单侧咬合创伤建立大鼠颞下颌关节骨关节炎模型的组织病理学观察

Histopathological evaluation of temporomandibular joint osteoarthritis in rats induced by unilateral occlusal trauma

摘要:

目的：通过单侧咬合创伤方法建立大鼠颞下颌关节骨关节炎（temporomandibular joint osteoarthritis，TMJ-OA）模型，并观察髁突软骨的组织病理学变化。方法：将大鼠随机分为对照组和实验组，再分为4个亚组，即4、8、12、16周组，每组6只大鼠。用树脂将方弓丝粘接于实验组大鼠右侧上颌第一磨牙（牙合）面，垫高约0.5 mm。称量并记录各组大鼠第1、2、3、4、8、12、16周体质量，并于第4、8、12、16周分别取材，通过苏木精-伊红及番红O-固绿染色，检查、分析大鼠颞下颌关节髁突软骨的组织病理学变化，并测量各组大鼠髁突软骨各层厚度变化。结果：①在实验早期，咬合创伤对大鼠体质量增长影响较大（t1=4.757，P1=0.000；t2=3.096，P2=0.003）。②8周时，实验侧髁突软骨发生较明显组织病理学变化[组织学评分为（8.67±1.37），t=-7.267，P=0.000]，纤维层软骨出现水平裂隙，增殖层软骨细胞排列紊乱，呈早期骨关节炎样软骨病损。③咬合创伤对髁突软骨造成的病理损害程度与其作用时间相关，时间越长，病损越重。结论：采用单侧咬合创伤方法成功建立了大鼠颞下颌关节骨关节炎模型，且造模8周后可观察到早期的骨关节炎样病损表现，此模型可作为研究TMJ-OA早期病理机制的理想模型。

Abstract:

Objective：To establish the model of temporomandibular joint osteoarthritis（TMJ-OA） in rats induced by unilateral occlusal trauma，and to evaluate the histopathological changes of the condylar cartilage. Methods：The rats were randomly divided into two groups，the control group and the experimental group，and each group was divided into four subgroups（4，8，12 ，16 weeks group，6 rats in each group）. Metal-wire was attached to the right maxillary first molar by rein and the occlusion was elevated by 0.5 mm. The weight was recorded in 1，2，3，4，8，12，16 weeks after the operation. The rats were sacrificed at 4，8，12，16 weeks after occlusal trau－ma，respectively. The histopathological changes of condylar cartilage were evaluated by HE and safranin-O fast green staining，and the change of cartilage thickness was measured and analyzed. Results：①At the early stage of the operation，occlusal trauma had a great influence on the weight（t1=4.757，P1=0.000；t2=3.096，P2=0.003）. ②At the 8th week，the condylar cartilage of the experimental side showed obvious lesion of OA（Mankin score=8.67±1.37，t=-7.267，P=0.000）. There were horizontal fissures in fibrous cartilage. The chondrocytes were arranged irregularly in proliferating layer and showed the OA-like lesions. ③The histopathological damage caused by occlusal trauma to condylar cartilage was time-related. Conclusion：Model of TMJ-OA is successfully established in rats by unilateral occlusal trauma and the obvious pathologicalchanges are detected at 8 weeks. This could be a promising model for the study of the pathogenesisof TMJ-OA.