Zinc citrate/Triclosan: a new anti-plaque system for the control of plaque and the prevention of gingivitis: short-term clinical and mode of action studies.

A dentifrice based upon the additive anti-plaque effects of zinc citrate and Triclosan has been developed and optimised for clinical activity. In 16-h and 4-day plaque growth inhibition studies, zinc citrate/Triclosan inhibited plaque accumulation significantly more than either agent alone. The effect on the development of gingivitis has been demonstrated in a 21-day experimental gingivitis study. ZCT/Triclosan reduced the development of gingival bleeding sites by significantly more than ZCT alone, suggesting that the system has the potential to give a gingival health benefit in a 6-month unsupervised brushing study. Zinc and Triclosan employ multiple modes of antimicrobial action and these result in reduced growth, inhibition of glucose uptake and metabolism and modified virulence of periodontal pathogens. Importantly, the effects of zinc and Triclosan are additive and complementary. Oral substantivity is a pre-requisite of any agent for anti-plaque activity in vivo. Pharmacokinetic data demonstrate that approximately 30% of the zinc and Triclosan dosed is retained immediately after brushing. Saliva decay curves indicate that Triclosan is cleared more quickly from the mouth than zinc, consistent with the physicochemical properties of these agents. Triclosan is present in plaque for at least 8 h and in the oral mucosa for at least 3 h after brushing.