Macroscopic, microscopic and radiologic assessment of the condylar part of the TMJ in elderly subjects. An autopsy study

Thirty-seven temporomandibular joints were examined in an autopsy study. The sizes and forms of the condyles were found to be in good agreement with earlier presented results. Structural changes were found in 16 condyles (38%) in the macroscopic examination, while radiographically diagnosed erosions were found in 8 (21%). Twenty-two (59%) of the discs examined had either perforations, roughness or attenuations. Anterior disc position was found in 3 discs, and always in combination with a perforation of the disc.     

Histopathological study of human TMJ perforated discs with emphasis on synovial membrane response

Fifteen perforated TMJ discs from human cadavers were studied histologically to examine the synovial membranes and to compare the findings with previous experimental results in monkeys. There were four with perforations in the bilaminar zone (these four discs were displaced anteriorly), three in the medial third of the disc, and eight in the lateral third of the disc. Histopathologically, there was an increase in vascularity and strong methyl pyronine-positive cellularity around the margins of the perforations. A young, loose, collagenous tissue lined the lateral margins of the perforated discs. Increased fibrous tissue content of the synovial subintimal territorial matrix and osteochondroid metaplasia were also seen. Severe synovial hyperplasia was visible in all joint recesses, but was greatest within those associated with displaced discs. There was patchy distribution of acidic glycoproteins, especially in the lateral parts of the perforated discs. As in the animal studies, human TMJ disc perforation was associated with a vigorous synovial reaction that was seen to form lateral bridges along the margins.     

颞下颌关节盘前移位关节盘及盘后区超微结构变化的实验研究

目的通过建立关节盘前移位实验动物模型的方法,研究颞下颌关节盘前移位后关节盘及盘后区早期超微结构的变化。方法10只兔左侧关节经手术诱导为关节盘前移位模型,右侧为手术对照组;2只为正常对照组。术后24小时、1周、2周、3周、4周,麻醉下活体各切取2只手术组实验动物同一部位的关节盘和关节盘后区组织,制成透射电镜标本观察。结果关节盘组织中软骨样细胞逐渐增多,细胞周围的淡区逐渐变小并消失,胞浆中微丝增加,胶原纤维间排列紊乱数量减少,并见新生毛细血管及神经纤维,最后软骨样细胞转化为纤维母细胞和肌纤维母细胞。盘后区早期出现幼稚的软骨样细胞,有排列相对致密的胶原纤维,最后转化成类似于关节盘样组织。结论颞下颌关节盘前移位后,关节盘失去纤维软骨盘的特性转化为纤维结缔组织;盘后区则由疏松的结缔组织变成纤维软骨盘样组织。     

The anterosuperior insertion of the temporomandibular joint capsule and condylar mobility in joints with and without internal derangement: a double-contrast arthrotomographic investigation

The insertion of the anterior temporomandibular joint capsule at the temporal bone constitutes an anatomic boundary of the joint. When condylar translation exceeds this site, the joint is classified as hypermobile. In this study, the distance from the apex of the articular eminence to the antero-superior capsule insertion was assessed in double-contrast arthrotomograms from 192 joints with and without disc displacement. Maximum condylar translation was also measured. The insertion point of the antero-superior capsule was, on the average, located 4.4 mm (SD, 1.7 mm) anterior to the apex of the eminence, regardless of disc position. Hypermobility was present in 56 joints. Sixty-eight percent of the hypermobile joints had a reducing disc and 62% of all the joints with a reducing disc were hypermobile. In joints with permanent disc displacement, the condyle generally was halted posterior to the apex of the eminence, but could pass extensively anterior to it. Condylar hypermobility thus does not exclude the presence of a permanently displaced disc. In 71% of patients with hypermobility, the condition was bilateral. Because of the close topographic relationship between the joint and nerve branches in the anterior vicinity of the joint, a hypermobile condyle may mechanically irritate the masseteric and deep posterior temporal nerve branches.     

