This study was designed to investigate postnatal changes in innervation in rat TMJ disk, using immunohistochemical methods with antibodies against PGP 9.5 and CGRP.
Twenty-eight Wistar strain rats (0-40-day-old) were perfused through the left venticle. The tissue blocks including the temporomandibular joint were carefully removed, decalcified, and finally cut into sagittal and/or frontal serial sections. The sections were processed for the immunohistochemical staining using the labeled-streptavidin-biotin method. A few nerve fibers, which invaded near the middle area at birth, became localized in the peripheral area. In the peripheral area, the number of nerve fibers increased during the postnatal development. No special nerve terminals were observed, although varicosity-like structures regarded as the free nerve endings increased during postnatal development.
It was suggested that the postnatal development of the nerve fibers in the articular disk is associated with the development of the occlusion and the joint structure.

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Mandibular movement of a 59-year-old female having rheumatoid arthritis was analyzed with a six-degree of freedom jaw tracking device. Severe bilateral condylar resorption was revealed in 3D-CT resulting in anterior open bite. From the jaw tracking record, the posterior reference point defined as the narrowest paths during mandibular border movement was not determined in the TMJ region but was 20mm lower than where the condylar point should have been. Although it is well known that the condylar point on the working side hardly moves during mandibular lateral movement, the working side posterior reference point of the patient moved as much as 4mm backward. Veneer crown restoration was performed to increase occlusal support in the molar region. Due to the specific anatomical and kinesiological aspects, flat occlusal surface in the molar region was placed to allow more freedom in lateral movement.

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Surgical treatment is considered to be the most effective method to cure recurrent dislocation. However, surgery can not be performed in all cases because of the stress or the temporomandibular joint and surrounding tissue. Therfor, effective conservative treatments are needed. A case of unilateral recurrent dislocation that was cured by means of mandible exercises was reported.
The patient was a 21-year-old female with recurrent dislocation of the right temporomandibular joint at large opening. The dislocation was thought to be due to hypermovement of the right condyle compensating for limitation of left condylar movement owing to anterior disc displacement. Treatment was focused on mobilization of the left condyle by right-trusive and straight-opening exercises of the mandible using laterotrusive training device. After the treatment, the dislocation was improved, with coordination of bilateral condylar movements and straight opening.
Thus, in cases of dislocation of the temporomandibular joint that may have been caused by a limitation of unilateral condylar movement on the nondislocation side, treatment to overcome this limitation may be effective for correcting the dislocation.

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Various complications in the head and neck region related to hemodialysis therapy have been reported, however, changes of temporomandibular joint have not been investigated yet. Two patients with morphological bone deformities in bilateral condylar head assessed by several kind of imaging which were strongly suspected in relation with dialysis bone disease were presented. The purpose of this study was to investigate epidemiologically the actual functional condition of temporomandibular joint by a questionnaire.
Subjects were 263 patients, 188 males and 75 females, undergoing by hemodialysis treatment for chronic renal failure in Shinrakuen Hospital, Niigata. The average age was 55.6±11.4 (mean±S. D.) years old and the mean period of hemodialysis treatment was 11.1±8.5 years. As a result of this questionnaire, patients with any temporomandibular symptoms (TMJ pain, trismus, abnormal sound, muscle pain, sense of occulusal incongruity) were 79 patients (30.0% of all), 62 males and 17 females, mean age of 54.06±12.52 years old and mean period of hemodialysis treatment was 13.22±9.04 years of which statistical relationship between total subjects and patients with any temporomandibular symptoms was significant (p<0.01, Mann whitney U test).
Some changes of temporomandibular joint affected by long-term hemodialysis are strongly suspected in this study.

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This study was conducted to investigate the effects in superior articular cavity adhesion with closed lock cases based on the arthrocentesis and pumping-manipulation therapy. In general the fact that articular cavity adhesions were related to symptoms which occurred as trismus and pain in mouth opening with closed lock was eliminaled by surgical techniques. Arthrocentesis and pumping-manipulation therapy is the simplest and least invasive of all surgical techniques, and is highly successful in acute closed lock cases. In this study, arthrocentesis and pumping-manipulatoin therapy was conducted on 40 cases of closed lock patients and double contrast Herical CT Multiplanar Reconstruction Images (MPR) was performed concurrently. The effects of adhesion on closed lock were inivestigated from the results of the therapy. The results were as follows: 32 cases obtained the increased mouth opening (40.0mm over), and 35 cases were alleviated of pain at maximal jaw opening. The ratio of adhesion was 28 cases (70.0%), however many cases of adhesion were obtained with good results by the therapy only. It was said that the therapy had several actions which excluded fibrlilation and slight adhesion but it was unthinkable that those actions were performed completely. Thus this therapy cannot treat adhesion, but adhesion has no effect on treatment of closed lock against conventional theory. From the above, it was inferred that many cases of closed lock were involved with superior articular cavity adhesion and adhesion did not prevent treatment.

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