Effect of added calcium phosphate on enamel remineralization by fluoride in a randomized controlled in situ trial

Dental products containing calcium phosphate and fluoride are claimed to enhance enamel remineralization over fluoride products. Objectives: To compare remineralization of enamel subsurface lesions by dental products with added calcium phosphate in a double-blind, randomized, cross-over in situ study. Methods: Human enamel specimens with subsurface lesions were prepared and inserted into intra-oral appliances worn by volunteers. A slurry (1 g product plus 4 ml H2O) of each product was rinsed for 60 s, 4 times per day for 10 days. Six products were tested (i) placebo, (ii) 1000 ppm F, (iii) 5000 ppm F, (iv) Tooth Mousse (TM), (v) TM plus 900 ppm F (TMP) and (vi) Clinpro with 950 ppm F. Calcium, inorganic phosphate and fluoride levels were measured in post-rinse/saliva samples using ion chromatography. Mineral content was measured using transverse microradiography. Results: Only TM and TMP significantly increased salivary calcium and phosphate levels. The products produced remineralization in the following order from lowest to highest: placebo < 1000 ppm F = Clinpro < 5000 ppm F < TM < TMP. Conclusion: Clinpro was not significantly different to 1000 ppm F whereas TM and TMP were superior to 5000 ppm F with TMP producing the highest level of enamel lesion remineralization. (C) 2011 Elsevier Ltd. All rights reserved.