An elongated treatment tool having a treatment portion disposed on a longitudinal axis thereof. The treatment portion includes a first treatment surface having a first electrode and a first insulative surface formed therein. The first electrode is disposed at a center in direction perpendicular to the longitudinal axis. The first insulative surface is disposed outwardly with respect to the first electrode. A second treatment surface having a second insulative surface and a second electrode formed therein. The second treatment surface is oriented in facing relationship with respect to the first treatment surface. When the first and second treatment surfaces are held in abutment against one another, the first insulative surface abuts against the second electrode and the second insulative surface and the second insulative surface abuts against the first electrode and the first insulative surface, thereby preventing a short circuit between the first electrode and the second electrode.
