Shear Bond Strength of Chemical and Light Cured Glass Ionomer Cements Bonded to Resin Composite

The purpose of this study was to compare the shear bond strength of chemically cured (Conventional) glass ionomer cement and light cured (Resin modified) glass ionomer cement to resin composite and to evaluate the effect of acid etching of the glass ionomer cements on the shear bond strength.Forty acrylic molds were prepared, a hole (6×2) mm was prepared in each mold to retain the glass ionomer cements (GICs). The samples were divided into two main groups. The first group were filled with Conventional GIC and the second group were filled with Resin modified glass ionomer cement (RMGIC), then each group were subdivided into two subgroups, the first subgroup were acid etched and the second subgroup were left without etching. The bonding agent applied to the demarcated bond area on the GIC surface, the composite resin cylinders were built up over the GIC base. The samples were stored for one week in deionized water then thermocycled. The samples then tested for shear bond strength (SBS) using universal testing machine.The result shows that Independent samples T-test used for statistical analysis. The result showed that RMGIC significantly had higher SBS than conventional GIC. No statistical difference was shown in SBS between subgroup etched and without etching for RMGIC, but the conventional GIC showed significantly higher SBS in subgroup without etching than with etching.This study Conclude that the SBS of RMGIC to resin composite was significantly higher than that of conventional GIC. Acid etching the GIC surface did not improve the SBS of GICs to resin composite.