Efficacy of tin-containing solutions on erosive mineral loss in enamel and dentine in situ

Abstract

The addition of tin to mouth rinses is, at least in vitro, a promising strategy for symptomatic therapy of dental erosion. The aim of this study was to evaluate the in situ efficacy of an experimental tin-containing fluoride solution on erosive tissue loss in human enamel and dentine. The study was a three-cell (7days each) crossover design involving eight healthy participants. Samples were mounted on buccal shields of mandibular mouth appliances, which were worn for 24h except during meals and drinks. Specimens were demineralised extraorally with 0.05M citric acid (pH 2.3) for 6 × 5min daily and were treated with test solutions intraorally once per day for 30s after the first demineralisation. Three solutions were used: placebo (negative control), a commercially available tin- and fluoride-containing (SnF(2)) mouth rinse (positive control, 409ppm Sn(2+), 250ppm F(-), pH 4.2) and an experimental solution (pH 4.5) containing 1,900ppm Sn(2+) (SnCl(2)) and 1,000ppm F(-) (AmF/NaF). Tissue loss (micrometre) was determined profilometrically. In enamel, tissue loss was 54.8 ± 8.6 in the placebo, 24.5 ± 14.4 in the positive control and 9.7 ± 4.1 in the experimental solution group. The respective values for dentine were 48.5 ± 13.0 in the placebo, 32.8 ± 9.6 in the positive control and 26.2 ± 6.7 in the experimental solution group. The experimental solution was notably effective for enamel but was less effective for dentine. The positive control solution was less effective than the experimental solution; its effects for enamel and dentine were similar.