A new model for demonstrating enamel protection benefits relative to acid challenge.

OBJECTIVE: To determine the applicability of a modified US FDA Caries Monograph test method for measuring the protective benefits of fluoride (F) against erosive, dietary acids.

METHODS: Acid-challenged teeth were treated in two studies with a dentifrice, rinsed, and then re-challenged in a series of tests using three dietary acids. Study 1 included dentifrices containing 1450 ppm F as sodium fluoride (NaF) + triclosan [A], 1450 ppm F (NaF) + potassium nitrate (KNO3) [B], 1000 ppm F as sodium monofluorophosphate (SMFP) [C], and 0 ppm F (placebo) [D]. Study 2 included dentifrices containing 1450 ppm F (NaF) [A]; and 0 ppm F (placebo) [B]. Acids were analyzed for phosphate removed during tooth challenges, with post-treatment results compared to baseline. Results were averaged and reported as a % protection value for each product, with higher values indicating greater protection.

RESULTS: Study 1: % protection for A = 16.4; B = 13.0; C = 7.1; and D = -5.2. Study 2: A = 15.2; B = -10.5, with A = B > C > D: Study 1; and A > B: Study 2. In each study, p < 0.05, ANOVA.

CONCLUSIONS: The model provides a viable tool for initially assessing the potential for fluoride-containing oral care products to protect teeth against erosive, dietary acids. This can then lead to further and more elaborate testing with reasonable expectations for outcomes.