Effect of autoclave treatment on bonding strength of dental zirconia ceramics to resin cements

Abstract

The purpose of this study is to evaluate the bonding strengths between dental zirconia ceramics with surface treatments and resin cements. Two types of zirconia (NANOZR and Y-TZP) and six types of dental resin cements were used in this study. All zirconia specimens were treated as follows; sandblasted with alumina, annealed at 1100°C and stored in an autoclave at 134°C for 5 hours. Half of specimens after stored in the autoclave were dried in an oven at 150°C for 3 hours. Adhesive procedure of the zirconia and resin cements was undertaken according to each manufacturer's direction. Shear bonding strengths between zirconia and resin cements were measured. The bonding strengths stored in the autoclave were higher compared with dried after autoclave treatment. XPS revealed that hydroxide or H2O adsorbed on the outermost layer of the zirconia after autoclave treatment. It is extrapolated that adsorbed hydroxide enhanced the bonding reaction between zirconia and resin cement. © 2010 The Ceramic Society of Japan.