Hydrogen peroxide decomposition in the oral cavity.

ABSTRACT

PURPOSE: To determine the clearance of hydrogen peroxide from the oral cavity of infants (3-4 yrs of age), juveniles (7-12 yrs of age), adults (35-66 yrs of age), and adults with impaired salivary flow (34-71 yrs of age). MATERIALS AND METHODS: In all subjects, the amount of H2O2 present in the oral cavity was assessed following a 1-min brushing period with an experimental dentifrice formulated with 3% hydrogen peroxide for up to 9 mins postbrushing. In addition, the oral clearance of 3% hydrogen peroxide delivered in an experimental dentifrice formulated with 5% baking soda was determined in a control population of adults and adult subjects with impaired salivary flow. RESULTS: Most of the hydrogen peroxide decomposed during brushing, with less than 30% of the prebrushing dose of hydrogen peroxide remaining in the oral cavity after 1 min of brushing. No differences between infants, juveniles, and adults were seen in levels of hydrogen peroxide recovered from the oral cavity after tooth brushing. When a mixture of hydrogen peroxide and baking soda was used for brushing, less than 5% of the hydrogen peroxide was recovered from the oral cavity after 1 min of brushing. In conclusion, clearance of hydrogen peroxide from the oral cavity was very rapid in children, adults, and adults with impaired salivary flow. Decomposition of hydrogen peroxide was enhanced approximately six-fold in adults by the presence of baking soda in the dentifrice. No substantial amount of hydrogen peroxide survived beyond the brushing period, and very little material would be present to interact with soft tissues in the oral cavity after expectorating any remaining dentifrice containing hydrogen peroxide.