Bond of a New Self-etch Adhesive to Alumina and Zirconia

Objectives:  This study measured and compared the shear bond strength of resin composite to the high-strength ceramics alumina and zirconia after different surface treatment methods and application of either a new self-etch adhesive or a prominent zirconia primer. Methods : A total of 72 specimens were fabricated from a commercially available zirconium-oxide ceramic (Lava, 3M ESPE, n=36, group ZIR) and an aluminum-oxide ceramic (Vita, n=36, group ALU). Surface treatment protocols consisted of air-particle abrasion (aluminum oxide) followed by application of a new self-etch adhesive (3M ESPE, subgroup SEA) or Z-Prime (Bisco, subgroup ZPR). As a control, a combination of CoJet tribochemical surface treatment, ceramic primer (RelyX Ceramic Primer, 3M ESPE), and an adhesive (Adper Single Bond Plus, 3M ESPE) was applied (subgroup COJ). Bond strength was tested after 10,000 thermal cycles (5 to 60⁰C, dwell time 15 second). Data was analyzed with one-way ANOVA (p<0.001), and paired comparisons between groups were done with Tukey test (p<0.05). Results:  For group ZIR, mean bond strength values [MPa] and SD were: SEA 23.19 ± 4.49 (a), ZPR 10.97 ± 2.53 (b), COJ 0.82 ± 0.49 (c). For group ALU, they were: SAE 17.49 ± 3.67 (a), ZPR 7.05 ± 1.64 (b), COJ 1.09 ± 0.81 (c). Same letters in parentheses indicate no statistically significant difference. Conclusions:  Type of adhesive and surface treatment significantly influence composite-resin bond strengths to zirconia and alumina. Performance of the different bonding protocols was not influenced by the ceramic substrate. The new self-etch adhesive (SEA) provides superior bond strength to zirconia as well as alumina ceramics.