1) A new digital technique is described for reproducing the subgingival part of a tooth prepared using the biologically oriented preparation technique (BOPT) which involves no finish line, along with the adjacent dentogingival sulcus.
2) Key steps involve double probing to measure bone levels, supragingival and subgingival tooth preparation using a diamond bur, and cementing a provisional restoration to shape the gingiva.
3) Multiple intraoral scans are taken at different stages to digitally capture the prepared tooth and surrounding gingiva both with and without the provisional in place. These scans are used to create a "virtual gingiva" and accurately align the digital model.
loading protocols in dental implants about indications and contraindications of conventional , immediate,progressive and delayed loading of dental implants
Indian Dental Academy: will be one of the most relevant and exciting training
center with best faculty and flexible training programs for dental
professionals who wish to advance in their dental practice,Offers certified
courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry,
Prosthetic Dentistry, Periodontics and General Dentistry.
Precision attachments in prosthodontics/ orthodontics short term coursesIndian dental academy
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Failures in Fixed Partial Denture
(Prosthodontics FPD- Dental science)
Various types of failures in the fabrication of fixed partial denture
Dr.Sachin Sunny Otta
St.Gregorios Dental College,Kothamangalam,Ernakulam
Orientation jaw relation /certified fixed orthodontic courses by Indian denta...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
This seminar deals with implant-related complications that lead to implant failure.this also discus diagnostic criteria and preventive methods for an implant failure.
loading protocols in dental implants about indications and contraindications of conventional , immediate,progressive and delayed loading of dental implants
Indian Dental Academy: will be one of the most relevant and exciting training
center with best faculty and flexible training programs for dental
professionals who wish to advance in their dental practice,Offers certified
courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry,
Prosthetic Dentistry, Periodontics and General Dentistry.
Precision attachments in prosthodontics/ orthodontics short term coursesIndian dental academy
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Failures in Fixed Partial Denture
(Prosthodontics FPD- Dental science)
Various types of failures in the fabrication of fixed partial denture
Dr.Sachin Sunny Otta
St.Gregorios Dental College,Kothamangalam,Ernakulam
Orientation jaw relation /certified fixed orthodontic courses by Indian denta...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
This seminar deals with implant-related complications that lead to implant failure.this also discus diagnostic criteria and preventive methods for an implant failure.
A lecture for 5th stage dental students.
any questions or notes please contact me on theses links :
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Congenitally Missing Bilateral Incisors with Single-Tooth Implants: Clinical ...Abu-Hussein Muhamad
Agenesis, the absence of permanent teeth, is a common occurrence among dental patients. The total incidence of tooth agenesis is about 4.2% among patients that are seeking orthodontic treatment and with the exception of third molars, the maxillary lateral incisors are the most common congenitally missing teeth with about a 2% incidence . Esthetically correcting congenitally missing maxillary lateral incisors is a common challenge that every orthodontist and dental team will face, and dentists must consider the treatment options that are most appropriate for each patient.
This paper describes the therapeutic use of osseointegrated implants to replacε congenitally missing upper lateral incisors. Highlighting the importance of the Orthodontic/Restorative interface.
