Solubility changes of human enamel treated with precipitate-free, aged SnF2/amine fluoride 297 solutions

Enamel specimens were immersed in fluoride solutions (250 ppm F) containing either freshly mixed SnF2 or aged precipitate-free aqueous solutions of SnF2 and amine fluoride 297 (AmF 297) at molar ratios of 3:1, 1:1: or 1:3, respectively. After the specimens were treated, the enamel treated with SnF2 in the SnF2/AmF 297 solutions.