矫治力初期牙髓组织HSP70表达及临床意义

The expression of HSP70 in dental pulp tissues in early orthodntic force and its clinical significance

目的观察在矫治力初期牙髓组织中heat shock protein 70(HSP70)的分布及表达,探讨适宜的矫治力对牙髓组织的影响并正确运用生物力学原则。方法 16例采用拔除上颌双侧第一前磨牙进行固定矫治的患者,随机分为正常对照组,加力(0.5 N)1、3、7 d组在受力相应时段拔除,并制备石蜡标本。免疫组织化学法(SABC)观察牙髓中HSP70的表达及分布。结果HSP70的阳性反应产物呈深褐色均质性沉淀,主要在血管内皮细胞,成牙本质细胞胞质周围呈颗粒状阳性表达。在加力1 d组HSP70的表达并没有明显增强(P>0.05),3天组表达达高峰尤其是在血管内皮细胞中(P<0.01),到7天后牙髓细胞的整体表达呈弱阳性。所有病例无一例牙髓坏死。结论在牙移动过程中牙髓组织中HSP70的表达先升高后又逐渐减低至恢复正常水平,提示HSP70在牙移动过程中对牙髓组织的改建过程可能起着重要作用;适宜的矫治力作用下产生的HSP70可能对牙髓组织提供了有效的保护。

Objective To detect the expression and distribution of HSP70 in human dental pulp tissues and to analyze the influences of orthodontic forces on dental pulp and to use biomechanic principle correctly. Methods 16 patients were randomly assigned to control group and 1d,3d and 7d groups after orthodontics. The test teeth were extracted at the corresponding time and paraffin was prepared. Immunohistochemical method（SABC method） was utilized to localize and examine the expression of HSP70. Results HSP70 was stained inodontoblast,vascular enelothelial cells and some smooth muscle cells. The expression of HSP70 didn＇tincreaseobviously in1 d group（P 〉0. 05）; it reached the highest level in 3d group especially in smooth muscle cell of vessel wall（P 〈0. 01） and decreased greatly in 7d group. There was no pulp necrosisin all cases. Conclusions The changes of HSP70 in dental pulp during orthodontic tooth movement suggest that nitricoxide may play an important role in pulp self-repair. HSP70 may provide effective protection to pulp tissue with appropriate force.