FINITE ELEMENT ANALYSIS AND STATIC LOADING IN DENTAL IMPLANT WITH INNOVATIVE ...indexPub
Objective: The purpose of this study is to examine how different crown materials affect stress transformation and distribution around both dental implants. To do this, integrated and combined crowns were built, modelled, and tested under static axial loads using various material combinations. The biomechanical response was then examined. Methods: A validated three-dimensional finite element (FE) models of crown supported by implant was developed by to evaluate the effect of the different type of material (E max, zirconia, composite) on the short implant. After the FE models had been validated, simulations utilizing various configurations of various crowns fixed to two distinct types of implants were run and subjected to static loading to ascertain the distribution of stresses inside the bone around the implants. Result: The comparative results showed that manufacturing the crown using softer material (i.e., materials with lower elastic modulus) reduced the stress distribution in crown, implant and cancellous bone. It may refer to this phenomenon that softer material can absorb more energy from the applied compressive load, and result in transferring less energy to the implant and jaw bone. However, this effect was not significant on cortical bone compared to the cancellous bone. Combination of different materials for design and manufacturing the crown can alter the biomechanical response and could be beneficial for decreasing the stress distribution in implant and spongy region of jaw bone when stiffer material is needed to be covered in upper surface of the crown. In addition, the results suggests that shorter implant can increase the stress distribution in both cortical and cancellous bone. Conclusion: by using stiff material the stress will increase on the parts of implant and the surrounding bone which may led to failure of implant or bone resorption around of the implant, in other way by using less stiffer material the possibility of success will be increased and also the success rate of the implant is increased, also before deciding which implant size and length are used you select which type of the prosthetic will be used.
journal cub presentation on Bps denture/biofunctional prosthetic systemNAMITHA ANAND
watch video links below for better understanding
https://www.youtube.com/watch?v=_sR2Ip5p9RE
its a series of videos 1-7 beautiful videos explaining the construction of BPS DENTURES - step by step
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
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Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
JOURNAL CLUB PRESENTATION IN PROSTHODONTICS on biologically oriented preparation technique (BOPT)
1. DIGITAL PROTOCOL FOR
CREATING A VIRTUAL GINGIVA
ADJACENT TO TEETH WITH
SUBGINGIVAL DENTAL
NAMITHA AP
II nd MDS
DEPT OF
PROSTHODONTICS
COORG INSTITUTE OF
DENTAL SCIENCES
Agustín-Panadero R, Loi I, Fernández-
Estevan L, Chust C, Rech-Ortega C, Pérez-
Barquero JA.
Journal of Prosthodontic Research. 2019
Nov 28.
JOURNAL CLUB
PRESENTATIO
N
3. INTRODUCTION
Dental preparation techniques for restoration by fixed prostheses are
undergoing a significant change
horizontal finish lines (short or long chamfer, straight shoulder,
beveled shoulder, etc.) are now being replaced by preparations without
finish line, following the biologically oriented preparation technique
(BOPT)
4. BIOLOGICALLY ORIENTED
PREPARATION TECHNIQUE
This procedure is characterized by
the creation of a non-dental,
prosthetic finish line situated at a
depth of 0.5–1 mm in the periodontal
sulcus, first preparing the tooth with
a vertical axial plane between the
anatomical crown and the root.
Intraoral
scanners
Inefficient in
detecting
subgingival dental
anatomy
Provisional prosthesis is
removed for impression
taking
gums collapse onto the
tooth
impossible to obtain a
digital record of the
dental preparation, the
gingival sulcus, or its
emergence
CORRECT HEALING
OF SURROUNDING
GINGIVAL TISSUES
CERVICAL
EMERGENCE AND
OVOID
CONTOURING
healthy gingival adaptation with the same
shape as gingival tissue adapted to the
convex emergence of the natural
emergence profile of an untreated tooth
Provisional
crown
5. OBJECTIVES
to describe a digital technique for reproducing the subgingival part of
a tooth prepared without finish line (BOPT) and the adjacent dento-
gingival sulcus without variations derived from gingival collapse.
This technique is able to create a ‘virtual gingiva’ with the same
emergence morphology as when the provisional prosthesis is
cemented in place on the tooth.
