The Additional Effect of a Dentifrice on the Instant Efficacy of Toothbrushing: A Crossover Study

Background: Inconclusive evidence exists in the literature with regard to the additional (beneficial) mechanical effect of a dentifrice on plaque removal. A previous split‐mouth study found that a dentifrice did not contribute to plaque removal. Because of limitations of the split‐mouth model, a crossover design was used to evaluate whether a commercially available dentifrice had an additional effect on mechanical plaque removal during manual toothbrushing. Methods: Thirty‐six subjects were given a manual toothbrush and a standard dentifrice. After a 48‐hour plaque accumulation, subjects brushed under supervision with or without a dentifrice (total time of 2 minutes) in a 2 × 2 crossover design. Results: Plaque reductions were 50% with and 56% without the use of dentifrice. This 6% difference was statistically significant (P = 0.034). Explorative analysis showed that brushing without a dentifrice was more effective in removing plaque on the approximal surfaces. Conclusions: The use of a dentifrice did not contribute to mechanical plaque removal during manual toothbrushing. It seemed that the mechanical action provided by the toothbrush was the main factor in the plaque‐removing process.