A method for whitening a dental surface comprises nonsimultaneously applying a whitening composition to the surface, the whitening composition comprising at least one orally acceptable peroxy compound, and directing a volume of up to about 2.5 ml of an atomized activating composition on to the surface, wherein the activating composition comprises, in the volume so directed, a peroxy compound activating effective amount of at least one orally acceptable basifying agent, and wherein applying the whitening composition and directing the activating composition are separated by an interval not greater than a peroxy compound activating effective interval. The atomized composition can be directed on to the dental surface before or after application of the whitening composition.