6. MATERIALS AND METHODS
Tooth preparation
• The exact measurement to the bone level must
be determined as this structure must remain
untouched by dental preparation
1.Double probing
2.Supragingival dental preparation
3.Subgingival dental preparation
BOPT procedure
described by Loi
7. DOUBLE PROBING
periodontal chart and a series of radiographs
Distance from the gingival margin to the bone crest is
measured in order to confirm that the teeth present no
bone problem and that both cortices are intact (2.7–3.2
mm)
position of the tooth’s cemento-enamel junction - depth of
dental preparation inside the gingival sulcus
GIGIVAL
SULCUS(SULCULA
R EPITHELIUM)
JUNCTIONAL
EPITHELIUM
(ATTACHMENT)
PROBED WITH
PERIODONTAL
PROBE
1.6–2.4
mm
free from
signs of
inflammati
on,
alterations
in color,
hemorrhagi
ng and
bacterial
plaque
When it is resting on the bone and laterally on the tooth, it is
withdrawn gently in coronal direction in touch with the root
anatomy until it reaches the start of anatomical crown
emergence.
At this point the movement stops and the distance to the gingival
margin is measured. This distance will determine the extent of
8. SUPRAGINGIVAL PREPARATION
incisal edge or occlusal face is reduced by 2 mm
beveling the vestibular face of the incisal edge or the external slope
of the functional cusp to an angle of approximately 45 º
axial walls are reduced by 1 mm supragingivally with a conical shaft
turbine diamond bur, of 1.4 mm diameter, with 100 μm
granulometry.
chamfer finish line 2 mm from the gingival margin.
In the interproximal area, scalloped dental preparation is carried out
following the anatomy of the papilla but without touching it.
In cases of retreatment with fixed prostheses, this step should be
omitted as the tooth has already undergone subgingival preparation
9. SUBGINGIVAL PREPARATION
milling of both tooth and gum are performed
simultaneously (rotary gingival curettage) with a 1.2 mm
diameter diamond flame bur with 100 ƒÊm ganulometry.
Bur is inserted in the gingival sulcus obliquely at an angle of
10 -15 0 to the dental axis
Tooth is milled with one side of the bur while the gingiva is
curetted with the other side and the bur tip.
When the first millimeter of the anatomical crown
emergence has been milled, to prevent the bur tip from
damaging part of the tooth root, the angle of the bur is
altered so that it runs parallel to the tooth axis; in this way,
the convexity of the anatomical crown beyond the cemento-
enamel junction is eliminated.
To complete preparation, the bur is inclined slightly in
occlusal/incisal direction to give the axial walls of the tooth
the correct convergence (6 o).
10. cell differentiation for the formation of new gingival tissue
new structuring of the periodontium around the prosthetic emergence’s new
morphology
creates a blood clot in the apical area
stabilized by the design of the provisional prosthesis
milling the tooth and gum at the same time
controlled de-epithelization of the
sulcus’ free and junctional epithelium
vertical axial plane
The function of the
provisional prosthesis is to
shape a new prosthetic
angular component with a
new prosthetic cemento-
enamel junction (PCEJ)
situated in the gingival sulcus
at a depth of 0.5- 1 mm
(respecting biologic width)
11. Provisional must not be removed from the tooth for the first four
weeks in order to avoid gingival healing problems.
Later, until the complete maturation of soft tissue (8–12 weeks), the
shape of the provisional can be modified to achieve the correct
modeling of the gingival margin.
The provisional is fabricated by the laboratory technician from an
initial pre-treatment model.
The technician mills the tooth model, which then acts as a post to
support the (juxta-gingival) provisional prosthesis.
The provisional is fabricated from acrylic resin of very fine thickness
(0.3 mm).
12. This will function as an “egg-
shell”provisional, facilitating relining
without compromising its seating.
When the tooth has been prepared,
the fit of the provisional is checked
and then it is relined with self-
polymerizing acrylic resin (Sintodent.
Sintodent S.R.L).
Lastly, while the relining material is
setting, the provisional can be
adjusted on the tooth and inserted
0.5–1 mm inside the gingival sulcus
(controlled invasion of the gingival
sulcus)
The provisional prosthesis will
remain cemented on the tooth until
the gingival tissues have matured
completely
13. IMPRESSION TECHNIQUE
It is important to follow an impression taking protocol that will
reproduce the real position of the gums when the provisional is in
place on the prepared tooth, and that is reproducible and does not
depend on clinical skill.
