Introduction. Alginate impression material has the potential to act as a controlled release material, either for trans-mucosal drug delivery, or for use as a self-disinfecting impression material in clinical dentistry. Aim of the study. To study whether sodium fusidate could be released from alginate impression material and, if so, to determine the release kinetics. Material and methods. Sodium fusidate was incorporated into alginate impression material at the mixing stage (2% by mass). The mixed material was pressed into a sheet and, once cured, discs (6 mm diameter x 2 mm thick) were cut out, and stored in water, one disc in a 5 ml volume. Small samples (20 µl) were withdrawn at time intervals of 1, 2, 3, 4, 5, 24 h, 1, 2 and 3 weeks and analysed by HPLC. Results. Sodium fusidate was released from the impression material in a process that was shown to be diffusion based for the first 5 hours or so. The diffusion coefficient was 2.25 x 10–5 cm2 s-1, and the release corresponded to 36.0 ± 1.0% of the total loading. The system thus shows promise for clinical application.

Key words: alginate, impression material, sodium fusidate, controlled release.