应用微种植支抗大鼠牙齿移动过程中牙周组织OPN的表达变化

Change of OPN expression and distribution during orthodontic tooth movement with application of implant anchorage in rats

目的观察应用微型种植支抗使大鼠牙齿移动过程中骨桥蛋白(OPN)的表达变化,探讨其在成骨细胞诱导和骨改建中的作用。方法建立应用微型种植支抗牵引移动大鼠下颌第一磨牙的实验模型。OTM组在大鼠右侧下颌做加力牵引,左侧下颌作为对照组,分别于OTM后2、4、7及14天,解剖分离大鼠下颌骨,HE染色观察组织形态,免疫组织化学检测OPN表达变化及时间分布特点。结果 HE显示OTM组中张力侧成骨细胞、压力侧破骨细胞表达较多。免疫组化显示OTM组OPN阳性细胞数随加力时间的增加而增加,第7天达到高峰,此后逐渐降低。结论在正畸牙移动过程中,OPN表达的变化规律与骨改建过程中成骨细胞分化、形成和功能密切相关,与牙槽骨改建过程一致。

Objective The aim of this study was to investigate the osteopontin （OPN） expression in the periodontal tissues and to understand its possible roles in alveolar bone remodeling through orthodontic tooth movement （OTM） with application of implant anchorage in rats. Methods Orthodontic force with application of implant anchorage was used to move mesially the right mandibular molars of the rats. And the left mandibular was the control. The rats were sacrificed after 2d-4d, 7d and 14 d respectively. This procedure was assessed by haematoxylin and eosin was performed to assess the general morphologic change of the mandible and immunohistochemical detection was performed for detection of osteopontin （OPN）. Results Osteoblasts increased in number on the tension side of the periodontal ligament space whereas osteoclast increased in number in the compression side. Immunohistochemistry shows that OPN was detectable in the tension region during OTM, but absent in the control group. The expression intensity increased over time and peaked at 7d of OTM. Conclusion The changing tendency of OPN was consistent with the change of bone remodeling and the number of positive osteoblasts. OPN may play an important role in the bone remodeling during orthodontic tooth movement.