Captures data in three dimensions
produces STL files of the gingiva, first scanning the occlusal face,
followed by the vestibular and lingual aspects.
The data obtained are downloaded from the 3 M Connection Center,
providing one STL file per scan.
14. CHAIR SIDE PROTOCOL STEP BY
STEP
creates a virtual model of the
gingiva( used to fabricate the crown
)
Six intraoral scans generate six
types of STL file.
The first STL file (STL-1) is obtained
by scanning the provisional
prosthesis cemented onto the tooth,
reproducing its morphology and
adjacent gingival emergence.
When doing this, it is important to
reproduce the other teeth in the
arch
15. The second scan captures the provisional crown removed from the mouth.
It is important to reproduce the intrasulcular emergence of the cervical area
of the crown as this will define prosthetic invasion of the gingival sulcus,
both vertically and horizontally under conditions of periodontal health.
To do this, the prosthesis is placed on a vertical wax rod, supporting the
incisal edge with the internal part and emergence placed upwards
In this way, the crown’s entire internal surface and peripheral cervical area
can be scanned
16. Then, to reproduce the whole crown and ensure best-fit alignment of
the surfaces, the prosthesis is replaced on the wax rod the other way
up, placing the internal part and emergence on the rod with the
incisal edge upwards, so that the complete morphology and the
prosthesis peripheral cervical emergence can be scanned
Accurate reproduction of the cervical part is of key importance for
correct alignment of the two scans, which are then used to generate a
3D virtual reproduction of the whole provisional, an STL file (STL-2)
of the complete prosthetic anatomy.
17. The third scan captures the teeth prepared with BOPT, recording all
tooth walls and the gingival area which will have collapsed due to the
removal of prosthetic support (STL-3).
It is also important to reproduce the rest of the arch (both teeth and
gingival tissue) in order to ensure better accuracy in future
alignments.
18. The fourth scan records the antagonist arch (teeth and gingival
tissue).
The fifth and sixth scans register occlusion in maximum
intercuspation on the left and right sides.
Exported to design software to create a digital model of the gums.
This ’virtual gingiva’ process begins by superimposing STL-1
(patient’s arch with bonded provisional[s]), which acts as a reference
for the entire alignment process, and STL-3 (patient’s arch with
prepared tooth stumps), which acts as a ‘floating’ archive.
For correct alignment, it is important to select the surfaces that are
common to both STL files.
When digital alignment has been performed, its quality can be
checked by creating a color map, which will highlight any surfaces
presenting variations between the scans
when any variations between one scan and the other are identified,
the corresponding surfaces should be eliminated from the points
selected for purposes of alignment before repeating the alignment
19. Most of the superimposed areas that
represent hard tissues show an error
of + - 20 micrometers, with the
exception of the central areas
In STL 3 the central incisors have
been milled.
Grey area represents those parts of
the STL-3 file that does not contain
information in either of the two files
(in this case STL 3), which
corresponds to the area of incisor
milling.
Interproximal area, as well as the
gingival sulcus, are typically ‘noisy,’
so these should be omitted when it
come to performing best fit.
Soft tissues have less dimensional
stability than hard tissues so these
should also be omitted when it
A color map that includes + - 200 micrometers,
whereby any deviation –any area subject to
error –within this range will be marked in color,
taking on the most extreme color on the map’s
color gradient
20. STL-1 (reference) and STL-2(floating)
are then aligned.
To do this, only the provisional crown in
the complete arch (STL-1) is selected
for alignment with the visible part of
the cemented provisional in STL-2, in
other words the contact points,
subgingival area and internal area are
omitted as these features are not visible
in either STL files and so are of no use
for purposes of superimposition.
Again color mapping is used to check
the precision of the superimposition as
in the previous alignment
21. 6 STL Files
STL Files
1+2+3
virtual gingiva
STL Files
4+5+6
prosthetic
crown
When a sagittal cross-section of the three aligned scans is examined,
the third file shows the collapsed gingiva; when the provisional was
removed this caused the gingiva to move centripetally inwards to- wards
the tooth, filling the space formerly occupied by the provisional.
