Provided is a treatment tool that facilitates the operation of cutting a root canal of a tooth or removing a nerve thereof, thereby reducing fatigue of a dentist to allow the dentist to maintain his/her concentration. A vibration-side housing (14) is attached to a tip of a handle-side housing (10), and a motor (2) in which a plate cam (21) is attached to a rotating shaft (20) is housed. A vibration tube mounting opening (15) opens at distal end part of the vibration-side housing (14), and a vibration tube (16) is mounted thereon. The vibration tube (16) is provided to vibrate in a forward-backward direction while urged in the plate cam (21) direction via a spring (18) with respect to the vibration-side housing (14). The vibration tube (16) contacts with the plate cam (21) via a roller (19) at a rear end part. A reamer mounting opening (17) opens at a tip of the vibration tube (16), and receives and tightly holds an insertion part (30) of the reamer (3). The reamer (3) including the bendable needle part (31) is attachable/detachable to the vibration-side housing (12).
