Sound analysis of temporomandibular joint internal derangements with phonographic recordings

STATEMENT OF PROBLEM: Temporomandibular joint (TMJ) sound recordings could be analyzed to assess the state of TMJ internal derangements. PURPOSE: The aim of the study was to assess the value of sound analysis in the diagnosis of the type of the TMJ internal derangements. MATERIAL AND METHODS: After clinical and radiologic examinations, phonographic sound recordings on mandibular excursions were obtained in 52 patients with TMJ internal derangements and 12 control individuals. Sound correlations were made on the basis of opening-closing, protrusive-retrusive, and lateral excursions of the mandible. RESULTS: Clicking was a consistent finding of anterior disc displacement with reduction, whereas crepitation was found in varying degrees in anterior disc displacement and osteodegenerative arthritis. Silent TMJs were the feature of normal TMJs, except for the situations of acute lock. Although in 29 TMJs opening click was followed by a closing click (reciprocal clicking), 46 TMJs with opening click also had clicking on protrusion. On the other hand, 19 TMJs with opening click also had clicking on ipsilateral motion, and 40 TMJs with opening click had clicking on contralateral motion of the mandible. The sound patterns were found to be similar in opening-protrusive clicks and opening-contralateral clicks. The lack of protrusive clicking in the presence of opening click was considered an indication of late disc reduction on opening. Crepitation was observed in advanced cases of TMJ internal derangements. CONCLUSION: Within the limitations of this study, the results suggest that TMJ sound analysis on mandibular excursions was indicative for diagnosis and establishment of severity of TMJ internal derangements. Clicking and crepitation may be looked on as signs of abnormal joint disorder, clicking indicating anterior disc displacement with reduction, and crepitation, indicating progression from anterior disc displacement without reduction to osteodegenerative arthritis.     

The relationship between bone marrow edema and bone changes in the mandibular condyle: A longitudinal study with MR imaging

PurposeDecreased signal intensity on T1- or proton-density weighted magnetic resonance imaging (MRI) and increased signal intensity on T2-weighted MRI in the bone marrow space are thought to reflect bone marrow edema (BME). The purpose of this study was to determine whether condyle BME is associated with condyle bone changes.MethodsThe subjects were 57 patients [65 temporomandibular joints (TMJs)] with TMJ disorders showing condyle BME on initial MRI. Condyle bone changes were compared between TMJs that showed a persistent BME pattern (group P, 43 TMJs in 40 patients) and those that showed normal bone marrow signals, indicating disappearance of BME (group D, 21 TMJs in 22 patients) on follow-up MRI.Results(1) In TMJs with a condyle with a normal shape on initial MRI, condyle bone changes were present in 53.9% of TMJs in group P in follow-up MRI, whereas the normally shaped condyle remained in all TMJs in group D. (2) In TMJs with condyle erosion on initial MRI, condyle erosion was also present in 35.7% of TMJs in group P in follow-up MRI, but had disappeared in all TMJs in group D. (3) In TMJs with condyle osteophytes on initial MRI, erosion was present in 22.2% of TMJs in group P, whereas osteophytes remained in all TMJs in group D.ConclusionsThe longitudinal study showed that condyle BME is associated with condyle bone changes and may cause condyle erosion.     

Functional disturbances of the masticatory system related to temporomandibular joint involvement by rheumatoid arthritis

Several theories have been proposed concerning the aetiology of dysfunction of the temporomandibular joint (TMJ). To analyse the relationship of radiographic changes to clinical signs and symptoms of TMJ dysfunction, the present study was conducted in subjects highly predisposed to TMJ involvement, i.e. in patients with rheumatoid arthritis (RA). The aim of the study was to estimate the frequency of disturbances in the masticatory system of RA patients. In addition, the relationship between TMJ abnormalities and the signs and symptoms of dysfunction was investigated. The study consisted of sixty patients with RA and forty control subjects. Asymptomatic subjects were more frequent in the RA group than in the controls. Muscle pain during palpation was recorded in 53.3%, clicking in 53.3%, crepitation in 21.7%, reduced movement capacity of the TMJ in 41.7%, and restricted mouth opening in 31.7% of the RA patients examined. In the control group the most common symptoms and signs were clicking (57.5%), muscle pain during palpation (57.5%) and restricted opening (25.0%). Normal radiographic appearance of the TMJ in RA patients was found in 31.7%. Minor changes comprised 31.7%, moderate changes 21.6%, and severe changes or total loss of the condyle 15.0%. In the control group a normal joint was detected in 87.5%, while minor changes were encountered in 7.5%, and moderate or severe changes only in 5.0%. No relationship was found between Helkimo's anamnestic, clinical or occlusal indices and the severity of the disease graded according the criteria outlined by the American Rheumatism association (ARA). In the ARA group the frequency of signs and symptoms of dysfunction increased with the destructive changes in the TMJ area. In the controls, muscle pain during palpation and clicking sounds in the TMJ were most commonly connected with normal radiographic appearance of the TMJ. In the discriminant analysis the most discriminating factors were crepitation, tenderness to palpation of muscles and movement of TMJ.     

