Bentley and colleagues tested British mothers' interpretation of instructions to apply smear and pea-sized amounts of low and high-concentration fluoridated toothpastes packaged in tubes with special nozzles. They found that mothers applied less toothpaste
when asked to apply a smear (0.22 g) than when asked to apply a pea-sized quantity (0.30 g). Responses to the smear instruction resulted in wider variability than the instruction to apply a pea-sized amount.*" A subsequent study, conducted in the United
States by Levy and colleagues,'"* confirmed Bentley's findings that parents typically exceed the recommend dose of fluoridated toothpaste.
In the Levy study, parents administered an average of 0.31 g of toothpaste in response to the pea-sized instruction.''' The researchers did not test parents' responses to apply a smear amount.