Effect of Remineralizing Agents on Dental Erosion in a Reduced Salivary Flow Population: An in situ Model

Objectives: The purpose of this in situ crossover design study was to compare the remineralization effectiveness of a high concentration fluoride dentifrice and a remineralizing agent used by a patient, with reduced salivary flow after one week of home application period; specifically Prevident 5000 Toothpaste (1.1 %NaF), MI Paste (CPP ACP), and a positive control 1450 PPM Colgate Cavity Protection. Methods: Twenty-one subjects, 11 with reduced salivary flow and 10 with normal salivary flow participated in a double blind crossover design completing 3 arms. In each arm, each participant wore one custom made orthodontic bracket attached to the buccal surface of a mandibular molar containing one slab of demineralized bovine enamel. In one week, subjects completed the treatment regimen brushing twice a day for 1 minute with the test dentifrice, always starting with the 1450 PPM dentifrice. Subjects were randomized to the second two arms to either Prevident or MI paste in combination with 1450PPM fluoride dentifrice. After one week enamel slabs were retrieved and analysed using surface microhardness recovery (SMH). Results: Statistically significant difference was observed (p<0.05) in surface microhardness between the pre and post-test for both salivary flow groups amongst all remineralization treatments. No significant differences in SMH recovery were observed between the reduced salivary flow group and normal salivary flow group (p>0.05). Conclusions: A differential effect of remineralizing agents was not discernible between reduced salivary flow and normal salivary flow subjects on early enamel erosion. A 1,450 PPM fluoride dentifrice alone, and in combination with a 5000 PPM prescription strength fluoride dentifrice and a calcium-based product were able to enhance remineralization in both normal and reduced salivary flow patients with a trend towards better remineralization response for the 5000 PPM fluoride dentifrice.