Prevention by means of fluoride of enamel erosion as caused by soft drinksand orange juice

Fluoride has been suggested to prevent erosion of the teeth, either after a topical treatment of the teeth or by addition of fluoride to the acidic dr ink. The main aim of the pre!;ent study was to describe the dissolution of calcium fluoride in some soft drinks and orange juice and compare it with t he amounts of calcium fluoride left on the enamel surfaces after a topical treatment. A further aim was to describe the dissolution of enamel in soft drinks and juice saturated for 3 days with solid calcium fluoride. Solid ca lcium fluoride was suspended in each of 10 soft drinks and orange juices an d gently agitated for 72 h, after which the drinks were analyzed for calciu m, phosphate and fluoride and pH was determined. To examine the erosion-pre ventive effect of the calcium fluoride-rich drink, intact teeth were expose d to the drinks with or without calcium fluoride. It was found that from 6 to 45 mg of calcium fluoride was dissolved per liter of drink. The more aci dic the drink, the more calcium fluoride was dissolved, presumably due to H F formation. The teeth exposed to the soft drinks all showed erosion-like l esions. Very little effect of the 4-6 ppm ionic fluoride dissolved in the s oft drinks was observed, In orange juice, however, the dissolved calcium fl uoride established a saturation with respect to fluorapatite and consequent ly, the erosion-like lesion was replaced by a caries-like lesion. In conclu sion, the acidic soft drinks are capable of dissolving considerable amounts of calcium fluoride and the erosion-preventive effect of even high fluorid e concentrations is limited. Copyright (C) 2001 S. Karger AG. Basel.