Questions and Answers
What happens when enamel starts to decalcify?
It starts to look chalky.
Axial Wall is ___ to the Long Axis of the Tooth.
parallel
Pulpal Floor or Wall is __ to the Long Axis of the Tooth.
perpendicular
What are line angles?
Signup and view all the answers
What is a point angle?
Signup and view all the answers
How are surfaces classified in dental caries?
Signup and view all the answers
What classification does GV Black use for dental caries?
Signup and view all the answers
Classes II-VI are smooth surface caries.
Signup and view all the answers
What is interproximal?
Signup and view all the answers
The pulpal wall is __ to the long axis of the tooth.
Signup and view all the answers
The axial wall is __ to the long axis of the tooth.
Signup and view all the answers
What must be done during a Class II preparation?
Signup and view all the answers
What is the function of a matrix retainer?
Signup and view all the answers
What are the steps for Class II amalgam preparations?
Signup and view all the answers
What is the outline form?
Signup and view all the answers
Facial and lingual walls being parallel or slightly acute is __.
Signup and view all the answers
What is the importance of breaking contact during cavity preparation?
Signup and view all the answers
Which of the following tooth preparation methods does NYU currently teach?
Signup and view all the answers
What is caries?
Signup and view all the answers
The objectives of tooth preparation include removing defects and protecting the ___.
Signup and view all the answers
What are the nine steps in cavity preparation?
Signup and view all the answers
How many steps did cavity preparation used to have?
Signup and view all the answers
Which classes of tooth caries are classified under GV Black?
Signup and view all the answers
What is the definition of Class I caries?
Signup and view all the answers
What is the primary resistance form in tooth preparation?
Signup and view all the answers
What are the rules for the outline form of a Class I prep?
Signup and view all the answers
What is the function of an amalgam condenser?
Signup and view all the answers
What is the proper cavosurface finish in tooth preparation for amalgam restorations?
Signup and view all the answers
What is debridement of the preparation?
Signup and view all the answers
What instruments are needed for starting preparations?
Signup and view all the answers
What happens when enamel starts to decalcify?
Signup and view all the answers
Study Notes
Basic Operative Dentistry Tooth Preparations
- NYU teaches Modified Classic and Contemporary Preparations only, moving away from classic G.V. Black styles.
- G.V. Black is recognized as the father of modern dentistry; his methods are the foundation of current practices.
- Modified Classic Preparations are smaller than traditional methods and focus on less invasive techniques.
- Contemporary Preparations involve creating holes which are then filled, emphasizing minimal alteration to the tooth structure.
Caries and Treatment
- Caries is classified as an infectious disease that can lead to cavities.
- Surgical preparation is necessary to reduce microorganisms, but complete removal is impossible, as treatment involves cutting into live tissues like enamel and dentin.
Objectives of Tooth Preparation
- Four main objectives drive tooth preparation:
- Remove decay and protect the pulp
- Minimize cutting to conserve healthy tooth structure
- Create a strong preparation that withstands chewing forces
- Allow for proper functional placement of restorations.
Nine Steps in Cavity Preparation
- Steps include Outline Form & Initial Depth, Resistance and Retention Forms, Decay Removal, and Debridement, with Steps 6 and 7 being conditional based on the situation.
Details of Cavity Preparation Steps
- Outline Form & Initial Depth: Outline shape and depth of preparation must establish proper access.
- Primary Resistance Form: Internal design must withstand mastication forces; a well-prepared cavity resists fracture.
- Primary Retention Form: Angles of the walls should ensure the restoration remains in place; facial/lingual walls should be nearly parallel or slightly acute.
- Convenience Form: Adjustments made to access decay beyond ideal prep limits.
- Removal of Decay: Involves using rotary instruments to excavate infected structures, removing the majority of decay but not all.
- Pulp Protection: Necessary if preparation nears the pulp.
- Secondary Resistance & Retention Forms: Techniques used when primary retention is insufficient.
- Cavosurface Finish: Ensures margins are shaped properly to prevent fractures and overhangs, especially for amalgam which requires a 90-degree angle.
- Debridement: Final cleaning step before restoration, removing any debris from the cavity.
Classes of Tooth Caries
- Six classes of caries: Class I through VI, classified under G.V. Black.
Class I Definition
- Class I caries occur primarily in pits and fissures of molars and premolars, as well as the lingual surfaces of anteriors.
- Requires specific measurements for depth, width, and preservation of marginal ridges.
