A histologic evaluation of the accuracy of TMJ diagnostic arthroscopy

A critical review of Dr. Charles S. Greene's article titled "Managing the Care of Patients with Temporomandibular Disorders: a new Guideline for Care" and a revision of the American Association for Dental Research's 1996 policy statement on temporomandibular disorders, approved by the AADR Council in March 2010, published in the Journal of the American Dental Association September 2010

Dr. Charles Greene's article, "Managing the Care of Patients with TMDs A New Guideline for Care," and the American Association for Dental Research's (AADR) 2010 Policy Statement on Temporomandibular Disorders, published in the Journal of the American Dental Association (JADA) September 2010, are reviewed in detail. The concept that all temporomandibular disorders (TMDs) should be lumped into one policy statement for care is inappropriate. TMDs are a collection of disorders that are treated differently, and the concept that TMDs must only be managed within a biopsychosocial model of care is inappropriate. TMDs are usually a musculoskeletal orthopedic disorder, as defined by the AADR. TMD orthopedic care that is peer-reviewed and evidence-based is available and appropriate for some TMDs. Organized dentistry, including the American Dental Association, and mainstream texts on TMDs, support the use of orthopedics in the treatment of some TMDs. TMDs are not psychological or social disorders. Informed consent requires that alternative care is discussed with patients. Standard of care is a legal concept that is usually decided by a court of law and not decided by a policy statement, position paper, guidelines or parameters of care handed down by professional organizations. The 2010 AADR Policy Statement on TMD is not the standard of care in the United States. Whether a patient needs care for a TMD is not decided by a diagnostic test, but by whether the patient has significant pain, dysfunction and/or a negative change in quality of life from a TMD and they want care. Some TMDs need timely invasive and irreversible care.

The levels of vascular endothelial growth factor in the synovial fluid correlated with the severity of arthroscopically observed synovitis and clinical outcome after temporomandibular joint irrigation in patients with chronic closed lock

OBJECTIVE

This study aimed to investigate the level of vascular endothelial growth factor (VEGF) in the temporomandibular joint (TMJ) synovial fluid (SF) and the severity of arthroscopically observed synovitis before and after visually guided TMJ irrigation (VGIR) in patients with chronic closed lock (CCL). In addition, the findings were correlated with the clinical outcome.

STUDY DESIGN

Twenty-four patients with unilateral CCL, who underwent a second VGIR either as a repeated therapeutic TMJ irrigation or as a follow-up arthroscopy, were enrolled in the study. They were divided into either successful (s-group; n = 11) and unsuccessful (u-group; n = 13) groups. The VEGF level in the aspirated SF and the severity of synovitis were compared between the s- and u-groups. In each group, the same parameters were compared before and after VGIR. The correlation of the VEGF level with the severity of synovitis was also studied.

RESULTS

At the first VGIR, the VEGF levels showed no significant differences when comparing s- and u-groups. At the second VGIR, the VEGF level was significantly higher in the u-group. The VEGF level significantly decreased after the first VGIR in the s-group but remained unchanged in the u-group. There was no significant correlation between the VEGF level and the severity of synovitis.

CONCLUSIONS

The level of VEGF in TMJ SF seems to reflect the clinical status in patients with CCL. Moreover, VEGF may be an important target molecule in future chemotherapy of TMJ CCL.

TRAIL, DR5 and caspase 3-dependent apoptosis in vessels of diseased human temporomandibular joint disc. An immunohistochemical study

To evaluate the apoptosis involvement in the angiogenesis as a self-limiting process in patients with temporomandibular joint (TMJ) degenerated disc vessels, we assessed, by immunohistochemistry, the detection of TRAIL, its death receptor DR5 and caspase 3. TRAIL, its death receptor DR5 and caspase 3 expression were studied by immunohistochemistry in 15 TMJ discs displaced without reduction and in 4 unaffected discs. These apoptosis molecules were detected in the intima and media layers of newly formed vessels affected discs. In conclusion, vessels apoptosis activation in TMJ disc with ID could be regarded as a self-limiting process that try to leads to vessel regression; in this way an inhibition of angiogenic vessels may prove a key strategy in limiting pathological angiogenesis, by cutting off blood supply to tumors, or by reducing harmful inflammation.

Assessment of synovial vascularization by power Doppler ultrasonography in TMJ internal derangements treated arthroscopically

Our aim was to evaluate the effect of arthroscopic lysis and lavage of the temporomandibular joint (TMJ) on synovial microvascularisation by comparing preoperative and postoperative grades measured by power Doppler ultrasonography (US). We studied 22 patients with hypomobility, clicking, and pain in the TMJ. Power Doppler US were obtained preoperatively to assess the presence of synovial microvascularisation, and arthroscopic lysis and lavage were done after conservative treatment had proved unsuccessful. The severity of synovitis was assessed arthroscopically. The postoperative power Doppler US scans were obtained 2 months later. Other arthroscopic variables were roofing, adhesions, chondromalacia, clicking, and pain. Arthroscopic synovitis with varying degrees of synovial vascularisation was detected in all patients. Pain scores decreased considerably during the postoperative period. We conclude that power Doppler US is a good technique for the assessment of synovial changes by microvascularisation. Arthroscopy of the TMJ reduces synovial vascularisation.

Histologic and histomorphometric analysis of posterior region of the human temporomandibular disc

OBJECTIVE

The aim of this study was to analyze histologic and histomorphometric features of the articular disc in groups with and without disc displacement.

