The Effect of Sodium Fluoride on the Solubility of Calcium Phosphate, Tooth Enamel and Whole Teeth in Lactic Acid

Abstract

The addition of small amts. of NaF to solns. of lactic acid reduces the apparent solubility of Ca phosphate and powdered tooth enamel in the acid. The high phosphate and low Ca values for the supernatants indicate that the apparent lowering in the solubility caused by the fluoride is due to the precipitation of Ca fluoride. Na oxalate has an analogous effect. The inhibitory effect of Na fluoride and Na oxalate on in vitro decalcification of teeth by lactic acid at pH values below 4 may be due to the same process proceeding at a slower rate.