Department of Dentistry, section of Orthodontics and Craniofacial Biology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
3D Lab, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
Clin Oral Investig. 2021 Apr;25(4):1945-1952. doi: 10.1007/s00784-020-03502-2. Epub 2020 Aug 18.
Individual orthodontic treatment duration is hard to predict. Individual biological factors are amongst factors influencing individual rate of orthodontically induced tooth movement (OTM). The study aim is to determine the rate of OTM by a novel 3D method and investigate parameters that may predict the rate of tooth movement.
In this prospective cohort study, rate of OTM was determined from 90 three-dimensional intra-oral scans in 15 patients (aged 12-15) undergoing orthodontic treatment. For each patient, intra-oral scans were taken every week for up to 6 weeks (T0-T5). The teeth were segmented from the scans and the scans were superimposed on the palatal rugae. The rate of OTM was calculated for each tooth. Other parameters were gingival inflammation, contact-point displacement and the biological markers, matrix metalloproteinases (MMP), MMP-9 and MMP-2 in gingival crevicular fluid (GCF).
Our study showed a high variation in the rate of OTM, varying from 0.15 to 1.24 mm/week. Teeth in the anterior segment tended to move more compared with the posterior segment. The contact point displacement and gingival inflammation varied greatly amongst the patients. The MMPs measured did not correlate with tooth movement. However, the gingival inflammation index showed a significant correlation with OTM. Future studies should include other biological markers related to bone-remodeling.
This novel and efficient 3D method is suitable for measuring OTM and showed large individual variation in rate of OTM.
Patients show different rates of OTM. The rate of OTM in an individual patient can provide guidance in timing of follow-up appointments.
个体正畸治疗时间难以预测。个体生物学因素是影响正畸牙齿移动（OTM）个体速度的因素之一。本研究旨在通过一种新的 3D 方法确定 OTM 速度，并研究可能预测牙齿移动速度的参数。
在这项前瞻性队列研究中，从 15 名（12-15 岁）接受正畸治疗的患者的 90 个三维口腔内扫描中确定 OTM 速度。对于每个患者，在最多 6 周（T0-T5）的时间内每周进行一次口腔内扫描。从扫描中分割牙齿，并将扫描与腭皱襞叠加。计算每颗牙齿的 OTM 速度。其他参数为牙龈炎症、接触点位移以及牙龈沟液（GCF）中的基质金属蛋白酶（MMP）、MMP-9 和 MMP-2 等生物标志物。
我们的研究表明，OTM 速度的变化很大，从 0.15 到 1.24 毫米/周不等。前牙段的牙齿移动速度比后牙段快。患者之间的接触点位移和牙龈炎症差异很大。测量的 MMP 与牙齿移动无关。然而，牙龈炎症指数与 OTM 呈显著相关性。未来的研究应包括与骨重塑相关的其他生物标志物。
这种新颖有效的 3D 方法适用于测量 OTM，并且显示出很大的个体间 OTM 速度差异。
患者表现出不同的 OTM 速度。个体患者的 OTM 速度可以为随访预约时间提供指导。
