The aim was to investigate the effect of mechanical vibration on root resorption with or without orthodontic force application. Twenty patients who required maxillary premolar extractions as part of orthodontic treatment were randomly divided into two groups of 10: no-force group and force group. Using a split-mouth procedure, each patient’s maxillary first premolar teeth were randomly assigned as either vibration or control side for both groups. A buccally directed vibration of 50 Hz, with an Oral-B HummingBird device, was applied to the maxillary first premolar for 10 min/day for 12 weeks. After the force application period, the maxillary first premolars were extracted and scanned with micro-computed tomography. Fiji (ImageJ), performing slice-by-slice quantitative volumetric measurements, was used for resorption crater calculation. Total crater volumes were compared with the Wilcoxon and Mann–Whitney U tests. The total crater volumes in the force and no-force groups were 0.476 mm3 and 0.017 mm3 on the vibration side and 0.462 mm3 and 0.031 mm3 on the control side, respectively. There was no statistical difference between the vibration and control sides (P > 0.05). There was more resorption by volume in the force group when compared to the no-force group (P < 0.05). Mechanical vibration did not have a beneficial effect on reducing root resorption; however, force application caused significant root resorption.

中文翻译：

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12 周机械振动对牙根吸收的影响：显微 CT 研究


目的是研究机械振动对有或没有正畸力施加的牙根吸收的影响。将 20 名需要拔除上颌前磨牙作为正畸治疗一部分的患者随机分为两组，每组 10 人：无力组和力组。使用分口手术，将每位患者的上颌第一前磨牙随机分配为两组的振动侧或控制侧。使用 Oral-B HummingBird 装置对上颌第一前磨牙施加 50 Hz 的颊向振动，每天 10 分钟，持续 12 周。施力期结束后，拔除上颌第一前磨牙并使用微型计算机断层扫描进行扫描。 Fiji (ImageJ) 进行逐层定量体积测量，用于计算吸收坑。将弹坑总体积与 Wilcoxon 和 Mann-Whitney U 测试进行比较。受力组和无力组的总凹坑体积在振动侧分别为 0.476 mm3 和 0.017 mm3，在控制侧分别为 0.462 mm3 和 0.031 mm3。振动侧与控制侧差异无统计学意义（P>0.05）。与无力组相比，有力组的体积吸收更多（P < 0.05）。机械振动对减少牙根吸收没有有益作用；然而，施加力会导致显着的牙根吸收。