The effects of inorganic ions situated at the enamel surface on the adsorption and activity of acid phosphatase.

This study has demonstrated, first, that the affinity of the enamel surface for a biologically active protein-in this case, acid phosphatase-may be modified by first impregnating the mineral with particular inorganic ions. Second, enzymic activity is altered as a function of the inorganic ion incorporated into the enamel surface. Third, strong inhibition of acid phosphatase is demonstrated by ions expected to be released during the carious process which contradicts the postulation that phosphatases are actively hydrolyzing enamel matrix-bound phosphate during the carious attack. Fourth, these results suggest that by incorporating a particular ion into the enamel mineral, a surface with assigned properties may be created which offers some degree of control over subsequent adsorption of organic matter. Thus, it is apparent that by proper selection of inorganic ions and organic macromolecules, both structural properties and biological activities at the enamel-oral fluid interface may be predictably modified.