Natsuki Segami

Correlation between pain and synovitis in patients with internal derangement of the temporomandibular joint

A correlation between pain scores by questionnaire and synovitis index via arthroscopic inspection was made in 28 patients with internal derangement of the temporomandibular joint (TMJ) with closed lock. A statistically significant but weak correlation was found between the visual analog scale of pain and the index of distribution of synovitis. However, in the questionnaire, pain on chewing had a positive correlation with both the intensity and distribution of synovitis in the TMJ. This study indicates that synovitis is one cause of TMJ pain in patients with closed lock.

Short-term treatment outcome study for the management of temporomandibular joint closed lock. A comparison of arthrocentesis to nonsurgical therapy and arthroscopic lysis and lavage.

OBJECTIVE The aim of this study is to compare the clinical short-term results and efficacy of arthrocentesis with those of nonsurgical treatments and arthroscopic surgery for the management of temporomandibular joint closed lock. STUDY DESIGN The three groups consisted of 63 consecutive patients treated nonsurgically, 20 patients treated with arthrocentesis, and 25 patients treated with arthroscopic surgery. All patients rated their pain level on a visual analogue scale and completed a pain, jaw dysfunction, and activity-limiting questionnaire before and 6 months after the procedure. Each patients jaw opening was also scaled. The success rate of each procedure was calculated according to our success criteria. The clinical efficacy of each procedure was evaluated in successfully treated subgroups in which the between-group and within-group differences of the obtained data were statistically tested. RESULTS The success rate was 55.6% in the nonsurgically treated group, 70% in the arthrocentesis group, and 91% in the arthroscopy group. With respect to efficacy, all posttreatment scores showed significant improvements in within-group differences, but no between-group differences were found between the arthrocentesis group and the other two groups. CONCLUSION Arthrocentesis was considered as an intervening treatment modality between nonsurgical treatment and arthroscopic surgery on the basis of its short-term outcome. Although the treatment efficacy was comparable with arthroscopic surgery, this procedure was thought to be indicated for the patients with acute temporomandibular joint closed lock who were refractory to medication and mandibular manipulation rather than the alternative of arthroscopic surgery.

Importance of proinflammatory cytokines in synovial fluid from 121 joints with temporomandibular disorders

The concentrations of cytokines were measured by an ELISA in the synovial fluid from 117 patients with temporomandibular disorders (TMD) and correlated with degenerative changes of the condyle and clinical symptoms.Fifty-seven patients had degenerative changes of the condyle. The fluid from seven healthy volunteers was used as controls. The concentrations of interleukin-1beta (IL-1beta), tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-8 (IL-8) were significantly higher in the synovial fluid of patients than controls (P<0.05). The concentration of IL-6 was significantly higher in the patients with degenerative changes than in other patients (P<0.05). The detection of IL-8 correlated with the concentrations of IL-6 and TNF-alpha. However, there was no correlation between the concentrations of any cytokines and symptoms. In conclusion, the cytokines in the synovial fluid may participate in the pathogenesis of TMD. In particular, IL-6 is important and may be associated with the development of osteoarthritis.

Correlation between pain and dysfunction and intra-articular adhesions in patients with internal derangement of the temporomandibular joint

The correlation between pain and dysfunction scores obtained by questionnaire and an adhesions index obtained via arthroscopic inspection was investigated in 28 patients with internal derangements (closed lock) of the temporomandibular joint (TMJ). A weak correlation was found between pain scores and the adhesions index. However, joint noise had a negative correlation with both severity and distribution of adhesions in the TMJ. A weak, but statistically significant, negative correlation also was found between the degree of interincisal opening and the adhesions index. This study indicates that intra-articular adhesions are one of the factors contributing to limited mouth opening in patients with closed lock, but that they do not cause TMJ pain.

Four-year follow-up study of temporomandibular joint arthroscopic surgery for advanced stage internal derangements

PURPOSE This study evaluated the long-term outcome after temporomandibular joint (TMJ) arthroscopic surgery for patients with internal derangement with stage V disease. MATERIALS AND METHODS Fifteen female patients (24 TMJs) who underwent arthroscopic surgery were evaluated by a questionnaire preoperatively and postoperatively 3 to 5 years later (mean: 4 years, 2 months). The questionnaires consisted of a visual analog scale, pain and jaw dysfunction scores, and self-measured interincisal opening. Clinical examination and conventional radiographic evaluation were done in nine patients (13 joints). Postoperative magnetic resonance imaging was done in two patients (3 joints). RESULTS All post-treatment scores showed a statistically significant improvement, although joint noise remained in some patients. The radiographic examination revealed mild to moderate degenerative changes, but no abnormal resorption was detected. The surgical success rate was 93.3%. CONCLUSION Arthroscopic surgery is a useful, minimal invasive, surgical procedure for advanced stage internal derangement of the TMJ.

The effect of fibroblast growth factor-2 on the osteoinductive activity of recombinant human bone morphogenetic protein-2 in rat muscle.