To avoid this collapse and obtain a gingival position identical to that
achieved when the provisional was in place, a virtual gingiva is created,
erasing the collapsed gingiva to create gingival morphology adapted to
the provisional crown’s cervical emergence
22. BOOLEAN OPERATION TO
GENERATE VIRTUAL GINGIVA
Creates an object through a mathematical operation, in which two
objects can remain, intersect or unite to form a new object.
In the present technique, the software’s ’remain’ tool is used.
To do this it is necessary to reproduce the most apical contour of the
provisional crown, so STL-2 must be as precise as possible; as in
STL-1, the most apical portion of the provisional is not visible as it is
positioned subgingivally.
The Boolean operation generates a new master model with an open
gingival sulcus
which can then be exported in the software’s STL format to CAD
software in such a way that the definitive crown can follow the
gingival anatomy created by the provisional
23.
24. CAD-CAM software designed for fabricating dental restorations is used to fabricate
a metal-free crown (made of lithium disilicate, monolithic zirconia, or resin nano-
ceramic) using completely digital techniques and maintaining the exact morphology
of the provisional prosthesis used to generate the biocopy
ensures that the definitive crown is adapted to periodontal tissue on all aspects
(vestibular, lingual and palatal) in exactly the same way as the provisional. Whenever
this non-metallic crown design protocol is used is it advisable to mill a test sample
from transparent resin to check restoration-preparation fit, evaluate dental
size,dental morphology, contact points, and occlusion
25. it is important to ensure by frontal and occlusal visual examination
that the prosthetic emergence does not provoke ischemia at any point
in the gingival sulcus
26.
27. DISCUSSION
In the technique described here, the provisional crown plays an
important role, providing registers of the soft tissue response and
emergence profile, which are later reproduced exactly in the final
restoration
The difference between the emergence created by the provisional and
the collapsed gingiva once the provisional has been removed, even
though it may be minimal, does affect the placement of the definitive
restoration; variation will also increase according to the time the
patient spends without the provisional in place
It is a fast procedure and is easy to apply in cases when the gingiva
does not adapt correctly.
It also makes it possible to create an intrasulcular mock-up with ideal
prosthetic cervical contours and horizontal overcontouring
28. LIMITATIONS OF THIS STUDY
Intraoral scanners demand considerable economic investment and
their correct use constitutes a steep learning curve, and requires
constant updating.
Intraoral scanners obtain good results in terms of prosthetic precision
on a small scale, but this is not the case in full arch restorations.
However, in the case of BOPT, intraoral scanning is an innovative
technique that has not been widely reported in the literature, so
further assessment of soft tissue behavior is needed in the form of
prospective clinical trials with long-term follow-ups.
At the same time, mono- lithic materials milled using CAD-CAM
technology obtain optimal results in terms of strength and fit but may
present limitations, especially regarding esthetics.
They cannot be individualized like analogue restorations that are
manually shaped and crafted by the laboratory technician.
29. CONCLUSIONS
This digital protocol is of great relevance to clinicians, as it makes it
possible to reproduce anatomical dental information, soft tissue
contours, and emergence profiles exactly, without the use of
conventional impression-taking techniques, unaffected by gingival
collapse when the provisional is removed, and exactly transferring the
periodontal morphology around the provisional crown to the
definitive restoration.
30. RELATED ARTICLES
Loi I, Di Felice A. Biologically oriented preparation technique (BOPT): a
new approach for prosthetic restoration of periodontically healthy
teeth. Eur J Esthet Dent. 2013 Mar 1;8(1):10-23.
In this article, the author presents a prosthetic
technique for periodontally healthy teeth using
feather edge preparation in a flap- less approach
in both esthetic and posterior areas with
ceramometal and zirconia restorations, achieving
high quality clinical and esthetic results in terms
of soft tissue stability at the prosthetic/tissue
interface, both in the short and in the long term
(clinical follow-up up to fifteen years).
