MMP-9在去势大鼠正畸牙齿压力侧牙槽骨表达的研究

摘要

AIM:To observe the effects of orthodontic movements on alveolar bone resorption in ovariectomized rats.METHODS:Fifty 6-month old female Wistar rats were randomly divided into ovariectomized group (n =25) and control group(n =25).Osteoporosis model was established by six months after spaying.Orthodontic appliance was placed between the maxillary first molar and maxillary central incisors.MMP-9 expression and osteoclast number were examined with immunohistochemical technique and tartrate resistant acid phosphatase (TRAP) staining 0,5,7,10 and 14 days after tooth movement respectively.RESULTS:0 ～ 10 d after orthodontic appliance application in ovariectomized group MMP-9 expression was stronger and osteoclasts were more than those in the control group (P ＜ 0.05).14 days after orthodontic treatment the osteoclast number was not significantly different between the two groups (P ＞ 0.05),but MMP-9 expression was stronger in ovariectomized group than in the control group (P ＜ 0.05).CONCLUSION:Osteoporosis may increase alveolar bone resorption during orthodontic treatment.%目的:比较不同正畸加力时间牙槽骨压力侧破骨细胞数和MMP-9表达水平,探讨骨质疏松对正畸力作用下骨代谢的影响.方法:取6月龄雌性Wistar大鼠50只,随机分为去势组和对照组(每组25只).去势组大鼠切除双侧卵巢建立骨质疏松模型.术后6个月,于两组大鼠上颌双侧磨牙与中切牙之间安装矫治器,并施以0.49 N的拉力.分别于加力后0、5、7、10、14 d取材,免疫组化及抗酒石酸酸性磷酸酶(TRAP)染色法检测各组大鼠上颌第一磨牙压力侧牙周组织中MMP-9表达水平及破骨细胞数.结果:去势组和对照组大鼠移动牙齿压力侧MMP-9表达水平及破骨细胞数均随加力时间延长而增加,加力7d时达到高峰,10d后逐渐降低;相同加力时间点内两组相比,去势组MMP-9的表达和破骨细胞数均高于对照组,除加力14 d时两组破骨胞数无统计学差异(P＞0.05)外,其他差异均有统计学意义(P＜0.05).结论:骨质疏松状态下大鼠正畸移动牙齿压力侧牙槽骨吸收活动增强.