Eslamian Ladan, Ebadifar Aliasghar, Mohebbi Rad Masoud, Motamedian Saeed Reza, Badiee Mohammad Reza, Mohammad Rahimi Hossein, Farahani Mohammad Hosein
Dental Research Center, Research Institute of Dental Sciences, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Dentofacial Deformities Research Center, Research Institute of Dental Sciences, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
J Lasers Med Sci. 2020 Fall;11(Suppl 1):S37-S42. doi: 10.34172/jlms.2020.S6. Epub 2020 Dec 30.
This study was performed to compare the effects of single and multiple irradiations of low-level laser therapy (LLLT) on bone regeneration in a mid-palatal suture following rapid palatal expansion (RPE). In this animal study, 40 male Wistar rats underwent RPE for 7 days and were divided into 4 groups including A: single LLLT on day 7, B: Multiple LLLT on days 7, 9, 11, 13 and 15, C: control (no LLLT), and D: sacrificed on day 7. Animals in group D were used to determine the amount of suture expansion. LLLT was done by a diode laser set at an 808 nm wavelength with a useful power output of 100 mW and duration of 0.1 ms. LLLT was applied to three points. After three weeks of retention, the rats were sacrificed and beheaded and the maxilla was evaluated by occlusal radiography, µ-CT, and histomorphometric analyses. A comparison of the mean measurements between the groups was performed using ANOVA and the Tukey post hoc test. Based on occlusal radiography and µCT, bone density in group B was significantly higher than group A and group C (<0.05). There was no significant difference in bone density between group A and group C (>0.05). Mean suture width (MSW) in group B was significantly lesser than the control group (=0.027) while there was no significant difference between MSWnin groups A and B (=0.116) and groups A and C (=0.317). It may be concluded that multiple low-power laser irradiation improves bone regeneration after RPE while single irradiation does not have a positive effect.
本研究旨在比较低强度激光疗法（LLLT）单次和多次照射对快速扩弓（RPE）后腭中缝骨再生的影响。在这项动物研究中，40只雄性Wistar大鼠接受了7天的RPE，并分为4组，包括A组：第7天单次LLLT；B组：第7、9、11、13和15天多次LLLT；C组：对照组（无LLLT）；D组：第7天处死。D组动物用于确定缝扩张量。LLLT由一台二极管激光器完成，设置波长为808nm，有效功率输出为100mW，持续时间为0.1ms。LLLT应用于三个点。保留三周后，处死大鼠并斩首，通过咬合片、显微CT和组织形态计量分析对上颌骨进行评估。使用方差分析和Tukey事后检验对各组间的平均测量值进行比较。基于咬合片和显微CT，B组的骨密度显著高于A组和C组（<0.05）。A组和C组之间的骨密度无显著差异（>0.05）。B组的平均缝宽（MSW）显著小于对照组（=0.027），而A组与B组（=0.116）以及A组与C组（=0.317）之间的MSW无显著差异。可以得出结论，多次低功率激光照射可改善RPE后的骨再生，而单次照射没有积极作用。
