The document discusses the fundamentals of cavity preparation, including its definition, objectives, and historical development. It covers factors that affect cavity preparation as well as terminology, classification, and the stages of initial and final tooth preparation. The key principles of cavity preparation are to remove all defective tooth structure, protect the pulp, and provide retention for the restorative material. Modern cavity preparation techniques favor prevention of extension and minimal intervention.
this contains the steps for the class 1 cavity preparation for amalgam in detail. also contains the difference between composite and amalgam cavity preparation.
Fundamentals in tooth preparation, Now many indications for treatment for teeth are not due to caries and, therefore, the preparation of the tooth is no longer referred to as cavity preparation but as tooth preparation, and the term cavity is used only as a historical reference.
NOMENCLATURE
this contains the steps for the class 1 cavity preparation for amalgam in detail. also contains the difference between composite and amalgam cavity preparation.
Fundamentals in tooth preparation, Now many indications for treatment for teeth are not due to caries and, therefore, the preparation of the tooth is no longer referred to as cavity preparation but as tooth preparation, and the term cavity is used only as a historical reference.
NOMENCLATURE
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.
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.
Teeth don’t possess regenerative ability found in most other tissues. Therefore, once enamel & dentin are lost as a result of caries, trauma or wear, restorative material must be used, to reestablish form & function.
Teeth require preparation to receive restoration & these preparations must be based on fundamental principles, which are discussed in this presentation, from which basic criteria can be developed to help predict the success of prosthodontic treatment.
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.
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.
Teeth don’t possess regenerative ability found in most other tissues. Therefore, once enamel & dentin are lost as a result of caries, trauma or wear, restorative material must be used, to reestablish form & function.
Teeth require preparation to receive restoration & these preparations must be based on fundamental principles, which are discussed in this presentation, from which basic criteria can be developed to help predict the success of prosthodontic treatment.
Strip Crowns Technique for Restoration of Primary Anterior Teeth: Case ReportAbu-Hussein Muhamad
Dental caries is the single most common chronic childhood disease affecting worldwide. In early childhood caries, there is early pulp involvement and gross destruction of maxillary anterior teeth as well as posterior teeth. Treatment of such caries represents a challenge to pediatric dentists especially, when teeth are badly destroyed. By the time the dentist sees the child, most of the coronal structure is lost. This case report describes challenging task of a Case of early childhood caries patients with mutilated maxillary incisors restored with a strip form composite restorations.
This is the powerpoint presentation for Principles of Cavity preparation in the undergraduate level. It includes all the basic details a budding dentist has to know in the department of conservative dentistry. Hope you would learn better and enjoy learning.
The potentiality of dental professional/ endodontists to carry out routine procedures successfully relies chiefly on the adequacy of local anaesthesia achieved. However, local anaesthetics (including lidocaine, the most commonly used local anaesthetic) have a tendency to cause pain on mucosal infiltration, which adds to patient anxiety during procedures.1 In fact, investigators have reported a more painful skin and subcutaneous infiltration with an epinephrine-containing lidocaine.2
The most probable mechanism of this pain is attributed to the reduced pH of an epinephrine-containing lidocaine compared to a plain lidocaine solution. A weakly basic amide, lidocaine being unstable at pH of 7.9, is made in acidic preparations to to enhance the solubility and prolong shelf life. Moreover, epinephrine is added to lidocaine to extend the half-life of the anesthetic, lessen toxicity, and provide hemostasis. Because epinephrine is only stable for lengthy phases in an acidic environment, the pH of commercially available premixed lidocaine with epinephrine is lower than that of plain lidocaine (pH 3.3-5.5) and the acidity can give rise to tissue irritation which may be felt by patients as a stinging or burning pain. 3,4
Based on the attributed mechanism, most common method for buffering is the alkalinisation of the lidocaine with sodium bicarbonate just before injection. Buffering with sodium bicarbonate (NaHCO3) 8.4%in a 10:1 or 9:1 ratio (10 or 9 parts lidocaine-epinephrine 1% containing 5 microgram/ml to 1 part sodium bicarbonate containing 8.4g/l) more closely matches the neutral pH (around 7.4) in human tissues and has been demonstrated to cause less CDJIpain than unbuffered lidocaine.1, 5-13
Body dysmorphic disorder (BDD), also known as body dysmorphia, body dysmorphia disorder and BDD disorder, is a mental health condition in which people suffer acute distress in response to perceived physical flaws.