Rheumatoid arthritis and disk derangement of the temporomandibular joint. A comparative arthroscopic study.

Consecutive patients with clinical diagnoses of disk derangement and rheumatoid arthritis with temporomandibular joint (TMJ) signs and symptoms were compared by clinical, radiographic, and arthroscopic examination. Synovial biopsies were obtained from patients with arthroscopic features of synovial inflammation. No clinical sign or symptom was found to be specific of rheumatoid involvement although joint crepitation was most frequently found in rheumatic patients (p less than 0.001). Tomographic features of subchondral bone involvement were more frequently revealed in TMJs of rheumatic patients (p less than 0.001). At arthroscopy rheumatic patients often showed pronounced arthrotic changes and inflammation. In contrast to patients with disk derangement, fibrosis of the TMJ was frequent (p less than 0.001). Histologic examination of obtained synovial specimens correlated well with arthroscopic findings, and more pronounced inflammation was present in specimens from rheumatic patients.     

Long-term follow-up of intra-articular injections into the temporomandibular joint in patients with rheumatoid arthritis

A long-term (12 years) follow-up of treatment with intra-articular injections into the temporomandibular joint (TMJ) of steroid or non-steroid agents was performed in 21 patients with rheumatoid arthritis (RA) and symptomatic TMJs. The aim of the study was to compare symptoms, signs and radiological appearance of the TMJ initially and at the follow-up in this group of patients. Eleven patients were assigned to a steroid group and 10 patients to a non-steroid group. Initial and follow-up clinical and radiological examination procedures were the same. The radiological evaluation was based on a grading system using standard reference films. At follow-up, 14 patients reported no pain from the TMJ and positive changes in most clinical variables were found in both groups. Radiographic follow-up examination was performed on 12 patients. Initially, all but 4 of the 24 joints had structural bone changes. At follow-up, 2 joints had lower, 11 joints had unchanged and 11 joints had higher radiological grades. Two out of 5 and 3 out of 10 joints in the steroid and non-steroid group, respectively, showed progression of structural bone changes. Among 9 untreated joints, 6 had higher radiological grades and 3 were unchanged. In the 11 TMJs with higher radiological grades at follow-up, there was in most cases moderate progression of erosive changes. The results suggest that the long-term development of symptoms and signs from the TMJ in patients previously treated was good and the long-term progression of joint destruction was low for both steroid and non-steroid agents in this patient group with RA.     

Radiographic signs in the temporomandibular and hand joints in patients with psoriatic arthritis

The temporomandibular (TMJ) and hand joints of 64 patients with psoriatic arthritis (PA) were examined radiographically with panoramic tomography and dorsovolar projection. The associations between radiographic signs in the condyle of the TMJ and finger joints were analyzed with Pearson's product-moment correlation coefficient. Twenty-six patients (41%) had radiographic signs in their TMJs. Arthritic signs were seen in 14 (22%) and degenerative signs in 12 (19%) patients. Fifty-five patients (86%) had radiographic signs in their hands; 33 patients (52%) had arthritic and 22 (34%) degenerative signs. In the TMJ statistically significant correlations were found among erosion, flattening, and cortical sclerosis and also between osteophyte and cortical sclerosis. In the finger joints erosion correlated significantly with dislocation and loss of space. Erosion in the condyle of the TMJ was the only sign that correlated with changes in the finger joints such as erosion, dislocation, and ankylosis. Erosion in the TMJ also correlated with erosion in the metacarpophalangeal joint and wrist.     

