To clean teeth without damaging an organism and to easily infiltrate various chemicals into an interdental/periodontal tissue by arranging a feeding means feeding various chemicals to the dental/periodontal tissue and a sucking means sucking the material retained on the tissue.

A chemical is filled in a tubular feeding means 3, fine holes are provided on the tubular feeding means 3, and the chemical is discharged and fed to the outside from the holes. An outer skin 1 is a cord-like object connected to an external chemical feeding means 3. The feeding means 3 is inserted to a tooth 4, then it is squeezed by a feeding means position adjusting means 2 at a place where the chemical is to be fed. The chemical reaches the feeding means 3 from a chemical feeding means body through a tube passing in the outer skin 1 and is discharged and fed to a periodontal pocket. A syringe may be used as a driving means for sucking.