STUDY DESIGN

A sample of 39 temporomandibular joints TMJs (31 case specimens, 8 control specimens) from 28 patients (mean age 31.2 years) were recruited for this study. The patients were considered to be affected and treated surgically with disc repositioning when presenting painful clinical signs of disc displacement after unsuccessful nonsurgical treatment for at least 6 months. Of the control patients, 4 presented condyle fracture which required opening to be reduced for treatment, and 4 displayed active condyle hyperplasia. The posterior region of the disc was removed and sent for histologic and histomorphometric analysis. Histologic (hematoxylin-eosin) and histomorphometric (picro-Sirius red) analyses were performed. Statistically significant differences between the analyzed groups were accessed through the chi-squared test (P <or= .05). The Mann-Whitney U test was used to observe the differences between mean values when variables did not present normal distribution [Kolmogorov-Smirnov(a) test].

RESULTS

There were no significant differences between the groups in relation to the parameters studied by histologic and histomorphometric analysis (using or not using polarization).

CONCLUSIONS

To the limits of this study, there were no significant histologic and histomorphometric differences in the articular disc between groups with and without TMJ dysfunction.

Expression of interleukin 8 in synovial tissues in patients with internal derangement of the temporomandibular joint and its relationship with clinical variables

OBJECTIVES

The objectives of this study were to assay interleukin 8 (IL-8) in synovial tissues of the temporomandibular joint (TMJ) with symptomatic internal derangement, and to assess its relationship with clinical variables.

STUDY DESIGN

Forty-six joints in 44 patients were examined using an immunohistochemical technique. As controls, 8 joints in 7 subjects with habitual dislocation without pain were also examined.

RESULTS

IL-8 was expressed mainly in the blood vessels beneath the lining cells in 37 of the 46 joints (80%) with internal derangement and in 2 of the 8 control joints. The percentage of IL-8-positive cells was significantly higher in the internal derangement group than in the control group (P = .004). The percentage of IL-8-positive cells showed no correlation with joint pain or number of infiltrating cells.

CONCLUSIONS

IL-8 was up-regulated in inflamed synovial tissues in patients with internal derangement. Because IL-8 has no significant correlation with clinical variables, IL-8 may play a secondary role in the pathogenesis of the internal derangement of the TMJ.

The role of facial trauma as a possible etiologic factor in temporomandibular joint disorder

PURPOSE

Facial trauma has been suggested as a possible etiologic factor of temporomandibular joint disorder. However, there is little information on the role of macrotrauma. The main purpose of this study was to validate facial trauma as a potential etiologic factor for temporomandibular joint (TMJ) disorder. Multidirectional approaches were applied for the evaluation of the changes of TMJ after TMJ macrotrauma.

PATIENTS AND METHODS

Analysis of TMJ status including arthroscopic examination, histomorphologic examination, and synovial fluid biochemical analysis were performed on the patients with mandibular fractures. Additionally, the efficacy of arthrocentesis for the patients of mandibular fracture was evaluated from the functional point of view.

RESULTS

In arthroscopic examinations, evidence of synovitis with variable degrees was found. The representative findings are fibrillation and ecchymosis. On histomorphologic examination, bloody smear, degenerated cells and cartilage, inflammatory cells, and crystal were observed. In biochemical analysis, considerable amounts of prostaglandin E(2) and leukotriene B(4) were detected in the synovial fluid of the patients.

CONCLUSION

The inflammatory and degenerative changes of TMJ can develop after facial trauma. Trauma can be a possible etiologic factor in cartilage degeneration, and biochemical and intra-articular pathology. Clinicians should recognize the etiologic importance of macrotrauma, and long-term evaluation of the TMJ as well as adequate treatment is required for patients with facial trauma.

Expression of capsaicin receptor TRPV-1 in synovial tissues of patients with symptomatic internal derangement of the temporomandibular joint and joint pain

OBJECTIVE

To elucidate expression of capsaicin receptor TRPV-1 in synovial tissues of the human temporomandibular joint (TMJ) with internal derangement and discuss its relationship with joint pain.

STUDY DESIGN

Fifty-four TMJs in 54 patients were examined using an immunohistochemical technique. As controls, 10 TMJs with habitual dislocation without pain were also examined.

RESULTS

TRPV-1 was expressed mainly in the blood vessels beneath the lining cells in synovial tissues from 31 of the 54 joints with internal derangement and from 8 of the 10 control joints. The extent score of TRPV-1-stained cells with internal derangement was not significantly higher than that of controls. The extent score of TRPV-1 showed no correlation with joint pain.

CONCLUSIONS

TRPV-1 was detected in the region of the posterior disk attachment of synovial tissues from the TMJ in patients with internal derangement and controls. TRPV-1 may play a role in maintenance of the physiologic condition of the TMJ.

Vascular endothelial growth factor concentrations in synovial fluids of patients with symptomatic internal derangement of the temporomandibular joint

BACKGROUND

Vascular endothelial growth factor (VEGF) is an inducer of angiogenesis and permeability of small blood vessels. We determined the concentrations of VEGF in synovial fluid of patients with symptomatic internal derangement of the temporomandibular joint (TMJ).

METHODS

Diluted synovial fluid was collected by a pumping procedure from 22 TMJs of patients with internal derangement and 10 control TMJs. VEGF concentration was determined by an enzyme-linked immunosorbent assay.

RESULTS

The VEGF was detected in 14 of the 22 joints (64%) of patients with internal derangement, at a mean concentration of 67 pg/ml, but in only one control joint (12.5 pg/ml) (P = 0.004 for the difference in concentration). There was a significant correlation between VEGF concentration and total protein concentration in the synovial fluid (P = 0.002).

CONCLUSIONS

The increased concentration of VEGF in patients with symptomatic internal derangement suggests that this growth factor may be involved in the pathogenesis of this condition.

