Electrochemically whitening of teeth whereby a metal salt solution is applied to the teeth, followed by applying an oxidizing agent to the teeth, and transmitting electrical current to the teeth so as to activate and reduce the oxidizing agent for effecting whitening of the teeth. The device comprises an applicator (100) for applying a substance to the teeth, applicator (100) having a first end (112) and a second end (114), with a first electrode (118), preferably, positively charged, attached to first end (112) and a second electrode (122), preferably, negatively charged, attached to second end (114), configured to transmit electrical current through applicator (100), and an oxidizing agent for placement within applicator (100), wherein the oxidizing agent undergoes activation and reduction upon transmission of the electrical current there through. The oxidizing agent used can be any of a whitening solution, whitening gel, solution or gel of or including any of : hydrogen peroxide, carbamide peroxide, or sodium perborate.