Mechanical properties,phase stability and biocompatibility of (Y,Nb)-TZP/Al2O3 composite abutments for dental implant.

Abstract

ZrO2/Al2O3 composites were prepared by mixing a tetragonal ZrO2, stabilized by 5.31 mol% Y2O3 and 4.45 mol% Nb2O5, and various amounts of Al2O3. Influence of the amount of Al2O3 on strength and toughness and tetragonal phase stability in the composites under autoclave conditions was investigated. In addition, in vitro and in vivo biocompatibility of the composites was examined. The composite, prepared with addition of 20 vol% Al2O3, exhibited the highest strength of 700 MPa and toughness of 8.1 MPa · m1/2 and showed no hydrothermal degradation while aging in an autoclave. The biocompatibility of the composite exhibited no cytotoxicity and no significant adverse soft-tissue response for up to 3 months implant period in guinea pigs. © 2000 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 53: 438-443, 2000