Bond to Zirconia Ceramic: Evaluation of Different Primers and a Universal Adhesive

Objective: The aim of the study was to evaluate the effect of a universal adhesive and different primers on the bond strength to zirconia ceramic. Materials and Methods: Seventy-five zirconia ceramic samples were obtained and divided into five groups (n=15): G1–Scothbond Universal (SBU); G2 – silane + SBU; G3 - Signum Zirconia Bond; G4 - Z-Prime Plus; G5 - MZ Primer. A cone of composite resin was built. The specimens were stored in 100% relative humidity with distilled water at 37°C for 48 h and then submitted to a tensile bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. The type of failure that occurred during the de-bonding procedure was analyzed. Results: The mean results of the bond strength test (MPa) followed by the same letter represent no statistical difference by ANOVA and Tukey’s post-hoc test ( p <0.05): G2=27.55 a (±6.99), G4=23.71 a (±5.65), G1=22.64 a (±5.67), G5=13.64 b (±5.49), G3=7.54 c (±4.75). G2 and G4 exhibited predominantly cohesive failure in the composite resin cone. G1 and G5 had predominantly mixed failures, and G3 exhibited only adhesive failures. Conclusion: The SBU and Z-Prime Plus provided higher bond strength to zirconia ceramic.