Methodology for proximal wear evaluation in posterior resin composites.

The purpose of this study was to utilize a methodology to measure proximal wear of posterior resin composites with respect to time. A group of 10 teeth (5 premolars and 5 molars) were restored with P-30, a posterior resin composite restorative. At placement the proximal contacts were judged to be closed visually, and with unwaxed dental floss. The patients were then recalled at intervals of 6, 12, and 36 months for indirect wear evaluations. Resin composite transfer copings were made and indexed on baseline models. A zoom stereomicroscope, at 20 microns resolution, was used to determine proximal wear. For the posterior restorative material the premolar and molar teeth wore at the same rate. The amount of wear was statistically greater for premolar teeth at 6 and 12-month evaluation periods than molar teeth. At 36 months, there was no statistical difference in wear between premolar and molar teeth.