Evaluation of Zirconia/Resin Bond Strength and Interface Quality Using a New Technique

Purpose: Selective infiltration etching is a newly developed surface treatment used to modify the surface of zirconia-based materials, rendering it ready for bonding with resin cements. The aim of this study was to evaluate zirconia/resin bond strength and durability using the new technique. Materials and Methods: Zirconia disks received one of the following surface treatments: selective infiltration etching or airborne-particle abrasion with 50-mu m aluminum oxide particles, while as-sintered surfaces served as control. The zirconia disks were bonded to pre-aged composite resin disks using a light-polymerized adhesive resin (Panavia F 2.0). Zirconia resin bond strength was evaluated using the microtensile bond strength test (MTBS) and the test was repeated after each of the following intervals of accelerated artificial aging: thermocycling (10,000 cycles between 5 degrees C and 55 degrees C), 4 weeks, 26 weeks, 52 weeks, and 104 weeks of water storage (37 degrees C). A repeated measures ANOVA and Bonferroni post-hoc tests were used to analyze the data (n = 18, alpha = 0.05) Results: There were significant differences in the MTBS values between the three test groups at each of the test intervals (p < 0.001). After 2 years of artificial aging, all specimens of the control group demonstrated spontaneous failure, while significant reduction in the bond strength of the particle-abraded groups was observed (21.3 MPa). The bond strength of the selective infiltration etched group was relatively stable (44.1 MPa) after completion of artificial aging. Conclusion: Within the limitations of this study, micromechanical retention and adhesion promoters are prerequisites for establishing a strong and durable bond to zirconia-based materials.