Protective Efficacy of Toothpastes in Erosive Enamel Wear

Objectives: To evaluate the protective efficacy of a toothpaste containing calcium silicate and sodium phosphate salts plus fluoride in erosive enamel wear compared to fluoride control toothpaste formulation.
Methods: Well-polished bovine tooth enamel specimens with similar baseline mechanical properties were subjected to erosive wear treatment. Specimens were partially covered by nail varnish as the reference and then sequentially treated by toothpaste slurry brushing (toothpaste: water, 1:2), artificial saliva soaking (37°C, ≥ 3 h) and acidic erosion (1% citric acid, pH=3.6, 2 min) within 1 cycle. Samples (n=9) were treated by two toothpastes: (1) silica toothpaste containing 1450ppm F as sodium monofluorophosphate (SMFP), and (2) toothpaste containing calcium silicate and sodium phosphate salts plus 1450ppm F as SMFP. Surface profilometer measured depth change across reference and experimental areas after 14 cycle treatment; surface microhardness was measured after 7 and 14cycles of treatment.
Results: The mean (S.D.) values in depth of mineral loss and surface microhardness are shown in the table. Enamel treated by Toothpaste 2 showed significantly less mineral loss and higher microhardness than that of Toothpaste 1 (paired t-test) under the same conditions.
Conclusions: The toothpaste containing calcium silicate and sodium phosphate salts plus fluoride gave greater structural and mechanical protection against erosive enamel wear than the fluoride control toothpaste.