With the aim of formulating clinical practice guidelines for the initial treatment of temporomandibular disorders (TMD), we carried out semi-structured interviews with volunteer patients who had suffered from TMD for the purpose of collecting patient question. The subjects (informants) were recruited through two newspapers. The guidelines committee chose 10 subjects from the 19 applicants through careful discussion. The interviews were conducted by trained interviewers in a special interview room, and the answers given by the informants were tape-recorded and transcribed into sentences. From these sentences, important words and phrases were extracted using a text mining method. When asked about their understanding of TMD, four informants answered "A disease with jaw displacement" and another four said "A disease that occurs when one's occlusion is not good." Only one informant had been correctly educated about TMD by the dentist. Three informants had received mouthpiece therapy but none knew the importance of and reasons for providing this therapy. Six informants were satisfied with the treatment they had received, but two were not. Usually, mouth-opening exercises, massages, and compresses were chosen as management therapy for problems of joint noise, restriction in mouth opening, or joint pain; this was followed by jaw rest, chiropractic treatment, and mouthpiece therapy. This investigation revealed that all informants had only a superficial knowledge about the pathological conditions and treatment methods for TMD. It is suggested that dentists should provide patients with adequate education regarding the symptoms and treatments of TMD.

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We report a case of masticatory muscle tendon-aponeurosis hyperplasia in which was observed regeneration of tendon and aponeurosis after coronoidectomy and aponeurectomy on MRI.
A 59-year-old woman was referred to our hospital for trismus. Her maximum mouth opening was 20mm, and a dense band was palpable along the anterior border of the masseter muscles on maximum mouth opening. MRI showed that thickened aponeurosis extend well into the anterior margin of the masseter muscles.
Bilateral aponeurectomy and coronoidectomy were carried out via an intraoral approach under general anesthesia. One year after operation, the interincisal opening was 47mm, and regeneration of the masticatory muscle tendon, aponeurosis and coronoid process were observed.

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Background: We have analyzed the gene expression profile of synovial cells from the temporomandibular joint (TMJ) to identify candidate genes associated with intracapsular inflammation of the TMJ. Macrophage-colony stimulating factor (M-CSF) gene was up-regulated in synovial cells after stimulation with interleukin (IL)-1β, a cytokine thought to play a key role in several inflammatory conditions. In the present study, we investigated the expression of M-CSF in cultured synovial cells from human TMJ and rat TMJ synovial tissue stimulated with IL-1β.
Methods: Total RNA was isolated from human synovial cells after IL-1β treatment. M-CSF expression was analyzed using GeneChip, RT-PCR, and real-time PCR. In addition, M-CSF protein production was measured using enzyme-linked immunosorbent assay. Synovial tissue from the TMJs of IL-1β-injected rats was examined for M-CSF expression by immunohistochemical staining.
Results: The gene expression of M-CSF in synovial cells was increased up to 8h after IL-1β treatment, and protein production also increased depending upon both time course and IL-1β concentration. Immunohistochemistry revealed positive staining for M-CSF in synovial tissues of the TMJ in IL-1β-injected rats. In contrast, no positive cells were found in control rats.
Conclusion: IL-1β increased M-CSF gene expression and M-CSF protein production in synovial cells.

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We report a case with severely adhered and calcified TMJ disc due to insufficient postsurgical rehabilitation after TMJ arthrocentesis and arthroscopic lysis and lavage. The patient was a 33-year-old man who was referred to our department with the chief complaint of pain of the left TMJ region and limitation of mouth opening (maximal interincisal opening: 26 mm) in April 2007. Although he had been treated by conservative therapies and left TMJ arthrocentesis in 2000, followed by left TMJ arthroscopic lysis and lavage in 2003, the postoperative rehabilitation was insufficient due to noncompliance with the instructions. He was clinically diagnosed as having TMJ disc adhesion with calcification by imaging modalities, and open arthroplasty of the left TMJ was performed. Postsurgical rehabilitation was successfully continued by a customized rehabilitation protocol for the patient and a calendar-based checklist for mouth-opening exercises. Two years after the arthroplasty, the postoperative conditions were good, showing painless TMJ and maximum interincisal opening of 40 mm. This case suggests that successful postoperative rehabilitation is one of the most important factors for obtaining a successful outcome after TMJ surgery.

