Microtensile bond strength of a resin cement to silica-coated and silanized in-ceram zirconia before and after aging

Purpose: This study compared the microtensile bond strength of resin-based cement (Panavia F) to silica-coated, silanized, glass-infiltrated high-alumina zirconia (In-Ceram Zirconia) ceramic in dry conditions and after various aging regimens. Materials and Methods: The specimens were placed in 1 of 4 groups: group 1: dry conditions (immediate testing without aging); group 2: water storage at 37 degrees C for 150 days; group 3: 150 days of water storage followed by thermocycling (X 12,000, 5 degrees C to 55 degrees C); group 4: water storage for 300 days; group 5: water storage for 300 days followed by thermocycling. Results: Group 1 showed a significantly higher microtensile bond strength value (26.2 +/- 1 MPa) than the other aging regimens (6.5 +/- 1, 6.2 +/- 2, 4.5 +/- 1, 4.3 +/- 1 Wa for groups 2, 3, 4, and 5, respectively) (P <.01). Conclusion: Satisfactory results were seen in dry conditions, but water storage and thermocycling resulted in significantly weaker bonds between the resin cement and the zirconia.