Dental Classes III Flashcards

Study Notes

Class III Overview

Class III caries involve smooth surface lesions on proximal areas of incisors and canines.
Initial lesions appear V-shaped and develop laterally at the dentin-enamel junction (DEJ).
Detection methods include radiography, visual inspection, and transillumination.

Class III Preparation

Classic preparation extends 0.5mm into dentin; modifications may allow enamel-only finishing in some cases.
Maintaining the integrity of the incisal edge is crucial to prevent fractures.
Preparation shape might be influenced by proximity to the incisal edge.

Class III Composite Preparations

Steps in cavity preparation include: outline form, resistance form, retention form, removing decay, pulp protection, finishing the cavosurface, and ensuring cleanliness.

Outline Form

Represents the outer shape of the cavity and includes decay removal.
Cavity margins must connect with healthy tooth structure, maintaining contact with adjacent teeth at the gingival margin.

Initial Entry Technique

Utilize a #330 bur positioned perpendicular to the lingual surface and make entry gingival to the contact area.

Resistance and Retention Forms

Resistance form prevents fractures through internal shape; the axial wall resides in dentin at 0.5mm depth.
Retention form holds fillings in place using acid-etching without requiring undercuts.

Margination Techniques

Cavosurface margins should meet at 90 degrees without bevels for optimal strength and esthetics.

Class V Lesions Overview

Class V lesions can arise from caries, abrasions, erosions, or abfractions, typically affecting the cervical third of the tooth.
Outline forms correlate with tooth diameter and follow the contour of the cementoenamel junction (CEJ).

Erosion and Abrasion

Abrasion often results from hard toothbrushes and abrasive pastes; its clinical manifestation is a well-defined V-shaped notch.
Erosion is a chemical process leading to smooth, dish-shaped loss of tooth structure, commonly from acidic foods.

Abfraction

Caused by flexure forces leading to micro-fractures at the tooth neck, often seen in bruxers, presenting as V or wedge-shaped defects.

Clinical Management

Potential surgical intervention for non-carious lesions involving teeth sensitivity; esthetics can also be a significant factor.
Carious lesion detection involves assessing soft or leathery textures for active lesions versus hard, shiny textures for inactive lesions.

Class V Preparations

Preparations are determined by the extent of caries, often requiring no classic form for non-carious abrasions or erosions.
Amalgam preparations require retention grooves in dentin, while composites necessitate beveled enamel margins.

Choosing Restorative Materials

Consider isolation capabilities, esthetic requirements, and moisture control for material selection. Moisture cannot be managed, composites are unsuitable.

Protection of Pulp

Amalgam utilizes Resin Modified Glass Ionomer (RMGI) for pulp protection; composites involve etching and bonding agents to maintain vitality.

Tooth Fracture Classification

Classifications include uncomplicated and complicated fractures based on the involvement of enamel, dentin, and pulp.
Crowns can sustain fractures in varying degrees, classified into classes I (enamel only) to IV (complete crown loss).

Rubber Dam Isolation

For tooth #20, quadrant rubber dam isolation should extend from tooth #18 to #25 for effective moisture control.

Important Points About Caries and Class IV

Caries genesis involves bacterial acid production leading to demineralization.
Class IV causes include caries, trauma, and anatomical defects, warranting proper management in restorative dentistry.

Finishing Techniques

Finishing involves the use of sequential disks, finishing burs, and sandpaper strips to achieve a smooth restoration surface.

Description

This quiz features flashcards focusing on Class III cavities and preparations. It encompasses definitions, characteristics, and methods for detecting these types of caries. Ideal for dental students seeking to reinforce their understanding of restorative dentistry.