Calcium Fluoride and Fluoridated Hydroxyapatite Formation in Relation to the Acid Dissolution Rate of Enamel Mineral

Abstract

Hydroxyapatite (HA) discs were treated for 1 min with fluoride solutions of varying concentrations and pH. The calcium fluoride and fluoridated hydroxyapatite (FHA) formed were analysed independently of each other following their separation in molar potassium hydroxide. Only the more intimately associated FHA was found to affect the rate of acid dissolution of HA and its level of formation and the reduction in acid dissolution rate of HA were both found to be linearly related to the logarithm of the ionic fluoride level in the treatment solution following 1 min. pretreatment. The benefit of using acidulated fluoride treatment of enamel is questioned as neutral fluoride treatments of enamel mineral resulted in equivalent protection.