Alternative Title前歯のen-mass牽引時に最適な矯正力とM/Fを生じるシンプルで新しいクロージングループデザイン
Degree grantor/typeNagasaki University (長崎大学)
Note (General)Purpose: The aim of this study was to clarify the mechanical conditions of loop activation that produce the optimal force system allowing controlled movement of the anterior teeth. Materials and Methods: The closing loop examined in this study was a 10-mm-high teardrop type bent from a 0.017 × 0.025-inch stainless steel archwire. A loop design that can generate a high moment-to-force (M/F) ratio and the optimal force magnitude was investigated by varying the rate of the cross-sectional reduction of the loop apex, the amount of loop activation and the degree of gable bend. Forces and moments acting on closing loops were calculated using structural analysis based on the tangent stiffness method. Results: A force magnitude of 302 g and an M/F ratio higher than 10 (sufficiently high to achieve bodily movement of the anterior teeth) could be produced when the thickness of the cross-section of a 10-mm-high teardrop loop was reduced by half for a distance of 3 mm from the apex and a gable bend of 30° was incorporated into the loop. Conclusions: The optimal force magnitude and M/F ratio for achieving controlled tipping or bodily movement of the anterior teeth can be produced by partially reducing the thickness of the teardrop loop, and by placing a gable bend of 20° to 30° in the 0.018-inch bracket slot system.
長崎大学学位論文 学位記番号:博(医歯薬)甲第1276号 学位授与年月日:令和2年9月2日
Author: Satoshi Yamaoka, Ryo Hamanaka, Tuan anh Nguyen, Sachio Jinnai, Jun-ya Tominaga, Yoshiyuki Koga, Noriaki Yoshida
Citation: Orthodontic Waves, 79(2-3), pp.77-82; 2020
identifier:Nagasaki University (長崎大学), 博士(歯学) (2020-09-02)
http://hdl.handle.net/10069/40347
DOIinfo:doi/10.1080/13440241.2020.1770558
Collection (particular)国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文
Date Accepted (W3CDTF)2021-06-07T02:06:26+09:00
Data Provider (Database)国立国会図書館 : 国立国会図書館デジタルコレクション