Miscellaneous prosthesis /orthodontic practice


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Miscellaneous prosthesis /orthodontic practice

  1. 1. Miscellaneous Maxillofacial prosthesis INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  2. 2. Maxillofacial prosthesis Tissue retained MP IMPLANT retained MP TOOTH RETAINED MP IMPLANT / TISSUE RETAINED MPCranial , Auricular , Orbital , Nasal, Nasal septum, Ocular Prosthesis . Auricular , Orbital, Facial Obturator , Mandibular Resection , Craniofacial Prosthesis Auricular, Facial Prosthesis (SUPPORT ) JPD 2OO5 www.indiandentalacademy.com
  5. 5. Miscellaneous prostheses Cranial bone prosthesis Radiation carriers Nasal prosthesis Auricular prosthesis www.indiandentalacademy.com
  6. 6. Restoration of nasal defects The vast majority of nasal defects are Secondary to neoplasm (Most) partial nasal defects Surgery Rehabilitation Total nasal defects Prosthetic restoration Para amount important ----patient desires www.indiandentalacademy.com
  7. 7. If the defects is going to be temporarily /permanently restored with a prosthesis Presurgical consultation with patients & surgeon is Necessary In partial rhinectomy defects Surgeon may advice restored Temporarily with the prosthesis Surgical reconstruction only after the suitable observation has elapsed Covering the defect with a local flap may delay the recovery of Recurrent tumor www.indiandentalacademy.com
  8. 8. Total rhinectomy cases Prosthetic restoration is preferable The prosthesis is to be constructed , the surgeon should be advised To remove the nasal bone & rest of the bone Failure to do so makes it virtually impossible to Fashion a prosthesis that duplicates presurgical Nasal prosthesis www.indiandentalacademy.com
  9. 9. Remaining nasal bone www.indiandentalacademy.com
  10. 10. Ideally a flat / concave surface is best suited to receive a prosthesis . The patient should be informed regarding benefits & limitation of prosthesis patients expectation --------- realistic Psychological evaluations & consultations should begin prior to The resection Prior to surgery , facial impression and photographs should be obtained. www.indiandentalacademy.com
  11. 11. Full facial impression are preferred Bec’z they provide useful information for the clinician to Fabricate the post surgical Nasal prosthesis . Undesirable undercuts Blocked out Petrolatum gauze www.indiandentalacademy.com
  12. 12. Temporary nasal prosthesis Approx 3 to 4 weeks following surgery Early restoration is appreciated by patients Heat polymerizing MMA preferred material . Retention Medical grade adhesive www.indiandentalacademy.com
  13. 13. Definitive nasal prosthesis Effectiveness depends upon the nature & extent of the prosthesis Flat defects in which the nasolabial fold remain are the easiest to restore prosthetically . Defects of the surgical margins that extend beyond The nasal area Difficult to restore Bec’z of exposure of the lines of juncture . www.indiandentalacademy.com
  14. 14. Margins that extend onto the Upper lip Camouflaged by facial hair Extend laterally beyond the eye Glasses will always apparent In most patients the residual tissue bed is highly mobile , particularly When next to the alae / columella Difficult to account for this mobility with impression procedure Prostheses of highly flexible material is advised more comfort to the patient www.indiandentalacademy.com
  15. 15. Defect extend onto the lip Lines of juncture in this Area was covered With a mustache www.indiandentalacademy.com
  16. 16. Defect extended laterally & inferiorly www.indiandentalacademy.com
  17. 17. Impression techniques in Definitive nasal prosthesis As in orbital defects , postural changes may result in distortions of the tissue bed . For master impression ----patient should be in upright position Elastomeric impression materials ideal for this task A facial moulage is made , using the preliminary cast a master impression tray is fabricated confined to the defect www.indiandentalacademy.com
  18. 18. Sculpting To be effective nasal prosthesis must reproduce the contour & texture of The resected nose . Another imp factor ----------placement & camouflage of the lines of juncture . In total rhinectomy defect Only small portion of the lines of juncture Are apparent with a properly sculpted Nose . If presurgical cast is not available Clay / wax should be adapted to the defect & basic contours are completed . Reference Facial photographs Family members . www.indiandentalacademy.com