Levels of fibroblast growth factor 2 in synovial fluids in human patients with internal derangement of the temporomandibular joint

OBJECTIVE

We sought to elucidate the levels of fibroblast growth factor 2 (FGF-2) in synovial fluid taken from internally deranged human temporomandibular joints (TMJs) and to discuss the role of FGF-2 in the pathogenesis of internal derangement.

STUDY DESIGN

Through the use of a pumping procedure, diluted synovial fluid was collected from the upper joint compartment of 22 TMJs with evidence of internal derangement (21 patients) and 8 TMJs with no such evidence (5 control subjects). Two of the control subjects were patients who had habitual dislocation, and three were healthy volunteers. The level of FGF-2 in the synovial fluid was assessed by means of an enzyme-linked immunosorbent assay.

RESULTS

FGF-2 levels were at detectable levels in 15 of the 22 TMJs (68%) with internal derangement. The mean concentration of FGF-2 was 24 pg/mL. In the control group, FGF-2 levels were detectable in only 1 of 8 joints (13%), for a concentration of 3 pg/mL. The mean concentration of FGF-2 in the synovial fluid was significantly higher in the internal derangement group than in the control group (P =.02).

CONCLUSIONS

FGF-2 levels are elevated in the human synovial fluid of TMJs with internal derangement.

Expression of osteoprotegerin in synovial tissue and degradation of articular cartilage: comparison with arthroscopic findings of temporomandibular joint disorders

OBJECTIVE

The aim of this study was to investigate the correlations among the expression of osteoprotegerin (OPG) in synovial tissue and the degree of synovitis, the degeneration of articular cartilage, and the adhesions in patients with internal derangement and osteoarthritis of the temporomandibular joint (TMJ). Study design The expression of OPG, which was detected immunohistochemically, and the degree of arthroscopy of 31 patients with internal derangement and osteoarthritis of the TMJ were assessed and the correlations between them were analyzed statistically.

RESULTS

OPG was expressed in the cytoplasm of the endothelial cells, synovial lining cells, and fibroblast cells. TMJs with osteoarthritis had a higher degree of articular cartilage degeneration than did TMJs with internal derangement. There was a correlation between the expression of OPG in the endothelial cells and the degree of the articular cartilage degeneration (P <.01).

CONCLUSION

The expression of OPG might be associated with the development of degenerative changes of articular cartilage.

Does joint effusion on T2 magnetic resonance images reflect synovitis? Part 3. Comparison of histologic findings of arthroscopically obtained synovium in internal derangements of the temporomandibular joint

OBJECTIVES

To evaluate the relationship between the volume of joint effusion (JE), determined by T2-weighted magnetic resonance imaging (MRI), and microscopic findings of synovial inflammation in internal derangement of the temporomandibular joint (TMJ).

STUDY DESIGN

Magnetic resonance images of 53 symptomatic TMJs (53 patients) associated with painful hypomobility were taken to evaluate the degree of JE on a scale of 0 to 3. Within 2 months after MRI, biopsy specimens obtained by arthroscopy were quantitatively assessed, on the basis of Gynther's grading system, for severity of hyperplasia of synovial lining cell layers, vascularity, and the presence of inflammatory cells. Each synovitis score was compared among the 4 JE grades, as well as between 2 groups-effusion present (grades 2 and 3) and effusion absent (grades 0 and 1)-by using the Spearman correlation coefficiency and the Mann-Whitney U test.

RESULTS

The distribution of JE was as follows: 14 joints had grade 0, 9 joints had grade 1, 19 joints had grade 2, and 11 joints had grade 3. Significant relationships were found between the grades of JE and scores of synovial lining cell layers (P =.0012) as well as between the grades of JE and scores of presence of inflammatory cells (P =.0064). The joints with effusion had significantly higher scores for synovial lining cell layers (2.0 +/- 0.2) than the joints without effusion (1.3 +/- 0.2) (P =.029). There was no statistically significant correlation between the scores of vascularity and JE (P =.394).

CONCLUSIONS

The evidence of JE on MRI might correlate with synovial inflammatory activity. It confirms the common consensus that JE probably reflects synovitis, especially when synovial hyperplasia has a key role in the pathogenesis of JE.

Correlations of the expression of fibroblast growth factor-2, vascular endothelial growth factor, and their receptors with angiogenesis in synovial tissues from patients with internal derangement of the temporomandibular joint

Synovitis in internal derangement of the temporomandibular joint (TMJ) is accompanied by the growth of new blood vessels. Fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF) are well-characterized angiogenic factors. The objective of this study was to elucidate the correlation between the expression of FGF-2, VEGF, and their receptors-FGF receptor-1 (FGFR-1) and VEGF receptor-1 (Flt-1)-with microvessel density in synovial tissues of the TMJ. Using an immunohistochemical technique, we examined 47 joints (45 patients) with internal derangement. Individual microvessel density was evaluated by means of the CD34 antibody, a specific endothelial marker. The correlation between the percentage of immuno-positive cells and microvessel density was evaluated. In multiple logistic regression analysis, the correlation between the percentage of Flt-1-positive cells and microvessel density was significant [p = 0.005, odds ratio = 1.071, 95% confidence interval = 1.021-1.124]. These results suggest that the expression of the VEGF/Flt-1 system is involved in angiogenesis in inflamed synovial tissue in the TMJ.

Relation between the expression of vascular endothelial growth factor in synovial tissues and the extent of joint effusion seen on magnetic resonance imaging in patients with internal derangement of the temporomandibular joint

The aim of this study is to elucidate the relation between the expression of vascular endothelial growth factor (VEGF) in synovial tissues and the extent of joint effusion seen on magnetic resonance imaging (MRI) in patients with internal derangement of the temporomandibular joint (TMJ). Using an immunohistochemical technique, we examined specimens of synovial tissues from 41 joints in 40 patients with internal derangement. Specimens from 36 of the 41 joints stained for VEGF. There was a significant correlation between the percentage of the VEGF-stained cells and the grade of joint effusion seen on MRI (P=0.0002, r=0.62). The correlation between the two was also significant on multiple logistic regression analysis (P=0.003, odds ratio=1.75). These results suggest that VEGF may have an important role in the genesis of joint effusion.

