Effect of chlorhexidine on the adherence properties of Porphyromonas gingivalis.

Chlorhexidine is a bisbiguanide compound that possesses substantive and antibacterial properties. The aim of the present investigation was to evaluate the effect of chlorhexidine on the adherence of Porphyromonas gingivalis to epithelial cells and erythrocytes. Both pretreatment of bacterial cells with chlorhexidine (> 20 micrograms/ml) and incorporation of chlorhexidine in an adherence assay markedly affected the ability of P. gingivalis to adhere to epithelial cells. Chlorhexidine also strongly inhibited hemagglutination by P. gingivalis. It is suggested that chlorhexidine binds to cells, altering the structural conformation of the outer membrane and reducing adherence. This ability of chlorhexidine to prevent bacterial adherence may represent an additional mechanism by which this antimicrobial agent exerts its beneficial clinical effect when used as an adjunct to periodontal therapy.