  19. 19. The alae should be located in their appropriate position in relationship To the nasolabial folds. By tucking a portion of the alae into the nasolabial fold these margins Can readily be made inconspicuous . Care should be taken not to make the nose too wide in the alar region Interalar distance > Medial inner canthus distance Nares should be symmetry & constient with presurgical contours www.indiandentalacademy.com
  20. 20. Small segments of lines of Juncture is visible .most are Hidden by eye glasses & tucked into the Skin crease & folds Nares of the Prostheses Symmetry www.indiandentalacademy.com
  21. 21. C O L U M E L L a Skin Eye glass frame -----------improve the appearance of the patients Always try to place the superior & lateral margins beneath the Frame. Reproduction of surface texture is important . www.indiandentalacademy.com
  22. 22. Processing Two piece molds are adequate basic shade -----closely match the lightest area of coloration in the local area basic shade too dark ---extrinsic coloration www.indiandentalacademy.com
  23. 23. Delivery & retention Inner surface ---hollowed retention -----medical grade adhesives initial adjustments follow –up schedule constient with life of the prostheses www.indiandentalacademy.com
  24. 24. • For a nasal defect, the anterior surface of the maxilla just inferior to the nasal cavity offers sufficient thickness of bone and an optimal position for 4 mm implants. • Longer implants, 6 mm or greater, are possible in this area. • A split-thickness skin graft is needed on the sides of the defect to provide a firm nonmovable foundation for the nasal prosthesis. Retention in nasal prostheses www.indiandentalacademy.com
  25. 25. The septal cartilage must be surgically reduced anteriorly and will reduce the mobility of the tissue bed under the prosthesis and minimize the stress on the implants. will provide room for the prosthesis to engage the lateral walls of the defect and increase the stability of the prosthesis • A minimum of two implants are required, positioned in each lateral rounded nasal eminence and the abutments are connected by a bar . www.indiandentalacademy.com
  26. 26. The bar can be extended superiorly 10 to 15 mm from the abutments for better distribution of retention for the prosthesis. An acrylic resin section is constructed with the prosthesis to house the retentive elements. Retentive clips or magnets can be used www.indiandentalacademy.com
  27. 27. Partial nasal prostheses More of the lines of juncture between prostheses & adjacent margins will be exposed Margins –feathered & colored Acceptable result www.indiandentalacademy.com
  28. 28. Restoration of auricular defects Defects secondary to congenital malformations , trauma … Pre operative consultation Extremely valuable Feathering of the margins & the incorporation of appropriate surface detail . If surgical reconstructed of the auricle is not contemplated Entire ear should be removed ---leaving a flat tissue bed & lined with scalp flap ----making it ideal base . The tragus should be retained Bec’z this structure is less obvious anterior line of juncture bet the Prostheses & the skin . www.indiandentalacademy.com
  29. 29. Residual tissue tag No retentive value Prevent sculpture & positioning of of the prostheses ear . Temporary auricular prostheses In most patient tissue bed is organized sufficiently 3 weeks after surgery fabrication ----heat polymerization of acrylic resin ---periodic adjustment & relining www.indiandentalacademy.com
  30. 30. Definitive Auricular prostheses Impressions Unlike orbital defects ,tissue beds in the auricular area are not displaceable , Distortions do not results from postural Changes Impression can be obtained pt lying on his side In a supine position . Condylar movements closely examined , Results in Tissue bed mobility www.indiandentalacademy.com
  31. 31. Tissue bed mobility Can affect the Margin placement , Tissue coverage , Retention of the prosthesis . Impression materials –reversible hydrocolloid, rubber base impression material. www.indiandentalacademy.com
