Erosion-inhibiting potential of a stannous chloride-containing fluoride solution under acid flow conditions in vitro

ObjectivesThis study aimed to analyse the erosion-inhibiting potential of a single application of stannous chloride-containing fluoride solution on pellicle-covered enamel and dentine under constant acid flow conditions in vitro.DesignBovine enamel (n = 60) and dentine (n = 60) samples were exposed 1 h to the oral cavity of 4 healthy volunteers to allow for in situ pellicle formation. Pellicle-covered samples were randomly assigned to three groups (each n = 20 enamel and n = 20 dentine samples; 5 enamel and 5 dentine samples/volunteer) and treated once with a SnCl2/AmF/NaF (800 ppm Sn(II), 500 ppm F, pH 4.5) or a NaF solution (500 ppm F, pH 4.5) for 2 min or remained untreated (controls). Samples were eroded with hydrochloric acid (pH 2.6) in a small erosion chamber at 60 μl/min for 25 min. Calcium release into the acid was monitored in consecutive 30 s intervals for 5 min, then at 1 min intervals up to a total erosion time of 25 min using the Arsenazo III procedure. Data were statistically analysed by random-effects linear models (p < 0.05).ResultsThe stannous chloride-containing fluoride solution reduced calcium loss of enamel and dentine to up to 6 min and 3.5 min, respectively. Calcium loss (% of control) amounted from 24 ± 7 (30 s) up to 93 ± 14 (6 min) in enamel and from 38 ± 13 (30 s) to 87 ± 15 (3.5 min) in dentine. The sodium fluoride solution was unable to reduce enamel and dentine erosion at any time point.ConclusionA single application of a stannous chloride-containing fluoride solution reduced enamel and dentine erosion up to 6 min and 3.5 min of constant acid flow, respectively.