and radiographic examination. All implants were inserted asday of implants placement. late implants more than 3 months after healing.results: Through the comparison of the 3D-CT pre-op and post-op, the alveo- results: 34 Frialit II implants were failures. 4.9 % of 683 Frialit II implants werelar bone was preserved very well on both groups. The gingival margin level and lost and show an overall survival rate of 95.0 %. 4 Xive implants (0.5%) failed andthe papilla are quite favorable on both groups. On the second group, during the the survival rate for Xive implants was evaluated with 99.7%. Sinus proceduresearly months after teeth extraction, the papilla showed different level absorp- were evaluated to have a negative effect on primary stability measured withtion, while recovered spontaneously after delivered provisional crowns. Torque-Controler®. For both types of implants a statistical significance was as-Conclusions: Both two cases got optimize esthetics means both two protocols sessed (p‹0.001). Frialit II® implants which were inserted after a delayed healingcan achieve optimized esthetics. Immediate implant shows more time-saving, period of the sinus augmentation showed a lower mean insertion torque thanwhile delayed implant shows more time-consuming, and complicated. We rec- Frialit II® implants which were inserted simultaneously with a sinus augmenta-ommend Bone grafts combine with membrane technique for both immediate tion (p‹0.002). Xive® implants didn´t show a statistical significant effect for theseimplant and delayed placement. Long-term prospective studies on tissue sta- two different situations (p‹0.108). At second stage surgery mean PTV value ofbility and esthetic outcomes are needed in the future. Frialit II implants was -3.8 and showed a statistical significant difference to Xive implants with a mean PTV value of -5.43 (p‹0.001). Conclusions: Promising long-term outcomes were observed for implants with259 i implant location and related primary and secondary stability sinus floor elevation with bovine hydroxyapatite. Even if sinus procedures have a negative effect on primary stability, survival rates of Frialit II and Xive im-Volker Clar (austria), Alexander Heschl, Susanne Platzer, Michael Payer, Martin plants placed in combination with sinus augmentation are comparable to sur-Lorenzoni, W.A.Wegscheider vival rate of implants placed without a maxillary sinus floor elevation.Objectives: The objectives of our study were to evaluate the different meaninsertion torque and Periotest values for the jaws, to show correlations to dif- 261 i an Operator error: a risk factor for implant lossferent indications and to determine the accuracy to document implant stabilityand to show possible predicting capacity for early implant failures. Mehnaz kamali (united arab Emirates)Methods: The present study was conducted as a retrospective non-controlledsingle centre trial. 475 males and 706 females (3123 Xive and Frialit II implants) Objectives: To investigate the reasons for immediate implant loss. To investigateunderwent implant rehabilitation and their collected data was used for our study. the reasons for implant loss during healing period. To investigate the risks fac-All implants were inserted as late implants more than 3 months after healing. tors associated with implant loss at 3 stages (Immediate loss, implant loss duringThe implants were placed with an increasing counter-torque (Torque-Controler, healing and implant loss following healing). To investigate clinical errors leadingNobel-Biocare, Gothenburg, Sweden). The Periotest was used according to the to forced explanation in cases with good primary stability at time of placement.manufacturer´s instructions during second stage surgery. The insertion torque To investigate common surgical errors causing lack of primary stability. To inves-and Periotest values were documented and the mean values were evaluated. tigate patient related factors causing lack of primary stability. To investigate im-results: Early failures were found for 7 Xive® implants (0.3 % of 2299 implants) plant design faults that can cause immediate loss despite good primary stability.and for 31 Frialit II® implants (3.8 % of 824 implants). For Frialit II implants Methods: Retrospective observational study of 63 lost and failed implants dur-it was evaluated that the group with lower insertion torque than 45 Ncm the ing 2009 at Dubai Health Authority. Approval to conduct the study was obtainedfailure rate was higher (p‹0.011). Xive implants didn´t show a difference, but internally from the Dental Centre at Dubai Health Authority.the failure rate was very low for calculations. Mean insertion torque values for Sample population: All implants which were lost following surgical placementFrialit II® implants were the lowest in the maxilla followed by the mandible. For during 2009 were included in the study. Time of implant loss was categorizedXive® implants the same finding could be assessed. Sinus procedures were as immediate loss, loss during healing period and loss following healing pe-evaluated to have a negative effect on the primary stability (p‹0.001). Length riod. The implant systems used at DHA were 3 different types of Friadent Im-and diameter didn´t show a statistical significant influence on neither insertion plants: Xive, Ankylose and Frialet. Data collection was completed from com-torque nor Periotest value (r=0.092; r=0.055). Periotest was statistical signifi- puter based clinical records and from digital x-rays as well as implant surgicalcant higher for the failure group (p‹0.001). Implants inserted in the mandible and failure forms. Clinical Errors were categorized into: Implant planning and(anterior›posterior) showed higher mean Periotest® values than the implants selection errors and surgical skill related errors. Additional patient relatedplaced in the maxilla (anterior‹posterior) (p‹0.001). factors and implant design factors were also investigated for comparison. AllConclusions: The present clinical study illustrates that insertion torque and clinical procedures followed during the surgical placement were investigatedPeriotest value are both useful noninvasive systems to measure implant sta- and recorded and their association with the different stages of implant loss wasbility. Early implant failure can be predicted, but the sensitivity of both instru- calculated in the form of percentages. Data were entered in excel sheet andments is too weak to rely just on their measurement. percentages were calculated and presented in tables and charts. results: The total number of 547 implants was placed by 10 different opera- tors. The total number of 61 was lost implants. 62% of implants were lost due260 i a clinical study of bovine hydroxyapatite in maxillary sinus floor to poor primary stability while 36% of those lost were had good primary stabil-elevation – results after a maximum observation period of 15 years ity and were lost due to different factors. Factors that resulted in poor primary stability included surgical skill related errors such as incorrect stage of im-Volker Clar (austria), Alexander Heschl, Susanne Platzer, Michael Payer, plant placement (Immediate and early placement) and implant selection errorsMartin Lorenzoni, W.A.Wegscheider including incorrect implant size selection, incorrect implant length selection, and incorrect placement techniques and implant placement with initial highObjectives: The objective of our study was to investigate the effect of a de- torque. 60% the implants were lost immediately at the time of placement. Theproteinized bovine bone mineral on long term survival and implant stability of frequency of loss reduced as the healing period progressed. 70% of those lostFrialit and Xive implants placed in combination with a sinus lift. immediately were due to lack of primary stability. Those which were not lostMethods: 1462 implants (683 Frialit II and 779 Xive implants) were placed in due to poor primary stability were lost due to implant design faults and due tocombination with a maxillary sinus augmentation. A sinus bone graft was al- operator related surgical skills in implant placement such as implant posi- 53
    • tioning and angulations errors. 36% of the total lost implants were explanted 1. determine local temperature changes in bovine rib bone during 50 implant during the healing period and only 23% of the latter were due to poor primary site preparations using a twisted stainless steel drill and a ceramic drill, at stability. Factors that lead to implant loss during healing period were due to depths of 8 and 10 mm; patient related factors. 95% of all lost implants were prior to functional loading 2. evaluate drill wear after 50 implant site preparations by means of scanning and the additional 5 % were explanted on re-entry (second stage) electron microscopy (SEM). Conclusions: Operator errors such as poor surgical handling, positioning er- Methods: Twelve bovine bones were cleared of all soft tissue and frozen in sa- rors and incorrect implant size/length selection may lead to immediate im- line solution at -10° C. Prior to use, the bone were sectioned in blocks . Fifty plant loss and replacement during surgical procedures. Theses factors are less implant site preparations were performed on these bone blocks using a sur- frequent in cases were implant were lost during healing period. In the latter gical unit linked to a testing device in order to standardize/simulate implant additional factors related to implant design as well as patient related factors drilling procedures. Constant irrigation at 50ml/min. (21°±2°C) and a drilling becomes more important. The fact that 95% of the implants were lost prior to torque of 800 rpm were used. During each implant site preparation the fol- functional loading confirms that surgical related factors have a significant ef- lowing data were recorded: room temperature, bone baseline temperature, fect on the outcome of implant surgery. As a result operator skills in implant maximum bone temperature recorded at 8 mm and 10 mm, maximum load type selection and surgical placement skills greatly influence the successful applied during drilling up to 8 and 10 mm and total preparation time. Bone placement of implants. Implants are costly operations and all steps must be temperature variation was calculated at both depths in each perforation and carefully planned to avoid costly errors. Patients with high risk factors must relative to each previous recorded bone baseline temperature. be assessed and strict protocols must be implemented to ensure long term Scanning electron microscopy was performed prior to and after drilling. success. results: The mean temperature increase for the stainless steel drill was 0.8°C and 2.2°C, and for the ceramic drill 0.7°C and 1.8°C at depths of 8mm and 10mm respectively. Significantly higher bone temperatures were obtained with both drills at depths of 10mm (P < 0.05). The temperature increase was cor- _ related with the number of perforations (P < 0.05).There was no significant _ difference in temperature rise when comparing both drills, and no association between temperature and the drilling force applied. Significantly higher forces BaSiC rESEarCH, iN ViTrO STudiES were used when drilling with the stainless steel drill at both depths. No severe signs of wear or deformation were detected after 50 uses. Conclusions: Both drills can be used up to 50 times without producing harm- ful temperatures to bone tissue or severe signs of wear and deformation. Drill 301 i recombinant Human Bone Morphogenetic protein-2 material and design appear to influence cutting efficiency, but do not produce (rhBMp-2) delays The differentiation Of Osteoblast-like Cells significant temperature variations with the drilling protocol applied. Drilling Grown On Titanium Surfaces depth was a predominant factor in bone temperature variations during implant site preparations. adriane yaeko Togashi (Brazil), Fabiano Cirano, Marcia Marques, Francisco Pustiglioni, Luiz Antonio Lima 303 i a Single-Species Biofilm Model Objectives: The aim of this study was to assess the influence of the chemical To Evaluate implant Cleaning Strategies characteristic and roughness of titanium surfaces on osteoblast-like prolif- eration and differentiation cultured in medium added to bone morphogenetic Haiyan lin (China), Dongmei Deng, Yuelian Liu, Daniel Wismeijer, Wim Crielaard protein-2 (BMP-2). Methods: Osteo-1 cells were grown on titanium discs with the following sur- Objectives: Implant cleaning is a crucial step in successful bone regeneration in faces: 1) machined surface, 2) coarse grit-blasted and acid-etched (SLA) and patients with perimplantitis. For the development of efficient implant cleaning 3) modified SLA (SLAactive) in the absence or presence of rhBMP-2 20ng/ strategies, a reproducible, high throughput, in vitro biofilm model is urgently need- ml in culture medium. Osteo-1 proliferation was evaluated at 24 hours. Cell ed. The aims of this study are to establish a single-species biofilm model and test differentiation was evaluated by total protein content (PT), collagen content its reproducibility in biofilm growth and in response to antimicrobial treatments. and ALPase activity assays at 7, 14 and 21 days and mineralized matrix for- Methods: Streptococcus mutans biofilms were formed on the surfaces of tita- mation at 21 days. Data were compared by analysis of variance (ANOVA) and nium discs with different degrees of roughness in 24-well microtiter plates. The Tukey test. biofilm medium was refreshed every 8h and 16h. One day and three day old bio- results: Cell proliferation (p=0.0936) and mineralized matrix formation films were treated with sterile water or 0.2% chlorhexidine for 10 min. Biofilm (p=0.0456) were not affected by different surfaces or by the addition of rhBMP-2 viability was evaluated by colony forming unit (CFU) counts. Each experiment was to the medium. Osteo-1 cells cultured on SLA surface showed a significant repeated 3–4 times and in each experiment, 3–4 replicate samples were included. increase in total protein content at 21 days. Collagen content was not affected results: Up to 48 independent biofilms could be formed on the titanium discs by different surfaces or by the addition of rhBMP-2 to the medium at 14 and 21 in one experiment. Good reproducibility in CFU counts was observed; the coef- days. ALPase/PT ratio (p=0.0000) was affected by treatment and time. ficients of variance (CV) were within 2% irrespective of the age of the biofilms Conclusions: he results suggest that the addition of rhBMP-2 to the culture and the roughness of the substrate. Ten minutes of chlorhexidine treatment medium did not have any effect on osteoblast proliferation and delays the dif- significantly reduced biofilm viability. However, reproducibility was decreased, ferentiation of Osteo-1 cells grown on surfaces of different degrees of rough- being 70% for 1-day old biofilms and 8% for 3-day old biofilms. It was noticed ness at each point in time. All tested surfaces of titanium allowed an expres- that the CFU counts of 1-day old biofilm after chlorhexidine treatment was sion of osteoblast phenotype-like matrix mineralization by Osteo-1 cells. close to the detection limit (100 CFU/disc). Conclusions: This S. mutans biofilm model is a high throughput model. It shows good reproducibility in growth but lower reproducibility in response to 302 i Thermal Changes in Bovine Bone during treatments. Increasing numbers of replicate samples should be considered in implant Site preparation. a Comparative in Vitro Study: implant cleaning evaluation for this type of biofilm model. Twisted Stainless Steel and Ceramic drills Natália Oliveira (Spain), Fernando Alaejos-Algarra, Javier Mareque, Eduardo 304 i Tissue Engineering Strategies For The in Vitro Ferrés-Padró, Frederico Hernandez-Alfaro reconstruction Of dental pulp-like Tissue: The role Of dental pulp Stem Cells and Growth Factors Objectives: The purpose was to assess thermal changes in bovine bone tissue with the use of twisted stainless steel and zirconia-based drills during implant Stefano Sivolella (italy), Eriberto Bressan, Gian Antonio Favero, Mario Berengo, site preparation, more specifically to: Letizia Ferroni, Barbara Zavan54
