Acción antibacteriana in vitro de dentífricos sin flúor frente a cepas de Streptococcus mutans

Introduction: Toothpastes with active ingredients prevent dental caries in children. Objective: Determine the in vitro antibacterial activity of three fluoride-free toothpastes and two control solutions against standard Streptococccus mutans strains. Methods: A prospective cross-sectional experimental double-blind study was conducted. Trypticase soy agar was used applying the diffusion method at 37 °C for 24 h. The size of the growth inhibition haloes of each group was examined. Data analysis was based on SPSS15 software, using Shapiro-Wilk Gaussian distribution corroboration statistical tests, and the Kruskal-Wallis and Mann-Whitney tests. Results: Inhibition diameter was 26.69 mm (± 1.85) for 0.12 % chlorhexidine gluconate, 6 mm (± 0) for distilled water, and 6 mm (± 0) and 22.93 mm (± 3.39) for the toothpastes. Comparison of the diameters obtained by the action of 0.12 % chlorhexidine gluconate and distilled water with the fluoride-free toothpastes revealed statistically significant differences in only one of the cases ( p < 0.05). Conclusions: Not all the baby toothpastes studied display antibacterial activity against the Streptococcus mutans strain ATCC 25175.