Changes of the elastic fibre network of the rabbit temporomandibular joint following discectomy

Elastic fibres are thought to be very important for the function of various organs including the temporomandibular joint (TMJ). The current study was designed to examine changes in the elastic fibres of the TMJ following discectomy. The TMJs of six rabbits were surgically exposed, and the disc removed with a scalpel. Three untreated and three sham-operated rabbits were used as controls. Complete TMJs were removed in three rabbits 1 month and in three rabbits 3 months after discectomy and processed for histochemical demonstration of elastic fibres. In the TMJ 1 month after discectomy, osteoarthritic changes and a significant increase in the numbers of elastic fibres were observed in the condyle and articular eminence. In the TMJs 3 months after discectomy, they tended to revert to the levels in the condyle and articular eminence of the control TMJs. Our results show that after experimental discectomy, elastic fibres very often appear initially in the condyle and articular eminence, but they are destined to disappear later. This information may improve our understanding of the consequences of removal of the disc in clinical practice.     

MR evidence of temporomandibular joint fluid and condyle marrow alterations: occurrence in asymptomatic volunteers and symptomatic patients

The purpose of this study was to estimate the frequency and amount of temporomandibular joint (TMJ) fluid, as well as the frequency and type of condyle marrow alterations in asymptomatic volunteers and compare to patients with TMJ pain and dysfunction. Proton-density and T2 weighted magnetic resonance (MR) images of the TMJs of 62 asymptomatic volunteers and 58 symptomatic patients were analysed for fluid and condyle marrow alterations as well as disk position. The amount of fluid (increased T2 signal) was characterized as none, minimal, moderate or marked and related to the disk position. The differentiation between moderate and marked fluid was based on the maximum amount of fluid seen in the volunteers; more than this amount was categorized as marked fluid. The marrow of the mandibular condyle was categorized as normal, edema (increased T2 signal) or sclerosis (decreased proton-density and T2 signal) and related to fluid and disk position. In the 62 asymptomatic volunteers, 50 (81%) had none or minimal and 12 (19%) had moderate TMJ fluid. In the 58 symptomatic patients, 40 (69%) had none or minimal and 18 (31%) had moderate or marked fluid. Both in volunteers and patients, moderate fluid could be seen in joints with normal disk position, but was significantly associated with disk displacement. In the 62 volunteers, no signal abnormalities in the condyle marrow were found. In the 58 patients, six (10%) had abnormal bone marrow. These six patients had disk displacement and two had moderate or marked fluid. Marked fluid and condyle marrow abnormalities were therefore not encountered in any of the asymptomatic volunteers but in about 10% of the patients.     

The evaluation of temporomandibular joint disc position in TMJ disorders using MRI

The purpose of this study was to correlate disc position and the type of disc displacement, intra-capsular effusion and degenerative changes of the condyle as demonstrated in MRI studies. In this study, 126 temporomandibular joints (TMJs) of 63 patients with TMJ disorders were investigated using clinical examination and MRI. One hundred and twelve TMJs were found to have internal derangement as disc displacement. The angle between the posterior margin of the disc and the vertical line drawn through the centre of the condyle was measured on MRI for each TMJ. The positions of the discs were normal, 0 degrees-10 degrees, in 11.11%; slightly displaced, 11 degrees-30 degrees, in 37.30%; mildly displaced 31 degrees-50 degrees, in 15.08%; moderately displaced, 51 degrees-80 degrees, in 7.14% of the TMJs with anterior displacement with reduction (ADDR). The disc position was severely displaced anteriorly, as over 80 degrees, in all TMJs with anterior disc displacement without reduction (ADD), constituting 27.78% of all cases. We found that the smaller the degree of disc displacement the milder the internal derangement and that the intra-capsular effusion was more frequently associated with TMJ with ADDR. The degenerative condylar changes were more severe with an increased degree of anterior disc displacement.     

颞颌关节间接性损伤后不同时期X线表现及其意义

目的：研究山羊颞颌关节（TMJ）间接性损伤后关节结构的变化。方法：用自制撞击装置造成山羊双侧颞颌关节间接性损伤,分别于伤后2h、7d、1月、3月行X线断层摄影后处死材料,并进行组织学观察,正常关节作为对照。结果：X线断层摄片发现,TMJ损伤后关节腔模糊,腔隙缩小,髁突表面不平,结构不清,其位置由颞下凹正中逐渐偏向后。组织学观察发现,伤后早期1月内关节组织分别出现关节凹髁突表面纤维软骨破坏,关节盘纤维组织挫裂,关节腔内出现血肿等;晚期3月出现髁突表面软骨组织破坏、吸收,关节盘严重扭曲、变形。结论：一定程度的TMJ损伤可以导致TMJ内紊乱和TMJ骨关节病等后遗症的发生。X线断层摄技术是一种较好的动态观测TMJ结构和形态变化的方法。     

