@article{oai:niigata-u.repo.nii.ac.jp:00003652,
 author = {吉田, 教明 and 古賀, 義之 and Paul-Georg, Jost-Brinkmann and 阿部, 里砂子 and 小林, 和英 and 山田, 好秋},
 issue = {1},
 journal = {日本顎口腔機能学会雑誌, 日本顎口腔機能学会雑誌},
 month = {Sep},
 note = {The type of tooth movement is described simply by the center of rotation. Therefore, orthodontic tooth movements can be predicted, when each location of the center of rotation under various force systems is clarified. The purpose of this study was to develop a magnetic sensing system for three dimensional displacement and to determine the location of center of rotation of the maxillary central incisor. Lingually directed forces were applied at different horizontal levels in human subjects. The main part of the system is composed of eight hall elements and a samarium cobalt magnet. The relationship between the location of center of rotation and theposition of the force application was discussed. It was concluded as follows ; 1. Rresolutioh was determined to be less than 1μm and distortion of the system was calculated at less than 0.7% within the range of ±300μm. This system was estimated to be stable and sensitive enough to be applied in the oral cavity and to measure the tooth movements in vivo. 2. when a lingually directed force was applied at the bracket position of the tooth, the center of rotation was observed at a point 0.44 times the root length from the alveolar crest. This indicated that the tooth crown tended to move lingually and the root tended to move labially, or oppositely when only a single force was applied to maxillary incisors during the anterior teeth retraction. 3. When the point of force application was moved cervically, the center of rotation also moved toward the same direction. It was shown that the center of rotation is located at the root apex when the force was applied at a point 5 mm cervical from the bracket position. 4. As the location of force application moved further apically, the direction of rotation changed from crown-lingual to root-lingual at a point between 6 and 8 mm cervical from the bracket position. This study was supported by DFG Grant Mi198/4-1., 荷重時の歯の移動様式は回転運動として，中心点，半径，角度で表現することができる．したがって，特定の力系に対する歯の回転中心を求めることは，歯の移動様式を予測することと等価である．本研究では，新たに開発した磁気センサを応用した3次元変位測定システムを用いて，矯正力作用時の上顎中切歯の変位量を実測し，荷重位置と回転中心の関係について検討した．被験者は27歳の成人女性1名で，被験歯は上顎左側中切歯とした．被験歯に負荷する荷重量は150gとした．得られた結論を以下に述べる．　1．ホール素子と磁石を組み合わせることで，歯の微小変位を非接触で3次元的に測定できるシステムを開発し，口腔内への応用を試みた．変位測定システムの基本性能を検討したところ，1μm以内の分解能をもち，測定誤差は±300μmの範囲で0.7%以下であった．以上より，本システムは歯の微小変位を定量的に測定するための十分な特性を有することが確認できた．　2．舌側方向の矯正力を上顎中切歯のブラケット位置に負荷した時に，回転中心は歯槽頂より歯根長の44%根尖側寄りの位置に観察された．上顎前歯の舌側牽引時に単力のみを負荷すると，歯冠は舌側へ移動するものの，歯根が荷重方向と反対の唇側へ移動する傾向が示された．　3．荷重位置を歯頚側方向へ移動すると，回転中心は根尖に向かって移動した．ブラケットから5mmほど歯頚側寄りの位置に荷重を負荷すると，回転中心は根尖に観察された．　4．荷重位置をさらに根尖方向へ移動すると，ブラケットから歯頚側寄りに6mmから8mmの間で，回転方向が逆転し，歯冠舌側傾斜から歯根舌側傾斜へ変化した．},
 pages = {21--30},
 title = {荷重時の歯の回転中心に関する研究 : 磁気センサを応用した3次元変位測定システムの生体への応用},
 volume = {5},
 year = {1998}
}