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
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.
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
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.
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
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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.
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2. CONTENTS
INTRODUCTION
DEFINITION
NEED FOR RESTORATIONS
OBJECTIVES OF CAVITY PREPARATION
HISTORICAL DEVELOPMENT
FUNDAMENTALS OF CAVITY PREPARATION
FACTORS AFFECTING CAVITY PREPARATION
TOOTH PREPARATION TERMINOLOGY
CLASSIFICATION OF TOOTH PREPARATION
INITIAL TOOTH PREPARATION STAGE
o Outline Form And Initial Depth
o Primary Resistance Form
o Primary Retention Form
o Convenience Form
FINAL TOOTH PREPARATION STAGE
o Removal Of Any Remaining
o Infected Dentin /Old Restorative Material
o Pulp Protection
o Secondary Resistance And Retention Forms
o Procedures For Finishing
External Walls
o Cleaning, Inspecting, Sealing
ADDITIONAL CONCEPTS IN TOOTH PREPARATION
o Amalgam Restorations
o Complete Restorations
CONCLUSION
REFERENCES
3. Success is neither magical nor mysterious…
Success is the natural consequence of
consistently applying the basic fundamentals.
JIM ROHN
“
”
5. • In the past, most restorative treatment was due to caries
(decay)
• ‘Cavity’ was used to describe a carious lesion in a tooth that
had progressed to the point that part of the tooth structure
had been destroyed.
• Tooth was cavitated ; referred to as a cavity.
• Affected tooth was repaired; cutting or preparation of
remaining tooth was referred to as a cavity preparation.
• Now many indications for treatment for teeth are not due to
caries.
• Preparation of the tooth is no longer referred to as cavity
preparation but as tooth preparation.
• Term cavity used as a historical reference.
Roberson T. Sturdevant's Art And Science Of Operative Dentistry ( Fifth Edition). St. Louis : Mosby Elsevier; 2006.
6. “
Tooth preparation is the mechanical
alteration of a defective, injured, or
diseased tooth to receive a restorative
material that re-establishes a
healthy state for the tooth including
esthetic corrections, where indicated.
DEFINITION
~Sturdevant
“
Roberson T. Sturdevant's Art And Science Of Operative Dentistry ( Fifth Edition). St. Louis : Mosby Elsevier; 2006.
7. Need For The Restoration
1. Repair of tooth after destruction from carious lesions.
2. Replacement / repair of restorations with serious defects such as improper
proximal contacts, gingival excess, poor esthetics etc.
3. Restoration of proper form and function of fractured teeth.
4. Restoration of form and function as a result of congenital malformations
5. To fulfill the esthetic demands
6. Restoration for preventive measures
Roberson T. Sturdevant's Art And Science Of Operative Dentistry ( Fifth Edition). St. Louis : Mosby Elsevier; 2006.
8. Objectives of tooth preparation
1. Removes all defects and provides necessary protection to the pulp.
2. Extension of the margins of restoration as conservatively as possible
3. Cavity is formed such that under forces of mastication, the tooth or
restoration, or both will not fracture and restoration will not be displaced
4. Allows for aesthetic and functional placement of a restorative material
Roberson T. Sturdevant's Art And Science Of Operative Dentistry ( Fifth Edition). St. Louis : Mosby Elsevier; 2006.
10. WEBB
1883
• First published work
• Mentioned in his textbook:
• “Every cavity must be so prepared that no
decalcified tissue remains, except where
there be a little discoloured dentine near
pulp, and that should be left for its
protection”.
• “Prevention of extension of decay” :
supported the extension of preparation into
the contact-free “self-cleansing” areas to avoid
food accumulation especially on proximal
surface
Webb MH (1883) Notes on Operative Dentistry. S.S. White Manufacturing Co., Philadelphia. 72-88.
