Protocol for the Assessment of Enamel Erosion and the Effect of a Fluoridated Mouthrinse Containing Nano- Sized Trimetaphosphate Against Erosion

Objectives To develop a protocol for the evaluation of enamel erosion and to evaluate the effect of fluoride mouthrinses associated with nano-sized trimetaphosphate on enamel erosion using an artificial mouth. Material and methods Fifty-three volunteers with high frequency of acid drink consumption were evaluated for duration and interval between sips, as well as the total drinking time. After standardizing the protocol, bovine enamel blocks ( n  = 120) were subjected to erosive cycles three times a day and treated with mouthrinses twice a day (1 min): placebo, 100 ppmF, 225 ppmF, 100 ppmF + 0.2% micrometric TMP and 100 ppmF + 0.2% ano-sized TMP. The blocks were analyzed by profilometry, surface hardness and cross-sectional hardness after 1 or 3 days. Data were submitted to two-way ANOVA, followed by Student-Newman-Keuls' test, and Pearson correlation ( p  < 0.05). Results Most volunteers were women (74.4%) with a mean age of 21 years. Among all volunteers, 35.9% preferred to consume juices. Median sip time was 3.4 s, with a pause of 6.4 s and a total drinking time of 1 min and 10 s. Mouthrinses containing TMP showed the greatest protective effect against enamel hardness loss and wear, with additional benefit from the use of nanoparticles. Conclusions The protocol developed using an artificial mouth is informative and suitable for studying erosive tooth wear under in vitro conditions. Treatment with mouthrinses containing TMP significantly reduced enamel erosive wear and mineral loss. Clinical Relevance: TMP supplementation in mouthrinses significantly enhances their protective effect against erosive enamel wear.