Antibacterial activity of a triclosan-containing resin composite matrix against three common oral bacteria

This study investigated the antibacterial effect of a resin composite matrix with or without incorporated triclosan (0.3 wt%) on Streptococcus mutans, Actinomyces viscosus and Lactobacillus casei. In the quantitative assay, bacterial suspensions were filled into 20-μl cavities within temporary restorative resins. After 0, 4, 8, 12, 24 and 48 h of incubation, the suspensions were removed from the restoratives and the numbers of viable bacteria were determined. Bacterial suspensions incubated without restoratives served as the controls. Ten replicates were carried out for each experiment. The resin composite containing triclosan demonstrated variable degrees of antibacterial activity against the microorganisms, revealing a significant inhibitory effect on S. mutans within 12 h compared to the control. The viable counts of A. viscosus significantly decreased after 24 h. A significant reduction of L. casei was observed after 48 h. The unloaded resin composite did not reveal a marked antibacterial effect. The resin composite loaded with triclosan might be beneficial in preventing cavity contamination and minimizing the risk of pulpal irritation in the short-term.