Morphometric investigation of condylar cartilage and disc thickness in the human temporomandibular joint: significance for the definition of ostearthrotic changes

106 human TMJ specimens from 53 individuals (age: 65–85 years) were examined macro- and microscopically and measured for discal and condylar cartilage thickness at five points defined on a mediolateral axis along the middle dense pan of the disc. 27% of the discs showed lateral and laterocentral perforations. In 8% the lateral portion was thinned down to a translucent layer. 62% showed no gross destruction or deviation in shape and thickness. The remaining 3% displayed extensive destruction and their condyles were osteoarthrotic. All discs showed a significant decrease in thickness from their medial towards their lateral portions. The condyles displayed either a smooth articular surface (16%) or an irregular and progressively remodelled surface (81%) with histologically normal fibrocartilage. The condylar cartilage did not show a significant gradient of thickness in amediolateral direction. The results support our previously developed working hypothesis, that the joint is seemingly loaded along its entire articular surface and that a lateral disc perforation in older individuals can be due to a physiological process of wearing rather than to a pathological sequel of functional disorders.     

颞下颌关节盘前移后双板区改建的实验研究

目的:探讨关节盘前移后双板区的适应性改建。方法:日本大白兔30只,先制作成关节盘前移位动物模型,定期处死,取关节标本作HE染色、阿尔辛蓝、间苯二酚-品红染色、细胞凋亡检查和蛋白多糖含量测量。结果:在关节盘移位的初期,双板区即发生细胞凋亡,胶原纤维和弹力纤维排列紊乱、断裂;蛋白多糖先是急剧下降,然后缓慢上升。4周后,双板区内可出现软骨样细胞或典型的软骨组织。结论:双板区在关节盘移位后会进行重构,使之成为类似纤维软骨样组织。     

Osteoarthrosis of the temporomandibular joint following experimental disc perforation in Macaca fascicularis

The aim of this experiment was to study the sequela of experimental temporomandibular joint (TMJ) disc perforation. Each TMJ of four Macaca fascicularis adult monkeys was surgically exposed, and a 4- to 6-mm perforation at the posterolateral portion of the avascular disc was produced by electrosurgery. Four monkeys were used as controls. The animals were killed 11 weeks (two experimental and two controls) or 12 weeks (two experimental and two controls) after disc perforation. The perforations were increased in size in five joints, and healed in one joint. In addition, two joints of one animal showed complete loss of the disc, denudation of articular surfaces, and bone-to-bone contact. In contrast to control joints, the experimental joints exhibited the following changes histopathologically: thick, highly cellular and fibrillated fibrous coverings of articular surfaces (five joints); marked hyperplasia of synovial membrane; migration of synovial cells on the surfaces of the disc and margins of perforation; multiple adhesions of disc to articular surfaces; increase in cellularity and vascularity of discs; and chondrocytic clustering in temporal fibrous covering; and osteophytes of condylar and temporal components and focal or complete denudation of articular surfaces (2 joints). Most of these changes were consistent with the diagnosis of osteoarthritis. From this study, one can conclude that disc perforation can lead to osteoarthritis.     

颞下颌关节盘前移位和穿孔的关节内窥镜研究

目的 :探讨颞下颌关节内窥镜下颞下颌关节盘移位和关节盘穿孔的病理改变特征。方法 :76例 84侧临床诊断为颞下颌关节盘前移位以及关节盘穿孔的病例进行颞下颌关节内窥镜检查。结果 :可复性关节盘前移位的病例出现滑膜炎 ,关节腔内有絮状物 ,关节结节表面有纤维形成。不可复性关节结节表面纤维形成 ,关节软骨软化 ,软骨剥脱 ,同时伴有纤维粘连。关节盘穿孔大多数位于双板区与后带。关节盘穿孔出现滑膜增生 ,关节窝及关节结节表面纤维形成 ,软骨剥脱甚至骨质暴露。结论 :关节内窥镜检查可诊断关节盘前移位与关节盘穿孔 ,并能发现病理性改变 ,如滑膜炎 ,滑膜增生 ,纤维变性 ,软骨软化 ,关节内粘连等。在不可复性盘前移位病例中发现关节退行性改变 ,关节盘穿孔为严重的骨关节病。     

The posterior segment of the temporomandibular joint capsule and its anatomic relationship.

