Thermocycling Effects on Resin Bond to Silicatized and Silanized Zirconia (original) (raw)

Various techniques have been introduced to create a durable resin-composite bond to sintered zirconia (Y-TZP). Shear bond strength values achieved through tribochemical treatment have been studied in numerous studies, but less is reported about long-term durability. The objective was to evaluate the effects of thermocycling and silane on shear bond strength of composite luting cement to silicatized Y-TZP. Two groups of Y-TZP (Procera Zirconia, Nobel Biocare), both consisting of 40 specimens were prepared. The specimen surfaces were air particle abraded by silica-coated aluminum trioxide particles (particle size 110 µm, duration 15 s, air pressure 300 kPa, nozzle-distance 10 mm). The silica-coated surfaces in group ZA were silanized with acrylate-functional silane (Experimental laboratory-made acrylate silane, Toray Dow Corning Silicone) and in the other group ZM with pre-activated methacrylate silane (ESPE Sil, 3M ESPE). The surfaces were coated with adhesive-system (Scotchbond 1, 3M ESPE) and photo-polymerized for 10 s. Resin-composite luting cement (RelyX ARC, 3M ESPE) stubs were added onto substrates and photo-polymerized for 40 s. The test specimens were thermocycled for 0, 1000, 3000, 8000 or 15000 times (temperature 5-55 °C, immersion time 20 s). The shear bond strengths of luting cement to ceramics were measured with a cross-head speed of 1.0 mm/min. ANOVA was used as statistical analysis. ANOVA revealed that both silane and thermocycling affected significantly (p < 0.001) on shear bond strength. Short term hydrolytic stability of acrylate silane was superior. The conclusion: estimation of bonding requires extended thermocycling.