Comparative efficacy and safety of chemical and physicochemical tooth whitening

The review addresses different chemical and physicochemical tooth whitening methods, with a focus on their efficacy, safety, and potential side effects.

Chemical tooth whitening involves oxidizing pigments in the enamel and dentin with hydrogen peroxide and urea. Despite their high efficacy, long-term use of chemical whitening agents may cause microstructural changes in the enamel, reducing its microhardness and increasing porosity.

Physicochemical tooth whitening techniques, such as lasers and light-emitting diodes, activate low concentrations of whitening agents, decreasing the risk of enamel damage and tooth hypersensitivity. The rate and degree of tooth whitening may vary depending on the concentration of active components and the exposure time. According to the studies, higher hydrogen peroxide concentrations provide faster tooth whitening, but are more frequently associated with side effects (including tooth hypersensitivity and irritation of the gingiva and soft oral tissues).

Combination approaches have been shown to significantly reduce discomfort in patients with tooth hypersensitivity. The long-term stability of tooth whitening outcomes is actively studied, because repeated use of chemical whitening agents can promote structural changes in the enamel.