PURPOSE: The aim of this work was to clarify the arrangement of the posterior segment of the temporomandibular joint capsule and its pertinent relationships. MATERIALS AND METHODS: The temporomandibular region was dissected bilaterally in 20 adult cadavers. Natural stained latex was injected into 16 cadavers through the external carotid artery to facilitate the dissection of the arterial vessels. RESULTS: The posterior segment of the joint capsule is made up of the so-called "bilaminar zone" of the articular disc. The upper internal portion of the posterior segment of the capsule was reinforced by the discomalleolar ligament. The retroarticular space was filled with loose connective tissue and the anterior branches of the anterior tympanic artery were distributed throughout the posterior segment of the joint capsule. CONCLUSION: The posterior segment of the temporomandibular joint capsule corresponds to the bilaminar zone of the articular disc. The structures of the retroarticular space are extracapsular.     

颞下颌关节骨关节病髁突组织细胞凋亡的研究

目的研究颞下颌关节骨关节病骸突组织中软骨细胞凋亡发生的特点,探讨细胞凋亡在颞下颌关节骨关节病发病机制中的作用。方法通过手术切除部分关节盘的方法建立颞下颌关节骨关节病动物模型,15 d-6个月内采用TUNEL法标记裸突各相应时段的凋亡细胞,结合相应组织学变化,观察、分析颞下颌关节骨关节病裸突组织中细胞凋亡发生的特点。结果关节盘损伤后软骨产生明显应激性修复增殖反应时,凋亡细胞主要集中于关节表面的纤维层中;随着关节软骨和骨组织不断改建,软骨组织中逐渐出现大量的细胞凋亡现象,主要发生于表面纤维层与增殖层,尤其集中在软骨细胞簇中;在软骨组织消耗严重时,浅表区域内的细胞凋亡现象逐渐减少,肥大钙化层中出现了较多的凋亡细胞。结论颞下颌关节骨关节病骸突软骨组织中存在过量凋亡的现象,软骨细胞异常增殖与过度凋亡导致软骨基质自身调节机制的破坏可能是骨关节病发生的重要原因之一。     

自体耳廓软骨瓣置换或重建颞下颌关节盘——临床疗效评价

目的　为了对己严重病变的关节盘进行置换及对关节强直进行重建关节盘 ,本文报道耳廓软骨移植的手术方法和临床疗效 ,并结合文献报道中的有关资料进行讨论。方法　对 4侧结构紊乱、4侧骨关节病、2侧滑膜软骨瘤病及 3侧关节强直 ,共 13侧颞下颌关节 ,用自体耳廓软骨瓣置换或重建关节盘 ,其中 ,6例合并应用关节刨削术 ,2侧用颞深筋膜瓣重建关节外侧囊 ,1侧耳廓软骨瓣复合颞深筋膜修复关节盘以获得足够的厚度。结果　随访期 1～ 13月 ,所有软骨瓣无感染 ,均成活 ,临床疗效满意 ,供区无或轻微变形。结论　在形态和厚度方面 ,人类的耳廓软骨瓣与关节盘较相似 ,是一种置换或重建关节盘的较好材料     

Disc-like changes and type II collagen mRNA expression in the bilaminar zone of rabbit temporomandibular joint following disc displacement]

OBJECTIVE: To study the adaptive alteration in bilaminar zone of rabbits' temporomandibular joint following disc displacement. METHODS: Twenty-six Japanese white rabbits were used in this study. Among these rabbits,6 were used as controls. The right discs of other 20 rabbits were displaced anteriorly by operation. Four of these rabbits were killedatn 1, 2, 4, 6 and 8 weeks respectively after surgery. The TMJS were studied by HE staining, Alcin bluen staining and in situ detection of type II collagen mRNA expression. RESULTS: There appeared cartilage metaplasia after one week following disc displacement. Typical chondrocytes could be found in the bilaminar zone. The new chondrocytes expressed type II collagen. CONCLUSIONS: The bilaminar zone of TMJ will be remodeled following disc displacement and become a disc-like tissue to function as a disc.     

