Antibacterial activity of self-adhesive resin cements against Streptococcus mutans at different time intervals

Background and Objectives: Self-adhesive resin cements release fluoride and have cytotoxic and preventive monomers against the bacteria in their composition. They have acidic property before their complete setting too. The antibacterial ac- tivity of three different self-adhesive resin cements against Streptococcus mutans at different time intervals was investigated in this study. Materials and Methods: The modified direct contact test was used to evaluate the antibacterial effect of Max-Cem, G-Cem and Bis-Cem on S. mutans after aging the samples in phosphate-buffered saline solution for one hour, 24 hours and 1 week. Data were analyzed using one-way ANOVA, repeated measurement ANOVA and Tukey HSD tests (P<0.05). Results: The differences in the mean bacterial counts between all the study groups and between the study groups and the corresponding control groups were significant at 1-hour and 24-hour intervals (P<0.001). At 1-week, only the differenc- es between Bis-Cem and G-Cem, between Max-Cem and Bis-Cem, and between Bis-Cem and the corresponding control group were significant (P<0.001). There were significant differences between G-Cem and Max-Cem at all the time intervals (P<0.001). In addition, with the use of Bis-Cem there were significant differences between 1-hour and 1-week (P=0.01) and 24-hour and 1-week (P<0.001). Conclusion: All the cements exhibited antibacterial activity after 1 hour and 24 hours. However, after 1 week, only Bis-Cem retained its antibacterial activity.