Comparative in Vitro Study of Antimicrobials against Oral Biofilms of Streptococcus Mutans

In the study four types of antibacterial agents were used: Chlorhexidine, Sodium benzoate, Cinnamon oil and Xylitol. These categories of antibacterial agents were selected to represent antibacterial agents of diverse origin and widely differing modes of action. The aim of this study was to compare the four mentioned antibacterials, which are commonly used in toothpastes, mouth rinses and even chewing gum, against biofilms of Streptococcus mutans formed in vitro which is a cariogenic organism. The effect of individual antibacterial was studied by growing the biofilms on conventional microscopic slides. The biofilms were allowed to grow in the culture medium for a period of 54 hours, after which the earlyformed biofilms were exposed daily for a period of 1 minute over a period of 3 days to various concentrations of the antimicrobials individually. Simultaneously early-formed biofilms were treated with saline as a control. The final treated biofilms (126 hour old) were harvested and the cell viability and glucan accumulations of the biofilms were determined. The number of viable organisms, for all the antimicrobials tested, i.e. the count of viable organisms was seen to decrease at least by 1 log10 fold, indicating their effectiveness in detachment of preformed S. mutans biofilms. However on checking the amount of soluble glucans produced by the biofilms the range of values obtained were falling outside the standard range. Hence indicating that the amount of soluble glucans was negligible and the reason for formation of biofilms in this study was not due to soluble glucans, hence in the light of the experiments performed it can be concluded that out of all the four antimicrobials used Xylitol was the most effective against the viability of S. mutans and in reducing the formed biofilms, followed by Chlorhexidine, Cinnamon oil and Sodium benzoate.