Histological changes in temporomandibular joints from elderly individuals. An autopsy study

Our aim was to study microscopically the disc position and structural tissue changes such as disc perforation of the temporomandibular joint (TMJ). An autopsy material comprising the right and left TMJ from 21 individuals with a mean age of 75 years was studied. Anterior disc position was found in 11 joints from 8 individuals. Discs in anterior position were most often of even thickness or convex, whereas most discs in normal position were concave. Perforation was found in the central dense part of the disc in one joint and in the posterior disc attachment of five joints. The latter five discs were in anterior position. Of the five joints with anterior disc position and perforation of the posterior attachment, four joints showed marked structural changes also in the condyle and temporal component. Such changes were found only in one of six joints with anterior disc position but without perforation. No signs of cellular inflammation were observed in any of the joints. Fibrous ankylosis was found in four joints from three individuals. Joints with anterior disc position comprised more than one fourth of the examined joints. In some of these joints there were no structural changes; in other of these joints disc perforation was combined with convex disc form and marked structural changes of the condyle and temporal component.     

颞下颌关节骨关节病动物模型的建立及组织病理学观察

目的 建立稳定的颞下颌关节骨关节病动物模型。方法 通过外科手术切除部分关节盘的方法，在成年兔上建立较为稳定的颞下颌关节骨关节病动物模型；分别于术后第15天、1个月、2个月、3个月、4个月、5个月和6个月将实验兔处死，取实验侧髁突组织进行组织病理学观察；1％甲苯胺蓝染色，观察病变髁突组织中蛋白多糖的分布范围与水平变化。结果 本研究中的颞下颌关节骨关节病模型从组织病理学上先后观察到了关节盘损伤后早期关节软骨的应激性修复增殖，中期软骨基质渐进性损耗，后期软骨基质损耗丧失、纤维组织修复覆盖及骨赘形成等软骨退行性变过程。甲苯胺蓝染色显示，病变早期肥大增厚的软骨组织中蛋白多糖含量降低，且分布不均匀；病变晚期的髁突较深层软骨组织中仍可见有蛋白多糖的合成与分布。结论 本研究所建立的颞下颌关节骨关节病动物模型能较好地模拟骨关节病的组织病理学变化过程，且具有结果稳定、可重复性好的优点。     

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。     

The efficacy of anterior repositioning splint therapy studied by magnetic resonance imaging

Magnetic resonance images (MRIs) were obtained of 52 temporomandibular joints (TMJs) of 30 patients with TMJ disease, before insertion of an anterior repositioning splint. Ten TMJs showed a normal disc-condyle relationship. Pathological findings were partial or complete anterior disc displacement with disc reduction (n = 18), without (n = 7), or with partial reduction (n = 4) or non-reducing joints combined with osteoarthrosis (n = 13). Associated clinical findings were joint clicking, painful TMJ movements with or without condyle limitation, deviation, or crepitus. The clinical evaluation when compared with the MRIs correlated in 75 per cent of cases. Immediate post-insertion MRIs showed recapture of discs with a protrusive splint in 15 out of 18 reducing displacements. Recapture of the disc was seen in only two out of four joints with anterior disc displacement with partial disc reduction. There was no recapture in non-reducing joints. In severe cases of internal derangement with a wide range of disc displacement combined with changes of the osseous joint surfaces, the recapturing of the articular disc with an anterior repositioning appliance was unsuccessful (0 of 13). The follow-up for pain relief after one week showed a significant reduction of symptoms, despite the fact that recapture of the dislocated disc occurred in only 17 of the 42 pathological TMJs. The possibility for disc recapture depends on the disc-condyle position and configuration, the integrity of the posterior attachment, and the degree of degenerative changes of the intra-articular structures, such as osteophytosis, condylar erosion, or flattening of the articular disc. This diagnostic information influences the method of treatment of TMJ disorders. In non-reducing joints or in the later stages of internal derangement of the TMJ, it is not possible to achieve a normal disc-condyle relationship using protrusive splints.     