Effects of splint therapy in TMJ dysfunction: A study using magnetic resonance imaging

This pilot study was undertaken to correlate clinical and MRI diagnoses in seven symptomatic TMJ dysfunction patients and to account, if possible, for the clinical improvement in the signs and symptoms after the use of a maxillary stabilizing splint. The symptomatic TMJs were evaluated by means of MRI prior to splint insertion. Sagittal open/closed, and coronal closed images were obtained with a 0.3 T Fonar MR Scanner. A follow-up MRI was taken after three months of splint therapy for the purposes of a comparative study.
All subjects responded positively even at the early phase of splint treatment. By the end of the three month period, six subjects experienced full remission of pain in the TMJ and associated masticatory muscles with one subject experiencing only partial remission following therapy. Baseline MRI study revealed that only three subjects had anterior disc displacement while the other four subjects had normal disc/condyle relationships and morphology. In the follow-up MRI study, there were no signs of recapture of the three anteriorly displaced discs despite there being evidence of improved jaw movement and remission of pain symptoms.
The use of MRI in this preliminary study indicates that some but not all TMJ pain dysfunction syndromes are caused by internal derangements of the joint. A larger MRI study using the same clinical parameters is indicated for future research.     

In vivo morphometric analysis of inflammatory condylar changes in rat temporomandibular joint

Oral Diseases (2011) 17 , 499–507 Objective: Injection of complete Freund’s adjuvant (CFA) into the temporomandibular joint (TMJ) causes acute swelling around the joint and subsequent morphological alterations in the condyle. We aimed to evaluate changes in the three‐dimensional architecture of the condyle induced with CFA. Materials and methods: The CFA was injected into the unilateral TMJ of rats and morphological changes in the condyle were assessed repeatedly for 14 days by in vivo micro‐CT. Results: Osseous abnormalities of condyle were first observed at 3–5 days after CFA injection on the tomographic images, and the condylar deformation became more obvious thereafter. Among 12 condyles examined at 14 days postinjection, osteophytosis was observed in all of the specimens and bone erosion coexisted in five condyles. None of the saline‐treated condyles showed architectural changes. Significant changes were detected in the mesiolateral and rostrocaudal widths of the CFA‐treated condyles at 10–14 days postinjection (P < 0.01). The extent of both condylar bone formation and resorption was greater in the CFA‐injected TMJs than in saline‐injected TMJs (P < 0.05). Conclusion: These results indicate that CFA causes dynamic morphological changes in the condyle and that our experimental approach will provide new insights into the subacute inflammatory processes in the TMJ.     

He创伤致家兔颞下颌关节滑膜和软骨超微结构的改变

研究Ｈｅ创伤对家兔颞下颌关节滑膜和软骨的影响。方法 采用实验性Ｈｅ创伤动物模型，透射电镜下观察Ｈｅ创伤后颞下颌关节滑膜和软骨的超微结构特征。结果 髁突软骨表层结构破损，软骨层不同程度的软骨细胞变性，坏死。滑膜内膜层细胞变性，胞质内可见大量的空泡和近胞膜处的小泡，微丝增多，密集；细胞膜上可见微绒毛突起；     

Association between condylar morphology and changes in bony microstructure and sub‐synovial inflammation in experimental temporomandibular joint arthritis

J Oral Pathol Med (2011) 40 : 111–120 Background: In juvenile idiopathic arthritis involvement of the temporomandibular joints (TMJs) is often associated with mandibular growth deviations. The relation between the growth deviations and severity of the inflammation, condylar shape, the micro‐architecture, and the quality of the bone has not previously been investigated. This paper studies the effect on the bony structures in mandibular condylar development in rabbits with antigen‐induced arthritis. Methods: Included were 42 juvenile rabbits with ovalbumin‐induced arthritis of the TMJs treated with intraarticular saline, intraarticular etanercept or subcutaneous etanercept. A TMJ from each animal was scanned using micro‐computed tomography and structural parameters were calculated. Three‐dimensional reconstructions of the mandibular condyle were scored blindly as normal or abnormal. TMJs were stratified for condylar morphology and were evaluated against data on trabecular structural parameters, inflammation, degree of mineralization, overall mandibular growth, and mineral apposition rate. Results: Abnormal morphology were seen in 15/32 animals available for data analysis. Erosions were an uncommon finding. Abnormal morphology was strongly related to the degree of inflammation. The trabecular separation was larger in group with abnormal morphology than in the group with normal morphology. Abnormal condylar morphology was not associated with overall mandibular growth. No differences were observed in mineral apposition rate. No differences in structural parameters were seen according to treatment modality. Conclusion: We showed that severe inflammation in the TMJs during mandibular development was associated with morphological changes in the mandibular condyle. These changes were predominantly seen at the macro‐morphological level and only very few differences were structural.     

