Objective:The purpose of this study was to investigate the effects of Class V cavities sealed with two dental materials, com- pomer and light-cured glass ionomer cement (LGIC), and how the design of cavities affects restoration effects.Methods:A total of 100 permanent posterior teeth were selected for this experiment, and five types of cavities were prepared buccally. The cavities were restored with the compomer Dyract and the LGIC Vitremer. After50 times of thermocycles, all the specimenswere immersed in 1% solution of methylene blue dye, and then sections of the restorations were evaluated under an Olympus stereomicroscope. Two of the specimens were observed under scanning electronic microscope (SEM).Results:Microleakage happened more fre- quently at the gingival site than at the occlusal site. At the enamel site, the cavity design had little influence on microleakage for these two materials; but at the gingival site, Type e leakage happened more frequently than Type a/b for the compomer, and the incidence of Type c/d leakage was less than Type a/b for the LGIC.Conclusion:The restoration effectof compomerDyractis bet- ter than that of LGIC.