    • baSic reSearch, in Vitro StudieSObjectives: The most important function of dental pulp is to maintain tooth However, most studies have focused on metallic compounds and there havevitality by supplying minerals and organic materials. Injured pulp tissue may been few studies of organic materials. Our aim here was to examine the effectsundergo necrosis, prompting the need for endodontic and reconstructive treat- of nano vitamin C applied to the gingival fibroblast and to compare it to applica-ment or the extraction of the tooth involved. Several mechanical strategies tion of generic vitamin C.have been developed to preserve a healthy pulp in prosthetic and restoration Methods: To compare the size difference and physical characteristics of nano vi-procedures, but until now no 3D in vitro biological approaches have been at- tamin C and generic vitamin C, we use nano vitamin C made by Nanocuretechtempted. The aim of the present work was the in vitro reconstruction of a den- (Daejeon, Korea) and generic vitamin C made by Sigma-Aldrich (Chicago, IL, USA).tal pulp-like tissue by combining tissue engineering strategies with dental pulp Cell culture was carried out to examine the effect of vitamin C on fibroblast.stem cell biology as predictive tool for use in cytotoxicity testing. Fibroblast was taken from healthy gingiva and Dulbeccos modified Eagle’sMethods: Human-derived dental pulp stem cells (DPSCs) were seeded on to medium-high glucose was used for the culture medium.a hyaluronan-based scaffold and cultured for up to 21 days in differentiation MTT assay was performed to find the safety concentration of vitamin C, whichmedium enriched with neuronal and endothelial growth factors. Histological was prepared from 0.01 µg/ml to 50 µg/ml and observed for 24 to 48 hours.and molecular analyses were performed 3, 7, 14 and 21 days after differentia- Collagen assay and real-time RT-PCR were also checked in order to observetion in order to investigate the organization of the extracellular matrix and the the effect of nano vitamin C.neuronal and endothelial commitment of the cells. results: Scanning electron microscopy showed that generic vitamin C was 50results: Morphological analyses showed that DPSCs were distributed both on the times bigger than nano vitamin C and twice as large in solution.surface and within the three-dimensional construct. In particular, DPSCs grew There was no difference in MTT assay between the two particles. However, col-well inside the scaffolds, filling all the spaces between the fibres. Immunohisto- lagen synthesis was significantly increased by nano vitamin C in lower concen-logical staining and gene expression for the principal neuronal, endothelial, and tration compared to generic vitamin C. In particular, type I and type IV collagenextracellular matrix components confirmed the correct commitment of the cells. synthesis were significantly increased by nano vitamin C (P 0.001).Conclusions: Tissue engineering strategies can be used for the successful in Conclusions: Both nano vitamin C and generic vitamin C are effective in type Ivitro reconstruction of a dental pulp-like tissue with biological characteristics and type IV collagen synthesis. Nano vitamin C is more effective in lower concen-closely resembling those of natural pulp tissue. Such strategies may represent trations than generic vitamin C.an innovative approach to the in vitro study of how the dental architecture de-velops and a useful tool for use in screening for cytotoxicity. 307 i apical Bud Cell-Secreted Factors promote Odontoblast differentiation in Vitro and accelerate Mineralized Tissue305 i Comparison Of Clinical and Histomorphometric Bone Gains Formation in Human dental pulp Stem Cells in Vivoin Three dimensions Obtained From Bovine Cortical Bone Screwsand autogenous Onlay Grafts in dogs Beagles park Joo-Cheol (korea), Jihyun Lee, Won Jun ShonGuliherme piragine (Brazil), Marco Pontual, Hedilberto Sousa, Danielle Lima, Objectives: Epithelial-mesenchymal interaction is essential for odontoblastRicardo Magini, Leonardo Bez differentiation. However, the epithelial factors that control odontoblast dif- ferentiation are unclear. The aim of this study was to evaluate the effect ofObjectives: To compare newly formed bone after bovine cortical bone screw ameloblast on human dental pulp stem cells (hDPSCs) differentiation in vitroplacement and onlay autogenous bone graft procedure. and in vivo.Methods: Eighteen female Beagle dog tibias received 4 bovine cortical bone Methods: We isolated hDPSCs from human third molar and apical bud cellsscrews and an onlay autogenous bone graft. Both augmentation techniques (ABCs) from mouse incisors. After odontoblast co-culture with ABCs, we in-resulted in newly formed bone. Fluorchromatic bone markers were injected vestigated the effect of ABCs-SF on hDPSCs in vitro. Co-cultured odontoblastinto the dogs at different time intervals. Sections of the samples were analyzed and hDPSCs with ABCs were analyzed by real time PCR and western blot.by fluorescence microscopy 2, 4, and 6 months post-operatively. The fluoro- Alizarin red S staining was carried out to observe calcified nodule formation inchrome markers were alizarin, calceíne and tetracycline. odontoblast treated with ABCs-SF. To identify the effect of ABCs-SF on DSPPresults: Newly formed bone was observed in sections made of samples col- promoter, luciferase activity was measured. hDPSCs treated with ABCs-SFlected from both procedures. The bovine cortical bone screw was partially were transplanted to the subcutaneous skin of immune-compromised mice topresent in the samples and seemed to reduce in quantity as time intervals ex- confirm the effect of ABCs-SF on mineralized tissue formation in vivo. We alsotended. Additionally, the bone was contiguous to the receptor site. This could analyzed ABCs-SF using LC-MS/MS to find which factor affects odontoblastbe attributed to the bone neoformation. The autogenous onlay bone graft was differentiation and mineralized tissue formation in hDPSCs.gradationally substituted after being integrated into the receptor site faster results: Co-cultured hDPSCs with ABCs increased expression of dentin sia-than the newly formed bone, suggesting an osseoinduction and osseoconduc- lophosphoprotein (DSPP), but decreased bone sialoprotein (BSP). ABCs-SFtion characteristic. The newly formed bone was highly cellular, showing the treatment resulted in upregulation of DSPP promoter activity but downregu-presence of osteocytes and osteoclasts. Two months postoperatively, the corti- lation of BSP promoter activity in odontoblasts. Oral epithelial cell (KB-SF)cal bovine bone screw technique showed statistically significant bone forma- had no influence on DSPP promoter activity. Interestingly, transplantation oftion compared to the onlay bone graft. This finding was confirmed after analy- hDPSCs treated with ABCs-SF produced more mineralized tissue than the con-ses at intervals of 4 and 6 months. trol hDPSCs. Furthermore, the area of mineralized tissue formed in hDPSCsConclusions: The bovine cortical bone screw was shown to be highly osteoin- treated with ABCs-SF was similar to that formed with BMP2 treatment as usedductive. The authors suggest its use compares with that of onlay autogenous for positive control. BMP-related factors were not contained in ABCs-SF. Thegrafts for bone graft augmentation procedures. The bovine cortical screw used results of the ABCs-SF analysis showed the existence of various proteins withfor bone augmentation proved to be a better long-term solution than the on- extremely diverse locations and functions. In particular, copine 7, a moleculelay autogenous bone graft procedure, due to the higher bone resorption at the detected in the ABCs-SF analysis, increased odontogenic/osteogenic gene ex-onlay graft surgical site. pression in MDPC-23. Conclusions: These results suggest that ABCs-SF could promote the differen- tiation and mineralization of hDPSCs in vitro and bone formation in vivo. Taken306 i Comparative Study Of Nano Vitamin C application together, concentrated ABCs-SF would be applicable to regeneration of min-and Generic Vitamin-c application in Gingival Fibroblast eralized tissue. In addition, copine 7, a newly identified molecule in ABCs-SF, could be a new candidate factor in the modulation of odontoblast differentiation.dongju Choi (korea), JunWoo ParkObjectives: Current nanotechnology has developed for many different kinds 308 i promotion Of Early implant Healing Via Chemicalof materials. Examination of their physical and biological activities reveals and Biomimetical Titanium Surface Modifications –significant difference in the material characteristics of nano-sized materials. platelet activation and Cytokine release in Vitro 55
    • peer kämmerer (Germany), Matthias Gabriel, Thomas Scholz, Carl-Maximilian rodrigo Guerra de Oliveira (Brazil), Bianca Oliveira, Andre Dias, Plinio Ramos, Kirchmaier, Marcus Oliver Klein, Bilal Al-Nawas Leonardo Picinini Objectives: Platelet releasate has been shown to promote osteogenetic cell Objectives: Analyze through a systematic review of current knowledge the use proliferation and differentiation. The chemistry of biomaterials has a high im- of BMPs in surgery of maxillary sinus lifting and in human extraction sockets. pact on platelet activation. More specifically, the bioactive cell adhesive peptide Methods: Systematic review based on the MEDLINE (National Library of Medi- sequence Arg-Gly-Asp (RGD) triggers platelet activation mediated by the IIb3 cine) databases, without linguistic restrictions, using the following keywords: integrin receptor. Accordingly, chemical and biomimetical (immobilized RGD Bone morphogenetic protein, rhBMP-2, maxillary sinus lift and in human peptide) modifications of titanium (Ti) surfaces may enhance early platelet ac- extraction sockets. Only randomized controlled trials that used rhBMP-2 for tivation and bony healing of implants. Therefore, the aim of the study was to reconstruction of alveoli after tooth extraction and/or lifting of the maxillary evaluate platelet activation with subsequent platelet derived cytokine release sinus, published in the last ten years, were included. by accordingly modified Ti surfaces. results: We identified seven studies, of which only six were part of the scope Methods: Materials and methods: Acid-etched (A, Ra=0.83 µm, CA=106°) and of this review. The studies involved 362 patients, and were quite different in large grit sandblasted, acid-etched (SLA, Ra=3.2 µm, CA=109°) titanium surfac- terms of site, sample size, protein concentration, used vehicle, and registration es were investigated. Additionally, RGD peptides were chemically immobilized of clinical and radiographic data. Therefore, it was not possible to perform a on A and SLA surfaces (A-RGD (CA=0°), SLA-RGD (CA=0°)). The different Ti sur- meta-analysis of data obtained. faces were incubated with platelet concentrate from three healthy volunteers at Conclusions: From the data obtained in this systematic review it can be con- room temperature for 15 and 30 minutes. High thrombogenous collagen served cluded that the reviewed studies recommend the use of rhBMP-2 for recon- as a control group. Using the supernatant, platelet consumption was assessed structive treatment after dental extraction or vertical increase of maxillary si- via platelet count (PC). Cytokine release was quantified via the level of platelet- nus. The subject still needs further randomized controlled trials, as the paucity derived growth factor (PDGF) and vascular endothelial growth factor (VEGF). of scientific evidence was evident. results: After 15 min, the rough SLA surface in particular showed a strong de- crease in PC and a strong increase in VEGF and PDGF levels. After 30 min, high platelet consumption as well as high levels of VEGF and PDGF were measured 311 i Establishment Of Gingival Epithelial for A-RGD surfaces, indicating a delayed effect of the surface modifications on Wound Healing Models and Measurement Of The influence platelet activation. Of different ECM-Molecules On Wound Closure Conclusions: Modifications of surface roughness modifications seem to influ- ence early platelet activation and cytokine release after 15 min whereas sur- Thomas imhof (Switzerland), Stephanie Mathes, Ursula Graf-Hausner face modifications via RGD peptide on plainer surfaces lead to a further, more specific promotion of platelet activation and degranulation after 30 min. The Objectives: Oral soft tissue regeneration has become a main issue in the de- observed effect could be valuable for critical clinical situations such as com- velopment of substitute materials. But systems enabling the evaluation of bio- promised bone sites. materials in a simulated soft tissue wound are still rare. We present gingival models, which serve as appropriate tools for wound closure characterization. Methods: For the evaluation of cell migration the bottoms of well plates were 309 i Biomimetic Calcium phosphate Bone Filler coated with ECM molecules (Elastin, collagen I, fibronectin and collagen IV). With Coordinated delivery Of Multiple-drugs Immortalized human gingival keratinocytes were grown in a growth factor supplemented culture medium. The keratinocytes were seeded on the coated Tie liu (Netherlands), Yuanna Zheng, Gang Wu, Daniel Wismeijer, Yuelian Liu surface and they formed a cell monolayer. This monolayer was then wounded by scratching and the wound closure was monitored by the use of an auto- Objectives: The aim of this study is to develop a novel bone filling material that mated microscope. would be not only biodegradable and biocompatible, but also capable of coordinate- For the full evaluation of full thickness epithelial wound healing, gingival fibro- ly delivering multiple bioactive agents as a goal to heal voluminous bone defects. blasts were expanded in a DMEM/F12 medium and were incorporated in collagen Methods: Biomimetic Calcium Phosphate (BioCP), a novel bone-filling mate- I gels, which were placed underneath a PET membrane of cell culture inserts. rial, was made from 5-fold supersaturated calcium phosphate solution (CPS) This membrane was coated before with different ECM molecules. Elastin, fibro- at 37°C and pH 7.4 using biomimetic principles. Fluorescein-isothiocyanate nectin and collagen I were used. On the surface of the membrane a multilayered labelled bovine serum albumin (FITC-BSA) was incorporated into BioCP during epithelium with gingival keratinocytes was grown. The already well developed the preparation as a model protein. BioCP was characterized using scanning epithelium was then wounded and the wound closure was monitored daily. electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). results: In the scratch wound assay the speed of the keratinocyte migration The in-vitro degradation rate of BioCP was monitored by measuring released was investigated. It was shown that protein coatings of a surface have a signifi- calcium ions using atomic