Disc mobility and arthroscopic condition of the temporomandibular joint associated with long-term mandibular discontinuity.

PURPOSE: The present study aimed to explore disc mobility and arthroscopically diagnosed morphologic changes in the temporomandibular joint (TMJ) associated with long-term mandibular discontinuity. PATIENTS AND METHODS: Twelve patients (24 TMJs) who had undergone mandibulectomy including the unilateral condyle or segmental mandibulectomy without mandibular reconstruction, more than 8 months before this study were examined. The 24 TMJs were classified into 3 groups as follows: group 1, TMJs with a major mandibular fragment including the mandibular body (n = 11); group 2, TMJs with a mandibular ramus including the coronoid process (n = 5); and group 3, TMJs with only a condylar process, a mandibular ramus not including the coronoid process, or without a condyle (n = 8). Disc mobility was evaluated by magnetic resonance imaging, and arthroscopic observation of the superior joint compartment (SJC) was performed in all TMJs. The relationship between disc mobility and the arthroscopic findings was also studied. RESULTS: The frequency of immobile discs differed significantly among groups 1 (0%), 2 (40.0%), and 3 (100%). Arthroscopic findings were normal in all SJCs of group 1. Various types of fibrous adhesions were observed in 40.0% of group 2 and in 75.0% of group 3. The development of fibrous adhesions in the SJC was significantly related to the presence of an immobile disc. CONCLUSIONS: Long-term immobilization of the TMJ in a nonfunctional state seems to promote the development of fibrous adhesions in the SJC. Preservation of the mandibular fragment including the coronoid process, during mandibulectomy appears to contribute to postoperative TMJ mobility. To ensure recovery of a physiologic TMJ after mandibulectomy, it seems important to re-establish TMJ mobility by establishing mandibular continuity as soon as possible.     

Bone SPECT imaging of patients with internal derangement of temporomandibular joint before and after splint therapy

OBJECTIVE: Temporomandibular joint (TMJ) patients with disc displacement without reduction have a misaligned disc-condyle structural relation. As the condition becomes chronic, painful osteoarthritic changes may occur. For these patients, splint therapy may help to position the condyle to a more structurally compatible and functional position and to decrease the loading force of articular surfaces. The aim of this study was (1). to evaluate osseous reactions and pain relief in patients with disc displacement without reduction after splint therapy and (2). to use single photon emission tomography (SPECT) bone imaging to compare the results with the opposite joint of the patient. STUDY DESIGN: Twelve patients, who presented with pain involving the TMJ and limited mouth opening and were confirmed by soft tissue imaging as having disc displacement without reduction, were included in the study. Each patient underwent bone SPECT imaging, after which semiquantitative evaluation of transaxial images was conducted. The ratios of affected TMJ to nonaffected TMJ, affected TMJ to occipital bone, and nonaffected TMJ to occipital bone were calculated. After 6 months of splint therapy, bone SPECT examinations were repeated. RESULTS: Before splint therapy, the ratios of affected TMJ to nonaffected TMJ and of affected TMJ to occipital bone were found to be significantly higher than the ratios after splint therapy (P < 0.005). CONCLUSION: Six-month splint therapy has a positive effect on the osseous reaction and pain related to internal derangements of TMJs.     

The effect of surgical treatment of the temporomandibular joint: a survey of 70 patients

Most patients with temporomandibular disorders (TMD) can be successfully treated by conservative methods, but approximately 10-20 percent have persistent symptoms. The aim of this study was to evaluate the signs and symptoms of TMD in patients treated with open surgery of the TMJ. Seventy-two patients (13 men, 59 women, mean age 37 years, range 14-68 years) were evaluated during an eight-year period. Altogether 45 right TMJs and 39 left TMJs were treated, including both TMJs during the same operation in eight of the cases. The patients were evaluated at follow-up in 1997. The degree of TMD at follow-up was assessed using the anamnestic and clinical dysfunction Helkimo indices. Most of the patients reported at the follow-up that they were subjectively satisfied with the surgical treatment. The main clinical findings in the post surgical patients at follow-up were TMJ sounds and deviation of the mandible during opening. The tenderness in the masticatory muscles and TMJs on palpation was reduced significantly and the ranges of mandibular movement were improved for all the patients. The mean anamnestic and clinical indices decreased with a statistical significance from the shortest follow-up group (Group I) to the longest on group (Group IV) (p = 0.000). The conclusion of this study was that after open surgical treatment of the TMJ, the patients have significantly better functioning of the masticatory system and reduced signs and symptoms of TMD in the long term.     

