颞下颌关节盘前移位关节区组织病理变化的实验研究

目的通过建立关节盘前移位实验动物模型的方法,来研究人类关节盘前移位病变早期阶段的发展过程和病理学改变。方法１２只新西兰大白兔左颞下颌关节经实验诱导为关节盘前移位模型,右侧为手术对照组。于术后２４ｈ、１周、２周、３周、４周、１０周各处死２只,切取关节组织,ＨＥ染色,光镜观察。结果早期：关节结节、髁突关节软骨增生明显,髁突软骨下出血,骨组织内血管网消失;后期：髁突关节软骨、骨组织及滑膜出现骨关节炎（ＯＡ）样改变。结论实验诱导关节盘前移后关节区的病理学变化与人类相似;关节盘前移位关节区的创伤可引起关节骨关节炎样改变。     

兔关节盘前移位后髁突软骨PRG4 mRNA表达改变的研究

目的 分析兔颞颌关节盘前移位后髁突软骨PRG4 mRNA表达的动态改变及其意义。方法 62只日本大耳白兔,48只建立关节盘前移位的动物模型,分期处死。6只为手术对照组,8只为空白对照。合成兔PRG mRNA探针,原位杂交检测关节盘前移位后髁突软骨PRG4 mRNA表达的动态改变。结果 PRG4 mRNA表达于髁突全层软骨。关节盘前移位后,PRG4 mRNA表达一过性升高,8周后回落至正常。4只样本术区骨关节病样表现,软骨崩解区域PRG4 mRNA的表达水平显著下降。结论 关节盘前移位后,髁突软骨细胞PRG4 mRNA一过性升高以保护髁突软骨表层的完整性,促进滑液润滑,有利于实现关节的适应性改建。?     

透明质酸钠和泼尼松龙对兔颞下颌关节软骨损伤治疗效果的研究

目的 比较局部应用透明质酸钠和泼尼松龙对兔颞下颌关节软骨损伤的治疗效果。方法 选用成年健康新西兰大白兔27只,随机分成4组。第1组:兔颞下颌关节髁突软骨全层损伤后局部应用泼尼松龙(12.5 mg),10只;第2组:兔颞下颌关节髁突软骨全层损伤后局部应用透明质酸钠(5 mg),10只;第3组:兔颞下颌关节髁突软骨全层损伤手术对照组,5只;第4组:正常对照组,2只。分别于术后1、2、4、8、12周处死,对髁突软骨及其修复组织进行大体形态学及组织学检查。结果 第1、2组实验动物的髁突软骨损伤区为纤维结缔组织增生,术后12周时,损伤区充满致密的纤维结缔组织,胶原纤维排列有序,与关节面平行。修复组织的质量类似,但第2组髁突软骨的退行性改变较第1组明显减轻。结论 泼尼松龙和透明质酸钠都能促进髁突软骨损伤后的修复,在预防颞下颌关节软骨的退行性改变方面,透明质酸钠优于泼尼松龙。     

颞下颌关节盘摘除对骨膜移植修复髁突软骨缺损的影响

目的 :颞下颌关节紊乱综合征器质性病变的病例中 ,常可见关节盘及髁状突软骨严重破坏的情况 ,因而不得不行关节盘摘除术、髁状突高位切除术。为了寻求在关节盘摘除术后用骨膜移植修复髁状突软骨缺损的可行性 ,本实验将家兔的一侧关节的关节盘摘除后并造成 4mm× 3mm大小的髁状突软骨缺损区 ,用自体游离骨膜移植于软骨缺损区。术后 16周处死动物 ,对缺损区的新生软骨及邻近原正常软骨组织进行大体和组织学观察 ,并与未摘除关节盘组 (组Ⅱ )相对照。结果显示 :在关节盘摘除后 ,行游离骨膜移植修复髁状突软骨缺损效果较差 ,且易导致邻近原正常软骨的变性性改变     

