ABSTRACT
Objective:To evaluate the wear resistance of four types of composite resin when they were opposed by human enamel antagonist. The relationship between pH value and wear resistance was also evaluated. Methods:Mutual wear between four types of composite resins(3 mm?20 mm?1 mm),Beautifit(B),SureFilTM(S),TE-Econom(T),Charisma (C),with same rough surface and opposing enamel was evaluated using a wear simulator of UMT-2 (n=10).Wear resistance was assessed as weight loss(g).The worn surfaces were observed with scanning electron microscope(SEM).All data were statistically analyzed with SPSS14.0.Results:SEM observation showed that the fillers particles of resin B,S were bigger than that of the others. Fillers of resin C was the smallest and the most well-distributed. Many filler particles were lost. In the acid environment,the enamel surface had the special appearance. The S,C,T composite resins were less worn. The weight loss of the T,B,S composite resins increased when pH value fell down to 4.0 (P0.05).Conclusion:The wear resistance among the different brands of composite resins are discrepant. The weight loss might be accelerated with the decreased pH value.