Fundamentals of Cavity Preparation

Protecting the pulp from traumatic, thermal, chemical, and bacterial irritation during cavity preparation.

Avoid unnecessary cutting of enamel, dentin, and depth to prevent weakening the tooth structure. Avoid cutting across pulp chamber lines, and use gentle pressure.

Minimize heat generation during cavity preparation using proper rotary tools and coolant.

Avoid using caustic chemicals or irritants during cavity preparation to prevent pulp damage.

Removing all decayed enamel and dentin, extending cavity margins to susceptible areas, and removing undermined enamel.

Protect the gums from injury during cavity preparation by controlling instrument placement and avoiding irritation.

Steps followed during cavity preparation to preserve the tooth's structure and prevent tensile stresses exceeding material tolerance.

Ensuring cavity margins are free of discolored or pitted enamel for a natural-looking restoration.

External shape of a completed cavity, encompassing the boundaries of the prepared area.

Decayed enamel that must be included in the cavity outline.

Sound dentin supporting the enamel margins; undermined enamel should be removed.

Areas prone to decay due to food stagnation; should be included in the cavity outline.

Small, nearby cavities should be joined into a single preparation to prevent weak spots in the tooth.

Smooth, sweeping curves in the cavity outline help prevent recurrent decay and stress concentration.

Place margins at contact-free areas to minimize stress and prevent fracture.

Cavity outlines should follow the natural pits and fissures; adjust for variations in tooth anatomy.

A basic class I cavity, with buccal-lingual extension of ¼ - ⅓ intercuspal distance and mesio-distal extent beyond the triangular fossa.

Class I cavity extending beyond the pulpal floor, requiring a step-like preparation on buccal/lingual walls.

Cavity confined to a pit without connecting to the occlusal surface; triangular shape.

Class II cavities involve the proximal surfaces of posterior teeth, encompassing the areas between adjacent teeth.

The labial, lingual, and gingival walls of a Class II cavity are extended to the free margins, allowing easier restoration finishing and oral hygiene.

The shape of the narrowest portion of a Class II cavity between the proximal boxes, which follows Ingerham's lines based on contact width.

Guidelines for shaping the isthmus outline of a Class II cavity based on the contact width between teeth.

A type of Class II cavity where the contact area is significantly wide or the adjacent tooth is missing, allowing a straightforward cavity preparation.

A Class II cavity with carious areas only on the proximal surface, while the occlusal surface is unaffected.

A Class II cavity where the proximal caries is prepared on the same level as the pulpal floor, reducing the height difference.

The shape of a prepared cavity that prevents fracture of tooth structure or restoration during mastication.

The shape of a prepared cavity that prevents the restoration from dislodging.

The forces exerted on the teeth during咀嚼.

The width of the isthmus should be slightly wider than the occlusal portion for brittle amalgam restorations.

Preserving healthy tooth structure to prevent weakening and fracture.

The pulpal floor should be flat and smooth for even stress distribution, preventing restoration rotation.

Rounded line angles prevent stress concentration.

Adequate retention for each cavity part increases restoration stability.

The angle between the cavity and the tooth surface, determined by restoration type and enamel rods.

A curve in the buccal wall of the proximal box designed to complete the 90-degree CSA, preventing restoration fracture.

Strong materials that withstand compressive and tensile stresses, and can be finished into thin margins.

Materials sensitive to tensile stress, requiring bulk and a wider CSA for protection.

Form given to the prepared cavity to prevent restoration displacement.

Retention created using chemical reactions, e.g., glass ionomer.

Retention created by using acid etching and bonding (e.g., resin composite).

Retention involving added features in the cavity.

Prevent restoration displacement in an occlusal direction.

Prevent restoration displacement in proximal or lateral directions.

Occlusal convergence of cavity walls, providing retention for direct restorations.

The extension of a cavity preparation on the buccal and lingual surfaces of a molar. This is also known as 'occlusal lock'.

A cavity preparation in Class II cavities that provides lateral retention.

Grooves prepared on the proximal axial line angles of teeth, using tapered fissure burs. They enhance lateral retention and are prepared by sacrificing the buccal/lingual walls.

Small holes and metal pins used for added retention within the tooth structure. Pins can be parallel, non-parallel, vertical, horizontal, threaded, or cemented.

A bevel at the gingival floor of a cavity, particularly in gold inlays. It is a technique to prevent proximal displacement and rotation.

Materials used to permanently bond dental restorations to the tooth structure.

Metal posts placed in root canals for improved retention of restorations, often used in extensive dental work

Flat shelves formed in the dentin floor of a cavity, especially crucial when the pulpal floor is rounded. It helps prevent rotation of the restoration.

A cavity form with parallel or perpendicular walls, flat smooth floors. It provides convenient access, good retention of restorations, and bulk.

A cavity shape that makes the restorative process easier for the dentist.

Carefully removing any remaining decay in teeth after completing cavity preparation.

The depth of a cavity preparation relative to the pulp. It is usually 0.5 - 1 mm beyond the DEJ (dentino-enamel junction) or 1.5-2 mm in whole cavity.

Detection of caries spreading sideways at the junction of enamel and dentin.

Sufficient material for a restoration to fill the cavity.

Added features to keep the restoration in place.

Healthy, strong dentin, ideal for cavity preparation.

Strong dentin that's discolored, often due to bacteria.

Decayed dentin that must be removed to prevent pulp involvement.

Instruments with a spinning cutting head used for removing caries.

Instruments used for scraping and removing caries.

Points at the top of the pulp chamber, closest to the tooth's surface.

Using instruments to remove material in a curved scraping motion.

Prepared areas in dentin that serve as a seat for restoration.

Applying material directly over the pulp to protect it.

Preparing the area around pulp to support a protective layer.

Cavity surface area, the part where the restoration meets the tooth.

Enamel that is damaged or loose at the cavity's edges.

Tools used to refine margins of cavity for restoration bonding and aesthetic.

Adding a sloping angle on the enamel wall.

A filling material commonly used in dentistry.

Strong filling material, durable for tooth restoration.