ORGANIC-SOLVENTS AND OILS AS VEHICLES FOR TRICLOSAN IN MOUTHRINSES - A CLINICAL-STUDY

Previous experiments have shown that the nature of the detergents used in aqueous triclosan-containing mouthrinses affects the plaque-inhibi ting effect of these mouthrinses, probably because of the properties o f the micelles formed. It has also been shown that triclosan has a mar ked plaque-inhibiting effect when dissolved in pure propylene glycol. The aim of the present study was to compare the clinical effect of tri closan dissolved in oils and in the pure solvents glycerol (GLY) and p olyethylene glycol (PEG). A test panel of 12 volunteers rinsed with th e allocated mouthrinses for 4 days in a double-blind, crossover study. Three different oils were tested: olive oil, soy oil, and sunflower s eed oil, as well as PEG and GLY. Triclosan was used in a 0.3% concentr ation to facilitate comparison with previous studies. However only 0.1 5% triclosan was added to the GLY-containing rinse (maximum soluble co ncentration). In addition, soy oil without triclosan was tried. The me an plaque score for water was 1.42 +/- 0.19; for olive oil, 1.08 +/- 0 .34; for soy oil with triclosan, 0.95 +/- 0.35; for pure soy oil, 0.94 +/- 0.09; for sunflower seed oil, 1.19 +/- 0.19; for PEG, 1.04 +/- 0. 22; and for GLY, 1.12 +/- 0.28. The results indicate that triclosan di ssolved in oils loses its clinical effect. However oils in themselves exhibit significant plaque inhibition. In vitro tests showed no antiba cterial activity of triclosan dissolved in oils. Toothpastes and mouth rinses contain flavoring oils and occasionally also GLY and PEG. Such substances may well interfere with the clinical effect of triclosan in these products. This study shows that GLY and PEG are not well suited as vehicles for triclosan in dental products.