生物活性玻璃陶瓷人工髁突置换对颞下颌关节盘及 …

目的：考察生物陶瓷人工髁突用于ＴＭＪ置换的可行性。方法；在杂种狗上建立髁突置换模型，采用Ｘ线、组织学方法观察术后１、３、５、１０个月关节腔、关节盘及关节突的改变。结果：虽然人工髁突具有良好的生物相容性及力学强度，但却可在植入早期引起滑膜充血、增生、５月以后关节盘增厚，关节内纤维组织增生及软骨岛形成，１０月关节腔完全被软组织充填，粘连，结论：这是生物陶瓷人工髁突表面的硬度及陶瓷微粒弥散入周围的组织。     

生物活性玻璃陶瓷人工髁突置换对颞下颌关节盘及关节结节影响的实验研究

目的 :考察生物陶瓷人工髁突用于TMJ置换的可行性。方法 :在杂种狗上建立髁突置换模型 ,采用X线 ,组织学方法观察术后1,3,5,10个月关节腔、关节盘及关节突的改变。结果 :虽然人工髁突具有良好的生物相容性及力学强度 ,但却可在植入早期引起滑膜充血、增生 ,5月以后关节盘增厚 ,关节内纤维组织增生及软骨岛形成 ,10月关节腔完全被软组织充填 ,粘连。结论 :这是生物陶瓷人工髁突表面的硬度及陶瓷微粒弥散入周围的组织。在未解决上述问题之前 ,临床上应用此方法应十分慎重     

兔颞下颌关节盘前移位后关节软骨细胞的凋亡及其意义

目的　观察颞下颌关节盘前移位动物模型的关节软骨细胞凋亡动态改变 ,探讨软骨细胞凋亡的意义。方法　日本大白兔 2 6只 ,实验组 2 0只行手术 ,在不打开颞下颌关节囊的情况下制成关节盘前移位动物模型 ,采用原位末端标记法 (TUNEL)观察术后不同病变时期关节区组织学的改变和软骨细胞凋亡的情况。结果　术后 1～ 2周为髁突软骨细胞凋亡的高峰期 ,集中于功能区的肥大层和增殖层。 4～ 6周进入关节改建期。结论　关节盘前移位后可激活软骨细胞的凋亡机制 ,启动关节软骨的适应性改建     

渐进性咬合紊乱对恒河猴颞下颌关节影响的扫描电镜观察

目的：探讨咬合紊乱是否可以独立造成颞下颌关节退行性变。方法：实验动物采用恒河猴2只，实验组1只，拔除一侧下颌和其对侧上颌第一磨牙，在拔牙间隙处各置一拉簧，使邻牙向拔牙间隙处倾斜，变与对颌牙紧密的尖窝接触关系为不密合的突面接触关系，8个月后取双侧髁状突、关节盘常规制备，喷金镀膜后扫描电镜观察。另1只动物作空白对照。结果：对照组髁状突和关节盘表面凝胶样物质覆盖，有明显的波纹，髁状突断面可见界限明显、有一定厚度的三层结构。实验组髁状突和关节盘，主要是髁顶附近内前向外后走行的一个区域，凝胶样物质卷曲、甚至丧失，髁状突表面出现纤维暴露区。断面显示，软骨变薄，蜂窝状软骨陷窝层局部不连续，关节盘中后带部分区域表面沟纹紊乱，在下表面后带观察到类似弹坑样变。结论：渐进性咬合紊乱可独立造成颞下颌关节退行性变。     

