A comparison of triclosan and stannous fluoride toothpastes for inhibition of plaque regrowth. A crossover study designed to assess carry over.

Some triclosan and stannous fluoride toothpastes have been shown effective in reducing plaque and more particularly gingivitis in home use studies. There have been few comparisons of such products for their chemical plaque inhibitory action divorced from the indeterminate variable of toothbrushing. This study was a randomised, single-blind, cross-over comparison of 4 products, in a 4-day plaque regrowth design, balanced for residual effects and involving 12 healthy dentate subjects. The test agents were a stannous fluoride toothpaste, a triclosan/copolymer toothpaste, a triclosan/zinc citrate toothpaste and water. On day 1 of each study period, subjects were rendered plaque free. For the following 4 days, each subject suspended normal toothcleaning and rinsed 2 x daily with the allocated treatment for 60 s under supervision. On day 5, plaque was scored by index. Washout periods of 2 1/2 days brushing with water alone, followed each treatment period. Pseudo treatment periods of 4 days, involving 2 x daily rinsing with water in the absence of toothbrushing, followed the normal washouts after the stannous fluoride and triclosan/zinc citrate treatments, giving a total of 6 treatment periods. This design permitted analyses for 1st-order-carry-over. Intention to treat analyses revealed all toothpastes were more effective than water but that there were no differences between the active treatments. Per protocol analysis gave essentially similar findings except that the difference in plaque in favour of the triclosan/zinc citrate toothpaste over water did not reach significance. There was no evidence of 1st-order-carry-over effects for the stannous fluoride or triclosan/zinc citrate toothpastes. Consistent with other studies it appears that stannous fluoride and triclosan can be formulated into toothpaste vehicles to provide plaque inhibitory effects.