  32. 32. Auricular prosthesis Impression of the Defective side Patient Position Defective ear facing up External auditory Meatus ----blocked with wet gauze . Impression mat reversible hydrocolloid Paper clips –reinforcement , Plaster Paris –backing . Impression of the Nature side www.indiandentalacademy.com
  33. 33. Sculpting If presurgical cast is available it is reproduced in wax & compared to the remaining ear Appropriate changes are made in the basic contours & the wax ear is positioned & adapted to the defect To achieve symmetry in all planes with the opposite side www.indiandentalacademy.com
  34. 34. Preoperative cast Not available Sculpting Beginning Donor technique Time consuming difficult task Dividing the cast of the ear Into equal sections Contours can be easily verified Selection ; Person with ear contours closely Mimic those of the patient www.indiandentalacademy.com
  35. 35. Orientation lines for positioning of auricular prostheses Vertical line Above the helix – EAM— LOBE Horizontal line Helix --- EAM— TRAGUS (beyond ) Defect ear www.indiandentalacademy.com
  36. 36. Orientation lines in stone cast www.indiandentalacademy.com
  38. 38. LAND MARK LOCATION OF THE LAND MARKS Superaurale (sa) Highest point on the free margin of the auricle Subaurale (sba) Lowest point on the free margin of the earlobe Preaurale (pra) Most anterior point of the ear located just in front Of the helix attachment Postaurale (pa) Most posterior point on the free margin of the ear Otobasion Superius (obs) Point of attachment of the helix in the temporal region; determines the upper border of the ear Insertion Otobasion inferious (obi ) Point of attachment of the ear lobe to the cheek; determines the lower border of the ear insertion www.indiandentalacademy.com
  39. 39. A N T E R I O R View P O S T E R I O R View www.indiandentalacademy.com
  40. 40. Alginate impression Posterior section Posterior & anterior gray investment Gray investment Molds –sprues & ventswww.indiandentalacademy.com
  41. 41. Entire surface must be stippled to match the skin texture of the patients proper stippling is important Without it texture of the adjacent skin can never be suitably Matched External tinting may be very difficult Provides mechanical retention for the Extrinisic colorants & lengthens the Period of service of the prostheses www.indiandentalacademy.com
  42. 42. A residual tragus will serve to camouflage approx 25 % of the anterior margins . Processing The wax ear is invested in a manner to construct a three –part mold Using flexible materials to remove the Casting from the mold without tearing Material Base shade Processing Selection Determination Surface characterization www.indiandentalacademy.com
  43. 43. Margins is feathered anteriorly Side burns nicely Camouflage Lines of juncture www.indiandentalacademy.com
  44. 44. Three part mold www.indiandentalacademy.com
  45. 45. Conventional retentive devices Used in auricular prosthesis retention Eye glass Tissue adhesives Extension of the prostheses into ear canal www.indiandentalacademy.com
  46. 46. • The use of transcutaneous implants in the temporal region for auricular prostheses has shown to be an effective reconstruction option . • The temporal bone has sufficient thickness to accept a 3 or 4 mm implant. www.indiandentalacademy.com
  47. 47. A minimum of two implants are needed, positioned approximately 18 mm from the center of the external auditory meatus and 15 mm from each other. The abutments are joined by a bar constructed in a C-shaped design to improve the stability and retention of the prosthesis • The bar can be extended 10 to 15 mm beyond the abutments for better distribution of stability and retention. www.indiandentalacademy.com
  48. 48. Recent techniques in Retention of auricular prosthesis The use of craniofacial implants for retention of extra oral prostheses Excellent support & retentive abilities Use of magnets is advantageous over the bar & clips for maintenance . use of composite bar secured into the implants by gold screw . magnets incorporate into the fitting surface of the prostheses www.indiandentalacademy.com
  49. 49. Implant abutment In place Composite bar secured with Gold screws Magnets – tissue surfacewww.indiandentalacademy.com
  50. 50. Nd –Fe –B magnet Sealing Micro laser welding www.indiandentalacademy.com
  51. 51. Retentive bar connects 2 Implants www.indiandentalacademy.com