General Guidelines for Class I Preparation
- Maintain 1mm facial-lingual width, 1.7-2mm pulpal depth, and 0.5mm into dentin at shallow points, ensuring smooth walls and proper angles.
Preparation Instruments
- Four essential instruments: Mirror, Explorer (#23), Perioprobe, and College Pliers (Tweezers).
- Use the #23 Explorer for detecting cavities and assessing pulp health.
Handling Decalcification
- Decalcifying enamel appears chalky; probing may lead to confirmed cavities; sealing is recommended at this stage.
Tooth Preparation Walls
- Internal walls (Axial and Pulpal) are oriented differently relative to the long axis of the tooth: axial is parallel, pulpal is perpendicular.
- External walls communicate with the outside of the tooth and include facial, lingual, and mesial/distal walls.
Burrs Used in Preparation
- Common burrs in practice include RA 56 for finishing, 1556 for shaping, and 330 for specific class preparations. The 1556 burr is optimal for depth and angle precision during cavity preparations.### Pulpal Floor and Axial Wall
- Pulpal floor and wall are terms used interchangeably.
- Axial floor and axial wall refer to the same structure.
Line and Point Angles
- Line angle: Intersection of two surfaces, forming a line.
- Point angle: Intersection of three surfaces, forming a point.
Classification by Number of Surfaces
- Simple: Involves one surface (Class I).
- Compound: Involves two surfaces (e.g., occlusal and mesial).
- Complex: Involves three or more surfaces (e.g., MOD).
GV Black Classification of Dental Caries
- Class I: Affects all pits and fissures.
- Class II: Involves proximal surfaces of posterior teeth (premolars and molars).
- Class III: Affects proximal surfaces of anterior teeth (canines, incisors).
- Class IV: Involves proximal surfaces of anterior teeth, including the incisal angle.
- Class V: Affects the gingival third of all teeth, both facially and lingually.
- Class VI: Affects cusp tips of posterior teeth and incisal edges of anterior teeth, with no proximal surface involvement.
Classes II-VI: Caries Types
- Classes II-VI are classified as smooth surface caries.
- Class I represents pit and fissures caries.
Class II Caries Identification
- Class II caries appear on distal surfaces of premolars and molars in X-rays.
Interproximal Definition
- Interproximal refers to the spaces between teeth and is synonymous with proximal.
Class V Characteristics
- Class V affects the gingival third of all teeth on both facial and lingual surfaces.
Class II Preparations
- Pre-wedge all Class II preparations to avoid nicking the adjacent tooth.
- A matrix (Tofflemire) is used in restorations to ensure proper fit.
Class II Amalgam Preparation Steps
- Follow outlined steps: outline form, resistance and retention form, convenience form, removal of decay, pulp protection, margination, and debridement.
Outline Form Rules for Class II Prep
- Maintain marginal ridge integrity, maintain 1mm facio-lingual width, and ensure tapering towards gingivo-occlusal direction.
- Break contacts at the gingival area as this is where decay typically resides.
Light Visibility in Contact Areas
- Light will not be seen if only gingival contact is broken; light is visible only when facial and lingual contacts are also broken.
Divergence in Proximal View
- Diverging walls of Class II prep means facial and lingual walls taper occluso-gingivally while following tooth contours.
Resistance Form Specifications
- Pulpal depth: 1.7-2mm; axial depth 1mm for premolars and 1.3mm for molars.
- Ensure adequate shape to prevent any filling fracture.
Retention Form Specifications
- Facial and lingual walls should ideally be parallel or taper slightly toward the occlusal to avoid falling out.
Unsupported Enamel in Gingival Third
- Unsupported enamel in the gingival third can lead to decay; margination is performed to remove these areas.
Summation of Class I and Class II Box
- Key characteristics include 1mm F-L width, smooth pulpal floor, and specific depths for proper cavity preparation.
Proximal Box Rules
- Ensure convex axial wall, flat gingival floor, and divergent occlusal-gingival walls, maintaining parallelism between B-L walls.
Clarity on Retention and Resistance
- Facial and lingual being parallel/slightly acute relates to retention; all other forms contribute to resistance in preparation.
Orientation to Long Axis of Tooth
- Pulpal wall is perpendicular to the long axis of the tooth.
- Axial wall is also perpendicular to the long axis of the tooth.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the principles of tooth preparation in operative dentistry, focusing on Modified Classic and Contemporary methods. Understand the objectives, challenges, and techniques involved in caries treatment and tooth preservation. Get ready to test your knowledge on these essential dental practices.
