Department of Orthodontics, School of Dentistry, National & Kapodistrian University of Athens, Athens, Greece.
School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio, USA.
J Musculoskelet Neuronal Interact. 2022 Jun 1;22(2):235-241.
The aim of this study was to investigate the effect of the application of orthodontic tooth forces on the alveolar bone distal to the loaded teeth, in ovariectomized female rats.
Twenty-four eight-month-old Wistar rats were divided into one group ovariectomized at the age of six months and one control. An orthodontic appliance delivering a mesial traction force of 60 gr* was placed on the right maxillary 1 molar of all animals for 14 days. Histology of the alveolar bone, of the adjacent and distal teeth to the loaded molar and the contralateral side, was performed following euthanasia.
In the non-ovariectomized rats, extensive resorption was noticed in the direction of the orthodontic movement in the 2 and 3 molar interdental space, whereas the respective contralateral interdental space did not show any remodeling activity. Ovariectomized rats displayed reduced osseous tissue in the interdental space of both sides. The alveolar bone in the interradicular area of the 2 loaded molar revealed frontal resorption, whereas, the alveolar interradicular bone of the contralateral 2 molar showed internal resorption.
In conclusion, orthodontic forces applied to the dentoalveolar complex of ovariectomized rats affect bone remodeling, even in areas distal to the site of force application. This finding should be taken into account during orthodontic treatment of women during menopause.
本研究旨在探讨正畸力对去负荷牙齿远中牙槽骨的影响。
将 24 只 8 月龄 Wistar 大鼠随机分为去势组和对照组。所有动物的右侧上颌第一磨牙均施加 60 克的近中牵引力 14 天。处死动物后进行牙槽骨组织学检查，包括去负荷磨牙及其相邻和远中牙齿以及对侧牙齿。
在未去势的大鼠中，在正畸移动的方向上观察到 2 和 3 磨牙之间的广泛吸收，而相应的对侧牙间隙没有任何改建活动。去势大鼠双侧牙间隙的骨组织减少。2 个加载磨牙的根间区牙槽骨呈现前吸收，而对侧 2 磨牙的牙槽骨间内吸收。
总之，正畸力施加于去势大鼠的牙牙槽复合体，会影响骨改建，即使在力作用部位的远中区域也是如此。在绝经期妇女的正畸治疗中应考虑到这一发现。
