The solubility of fluorapatite and its relationship to that of calcium fluoride

Tables of solubility (mg/l) are given for FA and CaF2 at pH 4–7.5 showing the influence of ionic strength, and added F, P, and Ca. The solubility of CaF2 was shown to be 12–15 mg/l in saliva, whereas FA was essentially insoluble. It is concluded that the mechanism of action of F in caries inhibition is related to this stability of FA.