Abstract: Objective: To explore the differences of wear resistance of three kinds of glass ceramics and Wieland Zenostarzircona (Zenostar),and to clarify their influencing factors.Methods: Zenostar were made into flat-shaped specimens(zirconia base sample group) and hemisphere-shaped specimens (zirconia pair grinding group).There kinds of glass ceramics IPS Empress(Empress),IPS e.max CAD(e.max),VITA Suprinity (Suprinty) were used as base specimens.Each group was exposed to UMT-2 testing machine to simulate the clinical service.The wear depthes of base specimens were detected by laser confocal scanning.Scanning electron microscope(SEM) was used to evaluate the wear surfaces.Results: In zirconia base sample group,there were no significant differences in the maximum wear depthes to Zenostar between the three kinds of glass ceramics(P>0.05).In zirconia pair grinding group, the maximum wear depthes ranked as follows:Zenostar groupP>0.05),but there were significant differences between other groups (P<0.01).The SEM results showed that the wearing surface of the Zenostar in zirconia base sample group was relatively smooth;whereas the wearing surface of Empress in zirconia pair grinding group was rougher with alarge area of clebris desquamation surface.Conclusion: The wear resistance of the three kinds of glass ceramics to Zenostar is related to the compositions and the chemical structures of materials.

Key words: glass ceramic, zirconia, friction and wear, wear depth