Correlation between the arthroscopic diagnosis of synovitis and microvessel density in synovial tissues in patients with internal derangement of the temporomandibular joint

OBJECTIVE

To elucidate the correlation between the arthroscopic diagnosis of synovitis and microvessel density in synovial tissues in patients with internal derangement of the temporomandibular joint (TMJ).

STUDY DESIGN

Forty-three joints in 41 patients with internal derangement were examined and biopsies taken. Microvessel density was evaluated using the immunohistochemical method for CD 34 antibody. Arthroscopically diagnosed synovitis was evaluated according to Murakami's criteria.

RESULTS

In patients with internal derangement, arthroscopically diagnosed synovitis scores averaged 5.2+/-2.0, according to Murakami et al. (1991). Small to large blood vessels were observed clearly with CD 34 stain. The mean microvessel density was 22.7+/-15.6 per two high power fields (magnification x200). Synovitis scores correlated significantly with microvessel density (p=0.002, r=0.43).

CONCLUSION

Synovitis evaluated using Murakami's scores correlated well with the number of blood vessels in synovial tissues in patients with internal derangement of the TMJ. This demonstrates that synovitis is linked to inflammation-related blood vessel density of the synovial tissues.

Ultrastructural study of synovitis induced by trauma to the rat temporomandibular joint (TMJ)

BACKGROUND

Electron microscopy was used to examine the histologic effect of trauma on the rat temporomandibular joint synovial membrane.

METHODS

Trauma to the TMJ in male Wister rats (100-200 g) was introduced through repeated forced condylar hypermobility. Ultrastructural observations were made 5 days and 6 weeks after the trauma.

RESULTS

The early response of the synovial membrane was synovial hyperplasia, type A synovial cell loss, dilation of the r-ER in the type B synovial cells and fibrin deposition on the synovial surfaces. The late response included degeneration of synovial cells with swollen mitochondria and cell projections, and cell fragmentation. Large amount of fibrin deposition on opposing surface layers was also noticed.

CONCLUSION

The type A cell loss and fibrin deposition followed by the occurrence of fibrinous materials at opposing surface layers of the synovial membrane suggest that traumatic synovitis causes synovial adhesions.

Characterization of tissue components in the temporomandibular joint disc and posterior disc attachment region: internal derangement and control autopsy specimens compared by morphometry

PURPOSE

Our aim was to morphologically investigate the occurrence of fibroblasts, chondrocytes, and blood vessels in the tissue of the temporomandibular joint (TMJ) disc, the intermediate zone, and the posterior disc attachment region in control autopsy specimens and to compare the results with those observed in corresponding tissues from patients with TMJ internal derangement.

PATIENTS AND METHODS

First, 20 bilateral TMJ disc specimens from selected autopsy cases were analyzed by conventional morphometry. Thus, the volume density of fibroblasts, chondrocytes, and blood vessels was determined. Second, the obtained results from the right joint of the autopsy disc specimens were compared with 12 TMJ disc specimens obtained at surgery from patients with internal derangement.

RESULTS

The tissue compartments of interest (disc, intermediate zone, and posterior disc attachment region) were identified unequivocally in all specimens. None of the autopsy cases showed any significant difference between the right and left joints or related to gender. The only variable that differed between autopsy and patient specimens was volume density of blood vessels, which was higher in patient specimens.

CONCLUSIONS

We found that the volume density of blood vessels was significantly higher in the posterior disc attachment region in patient specimens than in autopsy controls. Whether this reflects a role for vessels in the pathogenesis of TMJ internal derangement or merely is a reaction to another type of injury remains to be settled. In both the autopsy control and patient specimens, chondrocytes and fibroblasts were characteristic for disc respective posterior disc attachment region. Thus it appears that the occurrence of these cells can be used to distinguish TMJ disc from posterior disc attachment in small biopsy specimens.

Relationships between pain-related mediators and both synovitis and joint pain in patients with internal derangements and osteoarthritis of the temporomandibular joint

OBJECTIVE

The purpose of this study was to investigate the correlations between the concentrations of pain-related mediators in synovial fluid and the degree of synovitis and between the concentrations of pain-related mediators and the degree of joint pain in patients with internal derangement and osteoarthritis of the temporomandibular joint.

STUDY DESIGN

The concentrations of substance P, serotonin, bradykinin, leukotriene B(4) (LTB(4)), and prostaglandin E(2) in SF and the degree of arthroscopic synovitis of 32 joints with internal derangement and osteoarthritis were assessed. The correlations between the concentration of each mediator and the score of arthroscopic synovitis and between the concentration of each mediator and the score of joint pain were analyzed statistically.

RESULTS

The detection rates of substance P, serotonin, bradykinin, LTB(4), and prostaglandin E(2) were 25%, 25%, 91%, 53%, and 16%, respectively. Positive correlations were found between the concentrations of bradykinin and LTB(4) and the score of synovitis.

CONCLUSION

Bradykinin in SF might be useful as an index of the degree of synovitis.

Interleukin-1beta stimulates interleukin-8 production and gene expression in synovial cells from human temporomandibular joint

PURPOSE

The aims of the present study were to isolate and characterize cultured synovial cells from human temporomandibular joint (TMJ) specimens and to investigate the effect of interleukin (IL)-1beta on IL-8 production and gene expression in those cells.

