However, a judgment of usual amount of toothpaste used may be an overly crude dose measure across an 8-year span, especially given that only 10 percent of the subjects were reported to have usually used a pea-sized amount of toothpaste, which has only recently become the recommended amount for use by preschool children (5). The role of this variable merits further study as the proportion of children who use a pea-sized amount increases in the years ahead.