Although there is a wealth of literature concerning the evaluation of the treatment of temporomandibular joint dysfunction (TMJ arthrosis), there are few studies of the long-term results and the finalization procedure. In this paper we evaluated the long-term follow-up after phase II management (occlusal treatment) of 44 patients who were treated successfully with stabilization bite plane, by means of questionnaire.
The questionnaires were returned by 40 patients (90.9%). The asymptomatic rate was 35% (14 patients), and 26 patients (65%) had several symptoms. Fifteen patients had noise in the TMJ or opening difficulty that were not found at their first visit. It raised the suspicion that diseases might progressive in these patients. Fifteen patients answered that they have had a recurrence of symptoms. Then evaluating the non-recurrent cases 62.5% of the patients were successfully treated with stabilization bite plane therapy followed by occlusal treatment. All recurrence took place within a year of treatment. Occlusal treatment seemed to decrease the recurrent rate. We conclude that an appropriate phase II management and long-term follow-up are necessary in the management of TMJ dysfunction (TMJ arthrosis).

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Morphology and function are closely related in many parts of the human body. In this study, we attempted to find out the relationship between the form and function of condyles, using the two dimensional finite element method and the shape optimization method. Four typical frontal condyle shape (Yale et al. 1963) models were prepared. Each model consisted of cortical and cancellous bone where known physical constants were applied. Force was applied at the neck of the simulated condyle at angles of 90, 105 and 75 degrees. Constraints were put on various parts of the condyle surface. In the area with higher compressive stress than the threshold level the condyle shape was modified by moving some nodes proportionally to the discrepancy between the actual and the threshold stress level. The results suggested that the interrelation among condyle shapes, angle of applied forces and constraint condition could significantly alter the condyle morphology.

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The purpose of the present study is to investigate the association between temporomandibular disorders (TMDs) and malocclusions in a statistical aspect. A total of 305 untreated orthodontic patients, consisting of 232 non-CLP and 73 CLP patients, were selected as the subjects. For each subject, TMD symptoms and malocclusions were evaluated. If several types of malocclusion were found in a subject, all the malocclusions were included during data sampling. The following TMD symptoms were examined: TMJ sounds, TMJ pain, muscle tenderness and difficulty of jaw movement. The difficulty of jaw movement means mandibular opening of 35mm or less and/or mandibular lateral shift of 5mm or more.
The prevalence of TMDs in the non-CLP and CLP subjects were 21.1% and 12.3% respectively. No significant differences were found between the prevalences in the two groups of subjects. In both groups, there was no significant difference in the TMD prevalence between the sexes.
The prevalence of TMDs increased substantially with age, and thus significant association was found between age and prevalence in the non-CLP subjects.
The prevalence of TMDs was higher in the patients with open bite than those with other types of malocclusions. In addition the prevalence of TMJ sounds exhibited the highest value. Further, significant assohiation was foundbetween each malocclusion and a specified TMD symptom; i.e. open bite versus TMJ sounds, deep bite and posterior cross-bite versus difficulty of jaw movement, and crowdind versus TMJ pain.
It is shown that certain types of malocclusion pertain significantly to the occurrence of TMD symptoms.

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Serum propitocain levels following intraarticular injection (40mg) were studied in the adult human temporomandibular joint (TMJ). Propitocain was assayed by gas chromatography. Venous serum levels were measured at 5, 10, 15, 20, 30, 45, 60 and 90 minute intervals following a single injection into the TMJ. The maximum concentration (0.115±0.019μ/ml) occurred 30 minutes after injection. The concentration was decreased slowly at 90 min after injection. These results suggested that the transport of propitocain from the articular cavity into the capillary lumen was slow compared with the upper respiratory tract.

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Eighteen temporomandibular joint arthrosis patients with TMJ pain were investigated to determine the effectiveness, side effects complication and safety of sodium hyaluronate therapy. 0.5ml of sodium hyaluronate (ARTZ^®) were injected into the painful TMJ of each patient once a week for 4 weeks.
The results were as follows.
1. The vertical interincisal distances significantly increased immediately after injection. But one week later the interincisal distances had decreased nearly up to these before injection. 1 month after injection the mean of interincisal distances again increased significantly.
2. The effectiveness rate (markedly effective and moderately effective), 1 month after injection, was 83% for spontaneous pain, 100% for mouth closing pain, 70% for joint tenderness and 41% for mouth opening pain.
3. Half of the patients who had joint sound before injection found that their click or crepitus had disappeared or lessened 1 month after injection.
4. Complications, including abnormal sensation, swelling sensation, dull sensation and uncomfortable spontaneous pain, mouth opening pain at the site of the joint where the medium was injected or trismus, wera recognized in 56% of cases. All the patients with spontaneous pain complain of some complication.
5. It is concluded that intra-articular injection therapy of hyaluronic acid for the painful temporomandibular joint with TMJ arthrosis is rather safe and useful.