11. GV Black
1891
“EXTENSION
FOR
PREVENTION”
“In no case should any decayed and softened
material be left. It is better to expose the pulp of
the tooth than leave it covered only with softened
dentine”
Removal of all infected, affected dentine.
Healthy tooth structure can be removed for
better access and visibility
Extension of preparation in adjacent pits and
fissures for prevention
Should have definite mechanical retention in the
restoration
+ Self-cleansing area –prevents recurrence of decay
in tooth surface adjoining restoration
Black GV (1891) The managment of enamel margins. Dental Cosmos 33 :85-100.
12.
13. Slagle
1904
“EXTENSION FOR
RETENTION”
• Focused more on “anchorage” or retention of
restorative material inside prepared cavities after
careful evaluation of occlusal forces.
• Introduced some secondary features to cavity
preparation for increasing the retention of
restorative materials (e.g. grooves, locks, coves).
Slagle CE (1904) The Fundamental Principles of Extension in Approximal Cavities in Bicuspids and Molars. Dental Cosmos 46: 443-445.
14. 1928
PRIME
CONCEPT
Adapt the filling material to the tooth.
Achieve a proximal triangular form.
Achieve 'independent surface retention
Extension for prevention - not necessary
Prime, J.M. A plea for conservatism in operative procedures. JADA 15(1}:1234-1246,1928
15. Bronner
1931
• Proximal outline forms should converge
• Gingival wall should be inclined axially to
• prevent dislodgment in a proximal direction.
• With the proximal box thus becoming a “
self-locking device- occlusal dovetail obviated.
• Discussed the management of a weakened
cusp by a procedure called “onfilling”
”Shoeing a cusp ” with amalgam.
Bronner, F.J. Engineering principles applied to class II cavities. J Dent Res 10:115-119,1930.
16. Markley
1951
• Narrow occlusal preparation with slightly
convergent walls following direction of
enamel rods.
• Proximal preparation- narrow across the
marginal ridge
• Recommended proximal retentive grooves so
that each portion of restoration could be self-
retentive .
Markley, M.R. Restorations of silver amalgam.JADA 43(2):133-146,1951
17. 1956
1959
VALE
EXPERIMENTS
• Two important features recognised in
conservative preparation.
• Concluded:
reduction of occlusal width from a third to
fourth the intercuspal distance- greater
strength in the prepared tooth.
Rounding of internal angle -better adaptation
of amalgam.
Vale, W.A. Cavity preparation. Irish Dent Rev 2:33-41,1956.
Vale, W.A. Cavity preparation and further thoughts on high speed. Br Dent J 107:333-340,1959.
18. 1958
Mahler & Peyton
• Slightly round the axiopulpal line angle to
increase amalgam bulk in that area; decrease
the internal stress.
• Decrease width of isthmus,depth of isthmus,
depth of preparation to decrease the internal
stress within the tooth.- increases the resistance
of tooth structure to deformation and failure
• Rounded pulpal floor more suitable than a
plane.
• Occlusal convergence should be minimal so
that the restoration may receive the maximum
support of the cavity walls.
Mahler, D.B. An analysis o f stresses in a dental amalgam restoration. J Dent Res 37(3):516-525,1958.
19. 1964
Gilmore
For the modern preparation:
isthmus width:
1 mm or less for first premolars
1.5 mm or less for molars
depth of 0.5 mm into dentin .
Mahler, D.B., and Peyton, F.A. Photoelasticity as a research technique for analyzing stresses in dental structures. J
Dent Res 34(6):831-838,1955.
20. 1975
Galan
Deformation in proximal portion of the
Class II restoration could be decreased by
locating retention grooves above the axio-
pulpal line angle.”
Galan, J.; Gilmore, H.W.; and Lund, M.R. Retention for the proximal portion of the Class n amalgam restoration. J
Ind Dent Assoc 54(6):16-19,1975
21. 1998
SUMMILT
AND
OSBORNE CONCEPT
• Do not extend for prevention in class I
preparations - only prepare in areas of
diagnosed caries.
• Keep preparation as narrow as caries
allows.
• Do not extend class 2 preparations into
occlusal grooves, if occlusal surface is not
involved by caries at all
• If occlusal extension is less than 1.2 mm
wide, augment retention of proximal box
with retention locks on facial/lingual walls.
