Seifi Massoud, Kazemi Bahram, Kabiri Sattar, Badiee Mohammadreza
Marquette University School of Dentistry, Milwaukee, Wisconsin, USA.
Cellular and Molecular Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Cell J. 2017 Jul-Sep;19(2):278-282. doi: 10.22074/cellj.2016.4218. Epub 2017 Feb 22.
Root resorption is a complication of orthodontic treatment and till date, there is a dearth of information regarding this issue. The aim of this study was to determine whether the expression of transforming growth factor-β1 (TGF-β1, an inflammatory cytokine) is related to orthodontic force. Moreover, if associated, the expression level may be helpful in differential diagnosis, control and ultimate treatment of the disease.
In this experimental study, a total of 24 eight-week-old male Wistar rats were selected randomly. On day 0, an orthodontic appliance, which consisted of a closed coil spring, was ligated to the upper right first molar and incisor. The upper left first molar in these animals was not placed under orthodontic force, thus serving as the control group. On day 21, after anesthesia, the animals were sacrificed. The rats were then divided into two equal groups where the first group was subjected to histological evaluation and the second group to reverse transcriptase-polymerase chain reaction (RT-PCR). Orthodontic tooth movement was measured in both groups to determine the influence of the applied force.
Statistical analysis of data showed a significant root resorption between the experimental group and control group (P<0.05), however, there was no significant difference in the expression level of the inflammatory cytokine, .
Based on the findings of this study, we suggest that there is a direct relationship between orthodontic force and orthodontic induced inflammatory root resorption. In addition, no relationship is likely to exist between root resorption and expression in the resorptive lacunae.
牙根吸收是正畸治疗的一种并发症，迄今为止，关于这个问题的信息匮乏。本研究的目的是确定转化生长因子-β1（TGF-β1，一种炎性细胞因子）的表达是否与正畸力有关。此外，如果有关联，其表达水平可能有助于该疾病的鉴别诊断、控制及最终治疗。
在本实验研究中，随机选取24只8周龄雄性Wistar大鼠。在第0天，将由闭合螺旋弹簧组成的正畸矫治器结扎于右上第一磨牙和切牙。这些动物的左上第一磨牙未施加正畸力，作为对照组。在第21天，麻醉后处死动物。然后将大鼠分为两组，每组数量相等，第一组进行组织学评估，第二组进行逆转录聚合酶链反应（RT-PCR）。测量两组的正畸牙移动情况以确定所施加力的影响。
数据的统计分析显示实验组与对照组之间存在显著的牙根吸收（P<0.05），然而，炎性细胞因子的表达水平无显著差异。
基于本研究结果，我们认为正畸力与正畸诱导的炎性牙根吸收之间存在直接关系。此外，牙根吸收与吸收陷窝中的表达之间可能不存在关联。