单侧个别牙短期[牙合]干扰对兔髁突表面超微结构的影响

目的:观察单侧个别牙短期干扰去除前后兔髁突表面超微结构变化情况。方法:12只5月龄雄性新西兰白兔被随机分为干扰A组(戴单冠2周)、干扰B组(戴单冠4周)、去除干扰A组(戴单冠4周后去冠休息2周)和去除干扰B组(戴单冠4周后去冠休息4周)4组,每组3只,其中施以实验因素2只,对照1只。扫描电镜下观察各组兔髁突表面超微结构特点。结果:对照兔髁突表面覆盖一层完整连续膜样凝胶样物质。干扰兔髁突表面凝胶样物质明显减少,表层胶原纤维部分暴露;前内侧或前外侧局部区域变化尤为显著,表现为凝胶样物质消失,表层胶原纤维完全暴露。去除干扰兔髁突表面凝胶样物质明显增多,分布不均匀,呈绸块样(去除干扰2周)和网膜样(去除干扰4周)。结论:单侧个别牙短期干扰影响兔髁突表面凝胶样物质的存在,破坏髁突表面凝胶屏障的完整连续性,使滑液保护、润滑和营养关节软骨及稳定关节的功能下降;在本实验周期内,去除干扰可促进髁突表面凝胶样物质的生成和膜性化修复,使滑液功能得以恢复。     

家兔一侧颞颌关节手术非手术侧髁状突表面扫描电镜观察

目的　观察一侧颞下颌关节手术对非手术侧颞颌关节的影响。方法　通过扫描电镜观察对比研究一侧家兔关节髁状突高位切除加关节盘摘除术后 ,对非手术侧颞颌关节髁状突表面的影响 ,并与相同月龄的正常家兔关节进行比较。结果　颞下颌关节髁状突高位切除加关节盘摘除术会对非手术侧关节产生影响 ,主要表现为髁状突表层结构遭到破坏 ,如网状胶原纤维暴露 ;凝胶样物质剥脱、堆积、表面裂缝、缺损和胶原纤维暴露、断裂及崩解等。结论　一侧颞颌关节手术可导致非手术侧颞下颌关节髁状突表层结构的退行性改变     

The effects of high molecular weight hyaluronic acid (Hylan G-F 20) on experimentally induced temporomandibular joint osteoartrosis: part II

The aim of this study was to determine the efficacy of Hylan G-F 20 on experimentally induced osteoarthritic changes in rabbit temporomandibular joint (TMJ). A 3 mg/ml concentration of sodium mono iodoacetate (MIA) had been injected into both joints of 24 rabbits to create osteoartrosis. The study group was injected with Hylan G-F 20 in one joint and saline in the contralateral joint as a control (once a week for 3 weeks). Histological changes in articular cartilage, osteochondral junction, chondrocyte appearance and subchondral bone were determined at 4, 6, and 8 weeks. Regarding cartilage, there was a statistically significant difference between the two groups at 4 weeks. Degenerative bony changes to subchondral bone were significantly higher in the controls. No statistical difference was found in the study group at 6 weeks. A positive correlation was found between osteochondral junction and subchondral bone in the study group at 8 weeks. The changes in chondrocyte appearance were significantly decreased in the study group at all follow-up times. Intra-articular injection of Hylan G-F 20 decreased cartilage changes in early stage TMJ osteoartrosis and clustering of chondrocytes showed the chondroprotective effects of Hylan G-F 20 caused by hypertrophic responses.     

Histopathological changes in rabbit craniomandibular joint associated with experimentally induced anterior disk displacement (ADD)

Several studies have shown that anterior disk displacement (ADD) of human temporomandibular joint (TMJ) can lead to cellular and extracellular alterations in the disk proper, bilaminar zone (BZ), condyle, articular eminence and synovial membrane. Due to lack of an animal model for this disease, it is not known whether the mechanical displacement of the disk could lead to the observed histopathological changes. The purpose of this experiment was to investigate the histopathological changes that occur in the rabbit craniomandibular joint (CMJ) following surgical induction of ADD. The right CMJ was exposed surgically and the discal attachments were severed except for the BZ attachments. Then the disk was displaced anteriorly and sutured to the zygomatic arch. The left joint served as surgical control. The CMJs were removed after 24 h, 1 week, 2 weeks or 6 weeks and stained with H&E or modified Masson stain. The results showed neovascularization, cell clustering and fibrillation of the displaced disk. The BZ showed marked fibrosis. The condyle showed subchondral hemorrhage and fibrosis followed by osteoarthritic changes in the articular cartilage. The articular eminence showed chondrocytic clustering and an increase in the amount of chon-droid bone. Synovial membrane exhibited marked hyperplasia. We concluded that surgical induction of ADD in the rabbit CMJ leads to cellular and extracellular alterations in the disk proper, BZ, condyle, articular eminence and synovial membrane similar to those described previously in human ADD. It appears that the mechanical trauma resulting from ADD could lead to a cascade of reparative and degenerative changes of the affected joints similar to those described for osteoarthritis.     