adsorption spectrometry. The rate and pattern as cant impact on migration speed. On a collagen I coated surface, for example, well as the in-vitro release kinetics of BioCP and incorporated proteins were the keratinocytes migrated faster compared to an uncoated surface. monitored. BioCP material was tested by mouse osteoblasts, compared to de- In the 3D organotypic epithelial model wounds were created after 7 days of proteinized bovine bone, using ALP activity and DNA assay. incubation at the air-liquid phase using a pipette tip. The photographic moni- results: BioCP showed an amorphous morphology and a ratio of calcium toring of the wounded epithelium that was grown on uncoated PET membranes and phosphorus at 1.48. The size of BioCP granules can be 0.3-2.0 mm. The showed that the wounds were partly closed after 5 days. BSA was successfully incorporated into BioCP with an incorporation rate of The histological characterization of the grown epithelia using HE-staining of 89.1±1.9% when the BSA concentration was 10 mg/L in the 5×CPS. The deg- paraffin sections showed that they were well stratified and keratinized. For the radation rate of BioCP was correlated with the protein release, and the later immune histological characterization keratin 1/10, involucrin and the prolif- showed a slower release kinetic. The BioCP material improved the ALP expres- eration marker Ki67 were used as marker proteins. The keratin 1/10 was ex- sion/DNA more than deproteinized bovine bone (P ‹ 0.05), when mouse osteo- pressed in the stratum spinosum and granulosum. Involucrin was expressed blasts were cultured on them separately after 7 days’ culture. from the stratum spinosum to the stratum corneum. Conclusions: Biodegradable BioCP bone filling materials are not only useful Conclusions: The wound assays presented here provide biological relevant for bone repair, but also can act as a drug delivery system. The flexibility of data supporting the assumption of a promising test system to evaluate bioma- BioCP in structure and its capacity of coordinately delivering bioactive agents terials and chemical compounds and their effect on gingival epithelial wound conferred on the novel bone filling material a promising application potential in healing. The test models can be analysed frequently and so the progress of healing voluminous bone defects with different etiologies. wound healing can be well monitored and documented. 310 i The use Of BMp in Maxillary Sinus lifting and 312 i Evaluation Of Nanoporous and Macroporous polymer Hydro- in Human Extraction Sockets: a Systematic review gels as a potential Barrier For Guided Bone regeneration (GBr)56
    • baSic reSearch, in Vitro StudieSdavid lescano (argentina), Edith I. Yslas, Maria A. Molina, Claudia Rivarola, Conclusions: This study showed the possibility of DPPSC as a potentially inter-Cesar Barbero, Viviana Rivarola esting candidate for bone tissue engineering.Objectives: 1. Synthesis of (poly(n-isopropylacrylamide-co-(2-acrylamido-2-methylpropane sulfonic acid)) (PNIPAm-co-2%AMPS). 314 i Osteoblastic and Osteoclastic differentiation On Sla2. Characterization of PNIPAm-co-2%AMPS using a scanning electron micros- and Hydrophilic Modified Sla Titanium Surfacescopy (SEM).3. Determination of permeability properties of PNIPAm-co-2%AMPS nano and yong-dae kwon (korea), Sung-Moon Bang, Ji-Yeon Yoo, Young-Joo Kim, Ho-Jinmacroporous hydrogels. Moon, Ji-Yong Kim4. Evaluation of biocompatibility of PNIPAm-co-2%AMPS nano and macropo-rous hydrogels using LM2 cell lines. Objectives: In terms of bone remodelling, osteoclastic activity is also worth5. Analysis of cell adhesion on membrane surfaces of PNIPAm-co-2%AMPS investigating besides that of osteoblasts on a titanium surface. This study wasnano and macroporous hydrogels. to evaluate the activities of both of osteoblastic and osteoclastic differentiationMethods: In order to prepare the nanoporous polymer, the hydrogel was dried on SLA and hydrophilic modified SLA surfaces.by heating the PNIPAm-co-2%AMPS and a polymer network without voids in Methods: Osteoblastic assays: Titanium (Ti) discs were obtained from Insti-its structure was obtained. Further swelling of this material in water increased tute Straumann, representing the following surfaces: smooth pre-treatmentthe network chain space in the polymer matrix by ~36 nm. (PT; as control), sandblasted/acid etched (SLA), and hydrophilic SLA (modSLA).To obtain the macropores, the polymer was prepared below the bulk freezing tem- MC3T3-E1 cells were cultivated on the respective substrates for osteoblasticperature of the reaction system (-18o C). During this process ice crystals acted as differentiation. To evaluate the osteoblastic differentiation, ALP assay was per-a template for the formation of the macro pores. To characterize the structure of formed and the Alizarin red S test was performed for the mineralization testthese materials, SEM studies were carried out at low vacuum and low field using after 1 week, 2 weeks and 3 weeks. For the molecular biological study, the RT-a LEO 1450VP SEM. The permeability of these hydrogels was determined by pas- PCR test was performed to investigate the expression of Runx2, osteopontinsive diffusion of toluidine blue and Höechst dye. Biocompatibility of these materi- (OPN) and osteocalcin (OCN).als was checked by following morphology and adhesion of LM2 cells cultured over Osteoclastic assays: Mouse derived bone marrow monocytes were cultivatedthe hydrogels. These experiments were performed using fluorescent microscopy. on the respective substrates for 7 days for differentiation of osteoclasts. ForToluidine blue and Höechst dyes were used as probes for labelling the cells. the osteoclastic differentiation, M-CSF and RANKL were included in the cultureresults: SEM studies show clear macroporous structure. The distribution of medium. We confirmed the constitution of osteoclast differentiation using themacropore size is very narrow with a mean value of about ~64 nm. The shape confocal laser microscope, TRAP activity and RT-PCR.and size of the macropores change after the gel is subjected to drying and rehy- results: In osteoblastic experiments, the SLA and modSLA surfaces signifi-dration. During drying the pores collapse and are then rehydrated into a differ- cantly increased the expression of Runx2, OPN and OCN mRNA compared withent shape. After the initial rearrangement, the pore morphology remains stable that of the control. The expression of Runx2 and OPN as early markers wasduring drying/wetting cycles. To calculate the size of the pores in nanoporous up-regulated the most in 2 weeks, but that of OCN as a late marker was up-hydrogels we used the theory of equilibrium swelling obtaining an average of 36 regulated the most in 3 weeks. The promotion of osteogenic differentiation isnm. The adhesion of cells to hydrogels was studied observing cell interactions demonstrated by increased Alizarin red S and ALP assay. In osteoclastic ex-with these substrates. Microscopic examination revealed that the cells adhered periments, the SLA and modSLA surfaces showed decreased attachment andto and grew onto the surface of material as well as inside its pores, showing differentiation of monocytes. Based on the findings of the confocal microscope,regular cell morphology. Fluorescence microscopy analysis showed that the monocytes were sparse and osteoclastic differentiation was rarely seen. Thecells adhered and normally grew onto the surface of material as well as inside results of TRAP activity and RT-PCR supported these results.its pores. This result shows that the hydrogels were non-cytotoxic. Conclusions: The SLA and modSLA surface enhanced osteogenic differentiationConclusions: We have evaluated both nano and macroporous hydrogels as of MC3T3-E1 cells more than the PT surface did. But the monocytes did not ad-a membrane barrier for GBR. We showed that both micro and macroporos- here to the SLA and modSLA surfaces and their differentiation was disturbed. Thisity allow exchange of water and small molecules. In addition the material is result may imply that differentiation of monocytes is prevented on these surfaces.biocompatible for lm2 cells. These studies demonstrated that the pnipamm- It may be concluded that the modSLA surface will promote the osteogenic ef-co-2%amps nano and macro porous hydrogels have a high potential as a bar- fect and prevent the bone resorption by avoiding osteoclastic differentiationrier membrane for GBR. Future experiments are necessary to evaluate the around the surface of an implant.behavior of hydrogels in vivo. 315 i Osteoclastic differentiation Of Mouse derived Monocytes On313 i The Enhancement Of Osteogenesis in 3d By using a Magnesium-incorporated Submicro-porous Titanium Oxide SurfaceSub-Mesenchymal Stem Cell population From The dental pulp yong-dae kwon (korea), Sung-Moon Bang, Young-Joo Kim, Ji-Yong Kim, Ji-YeonJordi Caballe (Spain), Carlos Gil, Marc Fabregat, Dani Garcia, Luis Giner, Maher Yoo, Ho-Jin MoonAlatari Objectives: The objective of this study is to demonstrate the effects of an Mg-Objectives: Large bone defects are a major clinical problem, because in up to incorporated submicro-porous Ti oxide surface on the osteoclastic differentia-40% of patients autologous bone grafts are not available. Bone bioengineering tion of mouse-derived monocytes.would be a good solution to this common problem. To improve the regenerative Methods: A titanium oxide surface incorporating magnesium ions (Mg) wascapacity of osteoblasts in 3D, we used a sub-mesenchymal stem cell popula- compared with an untreated titanium surface (PT) and tissue culture polysty-tion from the dental pulp DPPSC as a candidate for bone tissue engineering. rene (TCP) served as a control substitute. For the osteoclastic differentiation,Methods: In the present study, we evaluated the osteogenic capacity between M-CSF and RANKL were added to the culture medium. Mouse derived boneDPPSC and DPMSC isolated from the same donor (n=5) y cultivated in the same marrow monocytes were cultivated on respective substrates and differentiatedosteogenic medium in a 3D cell carrier glass scaffold. The differentiation was for 7 days. We confirmed the constitution of osteoclasts by the confocal laserevaluated by SEM analysis, the expression of bone markers like ALPH, osteo- scanning microscope, TRAP activity tests and RT-PCR.calcin, Coll I and osteonectin by q-RT-PCR. We also compared calcium deposi- results: Confocal laser microscope investigation showed the increased osteo-tion, the Alizarin staining test and ALP activity. clastic differentiation capacity of Mg-incorporated surfaces compared to thatresults: Bone was formed by DPPSC in perfect continuity with the trabecular of PT and TCP. Both PT and Mg-incorporated Ti oxide surfaces showed typicalhost bone structure and demonstrated the high interconnectivity of the re- actin rings of osteoclastic differentiation. It was further demonstrated by genestored bone network. A significant difference was observed in the expression expression data and increased TRAP activity assay. The mRNA synthesis ofof bone markers, Calcium deposition and ALP activity during the osteogenic various osteoclast specific genes (TRAP, c-fos, NMP9, OSCAR) was measureddifferentiation used DPPSC more than DPMSC. by means of reverse transcription polymerase chain reaction (RT-PCR). 57
    • Conclusions: These results support the contention that Mg-incorporated sub- sition (Cerasorb M) and the hydroxyapatite composition. However, in the con- micro-porous Ti oxide surface may improve the differentiation of osteoclasts. struct with the Fortoss VitalTM component, the osteogenic differentiation was established via determination of the ALP-concentration and analysis of gene expression, but not via immunohistochemical staining analysis. 316 i Osteoporosis in The Maxillofacial area – a Study in Sheep Conclusions: The study results demonstrate that mesenchymal stromal cells did not lose potential for osteoblastic differentiation within the three dimen- pit Jacob Voss (Germany), Egle Veigel, Rainer Schmelzeisen sional constructs. However the osteogenesis occurs after a time lag of seven days. In the three dimensional constructs analyzed, results indicated that when Objectives: Osteoporosis (OP) is characterized by low bone mass and microar- considering the choice of mineral component of the composition, equivalent chitectural deterioration of bone tissue. The presence of this disease in the cra- efficacy was found with hydroxyapatite and ß-tricalcium phosphate as a source niomaxillofacial (CMF) area remains unclear. The available small animal mod- of calcium. els show deficiencies. The aim of the present study was to assess bone changes occurring in the mandible in a sheep model of generalized osteoporosis. Methods: Bone loss was induced in ten Merino sheep by ovariectomy (OVX), 318 i Modified Silk Membranes: weekly intramuscular administration of glucocorticoids (GC) for 6 months and an innovative Scaffol in Guided-Tissue regeneration a calcium-reduced diet. The intervention group was divided in two subgroups: 5 animals were killed after 3 months and 5 animals after 6 months. The objec- ralf Smeets (Germany), Daniel Rothamel, Jörg Handschel, Marco Blessmann, tive of this approach was to assess bone recovery for a longer period of time Max Heiland, Andreas Kolk after steroid suspension, with a view to allowing implantation in this animal model without the negative side-effects of steroid medication. Five untreated Objectives: Guided tissue regeneration (GTR) is well established for different animals served as controls. Bone mineral density (BMD) was assessed by types of barrier membranes. Here we report a novel ST-silk membrane which dual-energy X-ray absorptiometry at the lumbar spine at baseline and after 1, offers advantages compared to established animal derived collagen mem- 3, 6, 9, and 12 months. Lumbar and mandibular bone biopsies were obtained branes. ST-silk membranes can be surface functionalised, are free from any and analyzed with micro-CT. The studied variables were the bone volume to potentially infective pathogens and have excellent mechanical properties. In tissue volume ratio (BV/TV), trabecular thickness (Tb. Th.), trabecular number this study we achieved functionalisation of the ST-silk membranes with hy- (Tb. N.) and trabecular separation (Tb. Sp.). The cortical thickness was also droxyapatite (HA) and the proliferative effects of the membranes were evaluat- measured. ed on osteoprogenitor cells e.g. rat mesenchymal stromal cells (MSC) in vitro. results: Lumbar BMD decreased progressively in the intervention group and Methods: First, native ST-silk membranes were tested regarding their effects was most significantly low after 6 months (p ‹ 0.001). Lumbar trabecular bone on proliferation rates of L929 fibroblasts and dysplastic oral keratinocytes showed a significant decrease in BV/TV (p ‹ 0.05) in the inducted group. Signifi- (DOK cell line). Possible cytotoxic effects were analysed by monitoring LDH ac- cant changes were also found in the mandibles for BV/TV (p ‹ 0.05). Regional tivity. Thereafter, HA-functionalized ST-silk membranes were seeded with rat variations were found for other parameters in the mandible. The cortical width MSCs and the effects on osteogenic differentiation were evaluated for 7 days. was substantially reduced in the intervention group (p ‹ 0.001). Additionally the membranes were scanned via different imaging modalities: Conclusions: The OVX rat has become the standard small animal model for OP. Reflection electron microscopy (REM), µ-CT and digital microscopy