Effect on dental plaque formation and some in vitro properties of 12 bis-biguanides.

Abstract

Six alkyl‐, 4 alicyclie‐ and 2 aryl‐bis‐biguanide formulations have been tested for plaque inhibition in vivo. The participants refrained from mechanical oral hygiene for 3 days while they employed aqueous lest solutions as mouthrinses twice daily. During the experimental period the plaque formation was enhanced with frequent sucrose rinses. The antibacterial activity, the toxicity in cell cultures and the affinity for proteins of the same compounds were also studied. All the test agents showed plaque inhibitory capacity, most of them on a level comparable to that of chlorhexidine. There was a trend towards correlation between antibacterial activity, toxicity in cell cultures, and plaque inhibition. The affinity of the compounds for bovine albumin seemed to be pH‐dependent, thus indicating an electrostatic affinity between the bis‐biguanides and protein. It has been suggested previously that protein‐drug interaction might be an important aspect of the mechanism of chlorhexidine retention in the mouth. Discoloration of teeth and silicate fillings were frequently observed.