  52. 52. BTE HEARING AID (MODULE ) www.indiandentalacademy.com
  53. 53. Prosthodontic stents & splints during therapy Prosthodontic stents & splints may provide significant benefit to the Radiation therapist by facilitating delivery of therapy to local areas & thereby limiting post therapy morbidity . Stents employed to Protect / displace vital structures , Locate diseased tissues in repeatable positions During treatment , position the beam , Carry the radioactive material dosimetric device to the tumor site , usually confined to The head & neck regions www.indiandentalacademy.com
  54. 54. Positioning stents Peroral cone positioning devices Shielding Recontouring tissues to simplify dosimetry Positioning radioactive sources Use of Prosthodontic Splints and Stents During Radiation TherapyUse of Prosthodontic Splints and Stents During Radiation Therapy www.indiandentalacademy.com
  55. 55. Maintaining position of structures to be treated This type of stent is used primarily for Tongue lesions being treated with external Radiation . Many radiation therapists use a cork to which a tongue blade is taped to confine The Tongue within the lingual borders of the mandible An inferior position of the tongue & mandible Therapist to lower the Radiation field & spare Significant amounts of parotid glands www.indiandentalacademy.com
  56. 56. An inter occlusal stent is prepared that extends lingually from Both alveolar ridges with a flat plate of acrylic resin ; Serves to Depress the tongue within the lingual borders of the Body of the mandible . A hole is made in the anterior segment in which the tip of the tongue Placed to establish a reproducible positions Prostheses for the dentulous patients www.indiandentalacademy.com
  57. 57. Extension used to depress theExtension used to depress the tonguetongue Tip of the tongue fits in this holeTip of the tongue fits in this hole COMBINATION OF BITE OPENING & TONGUE POSITIONING STENT www.indiandentalacademy.com
  58. 58. 25 mm25 mm FOR EASY INSERTION SHOULD NOT EXCEED 25 MM www.indiandentalacademy.com
  59. 59. www.indiandentalacademy.com
  60. 60. Prostheses for edentulous patients Requires maxillary & mandibular impressions , With the use of an interocclusal record , cast are mounted on the articulator, Two thickness of base plate wax ----- mandibular record base to form the portion of the stent --depress the tongue An occlusal index should be incorporate into record bases If the existing denture is adequate ---duplication of the dentures should be carried out www.indiandentalacademy.com
  61. 61. Duplicated dentures returned to the mouth , they are lined with tissue Conditioned material , & tongue is positioned as before . Some clinician prefer intra oral fabrication of the stent using a direct technique www.indiandentalacademy.com
  62. 62. positioners –direct technique www.indiandentalacademy.com
  63. 63. Removing structures from the radiation field This type of stent is valuable when treating lesions involving the mandibular alveolus, buccal mucosa, and posterolateral border of the tongue. The stent separates the mandible from the maxilla, thus sparing the maxilla from the effects of irradiation. In addition, opening of the mandible often lowers the field sufficiently to eliminate much of the parotid gland from the radiation field. This stent is constructed in a fashion similar to the stent used to depress the tongue vertically. The vertical opening should allow maximum separation of the maxilla and mandible within the limits of comfort. www.indiandentalacademy.com
  64. 64. Removing structures from radiation field 25 mm25 mm FOR EASY INSERTION SHOULD NOT EXCEED 25 MM www.indiandentalacademy.com
  65. 65. Large one-piece stents are often difficult to insert, particularly when the patient begins developing radiation mucositis and trismus. A two- or three-piece stent may be inserted and removed more easily and Therefore is more likely to be used by the patient and radiotherapist. www.indiandentalacademy.com
  66. 66. Some superficial oral squamous cell carcinomas in accessible regions, such as the anterior floor of the mouth and the hard and soft palate, often may be treated with the use of a peroral cone. The obvious advantage of such an approach is that structures such as the mandible and salivary glands are spared from the effects of radiation. Such stents are usable in both dentulous and edentulous patients and assure repeatable positioning of the peroral cone during therapy Positioning peroral cones www.indiandentalacademy.com