Influence of altered occlusal plane on rabbit temporomandibular joint cartilage

Background:  There is limited knowledge relating to the influence of mechanical stress on the temporomandibular joint (TMJ) and the degree of damage this stress can induce in the case of an altered occlusal plane on the extracellular matrix cartilage and chondrocytes. The aim of this study was to examine the histopathological influence of an altered occlusal plane on rabbit TMJ cartilage.
Methods:  Fifteen male Japanese white rabbits were used in this study. In 12 cases, the upper right and lower left teeth were ground to their cervical level so that the occlusal plane was tilted right side up. Their temporomandibular joints (TMJs) harvested at 3 days, 1, 2 and 4 weeks were analyzed immunocytochemically and immunohistochemically. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick endlabeling (TUNEL) method was used for immunocytochemical study to detect DNA fragmentation in chondrocytes. An immunohistochemical study was also performed to evaluate the metabolism of type 2 collagen in the extracellular matrix in the TMJ cartilage.
Results:  The number of apoptotic cells increased in all experimental animals. More apoptotic cells were observed in the articular eminences than in the condyles. The type 2 collagen-positive area in the condyles was reduced at the beginning but recovered within 4 weeks, and remained small throughout this experimental period in the articular eminences.
Conclusions:  These findings suggest that histopathological changes occurred in response to alteration of the occlusal plane. The influence decreased as the occlusal plane recovered in the condyles, but the immunocytochemical and immunohistochemical influence continued in the articular eminences.     

Temporomandibular joint: surgically created disk displacement causes arthrosis in the rabbit.

To document a causal relationship between temporomandibular joint disk displacement and arthrosis, the disk was surgically displaced in one temporomandibular joint in each of three rabbits. The rabbits were sacrificed after 4 weeks and the mandibular condyles were studied radiographically and histologically. All three joints that underwent disk displacement had radiographic and histologic evidence of arthrosis, which included erosion of the bone, irregularity and fissure formation of the articular soft tissue cover, disruption of the subchondral layer of cartilage cells, and chondrocyte proliferation. No radiographic or histologic changes occurred in the joints that were untouched. The results suggest that surgically created disk displacement can cause arthrosis in the temporomandibular joint of the rabbit.     

A repetitive,steady mouth opening induced an osteoarthritis-like lesion in the rabbit temporomandibular joint

Although excessive mechanical stress is assumed to be one of the factors contributing to pathogenesis of temporomandibular joint (TMJ) osteoarthritis (OA), no pure mechanical-stress-induced OA model has been developed without surgical manipulation or puncture of the joint cavity. The purpose of this study was to establish a genuine mechanical-stress-induced OA model of the rabbit TMJ. In the experimental rabbits, repetitive, forced jaw-opening, 3 hrs/day for 5 days, was applied with the use of a general anesthesia protocol. By histological assessment of the TMJ articular tissues, partial eburnation of the articular cartilage, reactive marginal proliferation of the articular cartilage chondrocytes, and nested proliferation of chondrocytes in the subchondral bone area were observed at 7 days after the repetitive, forced-jaw-opening period. These results suggest that the repetitive, forced-jaw-opening protocol without surgical intervention can induce evident OA-like lesions in the rabbit TMJ, and this OA model may greatly contribute to the elucidation of the cartilage degradation mechanism in TMJ OA.     

