[Development and evaluation of an active substance controlled-release device for use in the oral cavity].

In order to improve drug administration for diseases of the oral cavity, we have developed an intraoral controlled release delivery system enabling local concentrations high enough for desirable therapeutic effect with minimal side effects. We have formulated 200 mg tablets to be fixed on a tooth. These tablets resist attacks by food and beverages. The tablets have a granular matrix composed of hydroxyapatite, ethyl cellulose and Eudragit. Zinc sulfate, which has a therapeutic effect on the buccal mucosa was used as the first model of an active drug. Profiles of continuous in vitro drug release in distilled water at 37 degrees C show that zinc sulfate release by the matrix structure for the different tablet formulations is regulated by the proportions of the different components.