The present invention provides a treatment tool capable of surely treating wound of ingrown nail also near a root of a nail in addition to near a tip of the nail and immediately relieving pain of the wound of the ingrown nail. An adhesive plaster structure 1 attached to a finger/toe along a lateral nail edge, the adhesive plaster structure 1 comprising: a wound adhesion area 2 having a flexible wound adhesion surface 2A； and a guide area 3 having a slide groove 3A that receives the lateral nail edge, the slide groove being capable of sliding in a longitudinal direction of a nail along the lateral nail edge, wherein the slide groove 3A extends at least over a part of a length between the tip portion and the rear end portion of the adhesive plaster structure 1 in the longitudinal direction of the adhesive plaster structure 1, and the flexible wound adhesion surface is guided to a position of the wound caused by the ingrown nail when the adhesive plaster structure 1 is attached to the finger/toe.