  67. 67. For an edentulous patient, mandibular and maxillary record bases are fabricated. The actual peroral cone or a cylinder of the same diameter as the Cone, is used to form an acrylic resin ring 5 to 6 cm long. Tinfoil (O.OOl-inch) is wrapped around the cone to ensure its separation from the auto-polymerizing methyl methacrylate that is used to form the ring. Fabrication procedure Of peroral cone www.indiandentalacademy.com
  68. 68. Stent –positioning peroral cone www.indiandentalacademy.com
  69. 69. IndicationsIndications Small localized, accessible, superficial lesions of the oralSmall localized, accessible, superficial lesions of the oral tongue, floor of the mouth or soft palatetongue, floor of the mouth or soft palate www.indiandentalacademy.com
  70. 70. Radiation mucositis www.indiandentalacademy.com
  71. 71. With the radiation therapist present, the acrylic resin cylinder is attached to the maxillary record base with dental modeling plastic, and the acrylic resin cone is centered over the lesion. This task is most easily performed in the presence of the patient, but the cast may be used on occasion where the lesion is easily accessible and visualized If the dorsum of the tongue protrudes into the end of the cone, a wax extension may be attached to deflect the tongue. Using a beveled cone will usually serve same purpose. www.indiandentalacademy.com
  72. 72. Shielding This type of stent is only amenable for use with electron beam therapy. Studies have shown (Wallace, 1971) that a 1 cm thickness of Cerrobend*, a low-fusing alloy, will prevent transmission of 95% of the electron beam from an 18 MeV machine. When such radiation sources are employed, important structures can be shielded by the placement of a stent. Lesions of the buccal mucosa, skin, and alveolar ridge may therefore be treated, and effective shields may be fabricated to protect the tongue and the opposite side of the mandible. www.indiandentalacademy.com
  73. 73. When obtaining the mandibular impression, dental modeling compound is used to displace the tongue away from the tray on the side for which the stent is to be fitted. If the tongue is not displaced at that time, the mandibular cast must be trimmed 1 cm space is created between the tongue and the alevolar ridge. Three or four strips of base plate wax are softened and placed between the teeth, and the instrument is closed to form an occlusal index . www.indiandentalacademy.com
  74. 74. Shielding www.indiandentalacademy.com
  75. 75. Fabrication procedure (Shielding ) A wax rim 1 to 1 ½ cm thick is prepared to fit into the reduction of the cast . Softened wax is placed inside the cast & the instrument is closed so that a ring outline form can be molded Lingual ext of wax should be hollowed to create a cavity 1 cm thick . Processed by ---MMA www.indiandentalacademy.com
  76. 76. Lead is not suitable material for shielding Cerrobend alloy as effective as lead in preventing the passage of an electron beam . Pouring the stent around the corner Block out with clay Back scatter prevented by -----Auto polymerizing MMA resin www.indiandentalacademy.com
  77. 77. Positioning dosimetric device Radiotherapist occasionally concerned Regarding CRD /ARD LITHIUM FLUORIDE CAPSULES ----used as a Dosimetric are an accurate & efficient means of Determining dosage locally . A stent may be employed to position the stent . www.indiandentalacademy.com
  78. 78. Lithium fluoride carrier –positioning dosimetric device www.indiandentalacademy.com
  79. 79. Recontouring tissues to simplify dosimetry This type of stent is advantageous when treating skin lesions associated with the upper and lower lips. When the therapist adjusts the beam for the midline, the dosage delivered will be less at the corners of the mouth because of the convex curvature of the lips and face in this region. A stent can be employed to flatten the lip and corner of the mouth, thereby placing the entire lip in the same plane. Such stents often are combined with a shield. www.indiandentalacademy.com
