The antibacterial agent triclosan has demonstrated antiplaque and antigingivitis activity in several clinical studies. Retention of antiplaque agents is of significance for their clinical effect. Triclosan has a relatively rapid clearance from the oral cavity, and attempts have been made to increase its oral retention. In the present clinical antiplaque study, it was found that 0.5% copolymer polyvinyl-methylether maleic acid (PVM-MA) or 0.5% zinc citrate, which are both added to commercial products, inhibited plaque formation to a similar degree when used in combination with 0.3% triclosan, 1.5% sodium lauryl sulfate (SL.S) and diluted propylene glycol (PG) in water (18). Plaque inhibition was significantly improved compared to a placebo solution. It was shown that these results could not be explained by an increase in antibacterial activity or by a change in the critical micellar concentration. The effect of the same solutions on SLS-induced inflammation on skin was also tested. It was seen that the triclosan/ zinc citrate solution and the control (triclosan/ethanol) decreased the inflammatory response, whereas the solutions containing triclosan in either propylene glycol (PG) or copolymer/PG did not exhibit any anti-inflammatory capacity.