31.
32.
33.
34.
35.
36. AGUSTÍN-PANADERO R, SERRA-PASTOR B, FONS-FONT A,
SOLÁ-RUÍZ MF. PROSPECTIVE CLINICAL STUDY OF ZIRCONIA
FULL-COVERAGE RESTORATIONS ON TEETH PREPARED WITH
BIOLOGICALLY ORIENTED PREPARATION TECHNIQUE ON
GINGIVAL HEALTH: RESULTS AFTER TWO-YEAR FOLLOW-UP.
OPERATIVE DENTISTRY. 2018 SEP;43(5):482-7.
To evaluate the clinical behavior of
one-piece complete-coverage
crowns and fixed partial dentures
(FPDs) on teeth with vertical
preparation without finish line
biologically oriented preparation
technique (BOPT).
The sample was divided into two
groups: one-piece crowns and FPDs,
all with zirconia cores, feldspathic
ceramic veneer, and a 0.5-mm
prosthetic finish line of zirconia.
Evaluated oral hygiene, periodontal
state, gingival thickening, gingival
margin stability, the presence of
37. Teeth prepared with BOPT and restored with
zirconia crowns or FPDs presented a 100% survival
Technique generates gingival thickening , as well
as gingival margin stability in 100% of samples.
High periodontal tissue and gingival margin stability, provided
the patient
maintains adequate oral hygiene
38. PANIZ, G., NART, J., GOBBATO, L., MAZZOCCO, F., STELLINI,
E., DE SIMONE, G. AND BRESSAN, E., 2017. CLINICAL
PERIODONTAL RESPONSE TO ANTERIOR ALL-CERAMIC
CROWNS WITH EITHER CHAMFER OR FEATHER-EDGE
SUBGINGIVAL TOOTH PREPARATIONS: SIX-MONTH RESULTS
AND PATIENT PERCEPTION. INTERNATIONAL JOURNAL OF
PERIODONTICS & RESTORATIVE DENTISTRY, 37(1).
The purpose of this
prospective randomized
clinical study was to
determine if two different
subgingival margin designs
influence the periodontal
parameters and patient
perception. Deep chamfer
and feather-edge
preparations were compared
on 58 patients with 6 months
follow-up.
40. Statistically significant differences were present for bleeding on probing, gingival recession,
and patient satisfaction. Featheredge preparation was associated with increased bleeding on
probing and deep chamfer with increased recession; improved patient comfort was registered
with chamfer margin design. Subgingival margins are technique sensitive, especially when
feather-edge design is selected. This margin design may facilitate soft tissue stability but can
41. AGUSTÍN-PANADERO R, MARTÍN-DE LLANO JJ, FONS-
FONT A, CARDA C. HISTOLOGICAL STUDY OF HUMAN
PERIODONTAL TISSUE FOLLOWING BIOLOGICALLY
ORIENTED PREPARATION TECHNIQUE (BOPT).
JOURNAL OF CLINICAL AND EXPERIMENTAL
DENTISTRY. 2020 JUN;12(6):E597.Aim of this study was to conduct histological analysis of a human
tooth resected with the periodontal insertion apparatus intact
following treatment using biologically oriented preparation technique
(BOPT)
This descriptive histological dento-periodontal study used an anterior
tooth extracted with the surrounding periodontal tissues intact,
following prosthetic restoration with BOPT.
Eight serial sections of the restored tooth were processed. The
relative location and histological characteristics of the cemented
prosthetic crown, the dental tissues of the tooth prepared by BOPT
technique, and the periodontal tissues were analyzed.
42. RESULTS
Structural analysis of the neoformed junctional epithelium showed
that the number of layers decrease apically until there was a single
row of cells perfectly adhered to the acellular cementum, and beneath
the epithelium a connective tissue evidently free from inflammation.
