The purpose of this study was to compare microtensile bond strengths (µTBS) of silorane-based composite [Filtek P90, 3M ESPE (SBC)] repaired with two different materials and two different surface treatments. The two materials used to repair SBC were methacrylate-based composite [Filtek Z250, 3M ESPE (MBC)] and SBC. The two different procedures used different polishing abrasives. Circular discs of SBC were fabricated and aged by thermocycling for 5,000 cycles. Groups 1 and 2 used MBC with polishing procedures by 80-grit and 600-grit silicon carbide papers, respectively. Groups 3 and 4 used SBC with polishing procedures by 80-grit and 600-grit silicon carbide papers, respectively. Adhesives were used according to the repaired materials and following manufacturer's instruction. Unrepaired samples of SBC were used as a control group. Resin blocks were stored in 37°C water for 24 hours or aged by thermocycling for 5,000 cycles before the test. Test specimens were sectioned and trimmed to obtain slabs of 1 mm² bonded area for each group (n=20). µTBS was measured with universal testing machine using a crosshead speed of 1.0mm/min. Data were analyzed by two-way ANOVA and Tamhane post-hoc tests (alpha = 0.05). All repaired groups showed significantly lower µTBS than the control group and showed no significant difference in µTBS between each repaired group. Significant influence of the aging time was observed only in repaired group.