To evaluate the effect of various surface treatments of natural tooth on the bond strength of nickel-chromium alloy when cemented with self-adhesive resin cement.
Materials and Methods: This in vitro study was conducted on 48 freshly extracted non-carious human premolars and class 1 inlay cavity was prepared on the occlusal surface. Wax pattern with a loop on the occlusal surface was prepared on each specimen using standard procedures and then inlays were casted with Ni-Cr alloy. Specimens were then divided into 4 groups of 12 each. Group 1: Control, Group 2: Grit blasting with 110µm Al2O3, Group3: Ultrasonic instrumentation and Group 4: Grit blasting followed by ultrasonic instrumentation. The specimens were then cleaned, cemented with self-adhesive resin cement and were loaded on universal testing machine, at a cross head speed of 1 mm/min. The loads at debonding were noted and tensile bond strength was calculated in MPa.
Statistical Analysis Used: One-way ANOVA and Post Hoc Test.
Results: The means for tensile bond strength for Group 1, 2, 3 and 4 were found to be (37.20±10.97), (43.09±13.47), (47.61±12.41) and (70.67±17.58) MPa respectively. Means of tensile bond strength among the groups were compared using one-way ANOVA and comparison between individual groups were made with Post Hoc Bonferroni test. Among all the groups, Group 4 (70.67±17.58 MPa) showed the highest bond strength values and p value is <0.001 which denotes that the difference in tensile bond strength between the resin cement bonded with base metal alloy in this study was statistically significant.
Conclusion: Among all types of surface treatments used in this study, sandblasting improves the bond strength and the best results can be achieved with a combination of gritblasting and ultrasonic instrumentation. Therefore surface treatment have an important role on the bond strength of ceramic-metal interface.