In vitro effect of low-fluoride toothpastes containing sodium trimetaphosphate on enamel erosion

- Enamel treated with low-F toothpastes containing TMP is more resistant to erosive wear.
- Surface enamel is less softened when treated with TMP-containing toothpastes.
- Subsurface enamel is less softened when treated with TMP-containing toothpastes.

ObjectiveTo evaluate the effect of a low-fluoride dentifrice (LFD) containing sodium trimetaphosphate (TMP) on enamel erosion in vitro.DesignBovine enamel blocks (n = 144) were selected by surface hardness (SH) and subjected to erosive challenges, in two sets of experiments for 2 and 5 days. Blocks were randomly assigned to groups treated with slurries (5 mL/block, for 15 s) of following dentifrices: Placebo (no fluoride or TMP); LFD (250 ppm F); LFD plus 0.25, 0.5, or 1.0% TMP; and a commercial positive control (1,425 ppm F). The erosive challenge was produced by immersion in a soft drink (pH 2.8) for 5 min, four times/day, interspersed by immersion in artificial saliva for 1 h. SH and surface wear were analyzed as response variables. Data were submitted to 2-way ANOVA, followed by Student-Newman-Keuls test (p < 0.05).ResultsAll groups treated with LFDs containing TMP had significantly lower enamel wear when compared with the other groups tested (p < 0.001). Also, the LFDs containing TPM at lower concentrations promoted SH similar to the commercial positive control, both being significantly higher than the LFD without TMP and Placebo (p < 0.001).ConclusionThe supplementation of LFDs with TMP is able to significantly increase the anti-erosive potential of these formulations in vitro.