VHX-600. The lack of cortical remodelling in rodents and their reduced body mass are results: ST-silk membranes demonstrated good biocompatibility without neg- major limitations while testing implants. A big animal model for OP is neces- ative effect in terms of vitality/proliferation of L929 and DOK cells over 22 days. sary in such cases. Bone loss can be induced on sheep by various methods. The membranes showed osteoinductive effects (increase in alkaline phospha- We showed that bone loss is achievable in a short period of time and that the tase activity) on rat MSCs after 7 days. Biomechanical tests of the membranes changes have a generalized nature. This sheep model meets the criteria for result in elongation values of up to 170% with collagen compared to 440% with further investigation in the CMF area. silk and tear-off of 8.5MPa using collagen compared to 11.6 MPa for silk. Conclusions: Functionalisation of ST-silk membranes with hydroxyapatite seems to have an osteoinductive effect on MSCs in vitro with biocompatibility and 317 i a New 3d-Construct For Bone augmentation in implantology mechanical stability superior to membranes based on collagen. These innovative devices open promising avenues for any application in guided tissue regenera- ralf Smeets (Germany), Jörg Handschel, Daniel Rothamel, Marco Blessmann, tion and as scaffold material in tissue engineering for dental applications. Max Heiland, Andreas Kolk Objectives: Compromised bony conditions or bone volume deficiency are com- monly encountered problems in dental implantology. The objective of this study was the basic research for the development of a three dimensional osteoregen- erative scaffold, analogous to bone, consisting of a textile component combined with a bone substitute material (BSM) for midfacial surgery. The influence of BaSiC rESEarCH, prECliNiCal STudiES this bone regenerative construct was analyzed with respect to the proliferation and osteogenic differentiation of mesenchymal stromal cells (MSC). Methods: MSCs were cultivated for 21 days in three dimensional constructs, made with a number of commercially available BSMs (Cerasorb® M, Ostim®, 401 i Effect Of platelet-rich plasma On Bone regeneration in Fortoss VitalTM, Tricos®, Nanobone®, BioOss®, OsteoBiol®mp3), in combination Combination With Beta-Tricalcium phosphate in Calvarial defects with a fibrin glue and a textile component of poly-L-lactic acid( PLLA). Prolifera- in Ovariectomized rabbits. tion, cytotoxicity, alkaline phosphatase (ALP) activity and gene expression were tested for each material composition over the whole period of the study. Fur- Jae-Jun ryu (korea), Il-Yeon Kim thermore, osteogenic marker proteins were immunohistochemically analyzed. results: Via determination of ALP, gene expression analysis and immunhis- Objectives: The aim of this study was to assess the effectiveness of Platelet- tochemical staining, a delay of differentiation was established within all of the Rich Plasma (PRP) on bone regeneration in combination with beta-tricalcium three dimensional construct compositions. Furthermore, the results indicated phosphate (TCP) alloplast in calvarial defects in ovariectomized rabbits. that the choice of BSM had no bearing on the osteogenesis of the MSC. BioOss Methods: Fourteen Zealand white rabbits were ovariectomized to induce ex- induced an osteogenic differentiation. Using the BSMs Ostim, Cerasorb M and perimental osteoporosis. After 6 weeks, 2 bilateral defects measuring 10mm Fortoss VitalTM, osteogenic differentiation was detected within two of three in diameter were created in the parietal bones. In the experimental group, one assays. The highest ALP-concentration was detected in three dimensional con- defect was filled with beta-TCP combined with PRP and the other was filled struct containing Ostim, but no genes of bone markers could be detected by with bovine bone mineral combined with PRP (PRP group). In the control group, RT-PCR. A similar outcome was found with the ß-tricalcium phosphate compo- each defect was filled with beta-TCP and bovine bone mineral only (Non-PRP58
    • baSic reSearch, Preclinical StudieSgroup). Dual energy X-ray absorptiometry was obtained at baseline and 6 Methods: We compared the histological findings of control (no graft), Bio Oss,weeks after ovariectomy. After 4 weeks, the animals were sacrificed and cal- MBCP (HA 60%, beta-TCP 40%), Polybone (polyphosphate containing calciumvarial sections were prepared. Bone mass (BV/TV) was measured by micro-CT. phosphate) in the extraction sockets. The mandibular premolar teeth of 4 bea-Histological and histomorphometic analyses were carried out on samples. The gle dogs were extracted for bone grafting. All alveolar extraction sockets weregathered data were statistically analysed (ANOVA, t-test, p ‹ 0.05). thoroughly debrided with a surgical curette to remove the periodontal liga-results: Bone mineral density (BMD) decreased significantly at 6 weeks after ment. The graft materials were filled into the extraction sockets. The animalsovariectomy (p ‹ 0.05). The quantitative micro-CT analysis demonstrated a sta- were sacrificed 90 days after implantation. Both treated and control mandibu-tistically significant difference in new bone formation between the PRP and non- lar sites were histologically evaluated with light microscopy.PRP group. BV/TV was higher in the PRP group (P ‹ 0.05). The histological ex- results: Histological observation at 90 days revealed that the control and ex-amination showed new bone formation around the bone substitute particles in perimental sites had healed uneventfully without any adverse tissue reaction.all groups. In the histomorphometric analysis, the PRP group showed a greater Regenerated new bone formation ratio was 34.5% for control, 22.1% for Bioarea of new bone formation than the non-PRP group (p ‹ 0.05). beta-TCP par- Oss, 28.4% for MBCP and 23.8% for Polybone. There was no statistical differ-ticles were more rapidly resorbed than bovine bone particles. Therefore areas ence between graft materials.of remaining particles were lower in the groups grafted with beta-TCP particles. Conclusions: These results suggest that Bio Oss, MBCP and Polybone areConclusions: The osteoconductivity of the beta-TCP alloplast was similar to that promising bone substituting materials to promote normal tissue healing andof bovine bone mineral in ovariectomized rabbits. The PRP group showed higher new bone formation.values than the non-PRP group in micro-CT and histomorphometrc analysisin terms of new bone formation. The PRP may have beneficial effects on boneregeneration when added to osteoconductive materials in osteoporotic hosts. 404 i adipose-derived Stem Cells (adSc) as a Tool For The in Vitro reconstruction Of Safety Vascularized Bone Grafts402 i Histological Evaluation Of autologous periodontal ligament Barbara zavan (italy), Eriberto Bressan, Stefano Sivolella, Gian Antonio Favero,Cells With Enamel Matrix derivatives in artificial Class Furcation Vittorio Faverodefects. an Experimental Study in Monkeys Objectives: In the field of tissue engineering and regenerative medicine, adultWeidong zhu (China), Jianxia Hou, Kaining Liu, Huanxin Meng, Xiaolin Tang stem cells are increasingly recognized as an important tool for in vitro re- constructed tissue-engineered grafts. In the world of cell therapies, mesen-Objectives: To evaluate whether autologous periodontal ligament cells chymal stem cells from bone marrow or adipose tissue are undoubtedly the(PDLCs) combined with or without enamel matrix derivatives (EMD) can pro- most promising progenitors for tissue engineering applications. In this setting,mote periodontal tissue regeneration (including alveolar bone, cementum and adipose-derived stem cells (ADSCs) are generally similar to those derived fromperiodontal ligament) in artificial class furcation involvement (FI) in monkeys. bone marrow and are most conveniently extracted from tissue removed duringMethods: The autogenous PDLCs obtained from the extracted first pre-molar an elective cosmetic liposuction procedure showing moreover a great potentialwere cultured in vitro with Bio-oss Collagen. Eighteen chronically infected in term of endothelisation. The aim of the present work was to investigate theclass FI defects were surgically created at the mandibular molars and second use of ADSCs as tools for improving the in vitro and in vivo reconstruction of apremolars of three adult male Macaca fascicularis monkeys. Six furcation de- safety vascularized bone graft.fects with different therapies in each monkey were included: PDLCs/Bio-oss Methods: The aim of the present study was to investigate the use of ADSCsCollagen + EMD (PBE), Bio-oss Collagen + EMD (BE), PDLCs/ Bio-oss Colla- as tools for improving the in vitro and in vivo reconstruction of a safety vascu-gen (PB) and Bio-oss Collagen (B) at first and second molars, EMD and the larized bone graft. Human ADSCs obtained from abdominoplastic proceduresblank at second pre-molars, respectively. All of the furcation defects (including were first grown in monolayer culture, and after 14 days, were loaded into abuccal and lingual sides) were covered with collagen membranes before flap bovine-derived hydroxyapatite clinical-grade scaffold and tested for prolifera-close. The monkeys were euthanized 6 months after implantation. Healing of tion, cellular distribution and for osteogenic and vasculogenic gene expression.the periodontal defects was evaluated histomorphometrically with hematoxylin The safety of the cultures was investigated using the CGH array for 3D cultures.and eosin stain and the regenerated periodontal tissues were expressed as ADSC adhesion, distribution, proliferation and gene expression demonstratedpercentages. not only full commitment on to osteogenic and vasculogenic lineage but alsoresults: The dimension of defect between two roots and the buccal-lingual that the endothelisation significantly improves osteo-commitment. In the end,distance in the second premolar were smaller than that in the molars. The for in vitro cultures, genetic analyses confirmed the safety of the long-termnew alveolar bone, new periodontal ligament and new cementum regenerated culture of ADSCs in 3D scaffolds. For in vivo calvarial defect regeneration, HAin the defects of the second premolars (78%–84%, 69%–82% and 86%–89%, bone grafts embedded with ADSCs were implanted for 3 weeks.respectively) were significantly greater than those in the defects of the mo- results: The histological and gene expression results demonstrated in this caselar groups (42%–51%, 40%–45% and 46%–73%, respectively). The new tissues also that the presence of ADSCs shows the highest expression of osteogenicin the defects of molars were approximately the same, except that there was and vasculogenic markers, compared with the samples with no stem cells.much more new cementum in the PBE (73%) group than in the other groups Conclusions: This study demonstrated that the presence of endothelial cells(46%–50%). There was less regeneration in the defects where gingival reces- signficantly improves the osteo-commitment of adult stem cells in vivo andsion occurred and did not cover the entrance of defects; epithelial proliferation in vitro.and connective tissue infiltrated by inflammatory cells instead of new tissueregeneration were observed in such defects.Conclusions: Class FI could not predictably be resolved even with the combina- 405 i deproteinized bovine bone mineral in marginal defectstion of PDLCs and EMD. The sizes of FI (including depth height, buccal-lingual at implants installed immediately into extraction sockets –and mesial-distal dimension), coverage of gingival flap and local inflammation an experimental study in dogswould influence the treatment outcome. Marco Caneva (italy), Daniele Botticelli, Gabriele Baffone, Idelmo Rangel, Niklaus P. Lang403 i Histological and Histomorphometrical Study OfExtraction Socket Grafted With deproteinized Bovine Bone Objectives: The aim of the present experiment was to evaluate the influence ofMineral and Calcium phosphate Materials DBBM and collagen membrane on alveolar ridge preservation and on the os- seointegration of implants placed into alveolar sockets immediately after toothSeungbeom kye (korea), Seungyoon Shin, Seungmin Yang, Sangik Park extraction in a dog model. Methods: In the mandibular premolar region, implants were installed immedi-Objectives: The purpose of this study was to evaluate the histological result of ately into the extraction sockets of 6 Labrador dogs. DBBM and collagen mem-bone substituting materials on extraction sockets. branes were placed at test sites, while the control sites received no augmenta- 59
    • tion materials. The implants were intended to heal in a transmucosal mode. the osteoblast cultures. The right femurs and tibias of the mice were prepared After 4 months of healing, the animals were sacrificed and ground sections for histological samples. The samples were stained with hematoxylin-eosin were obtained for histomorphometric evaluation. to analyse endosteum and periosteum and with tartrate resistant acid phos- results: After 4 months of healing, all the implants were integrated (n=6). Both phatase (TRACP) staining to analyse osteoclasts. Microcomputed tomography at the test and the control sites, bone resorption occurred. The greatest coro- (µCT) was used to analyse long bone morphology. Results were analysed with nal bone-to-implant contact was at the buccal aspect 2.8 ± 1.3 mm and 2.0 ± SPSS software with univariate analysis of variance taking into account the dif- 1.1 mm, at the control and test sites respectively. This distance was statistically ferent ages of the mice. significant (p ‹ 0.05). results: Wnt11 was expressed in osteoblasts on culture days 3, 7, 9 and 14. Conclusions: The present study demonstrated that the use of deproteinized The osteoblast differentiation and mineralization assay revealed that the Wnt11 bovine bone mineral (DBBM) and a collagen membrane at implants placed into deficiency retarded osteoblast maturation. As indicated by the preliminary re- sockets immediately after tooth extraction generate a higher level of bone-to- sults, the cancellous bone volume was different in mice at different age but did implant contact compared to the control site. The use of DBBM and a collagen not differ between knockouts and wild types. This non-significance may also be membrane, however, did not prevent the resorption of the buccal bone crest. affected by the small number of mice. Conclusions: Wnt11 deficiency seems to delay osteoblast differentiation and mineralization but the extent of this inhibitory effect requires further investiga- 406 i Bone regeneration at implants placed into Extraction tion. Growth factors regulate bone metabolism by complex routes and Wnt11 Sockets Of Maxillary incisors in dogs may be one piece in that puzzle. Wnt11 enhances osteoblast maturation to- gether with BMP2 and R-spondin 2 (Friedman et al. 2009). The influence of this de Santis Enzo (italy), Daniele Botticelli, Fabio Pantani, Priscilla Pereira Flavia, pathway may still be offset to some extent by all the other factors involved in Marco Beolchini, Niklaus P. Lang the bone forming process. Objectives: To compare the influence of autologous or deproteinized bovine bone mineral as grafting material on the healing of buccal dehiscence defects 408 i Clinical and Histological assessments Of Equimatrix at implants installed immediately into the maxillary second incisor extraction For purified recombinant Human platelet-derived Growth socket in dogs. Factor-BB in a periodontal defect Methods: In the maxillary