Antimicrobial and antiplaque effects of a chlorhexidine and Triton X-100 combination

This study aimed to assess the in vitro antimicrobial effect and in vivo plaque-inhibiting capacity of chlorhexidine (CH) combined with the nonionic detergent Triton X-100. Synergistic inhibition was observed by the combination of Triton X-100 and CH on in vitro growth of S. sobrinus OMZ 176 and of S. sanguis 10556. In the clinical experiments, 10 subjects rinsed twice daily with 10 ml aqueous solutions of 11.6 mM Triton X-100, and 0.55 mM CH, and with a combination of the two agents. All mechanical oral hygiene was suspended during the test periods. Sucrose enhanced plaque accumulations were recorded after 4 days of rinsing. The combination of CH-Triton X-100 decreased plaque accumulations significantly compared to placebo, but was less effective than CH alone (P less than 0.05). Thus no beneficial clinical effect was gained by combining the nonionic agent Triton X-100 with the cationic agent CH. The results also clearly demonstrate that addition which increase the antibacterial activity of CH do not necessarily coincide with improved in vivo antiplaque efficacy.