The caries decline: is the effect of fluoride toothpaste overrated?

A method of incorporating an additive or dopant oxide in a glass body produced by the flame hydrolysis technique. Particles of the primary glass former are produced by flame hydrolysis and deposited to form a porous body. This is impregnated with a vaporized dopant which condenses within the pores on cooling. The body is then thermally consolidated with the dopant dispersed therein.