Using fluoride mouthrinses before or after toothbrushing: effect on erosive tooth wear.

OBJECTIVES: 1. To evaluate the use of fluoridated mouthrinses before or after toothbrushing on erosive tooth wear. 2. To compare the anti-erosive effect of the combination toothpaste and mouthrinse containing fluoride, with or without stannous chloride. DESIGN: Enamel and dentin specimens were randomly distributed into groups (n = 10 of each substrate/group): B-brushing, B + R-brushing + rinsing, and R + B-rinsing + brushing. The treatments were performed using a fluoride toothpaste (BF: 1400 ppm fluoride, as amino fluoride-AmF) combined or not with a fluoride mouthrinse (RF: 250 ppm fluoride, as AmF and sodium fluoride-NaF) or fluoride and stannous toothpaste (BF+Sn: 1400 ppm fluoride, as AmF and NaF, 3500 ppm stannous, as stannous chloride-SnCl2 and 0.5% chitosan) combined or not with fluoride and stannous mouthrinse (RF+Sn: 500 ppm fluoride, as AmF and NaF, 800 ppm stannous, as SnCl2). As control, brushing was performed with artificial saliva (BC). Specimens were submitted to a 5-day erosive-abrasive cycling model. Treatments were performed twice daily. Surface loss (SL) was determined by optical profilometry. Data were analyzed by ANOVA and Games-Howell tests (α = 0.05). RESULTS: For enamel, RF+BF and RF+Sn+BF+Sn presented significantly lower SL than the control, with RF+BF being significantly lower than RF+Sn+BF+Sn. For dentin, BC had the lowest SL, not differing from BF+Sn+RF+Sn, RF+Sn+BF+Sn and BF. Groups RF+BF and BF+RF showed highest SL, not differing from BF+Sn and BF+Sn. CONCLUSIONS: For enamel, the use of a mouthrinse before brushing was able to reduce erosive wear for both fluoride and stannous products. For dentin, the use of stannous-containing products, irrespective of the order of application, presented superior effects.