Cuspal flexure of teeth with composite restorations subjected to occlusal loading.

Purpose: To measure in vitro the cuspal deflection produced by polymerization shrinkage and occlusal loading in mesio-occlusal (MO) and mesio-occlusal-distal (MOD) bonded composite restorations.

Materials And Methods: Twenty first premolars were studied, attaching a small crystal ball to each cusp vertex as a reference point for intercuspal distance measurements. MO cavities were made in ten premolars and MOD cavities in the other ten.

Influence of cavity type and size of composite restorations on cuspal flexure.

Objectives: The present study examines the influence of cavity type, and size of composite restorations on cuspal flexure due to polymerization shrinkage.

Methods: Thirty healthy premolars were selected and divided into two experimental groups. Group 1: Mesial, mesio-distal, and MOD cavities were successively prepared in each tooth by means of the SONICSYS approx system (KaVo) using a n 2 (small) diamond tip.

Effect of restorative procedures and occlusal loading on cuspal deflection.

This study examined the extent of cuspal flexure caused by progressively larger cavity preparations, including endodontic access, and progressive simulated occlusal loading with 50N, 100N and 150N. Ten intact extracted maxillary premolars were embedded in acrylic resin, and a small ball was attached to each cuspal tip as a reference point for intercuspal distance measurements. The teeth were subjected sequentially to the following procedures: conservative MO cavity preparation, extensive MO cavity preparation, endodontic access step and MOD cavity preparation.