Discipline of Orthodontics, School of Dentistry, Faculty of Medicine and Health, University of Sydney; Department of Orthodontics, Sydney Dental Hospital, Sydney Local Health District, Sydney, New South Wales, Australia.
Australian Centre for Microscopy and Microanalysis, University of Sydney, Sydney, New South Wales, Australia.
Am J Orthod Dentofacial Orthop. 2018 Sep;154(3):326-336. doi: 10.1016/j.ajodo.2018.04.022.
The purpose of this 2-arm-parallel split-mouth trial was to investigate the effect of low-level laser therapy (LLLT) on the repair of orthodontically induced inflammatory root resorption (OIIRR).
Twenty patients were included in this study, with 1 side randomly assigned to receive LLLT, and the other side served as a sham. Eligibility criteria included need for bilateral maxillary first premolar extractions as part of fixed appliance treatment. OIIRR was generated by applying 150 g of buccal tipping force on the maxillary first premolars for 4 weeks. After the active force was removed, the teeth were retained for 6 weeks. LLLT commenced with weekly laser applications using a continuous beam 660-nm, 75-mW aluminum-gallium-indium-phosphorus laser with 1/e spot size of 0.260 cm, power density of 0.245 W/cm, and fluence of 3.6 J/cm. Contact application was used at 8 points buccally and palatally above the mucosa over each tooth root for 15 seconds with a total treatment time of 2 minutes. After 6 weeks, the maxillary first premolars were extracted and scanned with microcomputed tomography for primary outcome OIIRR calculations. Subgroup analysis included assessment per root surface, per vertical third, and sites of heaviest compressive forces (buccal-cervical and palato-apical). Randomization was generated using www.randomization.com, and allocation was concealed in sequentially numbered, opaque, sealed envelopes. Blinding was used for treatment and outcome assessments. Two-tailed paired t tests were used to determine whether there were any statistically significant differences in total crater volumes of the laser vs the sham treated teeth.
Total crater volumes were 0.746 mm for the laser treated teeth and 0.779 mm for the sham. There was a mean difference of 0.033 ± 0.39 mm (95% CI, -0.21 to 0.148 mm) greater resorption crater volume in the sham group compared with the laser group; this was not statistically significant (P = 0.705). No harm was observed.
No significant difference was found between LLLT and sham control groups in OIIRR repair.
本研究采用 2 臂平行分口试验，旨在探讨低水平激光疗法（LLLT）对正畸诱导的炎症性根吸收（OIIRR）修复的影响。
本研究纳入了 20 名患者，每侧随机接受 LLLT 或假照射治疗。入选标准包括需要双侧上颌第一前磨牙作为固定矫治器治疗的一部分进行拔牙。通过在上颌第一前磨牙施加 150g 的颊向倾斜力 4 周来产生 OIIRR。去除主动力后，牙齿保留 6 周。LLLT 从每周一次的激光治疗开始，使用连续光束 660nm、75mW 铝镓铟磷激光，光斑尺寸为 1/e 的 0.260cm，功率密度为 0.245W/cm，剂量为 3.6J/cm。接触应用于每颗牙根上方和下方的黏膜颊侧和腭侧 8 点，每次 15 秒，总治疗时间为 2 分钟。6 周后，上颌第一前磨牙被拔除，并使用微计算机断层扫描进行主要结果 OIIRR 计算。亚组分析包括每根表面、每垂直三分之一和最重压缩力（颊侧-颈侧和腭侧-根尖侧）部位的评估。使用 www.randomization.com 生成随机分组，使用顺序编号、不透明、密封的信封隐藏分组。采用双尾配对 t 检验确定激光治疗组和假照射治疗组的总侵蚀坑体积是否存在统计学显著差异。
激光治疗组的总侵蚀坑体积为 0.746mm，假照射治疗组为 0.779mm。与激光组相比，假照射组的侵蚀坑体积平均增加 0.033±0.39mm（95%CI，-0.21 至 0.148mm），差异无统计学意义（P=0.705）。未观察到不良事件。
LLLT 组和假照射对照组在 OIIRR 修复方面无显著差异。