The tissues of the neoformed periodontium (gingival ligament,
sulcular epithelium, junctional epithelium) presented histologic
normality.
43. PERIS H, GODOY L, COGOLLUDO PG,
FERREIROA A. CERAMIC VENEERS ON CENTRAL
INCISORS WITHOUT FINISH LINE USING BOPT IN
A CASE WITH GINGIVAL ASYMMETRY. JOURNAL
OF CLINICAL AND EXPERIMENTAL DENTISTRY.
2019 JUN;11(6):E577.This clinical case report describes the rehabilitation of central
incisors with veneers in a patient with gingival asymmetry.
The teeth were prepared without finish line, applying BOPT concepts
to correct asymmetry, and obtained a harmoniously integrated
restoration with optimal periodontal health.
44.
45. It is possible to correct gingival asymmetry by
performing dental preparation without finish line
providing
a correct periodontal analysis is first performed, which
will contribute to successful soft tissue stabilization
46. REFERENCES
Loi I, Di Felice A. Biologically oriented preparation technique (BOPT): a new
approach for prosthetic restoration of periodontically healthy teeth. Eur J
Esthet Dent. 2013 Mar 1;8(1):10-23.
Peris H, Godoy L, Cogolludo PG, Ferreiroa A. Ceramic veneers on central
incisors without finish line using bopt in a case with gingival asymmetry.
Journal of clinical and experimental dentistry. 2019 Jun;11(6):e577.
Agustín-Panadero R, Martín-de Llano JJ, Fons-Font A, Carda C. Histological
study of human periodontal tissue following biologically oriented
preparation technique (BOPT). Journal of Clinical and Experimental Dentistry.
2020 Jun;12(6):e597.
Paniz, G., Nart, J., Gobbato, L., Mazzocco, F., Stellini, E., De Simone, G. and
Bressan, E., 2017. Clinical Periodontal Response to Anterior All-Ceramic
Crowns with Either Chamfer or Feather-edge Subgingival Tooth Preparations:
Six-Month Results and Patient Perception. International Journal of
Periodontics & Restorative Dentistry, 37(1).
Agustín-Panadero R, Serra-Pastor B, Fons-Font A, Solá-Ruíz MF. Prospective
clinical study of zirconia full-coverage restorations on teeth prepared with
biologically oriented preparation technique on gingival health: results after
two-year follow-up. Operative dentistry. 2018 Sep;43(5):482-7.
Editor's Notes
The introduction of digital technologies for recording data for the purposes of placing tooth- and implant-supported fixed pros- theses has brought about great improvements in the quality of this type of restoration, in the ease of communication between clinical and laboratory staff, and both patients’ and dentists’ satisfaction with treatment outcomes. Intraoral scanners are becoming increasingly common in den- tal clinics and have streamlined treatment protocols and sequences in the field of prosthodontics. Due to their speed, these tech- nologies are rapidly replacing traditional techniques of impression taking in both implant-based and dental treatments. Nevertheless they still suffer a number of limitations when it comes to re- producing dental preparations with subgingival finish lines
producing gingival emergence profiles without gingival collapse in apically positioned implants, in complete tooth-supported rehabilitation, or when registering complete arches supported by more than six implants. But technology is developing so fast that these drawbacks will surely be overcome in the near future
With BOPT, overcontouring is entirely different from that which constitutes cervical overcontouring over a horizontal finishing line. We must distinguish between what is defined as the anatomi- cal crown and what is described as a tooth’s clinical crown [5–8] . With BOPT the convexity of the anatomical crown is modified, so that the prosthesis imitates the natural tooth, from which any horizontal-convex component above the cemento-enamel junction has been eliminated previously. But with a horizontal finishing line, the emergence of the tooth’s clinical crown is modified; this is where the well-known periodontal problems described in the liter- ature arise [9] , as the horizontal finishing line favors the accumu- lation of dental plaque resulting from aberrant anatomy. It must be understood that with BOPT, the procedure imitates the convex anatomy of the natural tooth above its CEJ
Patient is anesthetized and a calibrated periodontal probe is inserted in the sulcus parallel to the tooth’s axis until it reaches the bone crest.
