关节盘穿孔对兔颞下颌关节影响的扫描电镜观察

Ultrastructure changes of temporomandibular jointa temporomandibular joint after disc perforation:a scanning electron microscopic study

目的研究兔关节盘穿孔后对颞下颌关节(TMJ)髁状突和关节盘表面超微结构的影响。方法12只3～4月龄的新西兰白兔,随机均分为实验组和对照组。以质量分数为50mg/ml的氯胺酮溶液按1ml/kg对实验动物进行肌注麻醉,对照组于无菌条件下先后暴露左右侧关节盘,实验组并以特制的穿刺针于关节盘后外侧部制作直径为2.6mm的穿孔。分别于术后12、24和36周完整取出双侧TMJ,扫描电镜观察关节盘和髁状突的变化。结果扫描电镜下可见关节盘穿孔后关节表面凝胶状物质不完整,关节盘及髁状突表面均出现明显的退行性改变:凝胶样物质掀起、剥脱,胶原纤维疏松、暴露、断裂、排列紊乱。结论关节盘穿孔可以引起TMJ表面退性行改变。

Objective To observe the ultrastructure changes of temporomandibular joint （TMJ） following disc perforation in rabbits. Methods 12 adult New Zealand white rabbits （age：3 - 4 months, weight：2.0 - 2.5 kg） were randomly divided into normal control group （n=6） and experimental group （n=6）. These rabbits were injected with ketamine hydrochloride for generation anesthesia. TMJ discs in right and left were exposed sterilely in normal control group and disc perforations with 2.6 mm diameter were created with special acus in experimental group. Every group was sacrificed respectively at 12, 24 and 36 week postoperatively and bilateral TMJs were removed entirely, then uhrastructure changes of TMJ were observed by scanning electron microscope. Results Scanning electron microscope revealed that the amorphous components on the surface of TMJ were not in their integrity in experimental group. The surface of condyle and disk of the experimental group were destroyed： the amorphous components were twisted or disappeared and the underlaying collagen fibers were loosed, exposed, ruptured and ranked disorderedly in some place. Conclusions The findings suggested disc perforations in rabbits could result in degenerative changes of the TMJ.