Orthodontics Department, School of Dentistry University of Genova largo Rosanna Benzi, 10 16132, Genoa, Italy.
Department of Orthodontics and Pediatric Dentistry, University of Michigan, School of Dentistry, Ann Arbor, USA.
Head Face Med. 2021 Jan 15;17(1):1. doi: 10.1186/s13005-020-00252-0.
The aim of the present study was to compare two different anchorage systems efficiency to disinclude impacted maxillary canines using as evaluation tool superimposed Cone Beam Computed Tomography (CBCTs).
The study has been conducted with two parallel groups with an allocation ratio of 1:1. Group test received treatment using as anchorage a miniscrew, control group was treated using an anchorage unit a trans palatal arch (TPA). Both groups received a calibrated traction force of 50 g. CBCT before treatment and 3 months after traction were superimposed and canine tip and root movement were evaluated in mm/month ratio.
No differences were observed between groups for apex displacement, tip displacement and observation timespan. Twenty-two patients (12 female, 10 male, mean age:13.4 years) undergoing orthodontic treatment for impacted maxillary canines were recruited for this study. No differences were observed between groups for apex displacement, tip displacement and observation timespan.
The present pilot study provided no evidence that indirect anchorage on miniscrews could make canine disimpaction faster than anchorage on a TPA. An apex root movement of 0.4-0.8 mm per month was found, while average canine tip movement ranged between 1.08 mm and 1.96 mm per month. No miniscrews failures were observed.
The study reports the preliminary results of the randomized clinical trial registered at www.register.clinicaltrials.gov (registration number: NCT01717417 ).
本研究旨在比较两种不同的支抗系统在使用叠加锥形束 CT（CBCT）作为评估工具的情况下，排除上颌埋伏尖牙的效率。
本研究采用平行分组，分配比例为 1:1。实验组使用迷你螺钉作为支抗，对照组使用横腭杆（TPA）作为支抗。两组均施加 50g 的校准牵引力。在治疗前和牵引后 3 个月对 CBCT 进行叠加，并以 mm/月的比值评估尖牙尖端和根的移动。
两组在根尖位移、尖端位移和观察时间方面均无差异。本研究共纳入 22 名（12 名女性，10 名男性，平均年龄 13.4 岁）接受正畸治疗的上颌埋伏尖牙患者。两组在根尖位移、尖端位移和观察时间方面均无差异。
本初步研究未提供证据表明迷你螺钉的间接支抗可以使尖牙的排齐速度快于 TPA 的支抗。发现根尖-根移动每月为 0.4-0.8mm，而平均尖牙尖端移动每月在 1.08mm 和 1.96mm 之间。未观察到迷你螺钉失败。
本研究报告了在 www.register.clinicaltrials.gov（注册号：NCT01717417）注册的随机临床试验的初步结果。
