The objectives of this study were to determine the wear resistance of dental resin composites, and to evaluate the influence of wear-simulating apparatus on wear. Nine commercial resin composites were studied. Wear was simulated with an oral wear simulator (Proto-Tech), which simultaneously incorporates the wear mechanism of attrition and abrasion in three-body wear mode, and with a pin-on-disk type friction tester (Rhesca, Japan). Composite specimens were subjected to 50,000 cycles of wear against a dental porcelain antagonist. After wear simulation, parameters for the determination of wear amount, such as wear volume, maximum wear depth, mean of maximum wear depth, and average wear depth were measured with the use of a 3D profilometer. For the oral wear simulator, the range of wear volume was 4.3-9.2 x 10(-2) mm3, and there were significant differences among the composites (p < 0.05). In other parameters, there were no significant differences among the composites. For the pin-on-disk tester, the range of mean of maximum wear depth was 7.5-26.3 microm, which was significantly different among the composites (p < 0.05). Correlation coefficient (r) between the wear volume from the oral wear simulator and the mean of maximum wear depth from the pin-on-disk tester was 0.52. Conclusively, dental resin composites showed significantly different wear resistance. Wear simulating apparatus influenced the amount of wear, and suitable parameters for the determination of wear amounts should be selected in each apparatus.
(c) 2004 Wiley Periodicals, Inc.