second incisor sockets of 12 Labrador dogs, im- plants were installed immediately following tooth extraction. A standardized david kim (uSa), Soo-Woo Kim, Peter Schupbach, Marc Nevins buccal defect was created and autologous bone particles or deproteinized bovine bone mineral were used to fill the defects. A collagen membrane was Objectives: Growth factors are natural biological molecules that mediate and placed to cover the graft material, and the flaps were sutured to fully submerge regulate key cellular events such as cell proliferation, chemotaxis, differentia- the experimental areas. Six animals were sacrificed after 2 months and 6 after tion and matrix synthesis by binding to specific cell-surface receptors. Purified 4 months of healing. Ground sections were obtained for histological evaluation. recombinant human PDGF-BB (rhPDGF-BB) along with various matrices un- results: After 2 months of healing, all implants were osseointegrated. All buc- derwent a series of rigorous and extensive preclinical and clinical investigations cal dehiscence defects were completely filled after 2 months irrespective of the to test their safety and efficacy in periodontal regeneration. Despite the advanc- augmentation material (autologous bone or BioOss®) applied. Bone-to-implant es in periodontal regeneration brought about by the rhPDGF-BB, the quest for contact on the denuded implant surfaces was within a normal range of 30-40%. alternative matrices is rationalized since the clinical effectiveness of rhPDGF- However, the newly formed tissue at 2 months was partially resorbed (› 50% of BB is dependent upon the delivery system’s ability to bind and release a thera- the area measurements) after 4 months. peutic dose of rhPDGF-BB at the strategic time. The objective of our study was Conclusions: Applying either autologous bone or deproteinized bovine bone to evaluate the safety and efficacy of a new matrix (Equine particulate graft, mineral to dehiscences at implants installed immediately into extraction sock- Equimatrix) in combination with rhPDGF-BB for periodontal regeneration. ets resulted in a high degree of regeneration of the defects with satisfactory Methods: Two-walled box type intrabony defects were surgically created on the bone-to-implant contact on the denuded implant surface. proximal and buccal side of the mandibular 2nd premolars and 1st molars in 6 healthy female hounds five weeks after the extraction of their mandibular 3rd and 4th premolars. A reference notch was made on the exposed roots with an inverted 407 i Wnt11 Signalling May Control Bone remodelling cone burr at the base of the defects. Prior to grafting, Equimatrix was thoroughly saturated with 0.3mg/mL rhPDGF-BB for a minimum of 10 minutes to allow for riina rytivaara (Finland), Irina Nagy, Jorma Määttä, Hanna Kokkonen, Seppo absorption of the PDGF molecule to the surface of the graft matrix. The defects Vainio, Juha Tuukkanen were then filled to the level of the alveolar crest, and the flaps were coapted for a tension-free primary wound closure. The negative control group did not receive Objectives: Wnt11 is one of the 19 Wnt signalling proteins that are involved any type of grafting. All animals were sacrificed 10 weeks after the periodon- in cell differentiation, apoptosis and migration during development and in tal regeneration procedures. Both histological and histomorphometric analyses adulthood. Wnt proteins are transported along canonical and non-canonical were performed to investigate the quantity of new bone and cementum formation. pathways. Canonical signalling stabilises beta-catenin and has been proven to results: During the postoperative period, healing was uneventful for all ani- increase bone mass and osteoblast differentiation (Day et al. Dev Cell 2005). mals. Light microscopic analysis for the negative control group noted that the There has been disagreement as to whether Wnt11 activates or deactivates alveolar bone defects were mainly filled with fibrous tissues with minimal canonical signalling (Tao et al. Cell 2005, Railo et al. Exp Cell Research 2008). amount of new bone formation compared to the bone substitute group. For Some research into the effects of Wnt proteins on bone has been done. Fried- the Equimatrix + rhPDGF-BB group, a remarkable evidence of newly formed man et al. overexpressed Wnt11 in MC3T3E1 pre-osteoblasts. They noticed that bone which surrounded the bone substitute materials was evident. The mean beta-catenin accumulation and bone morphogenetic protein (BMP) induced ex- new bone formation was 42.0 ± 13.3 % for the Equimatrix + rhPDGF-BB group pression of alkaline phosphatase and mineralization was promoted because while it was 19.8 ± 11.7 % for the negative control group. This difference was of overexpression of Wnt11 (Friedman et al. J Biol Chem 2008). Wnt11 also in- statistically significant (P ‹ 0.01). The periodontal ligament was maintained creased expression of other osteoblast-associated genes. Thus Wnt11 seems along the root surface with no evidence of root resorption or ankylosis. In to be an influential factor in osteoblast maturation. addition, a statistically significant amount of new cementum formation was Methods: C57B16 Wnt11 knockout mice and wild types aged between 2 months evident for the Equimatrix + rhPDGF-BB group (P = 0.001). The mean new to 10 months were used. In all, 13 wild type male mice and 9 knockouts were cementum length and % for the Equimatrix and rhPDGF-BB were 4.8 ± 1.3 compared and with females comparison was made between 15 wild type mice mm and 80.2 ± 19.1 %, while they were 1.7 ± 1.9 mm and 35.8 ± 27.4 % for the and 12 knockouts. Primary osteoblast cultures of 14 days in the presence of negative control group. Na-ß-glycerophosphate and vitamin C were prepared from the bone marrow Conclusions: Equimatrix and rhPDGF-BB demonstrated a statistically signifi- mesenchymal stem cells of WT and KO mice. RT-PCR indicated that Wnt11 cant amount of new cementum length and a greater amount of new bone area is expressed in osteoblasts. Total RNA was isolated on day 3, 7, 9 and 14 from compared to the control group. The potent wound-healing effects of rhPDGF-60
    • baSic reSearch, Preclinical StudieSBB in combination with Equimatrix provided an innovative method for local de- Methods: Five adult New Zealand rabbits (Oryctolagus cuniculus) were usedlivery of highly potent growth modulators to maximize regenerative potential. in this study. Three were sacrificed after 30 days. Each animal provided 2 sites on its skull. The sites for stabilization of the hemispheres were made with a trephine 9 mm in diameter and 1 mm in length. 10 perforations were made in409 i dental Trauma Management awareness among primary the circles thus formed with a 699 conical burr in order to stimulate bleeding.Schools Teachers in ajman, united arab Emirates. The hemispheres were filled with nanocrystalline Hydroxiapatite NanoBone® (Artoss GmbH, Germany). After sacrifice, sections were obtained and stainedraghad Hashim (united arab Emirates) using the Hematoxilin/Eosin (HE) and Masson’s trichrome (MT) methods. results: Intense cell proliferation along with extensive formation of collagenObjectives: To assess, by means of a self-administered structured question- and bone matrix could be observed in the samples after 30 days. This largenaire, the level of knowledge of primary schools teachers in Ajman with re- number of cells was still present after 30 days. This demonstrates the excel-gards to the immediate emergency management of dental trauma. lent osteoconductive properties of the material. The sections showing goodMethods: The questionnaire was sent to teachers in randomly selected pri- results in terms of bone quality and quantity, amount of new bone and numbermary schools in Ajman. A total of 161 teachers responded (response rate of cells involved in the bone neoformation process.84.4%). The questionnaire surveyed teachers’ background and knowledge and Conclusions:The results of this material at 30 days indicate that grafting withmanagement of tooth fracture and avulsion, and also investigated teachers’ NanoBone® promotes new bone formation, providing the grafted area with aattitudes and self-assessed knowledge. greater amount of cellular activity. This would theoretically allow successfulresults: Ninety-one percent of the teachers were females, 51.6% in their thir- installation of implants in an adequate bone bed. Additional studies would beties; 61.5% had university qualifications. Fifty teachers had received formal first necessary to confirm this statement.aid training, only thirteen of them recalled that they had received training inthe management of dental trauma. Concerning the management of tooth frac-ture, 138 respondents (85.8%) gave the appropriate management for fractured 412 i Combined Surgical Therapy Of advancedtooth. Over 121 (75%) of the respondents indicated that professional assistance ligature-induced peri-implantitis defects. part i.should be urgently sought if a permanent tooth had been avulsed, but they had Cone-beam Computed Tomographic analysis.little knowledge of the correct media for transporting the avulsed tooth. Mostteachers were unsatisfied with their level of knowledge of dental trauma and Mihatovic ilja (Germany), Narja Sahm, Vladimir Golubovic, Jürgen Becker,the majority were interested in having further education on the topic. Frank SchwarzConclusions: The findings revealed that the level of knowledge of managementof dental trauma (especially tooth avulsion) among school teachers in Ajman Objectives: To evaluate the impact of rhBMP-2 on the radiographic bone gainis inadequate and education campaigns are necessary to improve their emer- (RBG) (i.e. cone-beam computed tomography, 90 kV, 3.1 mA, voxel size 0.2 mm)gency management of dental injuries. after surgical therapy of ligature-induced peri-implantitis in dogs employing a particulated bone filler (NBM) (intrabony - i) combined with either an equine bone block (EB) or implantoplasty (P) (supracrestal - s).410 i The impact Of Osteoporosis and diabetes Methods: Defect sites were randomly allocated in a split-mouth design to theOn Graft Consolidation in rat Calvaria following groups: (1) NBM (i)/ EB (s) (i.e. EB and EB+rhBMP-2), or (2) NBM (i)/ P (s) (i.e. P and P+rhBMP-2). The sites were left to heal in a submerged posi-alexander Fügl (austria), Stefan Tangl, Claudia Keibl, Georg Watzek, Heinz tion for 12 weeks.Redl, Reinhard Gruber results: Mean RBG values were significantly lowest in the P group (1.0±1.0 mm), when compared either with the EB (1.7±0.7 mm), EB+rhBMP-2 (1.8±1.6Objectives: Implant placement frequently depends on bone augmentation. mm), or P+rhBMP-2 (2.0±0.8 mm) groups. The differences between the EB,However, the impact of systemic metabolic diseases on the consolidation of EB+rhBMP-2, and P+rhBMP-2 groups were statistically non-significant. Meanbone substitutes remains poorly understood. Our goal is to study the impact of RBG values were equally distributed between mesial/distal and vestibular/oralosteoporosis and diabetes on graft consolidation in rat calvaria. aspects in all groups.Methods: We determined a rat model in which methacrylate hemispheres filled Conclusions: It was concluded that i) rhBMP-2 soak-loaded NBM may havewith deproteinized bovine bone mineral were fixed on the calvaria. One group the potential to improve RBG at i-components, and ii) EB with or without rh-received streptozotocin (STZ) to induce diabetes mellitus and rats treated with BMP-2 did not seem to be associated with a complete radiographic bone fill atan equivalent solution served as controls. Another group of animals underwent s-components.ovariectomy (OVX), causing osteoporosis. The control animals remained un-treated. Specimens were assessed by histomorphometry and µCT.results: Graft consolidation was similar between the two groups. The rate 413 i Transforming Growth Factor-ß1 accelerates resorptionof new bone formation after 4 weeks was 0.61±0.53% in the STZ group and Of a Calcium Carbonate Biomaterial in periodontal defects0.69±0.91% in the control group. After 8 weeks, the rates of new bone formationwere 4.98±3.16% in the OVX group and 2.35±1.30% in the control group. The vol- ki-Tae koo (korea), Ulf Wikesjo, Young Ku, Yong-Moo Lee, Yang-Jo Seol,ume occupied by the bone substitute was not affected by STZ or OVX treatment. In-Chul RhyuThe low amount of newly formed bone could not be quantified by µCT.Conclusions: We conclude that neither STZ nor OVX altered the early phase of Objectives: It has been suggested that several growth or differentiation factorsgraft consolidation. Our findings are limited by the weak osteogenic potential accelerate the degradation of biomaterials used as carriers. The objective ofof the rat calvaria in this augmentation model. this study was to evaluate the possible action of rhTGF-ß1 on the biodegrada- tion of the calcium carbonate carrier and its effect on periodontal regeneration with a special focus on bone.411 i Histological Evaluation Of The quantite Of Bone Formation Methods: The rhTGF-ß1 in a putty-formulated particulate calcium carbonate carrier was implanted into critical-size, supra-alveolar periodontal defectsSergio Gehrke (Brazil) under conditions for GTR in five beagle dogs. Using a split-mouth design, con- tralateral, supra-alveolar periodontal defects were implanted with rhTGF-ß1inObjectives: The aim of the present study was to assess the influence of a nano- a carrier or with carrier alone (control). The animals were euthanized at weekcrystalline hydroxyapatite in titanium hemispheres in the skull of rabbits. The 4 post-surgery and block biopsies of the defect sites were collected for histo-bone growth was assessed by analyzing histological sections taken 30 days logical and histometric analysis. The following parameters were recorded forafter surgery. The proposition was to evaluate the potential of bone stimulation buccal and lingual tooth surfaces for each section: defect height, defect area,and promotion of the nanocrystaline Hydroxiapatite NanoBone® in titanium regenerated bone height, regenerated bone area, residual carrier area and re-hemispheres in contact only with blood from the bone tissue. sidual carrier density. Measurements at tooth level and generalized estimat- 61
