PROBLEM TO BE SOLVED: To provide an inexpensive electric toothbrush having high cleaning properties for gingival crevices in drum-shaped cavities in a tooth adjacent interdental part, by setting in a biologically appropriate range, a vibration frequency of vibration pressure stimulus which the brush applies to the periodontal tissue, and increasing a massage action on the periodontal tissue.SOLUTION: An electric toothbrush includes means which limits a frequency at which a brush hair bundle intermittently and repeatedly contacts a specific portion of the periodontal tissue to 700 times or less per minute, by electrically limiting a rotational frequency of a motor so as to limit a velocity at which the brush repeatedly draws a specific motion track.SELECTED DRAWING: Figure 3COPYRIGHT: (C)2017,JPO&INPIT【課題】ブラシが歯周組織に及ぼす振動的圧力刺激の振動数を生物学的に妥当な範囲に設定して、歯周組織に対するマッサージ作用を高め、歯牙隣接歯間部鼓形空隙にある歯肉溝への高い清掃性を有する、安価な電動歯ブラシを提供する。【解決手段】モーターの回転数を電気的に制御することによって、ブラシが特定の運動軌跡を繰り返して描く速さを制限して、ブラシ毛束が歯周組織の特定の箇所に断続的に繰り返して接する頻度を、1分間当たり700回以下に制限することを手段とする。【選択図】図3
