A quantitative radiochemical study of ionic and molecular transport in bovine dental enamel

A radiochemical method was developed to determine quantitatively and simultaneously the transport of up to four different compounds through dental enamel. The compounds chosen were [3H]-sorbitol, [14C]-glycerol, 36Cl- and 86Rb+. Effective diffusion coefficients of these compounds determined at 40C were considerably different for different specimens of enamel. Thus values for [3H]-sorbitol varied for 0.04 x 10-8 to 2.5 x 10-8 cm2s-1. Most enamel membranes showed an ion selective behaviour by which the cations were more mobile than the anions. A molecular sieve effect was observed for glycerol and sorbitol. (author)