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

ABSTRACT

OBJECTIVES: To investigate whether a stable bond could be obtained between resin-reinforced glass-ionomer 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 degrees 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 a = .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.