periodontal examination must be performed using a , ensuring that the case is free of any peri- odontal pathology. To do this, the
(under normal conditions this is situated 1 mm apical of the gingival margin and 2 mm coronal of the alveolar crest)-
; the bur interacts with the tooth surface and the epithelial element of gingival insertion (as far as the cemento-enamel junction) performing
Intra sulcular area of the provisional restoration supports the gingival margin circumferentially. The healing process then produces reinsertion and gingival tissue thickening, which will adapt to the new emergence profile.
To obtain good provisional prosthesis adaptation on vertical tooth preparations, the prosthesis must be fabricated before dental preparation is performed.
Classic analogue impression technique for BOPT and gingival sulcus morphology - two-stage wash technique with double-cord retraction.
In addition, due to the de-insertion of the provisional prosthesis and the placement of two retraction cords, there is a risk of altering the real position of the gingival margin and sulcular anatomypossibility of gingival tissue collapse, which will cause error when it comes to registering the intrasulcular area
.
; the entire procedure follows a chairside protocol with the following clinical sequence: 2.3.1
The STL files generated from these scans have not been included
in the present article as they do not represent any innovation in the clinical procedure described. 2.3.5
, as this figure shows the superimposition quality of STL-1 and STL-3, whereby in
The term digital biocopy refers to the ideal morphology of the defini- tive prosthesis based on a duplicate of the provisional pros- thesis, which has been seen to present healthy periodontal conditions around its cervical anatomy. In this way, the tech- nique
In a case requiring slight modification of the resin crown’s anatomy in order to adapt it to the conditions in the oral medium (adding composite resin material or elimi- nating material with a tungsten carbide bur) this can be performed using this transparent sample. Afterwards, the modi- fied crown is scanned with the intraoral scanner and the STL
file obtained is sent to the laboratory to carry out best-fit with the virtual design of the previous prosthodontic work; when all parameters have been checked for accuracy, the definitive restoration can be machined. In this way, it can be ensured that the definitive crown anatomy remains un- changed and is not manipulated when it is placed on the tooth
Digital technologies continue to suffer certain limitations in comparison with conventional techniques, such as the difficulty of detecting subgingival finish lines, recording gingival emergence in deep implants, or rehabilitating a complete arch. They also require changes in working protocols that involve a learning curve and fa- miliarization with the techniques involved as the use of scanners to obtain a digital impression must be performed by an experienced professional. In addition, there is the considerable economic investment in equipment required to introduce them into clinical practice [1–3] . Research continues into how best to establish completely dig- italized workflows that obtain complete data about teeth and im- plants, as well as the surrounding soft tissues, the subgingival area, and the dentogingival sulcus
3] . Intraoral scanners suffer one particular drawback: when the provisional crown is re- moved, a collapse of the gingiva is produced making it impossi- ble to reproduce this area precisely. For this reason, the technique described in this article offers a digital protocol capable of over- coming this problem, a drawback that does not apply to conven- tional impression taking techniques [4,10 .
The use of digital workflows in dentistry is fast becoming estab- lished. Nevertheless
prospective study
included 52 patients requiring treatment with
restorations in the esthetic region: 74 crowns
and 27 FPDs. The sample included a total of
149 teeth that were prepared vertically without finish line. The sample was divided into
two groups: one-piece crowns and FPDs, all
with zirconia cores, feldspathic ceramic veneer, and a 0.5-mm prosthetic finish line of
zirconia. All procedures were carried out at
the University of Valencia from 2013 to 2014.
The following parameters were evaluated over
a two-year follow-up: oral hygiene, periodontal
state, gingival thickening, gingival margin
stability, the presence of complications, and
restoration survival rate. Patient satisfact