    • ing equations were used to assess the impact of different factors on carrier Victor palarie (Moldova), Peer W. Kämmerer, Olga Tagadiuc, Viorel Nacu, Bilal resorption. Wald tests were used for multiple comparisons, and the level of Al Nawas significance was set at 5%. results: The rhTGF-ß1 and control groups did not differ significantly with re- Objectives: This experimental project was designed to evaluate differences in gard to defect characteristics (defect height, device height, and wound area). the sequential biochemical bone healing events that occur during the initial There were also no statistically significant differences in bone formation (height stages of guided bone regeneration (GBR) of chronic lateral ridge defects in and area) among the treatments. On the other hand, total residual carrier was rabbits with deproteinized bovine bone (Bio Oss®, GeistlichPharma AG), cov- significantly smaller in sites that received rhTGF-ß1 compared to that in the ered and non-covered with collagen membrane (Bio-Gides®, GeistlichPharma control (P = 0.04). Similarly, carrier density was considerably smaller in the AG). The outcomes of bone regeneration were measured by the activities of rhTGF-ß1 group; this difference did not reach statistical significance (P = 0.06). total and bone acid phosphatase and alkaline phosphatase in peripheral blood. This observation may indicate that rhTGF-ß1 increased the resorption rate of Methods: Eight weeks after formation of a defect in the right lateral mandible the putty-formulated particulate calcium carbonate carrier, but this effect did of six rabbits, the bone grafting procedure was carried out. In three animals not influence bone formation or regeneration of the periodontal attachment. A (group +), GBR with Bio Oss® particles and collagen membrane was applied. stratified analysis for wound area showed that carrier density and residual car- In three animals, only the bone substitute was used (group -). The peripheral rier area were significantly smaller for the rhTGF-ß 1 group in smaller wound blood was collected before surgery, 1, 24 and 72 hours, 7 days, 2 weeks and 3 areas (P ‹ 0.05). No significant differences were observed for these parameters weeks after surgery. Total acid phosphatase (TAcPh), bone acid phosphatase in larger wound areas (p › 0.05). No significant differences were observed be- (BAcPH), total alkaline phosphatase (TAlPh) and bone alkaline phosphatase tween experimental groups regarding new bone height and area irrespective (BAlPh) activities were determined in the peripheral blood, using standard kits of wound area (P › 0.05). In the multivariable model, residual carrier area was (Elitech, France). significantly smaller for the rhTGF-ß1 group, and this difference remained sig- results: Before surgery, no differences were detected between the two groups. nificant even after adjusting for wound and bone area. One hour after surgery, all parameters Conclusions: Within the limitations of the study, it may be concluded that rhT- were significantly higher in group + (TAcPh p=0.001, BAcPh p=0.003, TAlPh GF-ß1 accelerates biodegradation of a particulate calcium carbonate biomate- p=0.021, BAlPh p=0.006). 24 hours after surgery, only TAlPh activity was signifi- rial, indicating a biological activity of the rhTGF-b1 formulation apparently not cantly higher in group + (p=0.035). After 72 hours, all parameters were seen to be encompassing enhanced or accelerated periodontal regeneration. significantly higher in group + (TAcPh p ‹ 0.001, BAcPhp ‹ 0.001, TAlPh p=0.013, BAlPh p=0.024), whereas after 7 days no differences could be seen. After two weeks, TAcPh (p=0.003), BAcPh (p=0.003) and BAlPh (p=0.007) were higher in 414 i in Vivo Comparison Of Carbonated Hydroxyapatite group -. A significant difference in favour of group - could also be detected after Synthetic and xenogenic Scaffolds For Bone Tissue Engineering 3 weeks (TAcPH p=0.002, BAcPH p=0.001, TAlPH p=0.001, BAlPh p=0.008). Conclusions: Higher levels of enzyme activity indicate more intense bone re- alex Gurin (russia), Vladimir Komlev, Inna Fadeeva modelling. GBR with bone substitute particles and collagen membrane showed a desirable earlier remodelling activity. Objectives: Synthetic calcium phosphate biomaterials have been widely used in bone tissue applications and are of considerable interest as scaffold materials due to properties of osteoconduction, resorbability and in some cases osteoin- 416 i The influence Of alendronate On Osseointegration duction. This study is devoted to in vivo evaluation of carbonated hydroxyapatite Of Nanotreated dental implants in New zealand rabbits synthetic scaffolds (CHA) for potential use in bone tissue engineering in compar- ison with bovine bone derived (xenogenic) carbonated hydroxyapatite (Bio-Oss). Efstathia Tsetsenekou (Greece), Demos Kalyvas, Triantafillos Papadopoulos, Methods: Synthetic scaffolds with carbonate content of about 6 wt.% were Nikos Papaioannou, Georg Watzek, Stefan Tangl synthesized by solid-state reaction and divided into 2 groups: 1st group sur- face micropores ‹ 10 µm and inner cavities about 400 µm, 2nd group surface Objectives: Growing clinical demands for stronger and faster bone bonding to macropores about 150 µm and inner cavities 300 µm. For comparison Bio-Oss the implant have motivated the development of methods for enhancing osseo- spongiosa small granules (Geistlich, Switzerland) were used. integration. The application of bisphosphonates in order to optimise bone heal- X-ray diffraction, Fourier transform infrared spectroscopy (FTIR-4200, Shi- ing has recently attracted great interest. N-containing bisphosphonates, such madzu Co Ltd), evaluation of solubility in isotonic solution of 0.9% NaCl for 3 as alendronate, are the more potent drugs in this class. The aim of this study weeks, scanning electron microscopy (Hitachi S4800), histology evaluation (15 was to determine the effect of alendronate on the osseointegration of a well- days) in hole bone defect on Wistar rats, statistical morphometric analysis of documented nanotreated implant system in a rabbit femoral condyle model. bone matrix formation was performed by one-way analysis of variance (ANOVA) Methods: Thirty-two adult female New Zealand White rabbits received one with the MicrocalTM OriginTM Version 5.0 software package. implant (3,25mm in diameter and 10mm long) in their left femoral condyle, a results: X-ray diffraction results demonstrated that the broadening peaks of the week after they were ovariectomized. Half of them were saline-treated (con- CHA scaffolds are similar to the pattern of natural human bone, X-ray microanal- trol, group A) and the other half were alendronate treated (group B). Rabbits ysis demonstrated the presence of nitrogen in Bio-Oss granules. FTIR showed from both groups were euthanized after 6 and 12 weeks respectively. that the broad duplet bands at 1420, 1455 cm-1 and the band at 875 cm-1, which results: The specimens were evaluated histologically and histomorphometri- were characteristics of carbonate, were clearly observed in the CHA and Bio-Oss. cally. Upon histological evaluation, no obvious differences between the control The resorption rate in 0.9% NaOH was higher in CHA group 2. SEM showed dif- and treatment group were found. Implants showed good integration into the ferences in the structure of sintered CHA: scaffolds in the 1st group had surface bone tissue surrounding them. There were also no statistically significant dif- micropores ‹10 µm, on the cross section we observed inner cavities of about 200 ferences in bone to implant contact (BIC) and the amount of bone tissue (BV/ µm in diameter; scaffolds in the 2nd group had surface macropores of about 150 TV) in the immediate neighbourhood of the implant at both healing periods. µm and inner cavities of about 300 µm. Bio-Oss granules had surface micropores Conclusions: The systemic administration of alendronate was not found to af- of about 4–10 µm and large inner holes of about 500-800 µm. Histological evalua- fect the histological osseointegration of implants in animals with a hormonal tion showed active bone formation on synthetic CHA scaffolds in 2nd group. status resembling that of healthy post-menopausal women. Further research Conclusions: It is reasonable to use CHA scaffolds with surface macropores will be needed to investigate this approach. of about 150 µm as a bone substitute for filling bone defects. Porous scaffolds with micropores ‹10 µm have large inner cavities which could be used as a delivery carrier for stem cells and antibiotics. 417 i Histological Evaluation Of Bone regeneration in Surgically Created defects in rabbit Maxilla using Hydroxyapatite Bone Graft-prp Combination 415 i peripheral Blood as a Monitor Of Bone Healing Events in The rabbit Mandible after augmentation Caner atalay (Turkey), Vakur Olgaç, Elif Ergül, Ibrahim Akyazi, Duygu Yaman, With and Without Collagen Membrane Korkud Demirel62
    • baSic reSearch, Preclinical StudieSObjectives: New bone formation promoted by regenerative treatment methods is young-Sung kim (korea), Su-Hwan Kim, Won-Kyung Kim, Young-Kyoo Lee,still one of the important aims of periodontology and implantology. Guided bone Yong-Moo Leeregeneration is known as a predictable technique for bone augmentation. Allo-plastic graft materials have good osteoconductive properties, have no limitations Objectives: Since Boyne & James and Tatum, sinus augmentation has beenon availability and have no risk for disease transmission. Their composition closely used widely and showed clinically satisfactory result. However, regeneratedresembles the inorganic phase of bone. The degranulating granules of thrombo- bone in maxillary sinus was usually evaluated indirectly by X-ray images es-cytes release growth factors that affect wound healing. The aim of this study was to pecially in instances of simultaneous sinus augmentation and implant place-assess bone regeneration in surgically created defects in rabbit maxilla using al- ment. In this study, sinus augmentation with simultaneous implant placementloplastic bone substitute (hydroxyapatite)-platelet rich plasma (PRP) combination. in rabbit maxillary sinus was performed.Methods: 30 New Zealand White rabbits were divided into 2 groups of 15 The purpose of this study was to evaluate the effectiveness of autogenous graftanimals each. Bilateral 10mm ×5mm×3mm bone defects were created in the and bovine derived hydroxyapatite grafted simultaneously with implant place-maxilla of each animal. Group 1 had one defect filled only with HA-bone graft ment in maxillary sinus in space maintenance and new bone formation histo-and covered with resorbable collagen membrane, while the other defect was logically and histometrically.left empty and served as control. Group 2 had one defect filled with HA-bone Methods: 12 New Zealand white rabbits (aged 3 months, weight 3–3.5 Kg) weregraft and PRP, which was prepared from 10 ml autogeneous blood drawn from used for the this study. There were three experimental groups: control groupthe auricular artery and covered with resorbable collagen membrane, while (BC), in which sinus membrane was elevated and the sinus space filled withthe other defect was left empty. Five animals in each group were sacrificed at blood clot, autograft group (AB), in which the sinus space was filled with autog-day 15, 30 and 60. Bone sections were fixed in formalin, decalcified in sodium enous bone harvested from calvarium, and xenograft group (BHA), in which thecitrate and formic acid and placed in paraffin. Sections 5–7µm thick were pre- sinus space was filled with bovine derived hydroxyapatite. The grouping waspared, stained with haematoxylin and eosin and analyzed under light micro- the result of randomisation. A 1.4-mm in diameter, 6-mm long titanium bonescope by an experienced observer. Histological analysis was used to quantify screw was used as an implant analogue. Half of the rabbits were sacrificedthe amount of new bone within the defects. 4 weeks after surgery, and the others were sacrificed 8 weeks after surgery.results: The animals were maintained without adverse events. Bone fill was Histological observation of prepared undecalcified sections was performedassessed on a scale from 1 to 4: 1–30% (1), 31–60% (2), more than 60% (3), under a light microscope. For histometric analysis, the vertical height of mostcomplete (4). At day 15, 30 and 60 bone fill in Group 1 and 2 was greater than apical bone contact (VH), the amount of newly formed bone in the area of inter-in the control group, but there were no remarkable differences in bone fill be- est (NFB), the bone-to-implant contact (BIC) were measured using an imagetween Group 1 and Group 2. Remnants of bone graft were observed at day 15, analysis software.30 and 60 in defects filled with HA bone graft or HA-bone graft-PRP combina- results: BC group showed collapse of sinus membrane and small amount oftion. Kruskal Wallis, Wilcoxon sign-rank tests were used for statistical analysis. new bone formation limited around original sinus floor (OSF). In AB group, si-Conclusions: Wound healing within normal limits was observed in all groups. nus membrane was found above screw apex. Major new bone formation wasNo difference was observed between Group 1 and Group 2. Compared to HA, observed at 4 weeks, while remodeling of newly formed bone and adipose celltreatment with a combination of PRP with HA did not lead to significantly rich central region was observed at 8 weeks. BHA group showed retention ofgreater bone regeneration in surgically created bone defects. Adding PRP to sinus membrane above screw apex. New bone formation was limited betweenalloplastic bone grafts did not create any histological difference. However, PRP graft particles and the amount of new bone formation increased from 4 weeksfacilitates handling of the bone graft. The study was supported by Istanbul Uni- to 8 weeks. Bone-to-implant contact was observed in all groups.versity Department of Scientific Research Projects. The vertical height of most apical bone contact (VH) was greatest in BHA group followed by AB group and BC group (p=0.002). However, there were no sta- tistical significances in the amount of newly formed bone (NFB) and bone-418 i Sinus lift in Sheep With Mesenchymal Stem Cells to-implant contact (BIC) (p › 0.01). In comparisons of intra-group differences between 4 weeks and 8 weeks, there were no statistically significant pairs inSebastian Sauerbier (Germany), Michele Maglione, Toshiyuki Oshima, Samuel all groups (p › 0.01).Porfirio Xavier, Rainer Schmelzeisen, Ralf Gutwald Conclusions: From the results of this study, we can conclude as follows. Im- plant placement without augmenting the elevated sinus space is not appropri-Objectives: New reconstructive and less invasive methods have been searched ate in bone-deficient maxillary posterior region. Xenograft as well as autograftin order to optimize bone formation and osseointegration of dental implants can maintain the augmented sinus space. Autograft is superior to xenograftin maxillary sinus augmentation. The aim of the presented ovine split-mouth in the amount of new bone formation and maturation of newly formed bone.study was to compare autogenous bone, bovine bone mineral (BBM) alone and However, the clinical significance of the formation speed and maturation ofin combination with mesenchymal stem cells (MSCs) regarding their potential new bone should be investigated.in sinus augmentation.Methods: Bilateral sinus floor augmentations were performed in 12 adultsheep. BBM and MSCs were placed into the test side and only BBM in the 420 i The Effect Of Micro-Macroporous Biphasic Calciumcontra-lateral control side of 6 sheep. In the other 6 sheep BBM and MSCs phosphate and deproteinized Bovine Bone Mineral On Exophyticwere mixed and placed into one side and autogenous bone in the other side. Bone Formation in rabbit Calvaria3 animals of each group were sacrificed after 8 and 16 weeks. Augmentationsites were analysed by computed tomography, histology and histomorphom- Sung Guen kim (korea), Jin-cheol Kim, Yeek Herr, Jong-Hyuk Chung, Seung-Iletry. Statistically analyses were performed according to the mixed model by Shin, Young-Hyuk KwonPinero and Bates (function lme in package nlme under R).results: The differentiation assay revealed that multipotential mesenchymal stem Objectives: The purpose of the present study was to evaluate the osteocon-cells had been transplanted. The initial volumes of both sides were similar and did ductive effect of micro-macroporous biphasic calcium phosphate (MBCPTM,not change significantly with time. A tight connection between the particles of BBM MBCP) and deproteinized bovine bone mineral (Bio-Oss®, DBB) on exophyticand the new bone was observed histologically. Bone formation was significantly vertical bone formation in guided bone regeneration using titanium reinforced(p=0.027) faster by 49 % in the test sides and comparable to autogenous bone. e-PTFE membrane (TR).Conclusions: The combination of BBM and MSCs accelerated new bone for- Methods: Membrane was contoured in a rectangular parallelepiped shapemation in this model of maxillary sinus augmentation. This could allow early (8 mm length, 5 mm width and 4 mm inner height). MBCP and DBB were usedplacement of implants. as fillers in the space under the membrane. In addition, graft material was incorporated with 8% inorganic polyphosphate (polyP). Twenty adult male New Zealand white rabbits were used in this study and 4 rabbits were al-419 i Effectiveness Of autograft and Bovine derived Hydroxy lotted to each group randomly. Decortication was performed on calvariaapatite Grafted Simultaneously With implant placement in Maxillary to promote blood supply in the wound area and the membrane was fixedSinus in Space Maintenance and New Bone Formation with 4 fixation pins at each surgical site. The test groups were divided as 63
