Zhu T M, Luo P, Peng S S, Xu J
Department of Oral and Maxillofacial Surgery, Stomatological Hospital of Chongqing Medical University & Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences & Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing 401147, China.
Zhonghua Kou Qiang Yi Xue Za Zhi. 2021 Jan 9;56(1):86-93. doi: 10.3760/cma.j.cn112144-20200421-00223.
To establish the animal model of temporomandibular joint osteoarthrosis (TMJOA) in rats induced by perforation of articular disc and evaluate the morphological characteristics and histopathological changes of the condyle of temporomandibular joint (TMJ). Eight male SD rats, purchased from Chongqing Medical University, were marked from No. 1 to No. 8 according to a random number table. The eight numbered rats were then arranged according to their sizes from large to small. The first four rats were divided into the one-week group, while the last four were divided into the four-week group. In order to simulate a TMJ disc perforation, an oblique incision was created along the zygomatic arch of the left side (the model side) making the TMJ superior joint space exposed. The left disc was pulled out and artificially perforated by a dental round bur with 1.5 mm diameter at the postmedian part of TMJ disc. The disc of the right side (the control side) was kept intact. The rats were randomly euthanized respectively at 1 week or 4 weeks (n=4 for each time point) for further study. Morphological observation and imaging examination were used to assess the degree of articular cartilage degradation and the loss of subchondral bone. Immunohistochemicalstaining (IHC), safranin O and fast green staining, tartrate-resistant acid phosphatase (TRAP) staining and haematoxylin staining were performed to evaluate the histopathological changes of condylar cartilage. In the morphological observation, significant redness and swelling were observed on the model side of the 1-week-group and the typical beak-like change of osteoarthropathy was observed on the model side of the 4-week-group. The heights of condylar process on the model sides in the 1-week-group and 4-week-group [(2.73±0.14) and (2.49±0.25) cm, respectively] were significantly lower than that in the control side [(3.30±0.09) and (3.30±0.12) cm, respectively] (<0.01). Imaging examination showed obvious damage in trabecular microstructure on the model side of the 4-week-group. Safranin O and fast green staining showed that the amounts of proteoglycan on the model sides of the 1-week-group and the 4-week-group were significantly lower than that on the control sides (<0.01). TRAP staining showed that the numbers of osteoclasts on the model side of the 1-week-group and the 4-week-group was significantly higher than that on the control sides (<0.01). IHC staining and Haematoxylin staining showed that the mean optical densities of collagen on the model side of the 1-week-group and the 4-week-group was significantly reduced compared with that on the control sides (P<0.01), while the mean optical densities of matrix metalloproteinase increased significantly (<0.01). After making a articular disc perforation, the condylar cartilage on the model side presented typical TMJOA pathological changes.
建立关节盘穿孔诱导的大鼠颞下颌关节骨关节炎（TMJOA）动物模型，并评估颞下颌关节（TMJ）髁突的形态学特征和组织病理学变化。从重庆医科大学购买8只雄性SD大鼠，根据随机数字表从1到8进行标记。然后将这8只编号的大鼠按大小从大到小排列。前4只大鼠分为1周组，后4只分为4周组。为模拟TMJ盘穿孔，沿左侧（模型侧）颧弓做斜切口，暴露TMJ上关节腔。将左侧关节盘拉出，用直径1.5mm的牙科圆钻在TMJ盘后中部人工打孔。右侧（对照侧）关节盘保持完整。分别在1周或4周时将大鼠随机处死（每个时间点n = 4）用于进一步研究。采用形态学观察和影像学检查评估关节软骨退变程度和软骨下骨丢失情况。进行免疫组织化学染色（IHC）、番红O和固绿染色、抗酒石酸酸性磷酸酶（TRAP）染色和苏木精染色以评估髁突软骨的组织病理学变化。在形态学观察中，1周组模型侧可见明显红肿，4周组模型侧可见典型的骨关节炎喙状改变。1周组和4周组模型侧髁突高度[分别为(2.73±0.14)和(2.49±0.25)cm]显著低于对照侧[分别为(3.30±0.09)和(3.30±0.12)cm](<0.01)。影像学检查显示4周组模型侧小梁微结构明显受损。番红O和固绿染色显示，1周组和4周组模型侧蛋白聚糖含量显著低于对照侧(<0.01)。TRAP染色显示，1周组和4周组模型侧破骨细胞数量显著高于对照侧(<0.01)。IHC染色和苏木精染色显示，1周组和4周组模型侧胶原平均光密度与对照侧相比显著降低(P<0.01)，而基质金属蛋白酶平均光密度显著增加(<0.01)。关节盘穿孔后，模型侧髁突软骨呈现典型的TMJOA病理变化。
