Cytotoxicity and Genotoxicity of Fluoride Toothpastes in Buccal Cells

This study investigated whether toothpastes containing different fluoride compounds influence cytotoxic and genotoxic alterations in buccal mucosal cells, with particular attention to the type of fluoride, the presence of fluoride itself, and the duration of exposure.

Eighty-eight participants were randomly assigned to four parallel groups: a control group using fluoride-free toothpaste and three intervention groups using formulations containing sodium fluoride, sodium monofluorophosphate, or amine fluoride. Buccal cell samples were obtained at baseline (T0), after 30 days (T1), and after 45 days (T2), and evaluated using the buccal micronucleus cytome assay to quantify nuclear abnormalities and cytotoxic markers.

All fluoride-containing toothpastes led to higher frequencies of micronuclei, nuclear buds, and "broken egg" cells at T1 and T2 compared with the control group (P ≤ 0.001). Amine fluoride and sodium monofluorophosphate produced sustained increases in cytogenetic markers, including nuclear buds (AmF: P = 0.013; NaMFP: P ≤ 0.001) and "broken egg" cells (AmF: P ≤ 0.001; NaMFP: P = 0.004), while sodium fluoride demonstrated a slower, progressive increase in "broken egg" cells (P = 0.036).

The findings suggest that fluoride-based toothpastes may modulate cytogenetic responses in buccal epithelial cells, and that these effects differ according to the fluoride compound and exposure duration. The findings should be interpreted with caution due to study limitations, and further research is needed to clarify the long-term biological consequences of repeated fluoride exposure in oral hygiene.