Novel Sodium Fluoride Dentifrice Effects on Early Enamel Erosion in-situ

Objectives: A novel sodium fluoride-silica dentifrice containing lactate and PVM/MA copolymer has been developed to enhance remineralisation and provide resistance to further erosive demineralisation. This in-situ study compared the new dentifrice with a marketed stannous fluoride dentifrice (both 1100-1150 ppm fluoride), and a fluoride-free placebo, using an established erosion model.
Methods: In this single-center, randomized, three-way crossover-design in-situ study, healthy subjects (n=62) wore intra-oral appliances containing eight partially-eroded bovine enamel specimens. Subjects used their allocated dentifrice once: the novel experimental dentifrice (ED); Crest Pro-Health Sensitivity+Enamel Shield (Smooth) (CPH); or fluoride-free placebo (PL). Subjects brushed their natural teeth for 25 seconds, then swished the resulting slurry around their mouth for 95 seconds. Four enamel specimens were removed after 2h intra-oral exposure; four were removed after 4h. Knoop surface microhardness (SMH) was measured pre-demineralisation; post-demineralisation; post-remineralisation; and after a final demineralisation challenge, to calculate %SMH recovery (SMHR), relative erosion resistance (RER), and acid-resistance ratio (ARR). Fluoride uptake (EFU) was also measured.
Results: The table provides study raw mean (SD) %SMHR, RER, ARR and EFU values.

Treatments with the same letter within a time-period were not statistically significantly different from each other (ANOVA model; p>0.05). For SMHR, ED>CPH and ED>PL (both time-points). For RER, EFU and ARR (2h), ED>CPH>PL. For ARR (4h), ED>PL and CPH>PL.
Conclusions: The novel dentifrice enhanced enamel remineralization, fluoride delivery and protection against erosive demineralization versus a stannous fluoride control.