Diffusion Controlled Dissolution and Precipitation

Dissolution and precipitation reactions that occur in biological systems and in non-stirred in vitro systems generally are diffusion-controlled. Subsurface demineralization of tooth enamel in dental caries, which has been the subject of considerable interest, is an example of such processes. In the caries process ions from solubilized tooth mineral, i. e., Ca, P04, and OH, need to be transported from the lesion below the tooth surf\u27ace to the plaque and eventually into the saliva