兔颞下颌关节盘前移位的X线研究

目的　通过影像学检查了解颞下颌关节盘前移位的病理变化过程,证实关节盘前移位与退行性改变之间的关系。方法　在手术组动物一侧关节区显露颞骨颧突根部,用丝线垂直穿过关节盘前带的延伸部并拉缝线向前并固定,使颞下颌关节盘前移位。手术对照组的手术步骤与手术组相同,但不缝合关节盘前带的延伸部,也不将关节盘位向前方。正常对照组5只,手术组和手术对照组动物术后1、2、4、8、10、12和16周分别处死。拍摄关节X线片,观察38只兔颞下颌关节X线表现。将兔左、右关节区锯成组织块,肉眼观察兔关节盘的位置。结果　手术组关节盘位置与形态均发生了改变,13侧为部分关节盘前移位,完全性关节盘前移位为11侧,关节盘穿孔为9侧。部分关节盘前移位出现关节间隙狭窄或消失,髁状突骨密度增高。完全性关节盘前移位与关节盘穿孔表现为髁状突骨质增生、破坏及肥大,关节结节磨平以及硬化。结论　颞下颌关节盘前移位可导致关节骨质改变。完全性关节盘前移位和关节盘穿孔与骨关节病的关系密切。     

大鼠多发性关节炎早期颞下颌关节的组织病理学研究

目的　观察大鼠多发性关节炎 (polyarthritis,PA)早期颞下颌关节 (temporomandibularjoint,TMJ)的组织病理学变化 ,为研究类风湿关节炎 (rheumatoidarthritis,RA)早期对TMJ的影响提供实验依据。方法　用福氏完全佐剂建立大鼠PA模型 ,观察其踝关节和TMJ的组织病理学变化。结果　①大鼠PA时 ,踝关节体积显著增大 ,关节指数明显增高 ;踝关节滑膜组织增生 ,炎性细胞浸润 ,关节软骨及骨质受侵蚀 ,关节腔炎性渗出明显。②大鼠PA时 ,双侧TMJ均可见滑膜细胞显著增生 ;髁突表层胶元纤维松解 ,软骨细胞变性 ;关节腔可见蛋白渗出 ,细胞脱落 ,局部呈纤维性粘连。结论　大鼠PA早期双侧TMJ即有明显的炎性病变。建议临床医生对RA患者应注意其TMJ的早期检查与防治     

Effect of ibuprofen on the healing and remodeling of bone and articular cartilage in the rabbit temporomandibular joint.

The purpose of this study was to determine the effect of ibuprofen on the healing and remodeling of bone and cartilage in the temporomandibular joint of the rabbit. Forty-two rabbits were operated on to create a groove and a hole in the articular surface of both the right and left mandibular condyles. Following surgery, the animals were divided into three groups. Group A (12 rabbits) was used as a control and the animals did not receive any medication. Group B (15 rabbits) was given a daily dose of 17 mg/kg of ibuprofen. Group C (15 rabbits) was given a daily dose of 34 mg/kg of ibuprofen. All animals were killed after 4 weeks. The 84 condyles were examined clinically and histologically. Statistical analysis showed a highly significant difference in the healing of bone and cartilage between groups A and C (P less than .01) and a significant difference between groups A and B (P less than .05). The results of this study indicate that ibuprofen has an adverse effect on the healing of bone and cartilage in the temporomandibular joint of the rabbit.     

颞下颌关节骨关节病动物模型的构建研究

目的建立能够很好地反映颞下颌关节骨关节病(temporomandibular joints osteoarthritis,TMJOA)的发病情况并为治疗打下良好基础的动物模型。方法选择37只新西兰白兔,分为实验组、阴性对照组和健康对照组,通过颞下颌关节(TMJ)内注射Ⅱ型胶原酶来诱导兔产生TMJOA,并动态全程观察4、8、12、16、20、24周兔颞下颌关节大体和组织病理学的发生、发展过程。结果随时间的延长,病变先是表现为逐渐加重,以后出现缓解趋势,实验组中均于4周后出现较明显的骨关节病损,其中12周组达到病变高峰,20、24周组出现局部修复现象。结论胶原酶注射后的兔颞下颌关节大体和组织病理学改变与人TMJOA的基本病理改变一致,具有良好的可比性和相似性,成功地构建了一种TMJOA的动物模型。