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 zirconiabased 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-μm 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°C and 55°C), 4 weeks, 26 weeks, 52 weeks, and 104 weeks of water storage (37°C ). A repeated measures ANOVA and Bonferroni post-hoc tests were used to analyze the data (n = 18, α = 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.