Method: Forty plates of zirconium (Y-TZP) ceramics were randomly assigned to four groups (n=10). A femtosecond amplifier laser pulse (Quantronix Integra -C-3.5) was applied on zirconia (Y-TZP) surface with different incidence angles (90°, 75°, 60°, 45°). The resin cement (RelyXTM U100 Self-Adhesive Resin Cement, 3MTM ESPETM) was adhered onto the zirconia surfaces. Shear bond strength of each sample was measured using universal testing machine at crosshead speed of 1 mm/min. Shear bond strengths were analyzed through one-way ANOVA/Tukey tests.
Result: The results showed that the degree of laser angle beam affects the shear bond strength of resin cement to zirconium ceramic. The laser beam was applied to surface with a 45 ̊ degree angle resulted in significantly higher shear bond strength (18.2 ± 1.43) than other groups. (degree of 90°, 10.79 ± 1.8 MPa ; degree of 75°, 13.48 ± 1.2 MPa; degree of 60°, 15.85 ± 0.81 MPa ; P < .001)
Conclusion: This study shows that decreasing of the angle between the ceramic surface and the laser beam increased the SBS between the resin cement and the ceramic material, as well as the orifice.