翼外肌对可复性颞下颌关节盘前移位的作用机制

目的 分析可复性关节盘移位中翼外肌作用下颞下颌关节的应力分布情况。方法 利用已建立的可复性关节盘前移位颞下颌关节数字化仿真模型,在单纯翼外肌加载下进行生物力学分析。结果 关节盘应力集中于关节盘中间带偏外侧区域;髁突及关节窝应力主要集中于与关节盘相接触的功能面。在颞下颌关节盘的位移分布中,从关节盘前带至关节盘中间带,位移趋势逐渐增大,关节盘中间带与关节盘后带之间出现位移撕裂带,从关节盘中间带至关节盘双板区位移逐渐递减;而颞下颌关节整体位移最大值出现在关节囊前份的翼外肌上头附着区。结论 在可复性关节盘前移位中翼外肌可导致关节盘中间带偏外侧区域的应力集中,可能导致此区域关节盘变薄、穿孔甚至撕裂。     

牙颌面专用CT颞下颌关节造影的临床应用

目的　探讨牙颌面专用CT颞下颌关节 (temporomandibularjoint ,TMJ)造影对关节盘移位及关节骨结构的诊断效果。方法　对 10 9例 (119侧 )TMJ行牙颌面专用CT关节造影检查 ,将关节盘移位分为 5型 ,髁突骨质改变分为 4型。结果　① 119侧关节均有不同类型的关节盘移位 ,其中 84侧仅有关节盘前移位 ;另 35例则为关节盘旋转移位和侧向移位。②骨关节病的发生率 :男性、女性分别为 6 0 0 %和 6 1.7% ;骨关节病的发生率与关节盘移位类型无关 (χ2 =1.5 6 ,P >0 .0 5 )。③ 73侧骨关节病关节中 ,4 9侧 (6 7.1% )病变发生于髁突外侧 ,8侧病变发生于髁突内侧 ,另有 5侧髁突骨质改变部位不能确定。结论　TMJ造影牙颌面专用CT技术可同时多层面显示关节盘及关节骨性结构的病变 ,尤其是可对关节盘旋转移位及侧向移位、关节盘穿孔等作出准确诊断 ,因而明显优于常规关节造影     

Transmission electron microscopic and light microscopic study of condylar and joint disk in TMJ disturbance syndrome

Temporomandibular joint disturbance syndrome (TMJDS) is a complex disease. Its etiological factors and pathologic nature are not clear still. After studying the condyles and discs of 3 normals and 14 TMJDS patients by transmission and scanning electron microscopy and light microscopy, we found: The pathologic changes of TMJDS are similar to those of osteoarthritis. These changes may be associated with the microtrauma in TMJ. There are some repair reactions after destruction of the articular cartilage. The destruction of fibrils is one of the main destruction in TMJDS. The changes of bilaminar zone may be one of the causes of treatment failure by conservative methods in some patients.     

兔颞下颌关节盘移位与骨关节病关系的评价

目的评价颞下颌关节盘移位与骨关节病的关系。方法通过手术方法将２５只大耳白兔的颞下颌关节盘前移，术后１、２、４、８、１２周进行组织病理学检查。结果１１侧手术关节为部分关节盘前移位，８侧为完全性关节盘前移位，６侧为关节盘穿孔。部分关节盘前移位出现早期退行性改变和后期生理性改建，完全性关节盘前移位和关节盘穿孔出现退行性改变和严重的骨关节病。结论颞下颌关节盘前移位的程度与骨关节病有关，关节盘前移位越明显，越易出现骨关节病