Wear test of composite restorative materials by a polishing machine.

The wear resistance of microfilled and conventional composite resins, was examined, using two sizes of abrasive particles for polishing. The mechanical properties of the composite resins were also studied and evaluated in relation to wear. Conventional composites showed much lower wear resistance than the microfilled resins. The amalgam and human enamel abraded with 10ƒÊm SiC particles, had strongest wear resistance, and those abraded with 20ƒÊm SiC particles had resistance similar to that of the microfilled resins in wear. The effect of the size of the abrasive particles on wear differed with the material tested. Filler content, the mechanical properties of knoop hardness, elastic modulus and destructive energy correlated well with wear rate.