RESUMEN
OBJECTIVE: This study aimed to evaluate possible DNA damages to oral epithelial cells exposed to whitening kinds of toothpaste considering the effect of conventional non-whitening toothpaste. MATERIALS AND METHODS: Sixty volunteers were assigned into three experimental groups, each of them using a different regular toothpaste for the initial 2 months, followed by the use of whitening kind of toothpaste of the same brand for next 2 months. The oral epithelial cells were sampled prior and 30, 60, 90 and 120 days after the beginning of the use of tested kinds of toothpaste. Chromosomal damages were analyzed by micronucleus assay. RESULTS: For just one kind of tested whitening toothpaste was observed the significant increase in the number of micronucleated cells after 60 days of use compared values obtained 60 days of usage of conventional non-whitening toothpaste (6.35 ± 3.67 and 2.8 ± 1.91; p < .05). There was no statistically significant difference in other micronucleus assay endpoints between tested types of toothpaste at either of the sampling times during the period of toothpaste application. CONCLUSIONS: Based on the results, it can be concluded that the use of certain whitening kinds of toothpaste may cause a limited biologically insignificant genotoxic effect on buccal epithelial cells.