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Objective: We report on the pain-related limitations of daily function using a new questionnaire (LDF-TMDQ) in Japanese patients with temporomandibular disorders (TMD). The LDF-TMDQ consists of 10 questions and can estimate three latent variables: "limitation of mouth opening", "limitation in executing a certain task", and "limitation of sleeping". We have already verified the validity of the construct and cross validity of the LDF-TMDQ. The purpose of this study is to assess the reliability of LDF-TMDQ in Japanese TMD patients.
Methods: All outpatients were asked to complete the LDF-TMDQ as a pre-examination at their first visit. Those patients diagnosed as having painful TMD were requested to complete the LDF-TMDQ again on the same day after they had returned home. A total of 103 TMD patients were recruited consecutively, and 77 (75%) completed the LDF-TMDQ and were eligible for analysis. The test-retest reliability was assessed using intraclass correlation coefficients (ICC), and Spearman's correlation coefficients using SPSS (ver. 12). Internal consistency was assessed using Cronbach's α.
Results: The test-retest reliabilities of ICC for "limitation of mouth opening", "limitation in executing a certain task" and "limitation of sleeping" were 0.71, 0.71 and 0.83; Spearman's correlation coefficients were 0.69, 0.71 and 0.79 (p< 0.001); and Cronbach's α values were 0.83, 0.83 and 0.91, respectively.
Conclusion: This study showed that LDF-TMDQ has excellent within-day reliability.

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Suppurative arthritis of the temporomandibular joint is a relatively rare condition and with the development of antibiotics, there are few chances of encountering affected patients in clinical situations. In the present report,we describe a case of an abscess in the infratemporal fossa that was induced by acute suppurative arthritis of the temporomandibular joint.
The patient was a 62-year-old woman who had been suffering from pain in the right temporomandibular joint when opening the mouth, and from limitation of mouth opening for about 1 month before visiting our department. She also complained of spontaneous pain centering around the right temporomandibular joint toward the right buccal region, tumefaction, and occlusal insufficiency. A hematological examination revealed an abnormally high white blood cell count of 8,000 and CRP of 15.1.No evident causal tooth was found in the oral cavity. Moreover, an MRI examination revealed a high-intensity signal in the area corresponding to the upper articular cavity and she was diagnosed with an abscess in the infratemporal fossa.
On the day of diagnosis,the lower part of the right zygomatic arch was cut open under general anesthesia to relieve the infratemporal fossa,where a large amount of purulent discharge was found.Thanks to postoperative antimicrobial chemotherapy treatment,the symptoms rapidly improved to allow discharge on the 9th day after entering the hospital.At the time of writing,the patient has shown a favorable course without sign of recurrence.

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Ankylosis spondylitis (AS) is classified as seronegative spondylarthropathy, and is rare in Japan. We report a case of AS detected by difficulty of mouth opening. The patient was a 48-year-old female who visited our department in May 2007 with limited mouth opening (range of mouth opening: 14 mm). She also suffered from severe limited neck mobility, uveitis, and aortic regurgitation (AR). In another hospital, aortic valve replacement was planned for AR under general anesthesia, and it was necessary to remove the focus of infection in the mouth for the prevention of postoperative endocarditis. Plain X-ray findings showed bone deformity of the spine as well as temporomandibular joint. Computed tomography findings also showed severe deformity of the glenoid fossa and condyle, and the disc was unidentified. The laboratory findings showed a slight increase of CRP level, increased value of ESR, negative for rheumatoid factor, and positive for HLA-B27. From these findings, the possibility of AS in this case was considered. The patient was referred to orthopedic surgery, and a diagnosis of AS was confirmed. We performed conservative treatment for her symptoms: the range of mouth opening increased to 25mm, and the focus of infection in the mouth was removed. Aortic valve replacement was done without problem. The patient's condition remains stable and the range of mouth opening is unchanged after the surgery.

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