MATERIALS AND METHODS

Synovial cells (HTS cells) were isolated from TMJ synovial tissues using an outgrowth method and then primary cultured. The cells were examined for cell-specific markers of fibroblast, macrophage, and dendritic cells using immunocytochemistry. HTS cells were then treated with IL-1beta, and amounts of IL-8 were measured by enzyme-linked immunosorbent assay. IL-8 production and expression were also investigated using immunocytochemistry and a reverse transcription-polymerase chain reaction method.

RESULTS

HTS cells were positive for the fibroblast-specific markers, such as vimentin and propyl 4-hydroxylase. The macrophage or dendritic cell markers and HLA class II antigen were negative. Furthermore, IL-1beta enhanced IL-8 production in HTS cells in a time- and dose-dependent manner and stimulated IL-8 gene expression.

CONCLUSIONS

HTS cells may provide important advantages for studies of the cellular and molecular mechanisms in the TMJ. In addition, we found that IL-1beta stimulated IL-8 production through an increase in IL-8 gene expression in HTS cells, which may be associated with the increase of infiltrating inflammatory cells seen in the synovial membrane of TMJ disorders.

The expression of vascular endothelial growth factor in synovial tissues in patients with internal derangement of the temporomandibular joint

OBJECTIVE

The aim of this study was to elucidate the expression and localization of vascular endothelial growth factor (VEGF) in synovial tissue taken from the temporomandibular joint (TMJ) with internal derangement (ID) and discuss the role of VEGF in the pathogenesis of ID.

STUDY DESIGN

Through the use of an immunohistochemical technique, 39 TMJs in 37 patients were examined. As controls, synovial tissue specimens from 6 joints in 6 patients with habitual dislocation were also examined.

RESULTS

In the synovial tissue from 35 of the patients with ID, expression of VEGF was observed in the synovial lining cells, in the endothelial cells of the blood vessels, and in the fibroblasts. In contrast, expression of VEGF was found in the TMJ tissue from only 2 of the controls. The percentage of VEGF-positive cells in the ID specimens was significantly higher than that in the habitual dislocation specimens (P < .02), and the expression of VEGF significantly correlated with the arthroscopic synovitis score (P = .004).

CONCLUSION

These results suggest that the expression of VEGF is upregulated and involved in the development of inflammatory changes in synovial tissues in TMJs with ID.

Proinflammatory cytokines and arthroscopic findings of patients with internal derangement and osteoarthritis of the temporomandibular joint

This study investigated the correlations between the concentrations of proinflammatory cytokines in synovial fluid and the degree of synovitis on the one hand, and the degree of degeneration of articular cartilage on the other hand, in patients with internal derangement and osteoarthritis of the temporomandibular joint. We measured the concentrations of interleukin-1beta (IL-1beta), tumour necrosis factor-alpha (TNF-alpha), IL-6 and IL-8 in synovial fluid and the degree of arthroscopic synovitis and degeneration of articular cartilage in 37 joints with internal derangement and osteoarthritis. The correlations between the concentration of each cytokine and the score of each arthroscopic feature were analysed statistically. The detection rates of IL-1beta,TNF-alpha, IL-6 and IL-8 were 57%, 78%, 89% and 70%, respectively. There was a positive correlation between the IL-6 concentration and the synovitis score (P = 0.02). Measurement of IL-6 in synovial fluid might be useful as an indicator of the extent of synovitis.

Accuracy of histologic grading of synovial inflammation in temporomandibular joints with internal derangement using Gynther's system

PURPOSE

The purpose of this study was to evaluate the accuracy of the system by Gynther et al (J Oral Maxillofac Surg 56:1281, 1998) for histologic grading of synovial inflammation in the temporomandibular joint (TMJ) in arthroscopically obtained synovial biopsy specimens.

PATIENT AND METHODS

Thirty-three human TMJ synovial biopsy specimens from patients with internal derangement of the TMJ were evaluated using the system of Gynther et al. The results were compared statistically with the intensity of synovitis seen arthroscopically using Spearman ranked correlation coefficient.

RESULTS

In 2 of the 3 parameters tested, a statistically significant correlation was found between the histologic findings by the system of Gynther et al and arthroscopic findings using the scale of Murakami et al (J Oral Maxillofac Surg 49:1159, 1991)

CONCLUSION

These results suggest that histologic grading of synovial inflammation by the system of Gynther et al has considerable accuracy. However, more investigations are necessary to confirm the results.

MR grading of temporomandibular joint fluid: association with disk displacement categories, condyle marrow abnormalities and pain

The purpose of this study was to investigate temporomandibular joint (TMJ) effusion on magnetic resonance (MR) images, and its association with specific categories of disk displacement, bone marrow abnormalities and pain. From a series of 523 consecutive TMJ MR imaging studies of patients referred to imaging because of pain and dysfunction, those with TMJ effusion, defined as an amount of fluid that exceeded the maximum amount seen in a control group of asymptomatic volunteers, were analysed. The selected patients were reassessed and the amount of TMJ fluid was graded bilaterally according to a set of reference films. Other parameters recorded included disk displacement categories and condyle marrow abnormalities. Pain self-records were obtained from the patients immediately before MR imaging. The association between the recorded parameters and TMJ pain was analysed with t-tests and regression analysis. Of the 523 patients, 70 (13%) had TMJ effusion, which was unilateral in 61%. Only 9% of the 70 patients had effusion bilaterally, whereas bilateral disk displacement was found in 80%. In the 76 joints with effusion, 83% showed two specific categories of disk displacement at closed mouth. Condyle marrow abnormalities were found in 31% of the 70 patients, mostly on one side, and in 24% of the 76 joints. An in-patient regression analysis of the side difference in TMJ pain showed that effusion and condyle marrow abnormalities were significant pain-increasing factors. In conclusion, patients with TMJ effusion represent a subgroup with pain and dysfunction with more severe intra-articular pathology than those with disk displacement but no other joint abnormalities.