To clarify the effect of recombinant human basic fibroblast growth factor (FGF-2) on the osteoinductive activity of recombinant human bone morphogenetic protein-2 (BMP-2) in vivo, different amounts of FGF-2 (0, 16, 80 and 400 ng, and 2, 10 and 50 micro g: n=10 in each group), BMP-2 (2 micro g) and type I collagen as a carrier were mixed and implanted into rat calf muscles. Three weeks after implantation, compared with the controls, the radiopaque shadows of the implants were increased in the 16, 80 and 400 ng FGF-2-treated groups, but decreased in the 2, 10 and 50 micro g FGF-2-treated groups. In addition, alkaline phosphatase activity was increased in the 16, 80 and 400 ng FGF-2-treated groups but decreased in the 50 micro g FGF-2-treated group. Histological examination revealed increased bone formation in the 16, 80 and 400 ng FGF-2-treated groups. These results show that combined treatment with FGF-2 and BMP-2 has a biphasic effect on osteoinductive activity, i.e. it increases with low doses of FGF-2 and decreases with high doses of FGF-2.

Congenital deformities and developmental abnormalities of the mandibular condyle in the temporomandibular joint

ABSTRACT  The temporomandibular joint (TMJ) consists of the mandibular condyle and the articular eminence of the temporal bone. The morphological development of the TMJ during prenatal life lags behind other joints in terms of both the timing of its appearance and its progress. At birth, the joint is still largely underdeveloped. There are many causes of the various growth disturbances and abnormalities of the mandibular condyle and related structures. Growth disturbances in the development of the mandibular condyle may occur in utero late in the first trimester and may result in disorders such as aplasia or hypoplasia of the mandibular condyle. Meanwhile, hyperplasia of the mandibular condyle is not visible at birth and seems to be gradually acquired during growth. In the present review article, the congenital abnormalities of the mandibular condyle are classified morphologically into three major groups and two subgroups from a clinical standpoint: (1) hypoplasia or aplasia of the mandibular condyle, including (i) primary condylar aplasia and hypoplasia, (ii) secondary condylar hypoplasia; (2) hyperplasia; and (3) bifidity. In addition, the molecular‐based etiology of anomalies of the mandibular condyle is also discussed.

Interleukin-6 family of cytokines as biochemical markers of osseous changes in the temporomandibular joint disorders

The aim of this study was to find out whether there was a correlationship between the concentrations of interleukin-6 (IL-6), IL-11, and IL-17 in synovial fluid and osseous changes in the condyle. The synovial fluid was obtained from 61 patients with temporomandibular joint disorders (TMD) and seven healthy volunteers (controls). The concentrations of IL-6, IL-11, and IL-17 were measured by enzyme-linked immunosorbent assay. IL-6 was detected in 43 of 59 (73%), IL-11 in 23 of 52 (44%) and IL-17 in 14 of 51 (27%) samples of synovial fluid. The concentrations of IL-6 and IL-11 in the joints with osseous changes in the condyle were significantly higher than in the joints without osseous changes (P < 0.05) and also higher than in the joints of the control group (P < 0.05). In addition, there was a correlation of concentrations between IL-6 and IL-11 (P < 0.05). These results suggest that IL-6 and IL-11 may participate in the pathogenesis of TMD and induce osseous changes in the condyle.

Expression of interleukin 6 in synovial tissues in patients with internal derangement of the temporomandibular joint.

Using an immunohistochemical technique, we examined synovial tissue from 46 temporomandibular joints (TMJ) with internal derangement in 44 patients. As controls, we examined synovial tissue specimens from 7 joints with habitual dislocation without pain. In synovial tissues from 21 of the 46 joints with internal derangement, interleukin 6 (IL-6) was expressed in the synovial lining cells and in the mononuclear cells infiltrating the periphery of the blood vessels. The density of IL-6-stained cells in specimens with internal derangement correlated significantly with the grade of joint effusion shown by magnetic resonance imaging (P=0.01, r=0.32).

Increased Levels of Soluble Cytokine Receptors in the Synovial Fluid of Temporomandibular Joint Disorders in Relation to Joint Effusion on Magnetic Resonance Images

PURPOSE The purpose of this study is to clarify the significance of joint effusion (JE) on T2-weighted magnetic resonance images of the temporomandibular joint (TMJ) in comparison to various soluble cytokine receptors in the synovial fluid of patients with temporomandibular disorders (TMDs). PATIENTS AND METHODS Magnetic resonance imaging of 55 TMJs of 55 patients with TMD was performed, and synovial fluid samples were obtained on the same day. The grade of JE was evaluated on a scale from 0 to 3, with grade 0 indicating the absence of JE and grades 1 to 3 indicating the presence of JE. Correlations were measured between JE and the concentrations of soluble tumor necrosis factor receptors I and II, interleukin (IL) 6 soluble receptor, IL-1 soluble receptor type II, and IL-1 receptor antagonist and protein in the synovial fluid samples. RESULTS The mean concentrations of cytokine receptors in the synovial fluid were significantly higher in the 30 joints with JE than in the 25 joints without JE. There were no correlations between the JE grade and the level of any mediators. CONCLUSION Increased levels of cytokine receptors are likely to influence the expression of JE and may play important roles in the pathogenesis of TMD. These results also suggest that JE may reflect synovial inflammation of the TMJ.