Effect of sodium, amine and stannous fluoride at the same concentration and different pH on in vitro erosion

This study aimed to compare the effects 0.5% and 1% sodium, amine and stannous fluoride at different pH on enamel erosion in vitro.

Bovine enamel samples were submitted to a cyclic de- and remineralisation for 3 days. Each day, the samples were exposed for 120 min to pooled human saliva and subsequently treated with one of the fluoride solutions for 3 min: amine fluoride (AmF, 0.5% and 1% F(-)), sodium fluoride (NaF, 0.5% and 1% F(-)), each at pH 3.9 and 7.0, and stannous fluoride (SnF(2), 0.5% and 1% F(-)), at pH: 3.9. Additionally, two groups were treated with fluoride-free placebo solutions (pH: 3.9 and 7.0) and one group served as control (no fluoridation). Ten specimens each group were inserted in a so-called artificial mouth and eroded six times daily with hydrochloric acid (pH 2.6) for 90 s each intermitted by exposure to artificial saliva (1h). After 3 days, enamel loss was analyzed profilometrically and evaluated statistically by ANOVA.

Only the acidic 0.5% and 1% SnF(2) and 1% AmF solutions were able to reduce erosive enamel loss significantly, while all other solutions and placebos did not differ significantly from the control. Between the acidic SnF(2) and the 1% AmF solutions no significant differences could be detected.

At the same concentrations, acidic SnF(2) and AmF may be more effective than NaF to protect enamel against erosion.