The aim of this study was to compare the microleakage of class V cavities restored by silorane resin with those restored by the methacrylate resin system. Sixty standardized class V cavities were prepared on premolars. The teeth were restored with Filtek(TM) Silorane and Silorane(TM) System Adhesive, Filtek(TM) Silorane and Adper(TM) Easy One and Filtek(TM) Supreme XT and Adper(TM) Easy One. The area and the depth of dye leakage were measured. Considering dye leakage area, the best results were achieved in group I (mean-M=0.114±0.083 mm(2)), then in group III (M=0.384±0.480 mm(2)) and finally in group II (M=5.389±6.587 mm(2)). Considering the depth of dye leakage, there was a significant difference between group I (mean rank-m.r.=1.23±0.44 mm) and II (1.98±0.83 mm), group II and III (1.23±0.40 mm). In this study silorane composite and its adhesive showed less microleakage than the methacrylate composite, and it showed compatibility only with its assigned adhesive.
Clinical significance: Less microleakage of silorane restorations could provide better and long lasting composite fillings.