To straighten bristle tips without bending them outside or sideways in order to recover toothbrushing effect of a toothbrush whose bristle tips are bent and spread by use.

A clip 1 has many fine straight projections or grooves on both inner surfaces of a gripping part 2 along a direction for gripping. The clip 1 grips, from both sides, a root part 7 of a bristle planting part 6 in a length direction of a handle from the back of an implanting base 8 of the toothbrush 4. The gripping part 2 of the clip 1 slides from a root part 7 of bristles 6 that are fixed to the bristle implanting base 8 toward the soft bristle tips 9 by a closing force of the clip 1. The bristle tips 9 are guided straight by the straight projections or grooves that are formed on the inner surfaces of the gripping part 2. The back of the bristle implanting base 8 is butted against an innermost wall 10 inside the clip 1 and stopped so as to grip bristle tips 9 straight and to keep this state. Thereby, it is possible to correct the bristle tips straight by preventing them from bending outside and sideways, i.e. the length direction of the handle.