Chipping Resistance of Nanosilica Treated Zirconia Cores Veneerd with Porcelain after Thermocycling and Cycling Loading

Abstract

Aim: This study was conducted to evaluate the effect of nanosilia surface coating of pre-sintered zirconia on chipping of veneered zirconia crowns after thermocycling and cyclic loading. Method: Twenty zirconia cores were subjected to nanosilica slurry treatment before sintering then veneered and fired to produce crowns. The crowns ere cemented by resin cement on their epoxy dies and 10 crowns were subjected to 10000 thermocycles and 10000 cyclic loading. All crowns were loaded till chipping of veneer layer then the chipped surfaces were examined by SEM/EDX. Results: Crowns which were subjected to thermocycling and cyclic loading gave lower chipping resistance than the non-aged crowns. Conclusions: Treatment of zirconia cores with nanosilica before sintering and after thermal and mechanical aging didn’t increase the chipping resistance of the veneer layer.