The Role of Power Arm by Combined Use of Clear Aligner and Miniscrew in En-Masse Retraction of Maxillary Anterior Teeth
10.16156/j.1004-7220.2021.01.13
- VernacularTitle:Power Arm在隐形矫治器联合微种植钉整体内收上前牙中的作用
- Author:
Yu BAI
1
;
Hejian ZHAO
1
;
Fugang YANG
2
;
Meng CAO
1
Author Information
1. State Key Laboratory of Military Stomatology ＆ National Clinical Research Center for Oral Diseases ＆ Shanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, the Fourth Military Medical University
2. Department of Ophthalmology and Otorhinolaryngology, the Hospital of Chinese People’s Liberation Army 61150
- Publication Type:Journal Article
- Keywords:
clear aligner (CA);
micro-implant anchorage (MIA);
en-mass retraction
- From:
Journal of Medical Biomechanics
2021;36(1):E079-E084
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the role of Power Arm in en-masse retraction of maxillary anterior teeth using clear aligner (CA) and micro-implant anchorage (MIA). Methods The three-dimensional (3D) model of maxillary anterior teeth by combined use of CA and MIA was established, and the 6 mm-height Power Arm, was attached to the canine or appliance. The initial displacement and the maximum von Mises stress of periodontal ligament under three loading conditions were analyzed, namely the force was loaded by CA+150 g retraction force at canine, CA+150 g retraction force on Power Arm at appliance, CA+150 g retraction force on Power Arm at canine. Results In sagittal direction, the crown and root displacement difference of maxillary central incisor was 129, 129, 133 μm，respectively. The crown displacement of the maxillary first molar was -23.3, -23.5, -26.8 μm, respectively. The maximum von Mises stress of periodontal ligament in central incisor was 48.4, 72.6, 40.0 kPa, respectively, and that of the first molar was 5.3, 10.5, 5.8 kPa, respectively. Conclusions It can not be testified that retraction of the 6 mm-height Power Arm at canine or appliance with 5 mm-height mini-screw has more advantages than retraction of the canine directly for more favorably controlling the torque of incisors, saving anchorage of posterior teeth and decreasing von Mises stress of the periodontal ligament.