The outcome of arthroscopic treatment of temporomandibular joint arthropathy

Ninety patients underwent arthroscopic temporomandibular joint surgery to 124 joints for arthropathy which had failed to respond to at least six months of non-surgical treatment. They were surveyed at between 6 months and 5 years (mean 2.5 years) after surgery and 63 per cent responded to the survey. They reported an 82 per cent improvement for pain (50 to 100 per cent better), 80 per cent for clicking and 82 per cent for locking. There was no morbidity following the treatment. Arthroscopic surgery should be considered for advanced temporomandibular joint arthropathy which is refractory to non-surgical treatment.

Arthroscopic findings in osteoarthritic temporomandibular joints

PURPOSE

This article reports on the results of a study of the arthroscopic findings in the joint surfaces of osteoarthritic temporomandibular joints (TMJs).

PATIENTS AND METHODS

Arthroscopy was performed in the upper joint compartment of 40 TMJs in 40 patients. Thirty-one TMJs that were diagnosed with osteoarthritis (OA) constituted the OA group. On the basis of the presence of symptoms related to disc displacement and perforation, OA subgroups were defined. Nine TMJs that were not involved with OA constituted the control group. During the examination, various arthroscopic variables were recorded. Differences between groups and between subgroups were tested statistically.

RESULTS

In the OA group, several arthroscopic variables were found significantly more frequently than in the control group. These included retrodiscal tissue redundancy, adhesions, and heightened attachment to the posterior wall of the glenoid fossa; articular disc displacement and limited mobility; and cartilage degeneration in the articular eminence. Moreover, in the OA group, disc displacement was found significantly more frequently in the period after 6 months than during the first 6 months of clinical signs and symptoms. Anterodiscal hypervascularity was found significantly more frequently during the first year than after the first year, as well as more during the first 2 years than after the first 2 years of clinical signs and symptoms, whereas a lowered attachment on the anterior slope of the articular eminence was found significantly more often after 2 years than during the first 2 years of clinical signs and symptoms.

CONCLUSIONS

The findings in this study suggest that OA of the TMJ may initially result in synovial tissue hypervascularity, creeping synovitis, and redundancy, and subsequently in adhesion formation and a reduction of the posterior and anterior recess. Because of cartilage fibrillation on the articular eminence, and the subsequently reduced surface smoothness, the articular disc may become displaced. Eventually, disc mobility is limited, and adhesions and a reduced posterior and anterior recess prevail.

Development and histologic characteristics of synovitis induced by trauma in the rat temporomandibular joint

Histopathological changes caused by trauma to the rat temporomandibular joint synovium were examined by light microscopy. The trauma was induced by forced hypermobility of the condyle. Pathological changes of the synovium were found primarily in the anterior pouch of the upper joint compartment. The main findings included surface cell proliferation, increased capillary hyperemia, fibrin deposits on the surfaces of inflamed synovial membranes, and fibrinous adhesion between closely opposed synovial membranes. A gradual change from fibrinous adhesion to fibrous adhesion was also seen.

Histologic study of synovitis induced by trauma to the rat temporomandibular joint

OBJECTIVE

The purpose of this study was to establish and histologically examine the time course of synovitis induced by trauma to the rat temporomandibular joint.

STUDY DESIGN

Synovitis of the temporomandibular joints of 8-week-old male Wister rats was induced by forced condylar hypermobility, which was administered 10 times successively once a day for 10 days. Pathologic changes were observed microscopically at 2 and 5 days and 2, 4, 6, 8, 10, and 20 weeks after treatment.

RESULTS

Histologic findings from the 5th day to the 6th week after treatment were characterized by multiple layers of synovial cells, an increase of dilated vasculature, fibrin deposits, and synovial adhesion. These findings were in good agreement with those reported for the human temporomandibular joint. The pathologic changes decreased with advancing time, and synovitis was not observed at 20 weeks after treatment.

CONCLUSION

The present procedure for inducing synovitis of the temporomandibular joint in rats will be useful in understanding the pathogenesis of synovitis in human temporomandibular joints.

Synovial inflammation in arthroscopically obtained biopsy specimens from the temporomandibular joint: a review of the literature and a proposed histologic grading system

Data indicate that the synovial lining of the temporomandibular joint (TMJ) in some respects differs from other joints. The normal variation in morphology of the synovial lining of the TMJ is quite great, whereas the variation in pattern of pathologic changes appears to be relatively small (ie, synovial inflammation is not of the severity as that in other joints). In the current review, a system for histologic grading of synovial inflammation is proposed. The system is based on semiquantitative evaluation of the following set of parameters: 1) synovial lining cell layers; 2) vascularity (number or size of vascular profiles); and 3) Inflammatory cell infiltrate (commonly lymphocytes).

Temporomandibular joint involvement in generalized osteoarthritis and rheumatoid arthritis: a clinical, arthroscopic, histologic, and immunohistochemical study

Twenty patients having generalized osteoarthritis (GOA) and symptomatic temporomandibular joints (TMJs) were compared with 22 patients having rheumatoid arthritis (RA) and TMJ symptoms, and also with an age-matched reference tissue material obtained at autopsy from 17 TMJs. Muscle tenderness was commoner in GOA. Arthroscopically, high frequencies of synovitis, degenerative changes, and fibrosis were observed in both groups, with more pronounced inflammatory and degenerative changes in RA patients, despite a shorter duration of TMJ symptoms. A correlation was noted between lateral joint tenderness and pronounced synovitis in RA patients. Histologic and immunohistochemical examinations added useful information to arthroscopy and showed similarly high frequencies of synovial inflammation in GOA and RA patients, differing clearly from those in the reference material. Connective-tissue degeneration was commoner in GOA patients. GOA and RA probably have different causes, but, interestingly, the tissue reaction was similar in the TMJs, although pronounced inflammatory and degenerative changes seemed to develop faster in RA.