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This study was undertaken to clarify the different clinical symptoms and surgical outcomes, depending on the severity of articular pathology in internal derangements of the temporomandibular joint (TMJ).
The materials were 61 consecutive joints in 49 cases with persistent closed lock, which had received arthroscopic antero-lateral capsular release. The materials were classified according to their symptoms, imagings and arthroscopic features in the superior compartments, using the staging criteria proposed by the American Society of TMJ Surgeons in 1990.
The patients were divided into 3 stages as follows; stage III in 28 joints, stage IV in 19 joints, and stage V in 14 joints. The surgical success rate was 92.9% (26/28 joints) in stage III, 94.7% (18/19 joints) in stage IV, and 100% (14/14 joints) in stage V. The postoperative opening degree as well as objective scoring of arthralgia and dysfunction by questionnaire revealed no difference in each stage. In conclusion, it appeared that arthroscopic antero-lateral capsular release was equally effective in improving the clinical symptoms even in the advanced stages of internal derangements of the TMJ.

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This anatomical study was undertaken to clarify the incidence of successful puncture, as well as the possibilty of iatrogenic damage to the articular tissue by arthroscopic puncture of the inferior compartment of the temporomandibular joint (TMJ).
The materials were 38 TMJs in 19 fresh adult cadavers, which disclosed to abnormality on the preauricular area. Three joints were excluded because of disk perforation in the superior compartment caused by earlier arthroscopy. It was found that inferior joint arthroscopy was complete in 77.1% joints (27/35), and of these the anterior recess was visible only in 18.5% joints (5/27). In the findings at dissection, iatrogenic disk perforation was identified in 40.7% joints (11/27). Iatrogenic scaffing of condylar cartilage occurred in all joints (27/27).
In conclusion, inferior compartment arthroscopy causes damage to the articular tissues with high risk. A reliable puncture procedure should be developed for secure arthroscopy of the inferior compartment of the TMJ.

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Reciprocal clicking is known to be associated with anterior disc displacement with reduction. Condylar movements in reciprocal clicking temporomandibular joints is considered to reflect the state of the anterior disc displacement. Their 3-dimensional aspect, however, has not yet been clarified, due primarily to the difficulty in recording. We therefore recorded and analyzed condylar movements in three-dimensions in 15 subjects who had both reciprocal clicking clinically and also a figure of eight-shaped condylar movement pattern in their sagittal condylar path. We determined the condylar positions just before and immediately after clicking, using the deflection in condylar trajectory, and the rapid change of its velocity. The pre-clicking position in opening was observed, in most cases, anteromedially and 4.3±2.37mm distant from the intercuspal position, on average. The condyle usually deviated antero-laterally during clicking, which seemed to agree with the fact that the disk tends to dislocate antero-medially. We then measured the distance between the pre-clicking position and the line connecting the intercuspal and post-clicking positions, in the condylar path. This distance of the clicking in protrusion was 0.8±0.29mm, on average. These results suggested that condylar movement reflects the exact details of the internal derangement of the TMJ.

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We analyzed the center of gravity fluctuation before and after the initial treatment in 8 craniomandibular disorder patients to clarify the relation between the stomatognathic system and the systemic condition.
The results were as follows: the majority of patients initial treatment showed tendencies to decrease in these respects, convergence of the mean gravity position, and the length and area of the center of gravity fluctuation.
It appears that muscle tonus or condyle displacement stimulate the propriocepter. Furthermore, the disorder of afferent signals influence directly or indirectly the middle ear, labyrinth and brainstem. So, the craniomandibular disorder changes the center of gravity fluctuation.
These findings, namely the influence of craniomandibular disorder on the center of gravity fluctuation and equilibrium suggest that there is some relation between the stomatognathic system and the systemic condition.

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Orthodontic occlusul reconstruction is an effective non-invasive treatment for craniomandibular disorders. However, the full-mouth orthodontic techniques usually used are not always applicable for the treatment of the disorders, because the treatment requires high-level accuracy and durability to determine and to maintain the ideal mandibular position. Therefore, we often use limited orthodontic treatment, which moves several teeth regionally, in combination with prosthodontic treatment.
In this article, we classify orthodontic and prosthodontic combination therapy into three categories: a combination of a removable CMO appliance and limited tooth movement, a combination of provisional fixed CM repositioners and limited tooth movement, and orthodontic occlusal reconstruction. The aims and techniques of orthodontic and prosthodontic combination therapy for cranio-mandibular disorders are described with some clinical cases.

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Knowledge about age-related changes of the temporomandibular joint (TMJ) in ICR mice is of great interest for the understanding of histopathological alterations of the human TMJ. These changes are sometimes called degenerative or spontaneous osteoarthritic changes.
However, there is a scarcity of information in the literature on morphologic changes due to normal age changes, in ICR male mice. The purpose of this investigation is to observe the age-related changes of ICR mice.
As a result it was recognized that the main part of age changes was in the cartilaginous layer in articular surface of the condyle. The mesenchymal cell layer was thickened and the hypertrophic chondrocytes decreased and clustered. These findings were coincided with the changes in human condylar materials.

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