Osborne JW, Summitt JB. Extension for prevention: is it relevant today? Am J Dent. 1998 Aug;11(4):189-96.
22. 20th
Century
“PREVENTION OF
EXTENSION”
• “Minimally Invasive Dentistry”
• Aim- achieve as much conservation of dental tissue as
possible.
• Includes :
early detection of dental caries
assessment and management of caries-risk,
remineralisation of early caries lesions,
only restoring cavitated lesions
restriction of excavation to the caries-infected
areas
using adhesive-based technologies
• Retentive features changed from macromechanical to
micro-mechanical (resin adhesives) and chemical (e.g.
resin-modified glass ionomer adhesives) retention.
Ericson D (2007) The concept of minimally invasive dentistry. Dent Update 34(1): 9-10.
Frencken JE, Peters MC, Manton DJ, Leal SC, Gordan VV, et al. (2012) Minimal intervention dentistry for managing dental caries - a review: report of a FDI task group. Int Dent J 62(5): 223-243
23. CURRENT
PERSPECTIVES
Prevention of extension or as Sigurjons
states, constriction with conviction -
operative phrases in modern cavity
preparation
Increased knowledge of:
caries progression and prevention
remineralisation of tooth structure
improved amalgam alloys
systemic and topical fluoridation
precision instrumentation
advanced diagnostic aids
better oral hygiene
24. • Basic principles governing the design of cavities and steps in their preparation- first suggested
by American Dentist and teacher Dr. G.V .Black in the first decade of the last century.
• He based these principles on what was known at time about the natural history of caries and the
restorative material available.
• The wisdom of his work was such that it remained unchallenged for more than half a century
• But now with new materials, a better understanding of caries and research findings into the
success of various restorative procedure, his principles have been largely revised.
• Modification and rearrangement of these original principles have been largely revised.
25. • Concepts professed by Bronner, Markley, J Sturdevant, Sockwell, and C Sturdevant.
• Improvements in restorative materials, instruments, and techniques.
• Increased knowledge and application of preventive measures for caries.
Roberson T. Sturdevant's Art And Science Of Operative Dentistry ( Fifth Edition). St. Louis : Mosby Elsevier; 2006.
26. FUNDAMENTALS OF TOOTH PREPARATION
1. No friable tooth structure can be left.
2. Fault, defect, or caries is removed.
3. Remaining tooth structure is left as strong as possible.
4. Underlying pulpal tissue is protected.
5. Restorative material is retained in a strong, esthetic (in some
cases), and functional manner.
27. TYPE
Conventional
Preparation
Modified
Preparation
Reduced degree of precision
May require only removal of defect (caries,
fracture, or defective restorative material)
and friable tooth structure without specific
uniform depths, wall designs, retentive
features or marginal forms.
Adhesive restorations, primarily composites,
glass ionomers
Precise procedures resulting in uniform
depths, particular wall forms, and specific
marginal configurations.
Require specific wall forms, depths, and
marginal forms
Amalgam, cast metal, and ceramic
restorations preparations
29. GENERAL
• DIAGNOSIS
• Assessment of pulpal, periodontal status of tooth
• Assessment of occlusal relationships.
• Deciduous/ permanent tooth.
• Type, location of tooth.
• Type of anomaly
• Knowledge of Dental Anatomy
• Direction of enamel rods
• Thickness of enamel,dentin
• Size and position of pulp
• Relationship of tooth to supporting tissues
PATIENT
• Age
• Concern for aesthetics
• Economic status
• Xerostomia
• Diet
• Caries index
• General health.
• Parafunctional habits
• Supplementary intake of fluorides
30. TOOTH
• To conserve the tooth structure.