The effect of interocclusal appliances on temporomandibular joints as assessed by 3D reconstruction of MRI scans

Magnetic resonance imaging (MRI) enables simultaneous visualization of hard and soft tissues. The aims of the present study were to computer generate three-dimensional (3D) images, reconstructed from MRI scans of normal temporomandibular joints (TMJ), to assess the relative positions of the disc, condyle and articular surface of the temporal bone and to study the effect of two mandibular group function interocclusal appliances (IOAs). Bilateral MRI scans of 2 mm slice thickness were generated for the TMJs of 12 asymptomatic subjects with the image acquisition coils orientated in a corrected oblique sagittal plane. MRI scans were generated for all subjects with 3 mm interincisal distance IOAs, while a subgroup (n = 4) was also scanned with a 5 mm interincisal IOA in situ. An average of 10 slices through each TMJ were generated for the closed mouth and IOA positions. Three-dimensional reconstruction was performed on a 486 IBM compatible computer using a suite of nine programs not commercially available. Three-dimensional images allowed visualization of composite images of joint relationships. Subjective assessment indicated that joint relations in 3D were more informative than multiple separate 2D MRI scans. With the 3 mm IOA in situ, the disc was positioned posteriorly and superiorly to the condyle in three of 12 cases. In four of 12 cases the condyle, and in two of 12 cases both the disc and condyle, were positioned anteriorly and inferiorly. With the 5 mm IOA changes in condyle/disc and condyle/fossa relationships were more variable. It was concluded that 3D images of TMJs enabled the assessment of the positional changes of the condyle/disc and condyle/fossa relationships as altered by IOAs. However, the role of IOAs on the internal arrangements within the TMJ remains variable and is deserving of further study.     

Changes of the collagen fibre arrangement of the rabbit temporomandibular joint following discectomy.

PURPOSE: The purpose of the present study is to examine changes in arrangement of collagen fibres of the temporomandibular joint (TMJ) following discectomy. MATERIAL AND METHODS: Twelve male Japanese white rabbits were used. The right TMJs of six rabbits were surgically exposed, and the disc removed with a scalpel. Three untreated and three sham-operated rabbits were used as controls. The TMJs were removed in three rabbits 1 month and in three other rabbits, 3 months after discectomy and processed for demonstration of collagen fibres. RESULTS: One month after discectomy, collagen fibres in the fibrous layers of condyle and articular eminence were of various sizes and were running in various directions. Collagen fibres in the cartilaginous layers were sparser in the study TMJs than in the control TMJs. Three months after discectomy, the direction of collagen fibres in the fibrous layers of the condyle and articular eminence became organized and were similar to that in the control TMJs. However, collagen fibres in the cartilaginous layers of the condyle remained sparser 3 months after discectomy than in the control TMJs. CONCLUSION: Experimental discectomy in the rabbit alters the distribution and density of collagen fibres in the TMJ. Thorough postoperative follow-up seems to be necessary after discectomy.     

L-单甲基-精氨酸对颞下颌关节骨关节病治疗作用的实验研究

目的　研究一氧化氮合酶抑制剂L 单甲基 精氨酸对山羊实验性颞下颌关节骨关节病的治疗作用及可能机制。方法　通过双侧颞下颌关节上腔内注射胶原酶建立骨关节病模型 ,从注射胶原酶第 4周起 ,在左侧关节上腔内每隔 3d注射 0 5 %L 单甲基 精氨酸 0 5ml,共 7次 ,右侧同期注射生理盐水 0 5ml。注射胶原酶后 1 2周处死所有动物 ,取双侧关节标本作组织学检查并根据改良Mankin骨关节病评价标准评分。结果　评分结果 :L 单甲基 精氨酸侧为 3 83 ,而对照侧为 6 33 ,两者比较差异有高度显著性 (P <0 0 1 )。结论　L 单甲基 精氨酸关节腔内注射对山羊实验性颞下颌关节骨关节病的发展有抑制作用 ,其作用机制可能与L 单甲基 精氨酸抑制一氧化氮合酶在关节局部产生过多的一氧化氮有关