Delmopinol - adsorption to and absorption through the oral mucosa.

OBJECTIVES: To investigate the surface chemical changes in dynamic interactions of delmopinol on salivary films on oral mucosa in healthy participants after rinsing with an unbuffered water solution of delmopinol, and to examine the oral tissue disposition of delmopinol in rats after local administration. MATERIAL AND METHODS: The contact angle technique was used to monitor the interaction of delmopinol with the salivary film coating the upper labial mucosa of 10 healthy participants through a 4 h period. The tissue disposition of 14C-labelled delmopinol was examined in rats by autoradiography. RESULTS: Rinsing with delmopinol increased the polarity of the saliva coated mucosa during the time of observation. The binding of delmopinol was verified in the autoradiograms showing that radioactivity remained in the rat oral mucosa after 24 h. Delmopinol was however not irreversibly bound. CONCLUSIONS: The findings indicate that delmopinol interacts with the salivary film of the upper labial mucosa and affects its polarity. It appears that delmopinol assists in the maintenance of the hydrophilicity of the mucosal pellicle and thereby also reinforcing hydration of the mucosa. The rat autoradiograms, showed that radioactivity remains in the oral mucosa after 24 h, but diffuses through the mucosal membranes into the systemic circulation.