Abstract: Electrochemical method for treating teeth: applying metal salt solution to teeth, applying ionizable substance to the teeth, and applying current flow to the teeth so as to ionize the ionizable substance. Electrochemical device for dental treatment: applicator for applying a substance to teeth, having a first end and a second end, a first electrode attached to first end of applicator, second electrode attached to second end of applicator, wherein first electrode and second electrode are configured for current flow through applicator, and an ionizable substance for placement within applicator, wherein ionizable substance is configured for ionization upon application of current flow through the substance. Electrochemical teeth whitening method: applying metal salt solution to teeth, applying an oxidizing agent to teeth exposed to metal salt solution, and applying current flow to the teeth so as to activate and reduce the oxidizing agent for effecting whitening of the teeth.