Antimicrobial efficacy of antiplaque agents of common toothpastes against Porphyromonas gingivalis and Streptococcus oralis: An in vitro study

This study was designed to evaluate the antimicrobial activity of common gum protection and antiplaque toothpastes against Porphyromonas gingivalis ( P. gingivalis ) and Streptococcus oralis ( S. oralis ) as important periodontal pathogens. This experimental study investigated the antimicrobial activity of 15 commonly used toothpastes from different companies on the two common types of periopathogens, S. oralis and P. gingivalis . The antimicrobial activity of toothpaste was evaluated at three concentrations of 100%, 50%, and 25% and analyzed by agar well diffusion plate method and zone of inhibition. The obtained data were compared and statistically analyzed by SPSS software using one-way ANOVA and the least significant difference post hoc tests (α = 0.05). One-way ANOVA showed that the mean diameter of the two-bacterial zone of inhibition was significantly different at 100%, 50%, and 25% concentrations of toothpastes ( P < 0.001). In general, the mean diameter of the zone of inhibition was greater at 100% concentration than the other two concentrations in all toothpastes. The highest zone of inhibition of the S. oralis was in the toothpastes containing tin. Further, the highest zone of inhibition of P. gingivalis was found in the triclosan-containing toothpastes. Toothpastes containing triclosan had the most antimicrobial activity against P. gingivalis . Moreover, toothpastes containing tin compounds had the most antimicrobial effect against S. oralis .