Cavity wall Internal surface of a cavity preparation.
Diastema (dye-uh-STEE-muh) A space between two teeth.
Esthetic (es-THET-ik) dentistry Type of dentistry that improves the appearance of teeth by camouflaging defects and whitening teeth.
Operative dentistry Term commonly used to describe restorative and esthetic dentistry.
Pulpal (PUL-pul) wall Surface of the cavity preparation perpendicular to the pulp of a tooth.
Resistance (ree-ZIS-tuns) form Shape and placement of cavity walls in preparation for tooth restoration.
Restoration (res-tuh-RAY-shun) Use of a dental material to restore a tooth or teeth to a functional permanent unit.
Restorative (re-STOR-uh-tiv) dentistry Type of dentistry that restores teeth by removing decay and restoring defects.
Retention (ree-TEN-shun) form Shaping of the cavity walls to aid in retaining the restoration.
Retention (retentive) pin Basis of a stronger system used to retain and support a tooth restoration.
General dentistry, also referred to as operative dentistry, remains the primary responsibility of the general dentist. This chapter presents background knowledge and describes the skills needed for the clinical dental assistant to gain knowledge of restorative and esthetic procedures such as amalgam restorations, composite resin restorations, intermediate restorations, resin veneers, and tooth-whitening procedures.
Restorative dentistry is indicated when teeth are to be restored to their original form and shape through the use of direct and indirect restorative materials. Specific conditions that determine the need for restorative dentistry include the following:
Esthetic dentistry is devoted primarily to improving the appearance of teeth by repairing imperfections with direct and indirect restorative materials, or by using whitening techniques. Specific conditions that result in the need for esthetic treatment include the following:
To restore a tooth to its normal function while still maintaining its esthetic appearance, the dentist must master a technique that involves following specific steps to complete the process of restorative dentistry. When preparing a tooth for a permanent restoration, the dentist has acquired knowledge about the direction of the enamel rods, the thickness of the enamel, the body of the dentin, the size and position of the pulp, and the crown of the tooth as it relates to the gingival tissues.
An understanding of the terminology of a cavity preparation will help you to know which dental instruments, dental accessories, and dental materials to have ready at the appropriate times throughout a procedure. The specific terminology refers to the anatomical structures as they relate to the cavity preparation, which is especially helpful for the expanded-function dental assistant (EFDA) in the application of dental materials and intermediate restorations. See Box 48-1 for tooth preparation terms.
Cavity preparation is the process of removing diseased tooth structure while leaving a limited amount of healthy tooth structure for the tooth to maintain a restoration. The principles of cavity preparation are divided into two stages, each with several steps. The dentist follows these steps in an exact order so that ideal results are achieved.
Cavity preparation involves the initial design and extension of the preparation’s external walls to a limited depth. The factors listed below are intended to help the dentist gain access to the decay or defect and reach sound tooth structure. The objectives for initial cavity preparation are as follows:
Standardized Plan for a Restorative Procedure
Dental Assistant’s Role in a Restorative Procedure
A permanent restoration can be anything from a small class I restoration to an extensive class II multisurface foundation. With the exception of steps added to the process by using supplementary accessories and dental materials, a restorative procedure will follow a standardized format.
Class I Restorations
The class I cavity, or lesion, is a one-surface lesion involving the pits and fissures of a tooth. Because of this anatomical feature, plaque and debris will accumulate within these areas, making it difficult for a patient to keep the areas clean. Therefore, the pits and fissures are highly susceptible to decay. Class I decay involves the following areas of concern:
The occlusal or lingual class I cavity preparation is a simple preparation for the dentist. The outline of the cavity preparation involves the pit, the groove, or a fissure that is decayed. The dentist will use a bur to open the enamel, taking care not to create any sharp angles or corners within the preparation. This preparation should be smooth throughout the internal structure (Fig. 48-6).
The location of the restoration in the mouth will determine the type of permanent restorative material to be used. Because class I lesions are small restorations and most likely do not interfere with occlusal forces, the dentist will commonly select a composite resin material for the permanent restoration.
Because class I restorations can occur on the occlusal surface, the dentist must evaluate the patient’s occlusion after replacing tooth structure. An easy way for the dentist to review how the tooth occludes with an opposing tooth is to mark the occlusion with articulating paper after the restorative process. See Procedure 48-1.