Natural Toothpaste Effects on Bacterial Coadhesion at Pellicle-Coated Surfaces

Natural based products including toothpastes grow in popularity with consumers. Ingredients used in natural dentifrice formulations may produce acute or subchronic effects including influences on bacteria, tooth surfaces or the interfaces between them. Objective: This study compared natural toothpastes containing propolis or essential oils to standard fluoridated dentifrices for effects on surface adhesion and coadhesion of Streptococcus oralis J22 and Actinomyces naeslundii T14V-J1 in vitro. Methods: Detachment of the co-adhering bacterial pair by the toothpaste supernates developed from 25% water slurries of formulations was studied in the parallel plate flow chamber on a 16h pellicle coated surface as described in detail (Busscher et al., J Dentistry 35: 294-301, 2007). Here paste treatments included: I: NaF dentifrice, II: SnF2 dentifrice, III: NaF dentifrice containing a mixture of fixed essential oils including thymol, eucalyptol, menthol; IV: a NaSMFP dentifrice containing propolis extract. After detachment by rinsing with a dentifrice supernates, re-deposition was initiated by flowing with a fresh streptococcal suspension. Results: Effects for initial bacterial detachment (% of non treated) followed II (54) = IV (54) > I (30) > III (10) p<0.05. Redeposition (% of post treated) followed: I (0) = III (10) < II (56) = IV (56) p<0.05. Large aggregation (% of aggregates) followed: I (25) = II (32) = III (25) < IV (45) p<0.05. Conclusion: So-called natural dentifrices containing essential oils or propolis exhibited significant effects on bacterial coadhesion to pellicle-coated surfaces different from standard fluoridated or dentifrices containing NaF or SnF2.