Temporomandibular arthropathy: correlation between clinical signs and symptoms and arthroscopic findings

The clinical signs and symptoms of temporomandibular arthropathy were correlated with arthroscopic features of temporomandibular joint disease in 200 consecutive patients. The diagnostic accuracy of the selected clinical signs and symptoms was also tested with arthroscopy as the standard, and sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) were calculated. Pronounced osteoarthrosis was more frequently associated with joint crepitus (P < 0.001). Adhesions were more frequently associated with reduced maximum protrusion (P < 0.001). Crepitation was the only clinical sign that showed acceptable values for SE, SP, PPV, and NPV, and only in diagnosing advanced osteoarthrosis. The values for mild osteoarthrosis were low.

MRI evidence of high signal intensity and temporomandibular arthralgia and relating pain. Does the high signal correlate to the pain?

In order to investigate the relationship between various temporomandibular joint (TMJ) pain levels and the detection of high signal intensity (joint effusion) on T2 weighted magnetic resonance imaging (MRI), 19 consecutive patients who complained of unilateral painful TMJ hypomobility (closed locking) were involved in this study. All patients were clinically examined in a routine manner, and all patients rated their pain levels by a visual analogue scale and eight pain questionnaire prior MRI study. T1 and T2 weighted MRI was taken in sagittal section at unilateral affected joint side. The presence or absence of a high signal intensity spot within the TMJ compartment were judged by three examiners. The high signal intensity was detected in 10 joints, but not in 9 joints. In between these two groups, the pain ratio was calculated and compared. The data showed that there was no significant statistical correlation between pain levels and the presence of high signals. This study disclosed that the MRI detection of high signal intensity in the closed locking TMJ did not directly relate to the presence of TMJ pain nor the increased pain level. These indicate the need of further larger studies.

Structure of the normal synovial membrane of the temporomandibular joint: a review of the literature

PURPOSE

The structure of the normal synovial membrane of the temporomandibular joint (TMJ) is discussed, based on knowledge of synovial membrane in synovial joints in general.

The Christensen prosthesis. A retrospective clinical study

The objective of this study was to determine if the Christensen temporomandibular joint prosthesis system in an effective alternative in treating patients with severe temporomandibular joint disorders. A total of 69 patients who were not responsive to either nonsurgical or prior surgical treatments were placed into one of three treatment groups depending on the following diagnoses: (1) placement of a glenoid fossa-eminence prosthesis with meniscus retention (22 patients, 40 joints); (2) placement of a glenoid fossa-eminence prosthesis without retention of the meniscus (26 patients, 49 joints); (3) total joint replacement (21 patients, 34 joints). Patients were evaluated immediately before surgery and at regular intervals after surgery for an average of 3.1 years. Success was measured as a significant improvement of function and decrease in pain as measured on a visual analogue scale, as well as improved incisor opening as measured with a Therabite Scale (Lorenz Surgical, Jacksonville, Fla.). Comparison of mean and average pre- and postsurgical values for all groups and criteria showed significant improvement. Results of this study indicate that the Christensen temporomandibular joint prosthesis system may offer a viable method for the treatment of severe temporomandibular joint disease with a high degree of success.

Diagnostic accuracy of TMJ arthroscopy in correlation to histological findings

From 1987-1993, 356 arthroscopic examinations of the temporomandibular joint were performed on 295 patients. During 69 examinations, biopsies were obtained to correlate arthroscopic findings with histology. In the overall group, histology confirmed in 78.9% the arthroscopic findings. Correlation was better in joints with degenerative changes (81.5%) than in those with a synovitic/hyperaemic appearance (61.5%). Chondroid metaplasia, detritus synovitis and synovial chondromatosis were additional diagnoses given by histological examination. In 11 joints, open arthrotomy was performed after arthroscopy with biopsy was carried out. The excised tissue was also investigated microscopically and correlates to the biopsy-result. Because no different pathological changes were found, it is concluded that biopsies performed during arthroscopy of the temporomandibular joint are representative for histological investigation. An additional perforation for introducing the biopsy forceps is not necessary, because results obtained with different techniques appeared to be equally accurate.

An animal model for studying mechanisms in human temporomandibular joint disc derangement

PURPOSE

A method for producing disc displacement is presented in which remodeling events in the disc and posterior attachment (PA) are similar to those occurring in patients suffering from disc displacement (DD).

METHOD

Thirty-three adult New Zealand White rabbits were used in this study. A unilateral anterior DD was surgically induced in 18 animals. Six animals were sham operated and nine animals served as controls.

RESULTS

Macroscopically, DD was associated with gross thickening of the posterior band (PB), shortening of the disc anteroposteriorly, flexure of the intermediate zone (IZ), and loss of the biconcave shape. Microscopically, dramatic internal structural changes were observed in displaced discs, including extensive collagenous fiber reorganization and changes in cell morphology associated with a generalized loss of metachromatic staining. As in humans, the disc displacement caused abnormal loading of the PA and remodeling of this tissue into a disc-like structure characterized by the appearance of coarse collagenous fiber bundles and scattered chondrocytes surrounded by a matrix-containing cartilage-like glycosaminoglycans (GAGs).

