Bond durability of the resin-bonded and silane treated ceramic surface.

OBJECTIVES

The aim of this study was to explore methods for improving the ceramic-silane-resin bond strength of silica-based ceramics, such that it may be possible to eliminate the hazardous process of acid etching these dental ceramics with hydrofluoric acid (HF).

METHODS

Ni/Cr rods were prepared with ceramic facings, which were polished to a 1 microm finish. A silane coupling agent was applied to the ceramic surface using seven different procedures. Specimens were bonded using a luting resin and the tensile bond strength was measured at a crosshead speed of 1mm/min. One bonding procedure was selected and used for the comparison of four ceramic surface preparations consisting of; 1 microm polish, gritblasted (50 microm alumina), etched with 10% HF, and gritblasted and etched. The durability of the bond was assessed by (1) storing the specimens in water at 37 degrees C for different time periods up to 3 months, (2) thermal cycling, and (3) storing in water at 100 degrees C for 24h.

RESULTS

The results showed that one bonding procedure to a polished ceramic surface gave better results for the tensile bond strength of the resin to the smooth ceramic surface and that the tensile bond strength was not significantly different from the gritblasted, etched or gritblasted and etched groups (P>0.05). There was no deterioration in the tensile bond strength for any of the groups after water storage for up to 3 months or after thermal cycling (P>0.05). The silane bond was also capable of resisting hydrolytic attack in boiling water.

SIGNIFICANCE

The results indicate that a durable resin-ceramic tensile bond can be obtained by appropriate silane application without the need for HF acid etching the ceramic surface.