[Influence of tribochemical silica coating on shear bond strength of a dental zirconia ceramic to resin cements].

PURPOSE: To evaluate the effect of tribochemical silica coating for zirconia bonding.

METHODS: Sixty cut and fully sintered Lava frame zirconia blocks were randomly divided into 6 groups and subjected to 3 different surface treatments and 2 kinds of resin cement.The surface treatments were airborne-particle abrasion/silane, airborne-particle abrasion/CoJet Sand (tribochemical silica coating) /silane and no treatment(control), resin cements were RelyX Unicem and Panavia F2.0. Half of the specimens in each group were randomly chosen and stored in 37℃ distilled water for 24h, the others were thermocycled (5℃ and 55℃) for 5000 cycles. All specimens were subjected to shear bond strength(SBS) testing. SBS values were analyzed by two-way ANOVA and t test, and multiple pairwise comparisons were then completed with post hoc Tukey test. Statistical analysis was performed using SPSS23.0 software package for Windows.

RESULTS: Airborne-particle abrasion/CoJet sand/silane group resulted in a significantly higher SBS than those in other groups (P<0.001). After thermocycling, the bond strengths in the airborne-particle abrasion/CoJet Sand/silane groups bonded with RelyX Unicem showed no significantly decrease while marked drop appeared in all other groups.

CONCLUSIONS: Combination of tribochemical silica coating with silane coupling can effectively enforce the bond strengths of zirconia (Y-TZP). Attention should be paid to the interaction between surface treatments and resin cements.