The effects of adding chlorhexidine and polyhexamethylene bisguanide to a light-cured periodontal dressing material.

The effect of adding two bisguanide antimicrobial agents (chlorhexidine and PHMB) on some physical properties of the light-cured periodontal dressing material Barricaid are reported. The physical properties tested were elastic modulus, initial and 10 min recovery strains, and tear stress. The addition of both chlorhexidine and PHMB solutions reduced the elastic modulus as did water. The addition of PHMB to Barricaid produced greater initial recovery in the strain test than either the addition of chlorhexidine or water, but there were no differences between the treatments after 10 min. Tear stress was also reduced by the addition of water and the chlorhexidine and PHMB solutions. These results suggest that as far as the physical properties of Barricaid are concerned the addition of the antimicrobial agent PHMB had no long-term advantages over chlorhexidine.