• To repair the damage from dental
caries and prove the vitality of the
tooth
• Restorations should be as small as
possible
• Lesser the tooth structure removed,
lesser the chance for pulpal damage
RESTORATIVE MATERIAL
• Type
• Physical properties of restoration
• Moisture control
• Extensiveness of problem
33. Abbreviated Descriptions of Tooth Preparations
an occlusal tooth preparation = O
a preparation involving - mesial and occlusal surfaces = MO
a preparation involving the mesial, occlusal, and distal surfaces = MOD
Description of a tooth preparation is abbreviated by using the first
letter, capitalized, of each tooth surface involved
34. COMPONENTS OF A CAVITY PREPARATION
COMPONENTS
CAVITY WALL CAVITY
PREPARATION
ANGLE
Additional
36. INTERNAL WALL
An internal wall is a prepared (cut) surface that does
not extend to the external tooth surface
An axial wall is an internal wall parallel
with the long axis of the tooth.
A pulpal wall is an internal wall that is
perpendicular to the long axis of the
tooth and occlusal of the pulp
37. EXTERNAL WALL
An external wall is a prepared (cut) surface
that extends to the external tooth surface
38. FLOOR (OR SEAT)
A floor is a prepared (cut) wall that is reasonably flat
and perpendicular to the occlusal forces that are
directed occlusogingivally (generally parallel to the long
axis of the tooth).
39. ENAMEL/DENTIN WALL
The enamel wall is that portion of a prepared external
wall consisting of enamel
The dentinal wall is that portion of a prepared external wall consisting of
dentin, in which mechanical retention features may be located
40. CAVITY PREPARATION
ANGLE
A line angle is the junction of two planal
surfaces of different orientation along a line
A point angle is the junction of three planal
surfaces of different orientation
45. CAVOSURFACE ANGLE
The cavosurface angle is the angle of tooth
structure formed by the junction of a
prepared (cut) wall and the external surface
of the tooth
55. • Placing the preparation margins in the position they will occupy in
the final tooth preparation except for finishing enamel walls and
margins
• Maintaining the initial depth of 0.2 to 0.8 mm into the dentin.
• Outline form defines the external boundaries of the preparations.
1. OUTLINE FORM AND INITIAL DEPTH
56. For extension for prevention:
Advantages
• Prevents recurrence of decay in the tooth surface adjoining
restoration
• Results in self-cleaning embrasure areas
• Margins of the restoration are placed on line angles of the tooth
• Occlusal surface is extended through pits and fissures
• Proximal line angles extended buccally and lingually through embrasures and
cervically below the gingival margin
57. Principles Features for Establishing A Proper Outline form
• Removal of all weakened and friable
tooth structure
• Removal of all undermined enamel
• Incorporate all faults in preparation
• Place all margins of preparation in a
position to afford good finishing of the
restoration.
• Preserving cuspal strength
• Preserving strength of marginal ridge
• Minimizing the buccolingual extensions
• If distance between two faults is less than
0.5 mm, connect them
• Limiting the depth of preparation 0.2 to 0.8
mm into dentin
• Using enameloplasty wherever indicated
58.
59. Outline form for Smooth Surface Lesions—Outline form
of Proximal Caries (Class II, III and IV lesions)
• Extend the preparation margins until sound tooth structure is reached
• Restrict the depth of axial wall 0.2 to 0.8 mm into dentin
• Axial wall should be parallel to external surface of the tooth
• In class II tooth preparation, place gingival seat apical to the contact but occlusal to
gingival margin and have the clearance of 0.5 mm from the adjacent tooth
60.
61. Rules for Class V Cavities
• Outline form is limited by extent of the lesion.
• Extensions are made mesially, distally, occlusally and gingivally till sound tooth structure is reached.
• Axial depth is limited to 0.8–1.25 mm pulpally
62. Primary resistance form is that shape and placement of preparation
walls to best enable both the tooth and restoration to withstand,
without fracture, the stresses of masticatory forces delivered
principally along the long axis of the tooth.
2. Primary resistance form
63. Features of Resistance Form
• Box-shaped preparation with flat pulpal and gingival floor
• Adequate thickness of restorative material
• In case of class IV preparations, check the faciolingual width of anterior teeth, to establish
the resistance form.
• Restrict the extension of external walls
• Inclusion of weakened tooth structure
• Rounding of internal line angle
• Consideration to cusp capping depending upon the amount of remaining tooth
structure.
64.
