INTERACTION OF ZINC WITH A SYNTHETIC CALCIUM-PHOSPHATE MINERAL

As zinc has been included in several oral health products as an antica lculus and antiplaque agent, the interaction of zinc with a synthetic phosphate was investigated. The synthetic calcium phosphate used in th is study was beta-tricalcium phosphate, or whitlockite, which is a maj or constituent of mature calculus. The aim of this work was to study t he mechanism of uptake of zinc to this mineral. Zinc was readily taken up by the calcium phosphate to a maximum level of 13.9 mu mol/m(2). T he interaction was reversible and followed a Langmuir adsorption isoth erm. There was no concomitant release of calcium with zinc uptake. Inc lusion of calcium in the exposure solution did however marginally depr ess the acquisition of zinc (12% max), but fluoride had no significant effect on uptake.