Effect of Various Surface Conditioning Methods on the Adhesion of Dual-cure Resin Cement with MDP Functional Monomer to Zirconia after Thermal Aging

This study evaluated the effect of chairside and laboratory types of surface conditioning methods on the adhesion of dual-cure resin cement with MDP functional monomer to zirconia ceramic after thermocycling. Disk-shaped (diameter: 10 mm, thickness: 2 mm) Y-TZP ceramics (Lava™, 3M ESPE) were used (N=40) and finished with wet 1200-grit silicon carbide abrasive paper. Specimens were randomly divided into four experimental groups according to the following surface conditioning methods (n=10 per group): Group 1—Chairside airborne particle abrasion with 50-μm Al2O3 + Alloy Primer (Kuraray); Group 2—Airborne particle abrasion with 50-μm Al2O3 + Cesead II Opaque Primer (Kuraray); Group 3—Airborne particle abrasion with 50-μm Al2O3 + Silano-Pen + silane coupling agent (Bredent); Group 4—Laboratory tribochemical silica coating (110-μm Al2O3 + 110-μm SiOx) (Rocatec) + silane coupling agent (ESPE-Sil). Adhesive cement, Panavia F 2.0 (Kuraray), was bonded incrementally to the ceramic surfaces using polyethylene molds (diameter: 3.6 mm, height: 5 mm). All specimens were thermocycled (5 and 55°C, 6,000 cycles) and subjected to shear bond strength test (1 mm/min). Data were statistically analyzed (one-way ANOVA, α=0.05), whereby no significant differences were found among the four groups (8.43±1.3, 8.98±3.6, 12.02±6.7, and 8.23±3.8 MPa) (p=0.1357). Therefore, the performance of chairside conditioning methods used for zirconia was on par with the laboratory alternative tested.