65. 3. Primary Retention Form
Primary retention form is that form, shape and configuration of the
tooth preparation that resists the displacement or removal of
restoration from the preparation under lifting and tipping
masticatory forces.
66. Features
Amalgam
Providing occlusal convergence (about 2°–5°) of dentinal
walls towards the tooth surface
Giving slight undercut in dentin near pulpal wall
Conserving the marginal ridges
Providing occlusal dovetail
67. Features
CAST METALS
• Close parallelism of the opposing walls with slight
occlusal divergence of 2°–5°
• Making occlusal dovetail to prevent tilting of
restoration in class II preparations
• Use of secondary retention in the form of coves,
skirts and dentin slot
• Give reverse bevel in class I compound, class II, and
MOD preparations to prevent tipping movements
68. Features
COMPOSITES:
– Micromechanical bonding between the etched and
primed prepared tooth structure and the composite resin
– Providing enamel bevels.
DIRECT FILLING GOLD:
Elastic compression of dentin and starting point in dentin
provide retention in direct gold fillings by proper
condensation.
69.
70. 4. Convenience Form
The convenience form is that form which facilitates and
provides adequate visibility, accessibility and ease of
operation during preparation and restoration of the tooth.
71. Features
• Sufficient extension of distal, mesial, facial or lingual walls to gain adequate
access to the deeper portion of the preparation.
• Cavosurface margin of the preparation should be related to the selected
restorative material
for the purpose of convenience and marginal adaptation.
• Class II preparations:
Access is made through occlusal surface for convenience form.
Proximal clearance provided from adjoining tooth
Tunnel preparation: proximal caries in posterior teeth is approached
through a tunnel initiating from occlusal surface and ending on carious
lesion on proximal surface without cutting marginal ridge.
Cast gold restorations: occlusal divergence
72. 5. Removal of Any Remaining Enamel Pit or Fissure,
Infected Dentin and/or Old Restorative Material, if
Indicated
• If a small amount of carious lesion remains, only this lesion
should be removed, leaving concave, rounded area in the wall.
• Use low speed handpiece with the round bur or spoon
excavator with light force and a wiping motion.
• Start removal of caries from the lateral borders of the lesion.
• Remove only infected dentin, not the affected dentin
73. 6. Pulp Protection
Pulp protection is achieved using liners, varnishes and bases depending
upon:
• The amount of remaining dentin thickness
• Type of the restorative material used
Liners and varnishes are used where preparation depth is shallow and
remaining dentin thickness is more than 2 mm.
They provide:
• Barrier to protect remaining dentin and pulp
• Galvanic and thermal insulation.
77. 8. Procedures for Finishing the External Walls of
Tooth Preparation
Finishing of a tooth preparation walls is further development of a
specific cavosurface design and degree of smoothness which
produces maximum effectiveness of the restorative material being
used.
• Better marginal seal between restoration and tooth structure
• Increased strength of both tooth structure and restoration at
and near the margins
• Strong location of the margins
• Increase in degree of smoothness of the margins.
78. 9. Final Procedures: Cleaning, Inspecting and
Sealing
Final step in tooth preparation is cleansing of the preparation.
This includes the removal of debris, drying of the preparation,
and final inspection before placing restorative materials
Degree of smoothness of walls
Location of the margins
79. NEWER ADVANCES
Minimally invasive cavity preparations:
1. Tunnel preparation
2. Box only/ slot preparation
Minimally invasive methods of cavity preparations
1. Fissurotomy
2. Use of Polymer burs
3. Air abrasion
4. LASERS
80. CONCLUSION
Tooth preparation is determined by many factors, and each time a tooth is to be restored, each
of these factors must be assessed.
If the principles of tooth preparation are followed, the success of any restoration is greatly
increased.
The increasing bond strengths of enamel and dentin bonding are likely to result in significant
emphasis on adhesive restorations. Likewise, the improved ability to bond to tooth structure is
likely to continue to alter the entire tooth preparation procedure.
When materials can be bonded effectively to a tooth while restoring the inherent strength of
the tooth, the need for refined tooth preparations is reduced or eliminated.
Emphasis shifts away from traditional tooth preparation to knowledge of restorative
materials and dental anatomy.
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