Methods for administration of a substantially non-cytotoxic chlorine dioxide composition to whiten a tooth surface are provided. The method comprises contacting a surface of a tooth with an efficacious amount of a composition comprising chlorine dioxide to provide an efficacious amount of chlorine dioxide to the tooth surface, wherein the contacting step comprises one or more of: i) contacting the tooth surface iteratively with at least two, substantially contiguous applications of a substantially non-cytotoxic composition comprising chlorine dioxide; ii) irrigating the tooth surface using an irrigation device that delivers a substantially non-cytotoxic composition comprising chlorine dioxide, or iii) irrigating the tooth surface using an irrigation device that comprises a chlorine dioxide composition comprising a cytotoxic amount of oxy-chlorine anions; and an oxy-chlorine anion barrier, wherein the irrigation devices delivers a substantially oxy-chlorine anion free chlorine dioxide composition to the tooth surface.