Effects of Curing Mode on the Bond Strength of Resin-Modified Glass Ionomer Cements

The purpose of this study was to evaluate the bond strength of resin-modified glass ionomer cements (RMGICs) with different curing mode. RelyX Luting 2(RL) and Nexus RMGI (NR) were bonded to enamel, dentin, cobalt-chromium alloy, and ceramic using light-curing and chemical-curing modes, separately. The bond strength of light curing was higher than that of chemical curing for all groups. The bond strength of RL and NR in the light-cured group was significantly higher than those in chemical curing for both enamel and cobalt-chromium alloy (P < 0.05). The most common mode of adhesive fracture was cohesive fracture. The difference of adhesive strength resulted from the difference of micromechanical interlocking of adhesive which came from the cohesive strength of RMGICs with light curing. FT-IR showed that light curing was followed by chemical curing, but the chemically cured samples could not be cured without an external light source. Thus, light curing is an essential procedure in improving bond strength when using dual-cured RMGICs in clinics.