Comparison of three standards for quantifying occlusal loss of composite restorations.

Occlusal loss of resin composite in posterior restorations may be measured by assessing the exposure of cavity walls. The purpose of this study was to compare three standard scales used to quantify occlusal loss on stone replicas of posterior composites. Measurements of occlusal loss, on 60 stone replicas selected from two clinical studies, were obtained by comparison with three standard scales: L-calibrated die stone standards derived from clinical restorations (Leinfelder), M-dies with cylindrical incremental defects (M-L scale), and V-tooth-sized dies with restoration-like incremental defects (Vivadent). Evaluators with different dental and evaluating experience carried out the assessment using each standard on two different occasions. Differences among results obtained using the three standard scales were comparatively small when assessments were carried out by experienced evaluators. Use of the V standard consistently achieved a higher level of agreement by pairs of evaluators.