It has been suggested that
fluoride products are able to reduce erosive
tooth wear. Thus, the purpose of this in vitro study was to evaluate the effect of
dentifrices with different
fluoride concentrations as well as of a low-fluoridated
dentifrice supplemented with trimetaphosphate (
TMP) on enamel erosion and abrasion. One hundred twenty bovine enamel blocks were assigned to the following experimental
dentifrices: placebo, 1,100 microg F/g, 500 microg F/g plus 3%
TMP and 5,000 microg F/g. The groups of enamel blocks were additionally subdivided into conditions of erosion (ERO) and of erosion plus abrasion (ERO + ABR). For 7 days, the blocks were subjected to erosive challenges (immersion in Sprite 4 times a day for 5 min each time) followed by a remineralizing period (immersion in
artificial saliva between erosive challenges for 2 h). After each erosive challenge, the blocks were exposed to slurries of the
dentifrices (10 ml/sample for 15 s). Sixty of the blocks were additionally abraded by brushing using an electric toothbrush (15 s). The alterations of the enamel were quantified using the Knoop hardness test and profilometry (measurements in micrometers). The data were analyzed using a 2-way ANOVA test followed by a Bonferroni correction (p < 0.05). In in vitro conditions, the 5,000 microg F/g and 500 microg F/g plus 3%
TMP dentifrices had a greater protective effect when compared with the 1,100 microg F/g
dentifrice, under both ERO and ERO + ABR conditions. The results suggest that
dentifrices alone are not capable of completely inhibiting
tooth wear.