Hydrogen peroxide tooth-whitening (bleaching): review of safety in relation to possible carcinogenesis.

Hydrogen peroxide in the form of carbamide peroxide is widely used in professionally and self-administered products for tooth whitening. Hydrogen peroxide is a highly reactive substance that can damage oral soft and hard tissues when present in high concentrations and with exposures of prolonged duration. This review examines the issue of oral mucosal damage and possible carcinogenicity relating to the use of hydrogen peroxide in the mouth for tooth whitening, with an emphasis on safety with prolonged exposure to low concentrations of peroxide products.