    • following: TR+MBCP (Test I), TR+MBCP+polyP (Test II), TR+DBB (Test III), inflammatory response, which is related with its degradation is often a limiting TR+DBB+polyP (Test IV), and TR without any filler served as a control. The factor for biomaterial integration within the tissue interface. A fast degradation experimental animals were sacrificed at 8 and 16 weeks after the surgery as may lead to an insufficient barrier function of the membranes. Accordingly, scheduled. Non-decalcified preparation was processed for histological and unsatisfactory tissue integration and an undesired connective tissue ingrowth histomorphometric analysis. might result. The aim of the present study was to analyze the tissue reaction to results: Control group and test group I showed the highest new bone forma- a novel bovine sourced collagen I-III based bilayered matrix after implantation tion at 16 weeks. There was no significant difference in the new bone formation in murine and human tissue. between test groups I and II at 16 weeks. All groups showed a greater amount Methods: Using the subcutaneous implantation model in CD-1 mice, the tis- of new bone formation at 16 weeks compared to 8 weeks and only test group sue integration and response to the collagen I-III-based double layered matrix III showed a statistically significant difference. Extent of new bone formation in were analyzed for up to 60 days (3, 10, 15 and 60 days). The tissue response to test group I was greater than any other groups at 8 and 16 weeks, but there was this matrix was assessed by means of general and special histological detec- no statistically significant difference. New bone formation in Test group IV was tion methodologies. The degradation of the two matrix components was fur- prominent in upper half of exophytic space at 8 and 16 weeks. thermore measured histomorphometrically. The integration of the matrix in Conclusions: Within the limitations of our experiment, it could be concluded human oral tissue was also assessed by histological analysis of histological that more favorable new exophytic bone formation was obtained when using biopsies after successful soft tissue reconstruction with this matrix. Silk fibroin DBB rather than MBCP. PolyP incorporation in both MBCP and DBB showed no as a naturally derived protein was used as a control. significant influence in the new bone formation. results: Throughout the study period, a mild inflammatory response was observed within the implantation bed of the collagen based matrix. Only few lymphocytes, predominantly macrophages and no multinucleated giant cells 421 i The Effect Of Composite Graft With deproteinized Bovine were detectable at any study time points. The matrix was detectable within Bone Mineral and Mineralized Solvent-dehydrated Bone allograft the first 30 days in its bilayered structure. Starting with day 30, however, the On Exophytic Bone Formation in rabbit Calvaria breakdown of the matrix was initiated. Correspondingly, its integration within the surrounding connective tissue began. In human tissue, good integration park Seyong (korea), Hwa-Suk Seok, Young-Hyuk Kwon, Yeek Herr, Jong-Hyuk of the matrix was observed which enabled aesthetically desirable soft tissue Chung, Seung-Il Shin regeneration. Also in human tissue no unphysiological inflammatory reaction, i.e. multinucleated giant cells was observed. Silk fibroin served also as a good Objectives: The purpose of the present study was to evaluate the osteoconduc- barrier. It induced, however, the dense influx of inflammatory cells within the tive effect of composite graft on exophytic vertical bone formation in guided bone implantation bed along with multinucleated giant cells. Accordingly, the con- regeneration with titanium reinforced e-PTFE membrane (TR). Deproteinized bo- trol material underwent faster biodegradation. vine bone mineral (Bio-Oss®, DBBM) and mineralized solvent-dehydrated bone Conclusions: The present in vivo studies in mice and humans reveal that the allograft (Puros®, SDA) were used as filler materials in the space created by TR. new collagen based matrix serves as an ideal barrier-like structure. This ma- Methods: TR was contoured in rectangular parallelepiped shape (8 mm length, terial induces no undesired foreign body response in both species and can be 5 mm width and 4 mm inner height) and sterilized with ethylene oxide before used for soft and hard tissue regeneration. No multinucleated giant cells were surgery. Twenty New Zealand adult white male rabbits (mean weight 2 kg) were observed in mice and humans. Ongoing combined in vitro and in vivo studies used in this study and 4 rabbits were allotted to each group randomly. Decor- with human endothelial and mesenchymal cells will assess the suitability of tication was performed on calvaria to promote blood supply in wound areas this matrix for complex tissue engineering. and TRs were fixed with 4 fixation pins at each surgical site. The test animals were divided into 5 groups as following: TR+DBBM (group 1), TR+SDA (group 2), TR+Mix (group 3, DBBM:SDA=1:1 in volume), TR+Layer (group 4, upper 2 ? area 423 i Biomimetic, BMp-2-Functionalisation Of deproteinised Bovine with DBBM, lower 2 ? area with SDA), and TR (control group, without any filler). Bone Confers Osteoinductivity and improves Biocompatibility The experimental animals were sacrificed 8 and 16 weeks after the surgery as scheduled. Non-decalcified preparation was processed for histological and Gang Wu (Netherlands), Ernst B. Hunziker, Yuanna Zheng, Daniel Wismeijer, histomorphometric analysis. Yuelian Liu results: New bone formation in the test group using DBBM was greater than the group using SDA. However, much more residual graft material was found Objectives: The repair of critical-sized bony defects remains a challenge in the in DBBM groups. At 16 weeks, TR+DBBM (group 1) showed a significantly fields of implantology and orthopaedics. Although healing can be aided by the higher rate of residual graft (p ‹ 0.05). TR+SDA (group 2) showed prominent transplantation of autologous bone, the supply of this tissue is limited and its cellular degradation and bone remodeling. TR+Mix (group 3) presented favor- removal is associated with donor-site morbidity. Hence, alternative bone-defect- able conditions for new bone formation and graft resorption at 8 and 16 weeks. filling materials both natural and synthetic have been sought for commercial TR+Layer (group 4) showed a distinct histological difference between the up- production on a large scale. Deproteinised bovine bone (DBB) represents one per and lower areas. New bone formation was slightly decreased at 16 weeks such material. However, this material is neither osteoinductive nor well toler- compared with at 8 weeks in group 4. ated within the bony compartments. This study was designed to functionalize de- Conclusions: It can be concluded that more favorable new exophytic bone proteinised bovine bone with a BMP-2-bearing calcium-phosphate coating, and formation could be obtained by means of composite graft of DBBM and SDA. to evaluate the osteogenesis and inflammatory activity of the end product in vivo. Sandwich bone augmentation, such as layer by layer grafting technique, was Methods: Four groups were established: (i) DBB alone; (ii) DBB bearing a also effective in new bone formation and remodeling. calcium-phosphate coating (no BMP-2); (iii) DBB bearing an adsorbed depot of BMP-2 (no coating); and (iv) DBB bearing a co-precipitated layer of calci- um phosphate and BMP-2. Coatings were prepared using a well-established 422 i Tissue reaction To a Novel Bilayered Collagen-Based Matrix biomimetic procedure. The release kinetics of a coating-incorporated and a For Guided Bone and Guided Tissue regeneration, Histological directly-adsorbed fluorescently-tagged protein depot were monitored in vitro. analysis Of animal and Human Tissue DBB granules (Geistlich) were implanted at an ectopic (subcutaneous) site in rats (n=6 animals per group), and retrieved 5 weeks later for a histomorpho- Shahram Ghanaati (Germany), Markus Schlee, Christoph Goerlach, James metric analysis of the volume densities of the bone, bone marrow, fibrous cap- Kirkpatrick, Robert Sader sule and foreign-body giant cells (a gauge of inflammatory reactivity and thus of biocompatibility). Objectives: A fast connective tissue ingrowth within a bone defect, which was results: The coating-incorporated protein depot was released more gradually augmented with bone substitute materials, negatively influences the desired than the adsorbed one (52% depletion after 35 days vs. 100% depletion after 13 bone regeneration outcome. Biomaterial research is therefore eager to pro- days). Five weeks after implantation, the volume densities of the fibrous cap- duce biocompatible membranes and matrices, which serve as barrier-like sular tissue and foreign-body giant cells were significantly lower in the BMP- elements at the interface between bone and the surrounding soft tissue. The 2-bearing-coating group than in the two non-coated groups. Consistent with64
    • baSic reSearch, Preclinical StudieSthese findings, the volume densities of bone and bone marrow were higher of the implant surface in contact with mineralized bone; referred to as “bone-in this group than in that in which BMP-2 was adsorbed directly onto the DBB to-implant contact” (BIC) and “Bone volume per tissue volume” (BV/TV), histo-granules. In the two non-BMP-2-bearing groups, no bone was deposited. morphometrical analysis was performed.Conclusions: Functionalization of DBB with a co-precipitated layer of calcium results: The median of the bone volume in the cortical area (BV/TV) of the de-phosphate and BMP-2 not only renders the material osteoinductive, but also pletion group (De) was 95.65% and 93.24 % in depletion-repletion group (DeRe)suppresses the inflammatory reactivity that is associated with the native prod- compared to 96.91% in controls (p=0.005). Whereas the bone volume (BV/TV) inuct. The attributes that are acquired by coating native DBB with a BMP-2-func- the medullary compartment showed a median of 12.39% in the depletion grouptionalized layer of calcium phosphate greatly enhance the material’s clinical (De), 11.37% in the depletion-repletion group (DeRe) compared to 12.27% in thepotential in the repair of critical-sized bony defects. control group (p=0.87). Bone to implant contact (BIC) in the cortical area showed a median of 62.73% in the De group, 76.88% in DeRe and 80.95% in Co (p=0.017). In the medullary424 i reconstruction Of Critical-Sized Bone defects Grafted With compartment BIC had a median of 26.91% in De, 22.47% in DeRe and 29.46% indifferent Biomaterials in Sheep: a Computed Tomographic analysis Co (p=0.041). Vitamin D insufficiency could similarly decrease bone remodeling activities around dental implants and potentially prolong the healing time forChih-long Chen (Netherlands) osseointegration to take place. Conclusions: The combined withdrawal of vitamin D/ calcium in combinationObjectives: To evaluate whether the different biomaterials may affect the heal- with catabolic effects on bone metabolism of aging and estrogen deficiency willing of large critical-sized bone defects manifested in cone-beam computed lead to delayed osseointegration, reversed by vitamin D administration. Eventomography (CBCT). further we expect a positive dose response effect of vitamin D supplementationMethods: 96 cylindrically drilled holes of 13 mm depth and 8 mm diameter on the site-specific bone volume.were created respectively within the proximal and distal parts of bilateral hu-merus and femurs of 12 sheep. The defects were assigned to one of the eightgroups and filled with different biomaterials: 1) no graft, 2) chips of autologous 426 i immediate and Staged implant placement in Bone defectsbone (AB), 3) deproteinized bovine bone mineral (DBBM), 4) DBBM mixed with Grafted With deproteinised Bovine Bone Mineral, Hydroxyapatite/AB, 5) DBBM upon which bone morphogenetic protein 2 (BMP2) was adsorbed, tricalcium phosphate Or autogenous Bone in an Experimental6) DBBM with biphasic biomimetic calcium phosphate coating (DBBM-CaP), Bone defect Model7) DBBM-CaP upon which BMP2 was adsorbed, 8) DBBM-CaP into whichBMP2 was incorporated during the biomimetic coating procedures. After 4- luiz a. Salata (Brazil), Antonio A. Antunes, Patricio J. Oliveira-Neto, Carla G.and 8-week healing periods, the sheep were sacrificed respectively for CBCT Pessoa, Gustavo A. Grossi-Oliveira, Paulo E.P. Fariaevaluation and grey value measurement of the defects by using 3D Accuitimo(Morita, Osaka, Japan) and Amira software (Visage Imaging Inc., San Diego, Objectives: Implant installation in fresh extraction sockets requires extra careCalifornia). Analysis of variance (ANOVA) is applied to examine the difference in order to preserve marginal bone walls from extensive resorption. Severalamong the 8 groups. previous reports claim deproteinized bovine bone mineral (DBBM); a combi-results: In Group 1, the empty defects, only minor or negligible grey value and nation of hydroxyapatite and β-tricalcium phosphate (HA/TP); and particulatewell-defined border of the defects could be observed on CBCT images after 4 autogenous bone (AB) can render less vertical bone loss when placed imme-and 8 weeks after surgery. Among the others, group 2 exhibited significantly diately with the implant. However, there is only incipient data whether a latethe lowest measured grey value at both time points. Group 8 showed the high- approach, in which osteoconductive materials could be applied and left to healest grey value compared with groups 3 to 7 after 8 weeks, but the difference bone gaps before implant installation. This study aimed at comparing the influ-was not statistically significant. ence of the timing (immediate or late approach) upon implant stability, osseo-Conclusions: Cone-beam computed tomography successfully distinguishes au- integration and alveolar crest resorption.tologous bone graft from deproteinized bovine bone mineral used in reconstruc- Methods: Six dogs underwent extractions of all lower premolars and first mo-tion of critical-sized defects in sheep. Histomorphometric analysis is needed to lars, bilaterally. Three months later four bone defects (6mm wide and 4mmclarify the effectiveness of these biomaterials in promoting regeneration. long) were drilled with trephine at one mandible side and randomly filled with DBBM, HA/TP, AB, and coagulum, respectively. Two months later four defects were created on the other side and biomaterials were used as described above425 i impact Of Vitamin d On Osseointegration together with an implant (OsseoSpeed™, Astra