Effects of toothbrush size and dentifrice type/brand on pea-sized and larger amounts of dentifrice

Abstract

To assess the effects of toothbrush size and dentifrice type/brand on amounts of dentifrice being placed when trying to replicate pictures with different amounts of dentifrice, including a pea-sized amount. This laboratory trial used one researcher to repeatedly dispense five dentifrice products on three different child-sized toothbrushes using a standard procedure. Two sets of drawings, depicting the recommended pea-sized and larger amounts, were used as guides in an effort to place the same amount each time. Data were analysed using ANOVA. Amounts of dentifrice placed on the two larger toothbrushes were significantly greater than those placed on the smallest toothbrush (p < 0.0001). The amounts placed on the two larger toothbrushes with similar brushing areas but different shapes were not significantly different from each other. The effect of dentifrice type/brand varied in each analysis. For pea-sized amounts, one of 10 pairwise comparisons was significant. For amounts larger than pea-sized, another pair of the 10 pairwise comparisons was significant. However, there was no significant effect of dentifrice type/brand when considering both pea-sized and larger amounts together in the same analysis. Toothbrush size significantly affected the amount of dentifrice placed for both pea-sized and larger amounts. The amounts placed on larger size toothbrushes were greater than on the smaller size toothbrush. No consistent effects of selected dentifrices were found.