In vitro effect of toothpaste with low fluoride combined with sodium trimetaphosphate on dentine erosion.

Abstract

This study sought to evaluate in vitro the effect of a dentifrice containing sodium trimetaphosphate (TMP) combined or not with low fluoride (500ppm NaF) on dentine erosion of intrinsic origin. Human root dentine blocks were selected based on surface microhardness and randomly allocated into five groups (n = 12): negative control (0 ppmF; no TMP); F500 (500ppm NaF); F1500 (1500ppm NaF-positive control); TMP (1% TMP); and F + TMP (500ppm NaF + 1% TMP). The blocks were submitted to erosion cycles (3×/day) for 3days (0.01M HCl, pH 1.5-30s), treatment (1min-1:3 p/p dentifrice/distilled water) and remineralization (artificial saliva/120min). Dentine alterations were determined according to the percentage of microhardness loss (%HL), surface loss (SL) and surface analysis by scanning electron microscopy. The data were analyzed using one-way ANOVA (p < 0.05). The values of SL and %HL in each group were, respectively: negative control (1.36 ± 0.36; 57.29 ± 14.14), F500 (1.46 ± 0.28; 65.66 ± 5.11), F1500 (1.52 ± 0.36; 61.66 ± 5.15), TMP (1.45 ± 0.45; 62.08 ± 3.83) and F + TMP (1.38 ± 0.42; 63.38 ± 6.47). There was no statistically significant difference in all the parameters (p = 0.873 and p = 0.152). The dentifrices containing TMP combined or not with fluoride were not able to prevent dentine erosion.