Review of the current status of tooth whitening with the walking bleach technique.

Internal bleaching procedures such as the walking bleach technique can be used for whitening of discoloured root-filled teeth. The walking bleach technique is performed by application of a paste consisting of sodium perborate-(tetrahydrate) and distilled water (3% H2O2), respectively, in the pulp chamber. Following a critical review of the scientific literature, heating of the mixture is contra-indicated as the risk of external cervical resorption and the formation of chemical radicals is increased by application of heat. An intracoronal dressing using 30% H2O2 should not be used in order to reduce the risk of inducing cervical resorption. This review provides advice based on the current literature and discusses how the walking bleach technique can lead to successful whitening of non-vital root-filled teeth without the risks of side-effects.