Aim: to evaluate the wear of human enamel and different types of composite resin restorative materials when they oppose each other
Materials and methods: six different types of restorative resin composites (Grandioso, Activa, Z250, Brilliant everglow, CAPO, Herculite XRV) were opposed by human enamel in a chewing simulator (Robota, Germany) the chewing simulator was adjusted to perform a sliding distance of 1mm under a constant force of 50N while composite is in contact with enamel. the loss of weight of enamel and opposing composite was considered as a value for the wear.
Results: The highest wear was that of Grandioso heavy flow(5.8mg) followed by brilliant everglow (4mg) and Herculite ultra enamel(2.5mg) respectively and there was statistically significant differences among them as well as other materials. and the least values were recorded for CAPO (1.22mg), Z250 (1.24) and Activa (1.27) that were not statistically significantly different. Regarding opposing enamel wear the highest wear value was that of enamel opposing Brilliant everglow(7mg) and Z250 (6.4mg) both values were not statistically different. The values of Heculite ultra enamel (4.6) and Grandioso heavy flow (4mg) had no significant differences between them but showed significant difference with the above groups. The enamel wear opposing Activa (1mg) and CAPO (1.8mg) showed no statistically significant differences between them while they were significantly less than other groups.
Conclusions: Different composite formulations recommended for use in stress bearing areas have different wear rates, opposing enamel wear is important to study as it is independent of composite wear.