Tech AB, Sweden) in each site.in The Ovariectomised rat Four implants were placed contra laterally in healed defects. Animals were euthanized two months later. Implant stability was measured by RFA (Oss-Gabriella dvorak (austria), Georg Watzek, Reinhard Gruber, Alexander Fügl, tell Mentor™, Osstell AB, Sweden) at installation and after sacrifice. BiopsyAlexandra Meinl, Stefan Tangl of experimental sites were subjected to ground sections (Exact™, Apparate- beau, Germany) for histology and histometry (BA and BIC); distance of implantObjectives: Vitamin D, a systemic calcium-regulating hormone, has an ana- shoulder to higher coronal bone contact (IS-B) and alveolar crest point (IS-C).bolic effect on bone metabolism. Recent data suggests a positive impact on Statistical analysis was performed by ANOVA, Tukey and paired t-Student test.the fracture healing process and mechanical properties of callus. According to results: The staged procedure resulted in increased implant stability, asseveral epidemiologic studies a majority of the elderly population is vitamin D compared with the immediate approach (p=0.002). The BA e BIC values in thedeficient. Whether inadequate vitamin D levels or supplemental administration staged technique showed to be superior (p=0.002). The coagulum group exhib-of vitamin D has an impact on osseointegration remains unknown. Vitamin D ited higher BIC as compared with the remaining biomaterials (p=0.004) at theadministration may enhance osseointegration and thus healing time in elderly macro thread and total implant body (p=0.007). The DBBM and HA/TP groupspatients. The overall objective was to demonstrate the immanent importance revealed similar BA and BIC values compared to AB. The staged technique wasof vitamin D supplementation on enhanced bone regeneration in an estrogen found with less crest resorption (p < 0.005). The use of biomaterials did not af- _deficient population. fect (p › 0.005) the ISC-B and ISC-C measurements. The histological examina-Methods: Fifty adult female rats were divided randomly into three groups. Vi- tion revealed DBBM and HA/TP particles either in contact with implant surfacetamin depletion group with a vitamin D free diet, control group fed a standard or involved by bone. The immediate technique resulted in higher concentrationdiet and vitamin D depletion-repletion group, fed a vitamin D food after 6 weeks of particles suggesting a time-related resorptive pattern. The defects with bio-of vitamin D depletion. After a housing period of 8 weeks two titanium implants materials in the immediate group were occupied by woven bone and scarcewith a diameter of 1 mm and a length of 3 mm were placed in the tibia. At the lamellar bone. In the staged group mature bone was depicted thoroughly what-time of implant placement and scarification blood samples were collected in ever the filler.order to evaluate serum levels of 25(OH) D and parathyroid hormone (PTH). A Conclusions: Implants placed in healed defects with biomaterials or coagulumdouble fluorochrome labeling method was used to demonstrate the dynamics resulted in better stability, as a consequence of higher BIC and BA. The coagu-of healing and the influence of vitamin D. In order to quantify the percentage lum rendered better BIC compared to other materials. Late technique should 65
    • be preferable to immediate approach because of alveolar crest maintenance. In the Gillmore test, CaP-T and CaP-C showed similar initial setting times of This latter effect is explained by the so-called contact osteogenesis theory, as approximately 140 s. In contrast, the final setting time of CaP-T was signifi- the coupling process of coagulum and implant surface was somewhat hindered cantly increased to ~5 min compared to CaP-C (~4 min; p‹0.001). by physical interposition of biomaterials particles. The surgical procedure in the in vivo experiment was uneventful for all animals and all animals remained in good health during the entire 6 week implantation period. In contrast to CaP-C, CaP-T allowed unambiguous distinction of CaP 427 i repair Of Onlay Calvarial Bone Grafts under Specific cement from native bone tissue and volumetric measurements of the materi- anti-Cox 2 anti-inflammatory drug influence: Study in rabbits als by means of µCT scanning. Furthermore, CaP-C and CaP-T both showed no adverse tissue responses (e.g. inflammation or fibrous tissue formation) at the leandro Nunes (Brazil), Claudia Biguetti, Gustavo Caviquioli, Leandro Holgado, implantation site using light microscopy. Eduardo Moreschi, Mariza Matsumoto Conclusions: The incorporation of Ta2O5 as a radiopacifier into CaP cements enabled discrimination between bone substitute material and surrounding tis- Objectives: A number of molecular mechanisms regulate bone repair. Among sue by means of µCT. Compared to plain CaP cement, Ta2O5-enriched CaP them, it is known that cyclooxygenase 2 enzyme (COX-2) is essential for bone cement did not alter the biological response upon implantation in a rat femoral tissue formation and maturation. The aim of the present study was to evalu- condyle. Consequently, Ta2O5 represents an effective and biocompatible addi- ate onlay intramembranous (IM) and endochondral (EC) autogenous bone graft tive for monitoring the overall bone behaviour as well as degradation proper- incorporation in the calvaria of rabbits under specific COX-2 anti-inflammatory ties of CaP cements. drug action. Methods: Thirty six male adult, New Zealand rabbits were divided into 3 groups: Group 1) Control, treated with saline solution; Group 2) Calvaria graft, treated 429 i Comparison Of The Vertical Bone regeneration Outcome with Eterocoxib, Group 3) Iliac graft, treated with Eterocoxib, beginning three using Block and particulate Forms Of Bio-Oss® Bone Graft. days before the surgical procedure and continuing throughout all the experimen- a Histological Study Of rabbit Mandible. tal period. After 7, 14, and 30 days, the animals were sacrificed and the grafted areas retrieved for morphological microscopic analysis of the interface area. Christos koutrogiannis (Greece), Alexandros Veis, Nikolaos Dabarakis, George results: Different patterns of integration were observed between IM and EC Romanos, Irodis Barlas, Elina Petsa grafts with a decreased bone formation in the interface of IM grafts during all periods, and a similar result after 30 days between EC and Control Groups, de- Objectives: Xenografts have been employed to increase the insufficient bone spite the decreased bone formation at the 14th day when compared to IM grafts. height vertically. The aim of this study is the histological comparison of the Conclusions: From these results, it is suggested that inhibition of COX-2 en- vertical bone regeneration outcome using bovine bone graft (Bio-Oss®) in block zyme produces a negative effect in bone onlay graft incorporation by means of and particulate forms in a rabbit mandible experimental model. distinct activities for IM and EC bones. Methods: The lateral mandible area below the molars of 20 adult New Zea- land rabbits was flattened and used as the experimental site for vertical bone regeneration using standard surgical techniques. In 10 animals assigned in 428 i Tantalum pentoxide as a radiopacifier in injectable group A, cubic form block grafts (4x4 mm) were placed and stabilized using Calcium phosphate Cements For Bone Substitution shaped orthopaedic plates secured with bone screws. In the remaining 10 ani- mals assigned in group B, the particulate form of the graft was gently packed Jan Willem Hoekstra (Netherlands), Jeroen JJP Van Den Beucken, Sander CG into the custom made perforated metallic cubes (4x4 mm internally) which Leeuwenburgh, Gert J Meijer, John A Jansen were secured over the flattened lateral mandible area with bone screws. All samples were left to heal for two months. The animals were then sacrificed; Objectives: The behaviour of calcium phosphate (CaP) cements in animal the samples were retrieved, prepared for non-decalcified ground sections and testing and clinical applications is currently solely based on analysis of two- analyzed histologically. The two most central sections were taken from each dimensional (2D) histomorphometric techniques, which is not a proper repre- sample. Graft Area (GA), New Bone Area (NBA), Bone to Graft Contact (BGC) sentation of the in vivo three-dimensional (3D) situation. The reason for this is and the Maximum Vertical Height (MVH) of the new bone were measured and that non-invasive 3D imaging techniques (e.g. micro Computed Tomography, analyzed statistically. µCT) do not allow discrimination between the synthetic materials and bone due results: The healing procedure was uneventful in all experimental animals. to the chemical resemblance of CaP cements and the mineral phase of bone. A certain degree of new bone regeneration could be seen in all histological In view of this, the present study aimed at evaluating the feasibility of using tan- samples mostly close to the basal and middle areas. In group A the block talum pentoxide (Ta2O5) as a biocompatible radiopacifier in vivo. After physi- form of Bio-Oss® was integrated with the basal bone. New bone trabeculae cochemical characterization, the radiopacifying capacity and biocompatibility deriving from the basal native bone penetrated and were developed within of CaP cement containing Ta2O5 were evaluated in a distal femoral condyle the graft in form of seams covering the intra-lumen surfaces of the graft model in rats. µCT and histology were used to assess radiopacifying capacity framework. The % GA was 34.54 ±14.46 and the % NBA=10.01±6.88. In group and biocompatibility of Ta2O5 enriched CaP cement, respectively. B the particulate form of Bio-Oss® presented significantly lower GA percent- Methods: The experimental material was obtained by mixing Ta2O5 powder age (16.7±8.04, p=0.0014 ‹ 0.05). The new bone growth was observed deriving with CaP powder at a 10/90 wt.% ratio (CaP-T group); plain CaP powder was from the basal native bone and interconnecting the graft particles. The % NBA used as a control (CaP-C group). An aqueous solution of 2% Na2HPO4 was was however significantly lower than in group (A =4.83±1.89, p=0.023 ‹ 0.05). used as the liquid phase, with a liquid-to-powder ratio of 0.39 ml/g. No significant differences existed in mean BGC and MVH values: (BGC: grou- To determine the physiochemical characteristics of the materials, the crystal- pA:38.94±28.49, groupB:38.51±23.94, p=0.96 › 0.05, MVH groupA:72.76±24.48, line structure of CaP-T, CaP-C and Ta2O5 was evaluated using X-ray diffrac- groupB:62.2±17.43 p=0.36 › 0.05). tion (XRD). Furthermore, rheological properties (initial and final cement setting Conclusions: Both forms of Bio-Oss® bone graft were capable of producing times) of CaP-T and CaP-C were analyzed using a standardized Gillmore test. bone regeneration in vertical direction under the limitations of this study. The In the in vivo experiment, 6 male Wistar rats were used, observing national block form presented higher percentages of both graft and new bone volumes guidelines for the care and use of laboratory animals. Both material groups while no difference existed in new bone to graft contact percentage as well as (CaP-T and CaP-C) consisted of 6 samples. All animals alternately received in the maximum height where new bone development was observed. The new CaP-T and CaP-C in the left and right distal femoral condyle (bilateral implan- bone development patterns were different between groups and no resorption tation; 2 implant sites per animal; 3 mm diameter and 5 mm depth) with an signs in either graft forms were noticed. implantation period of 6 weeks. results: XRD analysis showed that the hybrid material (CaP-T) demonstrated diffraction peaks of Ta2O5 at identical locations while apatitic CaP peaks were 430 i Bioactive Nucleic-acid Coatings For implants slightly moved to the left, indicating a modest increase in unit cell size in the as an innovative approach For difficult Bone Conditions – CaP crystal lattice of CaP-T compared to CaP-C. an Experimental Study in Minipigs66
    • baSic reSearch, Preclinical StudieSandreas kolk (Germany), Florian Probst, Oliver Bissinger, Jochen Weitz,Christian Plank, Ralf SmeetsObjectives: Particularly in compromised bone conditions dental implants areable to expand their indications by osteoinductive coatings. The transfer ofnucleic acids makes it possible to strengthen the body´s own cell productionof particular or combined cytokines like BMP-2 and TGF-Beta or IGF withoutthe drawbacks of direct applications of recombinant proteins. Until now, thecentral issue of bioactive surfaces has been stability and release behaviour.This problem could be resolved completely by a special coating procedure withPDLLA.Methods: Pre-test series yielded an abrasion of 5% of the complete coatingduring the implantation procedure. In an experimental study with 18 Göttingenminipigs 6 coated implants with different concentrations of BMP-2-plasmidwere inserted into the maxilla in a split-mouth-design. Controls were madewith reporter gene or recombinant protein BMP-2. Evaluation of bone-implant-interface and bone regeneration took place after 14, 28 and 56 days by per-forming µCT, histology, immunhistochemistry and polymerase chain reaction(PCR).results: All coatings with nucleic acid achieved significant higher mineraliza-tion rates after 14 and 28 days (31.4% ± 4.8/64.5%± 5.1) than controls (22.9%±4.3/47.8%± 8.4) (p ‹ 0,05), so that osseointegration was more advanced in thenucleic acid therapy groups. The most effective combination seems to be BMP-2 with a DNA concentration of 12 µg, because the precedent vascularizationenhances the dimension stability of the newly formed bone. Implants coatedby recombinant protein BMP-2 osseointegrated fast, but with less stability ofdimensions.Conclusions: Results of this study first realized with human, stable coated im-plants with nucleic acids demonstrated a significant positive effect of the plas-mids concerning optimizing bone regeneration and osseointegration. Therewas only transient integration into the cell genome without organic spread, sothat nothing gets in the way of the application to humans in the future.431 i a Model for periimplantitis induction in MiceMarc Föge (Germany), Marc Menzebach, Mathias Neuschl, Jörg Wiltfang,Stephan BeckerObjectives: Development and therapy of periimplantitis is a non-resolvedemerging problem. The aim of this pilot study was to establish a model forperiimplantitis in mice as a base for tests with immune-deficient knockoutorganisms to improve the knowledge about development and progression ofperiimplantitis.Methods: In 8 mice titanium implants were inserted in the median of the pal-ate. 4 of these implants had ligatures (periimplantitis group). After two weeksof healing time the animals received a special diet enriched with sugar andflavor. After nine weeks micro-CT examinations to evaluate the periimplant tis-sue and histologies were performed.results: Dental implant insertions within the oral cavity are possible in liv-ing mice. Implants with ligatures showed significantly larger periimplant bonedefects than controls. The radiologic findings were confirmed by histology. Atthe end of the observation period, the portion of implants lost was higher inthe ligature group.Conclusions: This is the first publication to describe the insertion of dentalimplants in living mice. Additionally, it is the first time that periimplant infec-tion could be induced in that species. This model will pave the way to studyknockout-mice with reduced or even enhanced resistance to periimplantitis. 67