CONCLUSION

These pathoanatomic changes bear a remarkable similarity to those described in human disc derangements and support the use of this method as an experimental model for the study of remodeling events in human DD arthropathies.

Synovitis in internal derangement of the temporomandibular joint: correlation between arthroscopic and histologic findings

PURPOSE

To define arthroscopic criteria for synovitis (SYN) reflecting specific histologic changes. Arthroscopic observations in the temporomandibular joint of patients with internal derangement were compared with histologic patterns in synovial biopsies obtained during arthroscopy.

PATIENTS AND METHODS

Arthroscopic biopsies were obtained in 31 joints of 31 patients using an oriented semiblind technique. The histologic changes in the biopsies were compared with those in age-matched reference material obtained at autopsy.

RESULTS

Microscopic examination of the reference material showed inflammation in three specimens (18%), whereas it showed inflammation in 22 patient specimens (71%). Biopsies from the patients also exhibited more pronounced inflammation. According to conventional criteria, arthroscopy showed mild SYN (increased vascularity) in 51%, moderate changes in 39%, and more pronounced changes in 10% of the joints. The presence of moderate or pronounced arthroscopic signs of SYN (capillary hyperemia and synovial hyperplasia), correlated well with the histologic diagnosis of SYN. This was in contrast to patients with mild arthroscopic SYN (increased vascularity).

CONCLUSION

Increased vascularity seen during arthroscopy must be questioned as a sign of SYN. More reliable criteria seem to be capillary hyperemia and synovial hyperplasia.

Histopathologic changes of the temporomandibular joint disk in patients with chronic arthritic disease. A comparison with internal derangement

Histopathologic examination was performed of the disk and the posterior attachment extirpated from 17 temporomandibular joints from 15 patients with chronic arthritic disease. Seven patients had rheumatoid arthritis (including two with juvenile type), five had ankylosing spondylitis, and three had psoriatic arthropathy, which affected more joints than the temporomandibular joint. Specimens removed from 16 temporomandibular joints from 15 patients with internal derangement were used for histopathologic comparison. In both groups of patients, inflammatory changes were observed, but no specific histopathologic signs could distinguish the groups. Patients with chronic arthritic disease seemed to have more pronounced changes of vascular proliferation, perivascular cellular infiltrate, inflammatory cells, and fibrosis throughout the soft tissues. Destruction of the disk was another finding evident in patients with chronic arthritic temporomandibular joint disease; there was no visible disk structure in 8 of these 17 joints, compared with 1 of the 16 joints in the internal derangement group.

Diagnosis of intracapsular pathology associated with temporomandibular joint disorders

The clinical diagnosis of a Temporomandibular Disorder (TMD) has traditionally been based on data gathered by means of a medical history and physical examination. The most common signs and symptoms associated with TMD are reduced jaw opening, pain and elevated tenderness in the muscles of mastication, pain and elevated temporomandibular joint (TMJ) tenderness, and TMJ noises upon movement. These signs and symptoms are routinely detectable by a skilled clinician upon examination. Unfortunately, the clinical problem described globally as a TMD has several different and overlapping patho-physiologic disease processes, and a traditional clinical examination does not provide highly tissue-specific pathologic information. Were it readily available, such information would be greatly useful, since logical and accurate treatment planning requires that each disease process be correctly identified. One important challenge for researchers interested in TMD will be the careful definition and subsequent validation of diagnostic methods which identify the relevant ongoing pathological disease process. On such research area, which has great promise, is the establishment of a valid diagnostic technique for intracapsular pathologies unique to TMD patients. This paper provides a critical review and discussion of the diagnostic validity of TMJ arthroscopy and other related methods of identifying intracapsular pathologies associated with TMD.

Reliability and validity of imaging diagnosis of temporomandibular joint disorder

The purpose of this article is to review reliability and validity of imaging diagnosis of temporomandibular joint disorders. Plain-film and tomography are basic imaging techniques for assessment of the temporomandibular joint. These can be used for evaluation of osseous disease and as a baseline for follow-up. In patients with symptoms from the joint, plain-film and tomography are rarely definitive, and evaluation of the soft tissues is frequently necessary. Arthrography, computed tomography, and magnetic resonance imaging have all been used for evaluation of the soft-tissue components of the joints. Accuracy studies of these techniques have demonstrated the highest diagnostic accuracy for magnetic resonance imaging. Arthrography is relatively insensitive for detection of medial and lateral displacements. Magnetic resonance imaging accurately depicts both hard and soft tissues, and this technique is emerging as the prime diagnostic imaging technique in patients presenting with clinical signs and symptoms of a disorder of the temporomandibular joint. The most frequent findings when patients with clinical symptoms of temporomandibular joint disorders are "imaged" are different forms of disc displacement and degenerative joint disease. Studies have demonstrated a high prevalence of different forms of disc displacement in patients, although these abnormalities are also seen in some asymptomatic volunteers. Future research should further refine imaging techniques to come closer to an understanding of the association between morphologic alterations and patient symptoms.

Disk derangement and inflammatory changes in the posterior disk attachment of the temporomandibular joint. A histologic study

Temporomandibular joint disk derangements were investigated in 42 patients (47 joints) with respect to occurrence and degree of histologic inflammation in the posterior disk attachment and compared with reference material obtained at autopsy. Sensitivity and specificity for arthroscopy versus macroscopic observation at arthrotomy in regard to inflammation were also investigated. On histologic examination, inflammation was found in 1 joint (5.5%) in the reference material and 30 joints (64%) in the patients where pronounced inflammation was found in 6 joints (20%). Arthroscopy revealed inflammation more accurately (sensitivity 0.94%, specificity 0.86%) than macroscopic observation at arthrotomy (sensitivity 0.58%; specificity 0.90%).