Bonding property of two resin-reinforced glass-ionomer cements to zirconia ceramic

Objectives: To investigate whether a stable bond could be obtained between resin-reinforced glassionomer cement and zirconia ceramic. Method and Materials: Sixty disk specimens of a dental ceramic (Cercon zirconia ceramic, Dentsply) were made and treated by airborne-particle abrasion. They were divided into three groups and bonded to two resin-reinforced glass-ionomer cements (RelyX Luting [3M ESPE] and Fuji Plus [GC]) and one resin cement (Panavia F, Kuraray) as a control group. All bonded specimens of each group (n = 20) were stored in distilled water (37°C) for 24 hours, and half were additionally aged by thermocycling (20,000 times). Shear bond strength test was performed to measure the bond strength. Statistical analyses were performed using one-way ANOVA and paired t test with α = .05. The interfacial morphology of debonded specimens was observed by using a scanning electron microscope, and the mode of bonding fracture was evaluated. Results: The initial shear bond strength (in 24 hours) of the two resin-reinforced glass-ionomer cements to zirconia ceramic was 17.33 ± 3.53 MPa and 16.68 ± 2.76 MPa, and it dropped significantly to 7.62 ± 2.17 MPa and 4.65 ± 2.02 MPa after thermocycling. In the control group, the initial shear bond strength was 26.25 ± 5.61 MPa, and there was no obvious decrease after thermocycling. The bonding failure of resin-reinforced glass-ionomer cements was mostly adhesive failure between cement and ceramic. Conclusion: Resin-reinforced glass-ionomer cement could not offer a stable bond to abraded zirconia ceramic after thermocycling, and there was no durable chemical or mechanical bond between resin-reinforced glass-ionomer cement and zirconia ceramic. Palabras clave: bonding fractured mode, resin-reinforced glass-ionomer cement, scanning electron microscope, shear bond strength, zirconia ceramic