  80. 80. Positioning radio active Source Selected superficial oral lesions effectively treated by Placement of prescribed distance from the radiation source . For treament of buccal / palatal Lesion ----placement of radioactive source in a maxillary trial denture itself . www.indiandentalacademy.com
  81. 81. www.indiandentalacademy.com
  82. 82. Positioning radioactive source by after loading These stents are similar to those that carry a live source, except that the radioactive source is placed in the stent after the stent is secured in its desired position. Therefore, undue contamination of the clinician is avoided. This prosthesis is useful primarily in treatment of accessible superficial lesions. The stent is fabricated in much the same fashion as radiation carriers except that Polyethylene Tubing is placed a prescribed distance from the tumor . www.indiandentalacademy.com
  83. 83. Radioactive source inserted after the carrier positioned Intraorally www.indiandentalacademy.com
  84. 84. Lesions of the retromolar trigone, buccal mucosa, and tongue predispose to cheek and tongue biting. Mucositis and edema during radiation therapy may accentuate this problem. A stent can easily be fashioned to displace the tongue and/or buccal mucosa and help alleviate this problem. This stent overlays the teeth and may be fashioned of mouth guard material* on dental stone casts. Prevention of tongue & cheek biting www.indiandentalacademy.com
  85. 85. In some situations a fluoride carrier can serve the same purpose. This stent prevents large metal restorations from directly contacting oral mucous membranes and, therefore, prevents localized severe radiation mucositis secondary to backscatter. www.indiandentalacademy.com
  86. 86. Individually constructed vaginal carriers for intracavitary therapy using either iridium 192 or radium in specific patients with carcinoma of the vagina, recurrent endometrial carcinoma of the vaginal vault, and carcinoma of the cervix with a narrow vaginal vault have recently gained favor. Vaginal carriers www.indiandentalacademy.com
  87. 87. Cranial implants Etiology of cranial defects During repair of compound skull fracture Bone flap reimplanted during elective craniotomy become infected . Excision of osteomas surgically planned external decompression craniotomies . congential malformation www.indiandentalacademy.com
  88. 88. Indication for cranioplasty Disfigurement & mechanical Vulnerability Small defects 2-3 cm Location ; Above the orbital rim , Nasion Cosmetic reasons Repair for Large defects 8-10 cm POJunction Brain protection www.indiandentalacademy.com
  89. 89. Most cranial defects some variable Proportion of Cosmetic Mechanical Aspects Decision regarding Cranioplasty must be influenced by Age Prognosis Activity level Specific condition Of the scalp Poor candidates for surgery External prostheses fabricated as an integral part of the wig Cosmesis Protection www.indiandentalacademy.com
  90. 90. www.indiandentalacademy.com
  91. 91. Immediate repair of the cranial defects is not recommended Bec’z of overt / latent infection Cranioplasty delayed for ---6 -12 months. Interim protection External prostheses Ideally even in the absence of infectious complication 2-3 mon Required for proper organization & revascularization of flaps www.indiandentalacademy.com
  92. 92. Methods of cranioplasty Two basic methods Osteoplastic Reconstruction Restoration with alloplastic material Autogenous bone graft Radiodensity It’s a viable part of the host tissue psychological benefits www.indiandentalacademy.com
  93. 93. Autogenous bone graft Radiodensity It’s a viable part of the host tissue psychological benefits Possible absortion& Loss of contour availability of material diff in cosmetic www.indiandentalacademy.com
  94. 94. Composite autogenous Graft To close small through & Through defects Free autogenous graft -----------rib / iliac crest Ribs are most commonly used Bec’z availability ,retrievability , Less defomorability www.indiandentalacademy.com
  95. 95. More recently Habal et al ---used a polyurethane terephthalate to restore the Cranial defects Alloplastic implants Metals – Tantalum Inert & malleable , .015 inch perforated sheets , The implant inlayed into ledge created Removing a thickness of the outer table of Adjacent skull equivalent to the thickness of the tantalum . Removal of the contamination by –Nitric acid www.indiandentalacademy.com
