Micro-Tensile Bond Strength Between a Resin Cement and an Aluminous Ceramic Treated with Nd:YAG Laser,Rocatec System,or Aluminum Oxide Sandblasting

Objective: The aim of this study was to evaluate the effect of different surface treatments on bond strength between In-Ceram Alumina (VITA) and Panavia Fluoro Cement (Kuraray), and to verify the association between bond strength values and the percentage of remaining cement on the ceramic surface. Background Data: Although several conventional surface treatments have been used on aluminous ceramic, no study investigated the effect of the Nd:YAG laser. Methods: Nine In-Ceram Alumina blocks (10 × 10 × 6 mm) received three surface treatments: group 1, Al₂O₃ sandblasting + silane; group 2, Al₂O₃ sandblasting + Rocatec Plus + silane; and group 3, Al₂O₃ sandblasting + Nd:YAG Laser + silane. Resin cement was applied and light cured, followed by the application of composite. Blocks were sectioned to obtain sticks with a cross-sectional area of 1.0 mm². Microtensile bond strength (µTBS) was recorded in a universal testing machine at a crosshead speed of 0.5 mm/min. Scanning electron microscopy images of the fractured areas were used to calculate the amount of remaining cement on the ceramic substrate. Results: All treatments yielded statistically different µTBS values (MPa): group 1, 14.38^A; group 2, 20.09^B; and group 3, 23.21^C (ANOVAand Tukey's test,α = 0.05). Pearson's correlation coefficient for µTBS × percentage of remaining cement was r = 0.92 (p < 0.05).Conclusions: The Nd:YAG laser was the most effective surface treatment, followed by Rocatec and Al₂O₃ sandblasting. A strong positive association was found between bond strength values and percentage of remaining cement.