Provided is a brush body for selectively applying localized currents, for oral care, to oral interstices such as periodontal pockets. Said brush body has a plurality of bristle bundles in a brush head. A bristle bundle contains a bristle having a core and a sheath. The core comprises a conductive member and the sheath comprises an insulating member that covers that core. At the tip portion of the bristle, the core protrudes further than the sheath and acts as an electrode.