  96. 96. Mesh of polyurethane terephthalatewww.indiandentalacademy.com
  97. 97. Titanium Strong , can be strain hardened radiodensity .61 mm thick Tissue acceptability of the implant is enhanced by anodizing 80% H3 po4 10% H2 so4 10% H2o www.indiandentalacademy.com
  98. 98. Experimental trials Vitallium Ticonium Stainless steel 316 austenite form Disadvantages Thermal conductivity ----precipitate head ache Malleable –leads deformation www.indiandentalacademy.com
  99. 99. Principle advantages of the metals Malleable ---enables the clinician to shape them to any configuration . require one incision readily available . www.indiandentalacademy.com
  100. 100. Autopolymerizing MMA Radiolucent Readily available in sterilized premeasured Packets of monomer & polymer . Poor thermal & electrical conductivity . Mixing a polymer & monomer in polyethylene Bag & apply the bag on the defect Prevents monomer contamination ‘ Easy handling www.indiandentalacademy.com
  101. 101. Some clinicians prefer numerous perforation into the prostheses Maintain fibrous connective tissue Proliferation For stability Fluid may accumulate beneath implant Can pass to the outer into Subgaleal space Can cause tissue reaction monomer toxicity difficulty in contouring www.indiandentalacademy.com
  102. 102. Heat polymerizing MMA IMPRESSION ---- defective part with hydrocolloid Large cranial defects smaller defects Scalp –complete shaving Shaved border of 5cm around the Bone margins is necessary When possible clinician should attempt to palpate & mark the margins of the inner table of bone Locating the inner table aids in determining the angle necessary for Contouring the cast to form a margin that will fit . www.indiandentalacademy.com
  103. 103. Parietal temporal defect Skull radiographs www.indiandentalacademy.com
  104. 104. Larger defect www.indiandentalacademy.com
  105. 105. Impression techniques Patient position ------upright Material –reversible hydrocolloid Thickness of impression ---5 cm Silicone ---best material for impression Viscosity Indelible pencil marking more clearly delineated in the Impression www.indiandentalacademy.com
  106. 106. Impression obtained with silicon impression material www.indiandentalacademy.com
  107. 107. Prior to preparation Of the cast Consultation with Neuro surgeon Design of the cranial implant Inlay the implant into the defect Remove the outer table adjacent to the defect Forming a ledge into which implant is fitted Controversies Create a thin lip that rests on the unaltered Outer table around the margins www.indiandentalacademy.com
  108. 108. Prefabricated cranial implant Inlay type Onlay type Extending thin lip www.indiandentalacademy.com
  109. 109. Wax pattern fabrication Curing –conventional manner Making of Perforation . Sterilization ---ethylene oxide at low temp Prosthesis secured by wire / synthetic sutures . Impression mat -----bees wax 2/3 + petroleum jelly 1/3 Described by Elkins www.indiandentalacademy.com
  110. 110. HMMA cranial bone prostheses www.indiandentalacademy.com
  111. 111. Other modification Combination of autopolymerizing resin + stainless steel mesh Suitable in children's with thin cranium Polyethylene some Properties similar to MMA Gas sterilization . Silicone Tissue compatability +flexiblity Medical grade silicone In 3 forms Blocks –carved to desired shape Heat vulcanization form Room vulcanization form www.indiandentalacademy.com
  112. 112. Conclusion There are many individual presentation& varying challenges in supplying patients with prostheses for maxillofacial defects & the restorative dentist has to be imaginative & innovative . As for any other successful treatment , the important Feature is to be aware of the principles & to stick with them www.indiandentalacademy.com
  113. 113. References ( Books) Text book of maxillofacial prosthesis VAROUJAN CHALIAN Text book of maxillofacial Prosthetics WILLIAM R. LANEY Maxillofacial Rehabilitation Beumer www.indiandentalacademy.com
  114. 114. References (journals ) Cranial prostheses JPD 1998 ;79 :229 -231 Modification of Cranial implant prostheses JPD 1984 ;52 :414 -417 Retention of facial prostheses JPD 1980;43:552-560 Auricular retention JPD 2001 ;86:386-389 www.indiandentalacademy.com
  115. 115. Thank you For more details please visit www.indiandentalacademy.com www.indiandentalacademy.com