Arthroscopic examination has great potential for assessment of temporomandibular disorders associated with fibrous adhesions and/or synovitis in the superior joint compartment instead of MRI which we use frequently. However, there have been few reports on the relationship between the effect of arthrocentesis and the conditions of fibrous adhesion and/or synovitis. In this study, we investigated the effect of arthrocentesis on internal derangement of the temporomandibular joint (TMJ) based on arthroscopic findings. Our subjects included 175 patients with 182 joints (17 in 17 males and 165 in 158 females with an average age of 41.0±16.0) who underwent arthrocentesis of the superior joint compartment and arthroscopic examination at the same time. We used an arthroscope with a small diameter (M & M Co. Ltd. ) : lesions and the grade of fibrous adhesions and synovitis were evaluated at nine sites in the superior joint compartment. We also used a questionnaire about symptoms and a Visual Analogue Scale (VAS) to assess pain in the TMJ at one month after the arthrocentesis.
At arthroscopy, there were fibrous adhesions on the anterolateral to anterior part of the articular cavity, and synovitis at the middle to posterior region. At one month after treatment, opening was improved in 53.8% of the patients, and 64.3% of them showed improved VAS scores for TMJ pain. Arthrocentesis had more effect when there were slight fibrous adhesions and synovitis than in extensive cases. Our results indicated that conducting arthroscopic examination at the time of arthrocentesis is useful for understanding the clinical condition and the prognostic expectation of internal derangement of the TMJ.

View full abstract

On sagittal T1-weighted MRI, the posterior disk attachment (PDA) usually has high signal intensity, but sometimes shows decreased signal intensity in temporomandibular joints (TMJ) with anterior disk displacement. This change in signal intensity in the PDA suggests pseudodisk formation (adaptive change of the PDA), but cross-sectional studies had demonstrated no significant association between decreased signal intensity and joint pain. The purpose of this study was to determine whether the signal intensity in the PDA following arthrocentesis is associated with improvement in clinical findings and adaptive changes of TMJ.
The study group consisted of 38 patients with 41 joints with TMJ disorder showing high signal intensity in the PDA in pretreatment MRI. All joints were reevaluated by MRI after improvement in joint pain and range of motion (ROM) following arthrocentesis. Posttreatment MRI was performed on average 20.3 months after initial MRI. Clinical and MRI findings (disk reduction and configuration, and condylar translation and bone changes) were compared between joints with decreased signal intensity (decreased signal group) and joints with high signal intensity (high signal group) in the PDA.
Seventeen joints (41.5%) showed decreased signal intensity in the PDA. Postarthrocentesis pain visual analogue scale (VAS) and ROM as well as the degree of improvement in them of the decreased signal group were not significantly different from those of the high signal group. Condylar translation significantly improved and disk deformity significantly progressed in both groups. Disk reduction was seen in only one joint with the high signal group and significant changes in bone changes were not seen in either group. All posttreatment MRI findings were not significantly different in either group.
This longitudinal study suggests that TMJ may function well even if signal intensity in the PDA is high. Therefore, we consider that the decreased signal in the PDA seen on T1-weighted images has no appreciable clinical significance.

View full abstract

The objective of this study was to evaluate the effect of mouth opening exercise and self-reduction manipulation on the habitual luxation of the temporomandibular joint (TMJ), which is extremely difficult or impossible to reduce by oneself. Ten patients with habitual luxation of TMJ were enrolled and underwent these procedures. One month later, in all cases there was no recurrence of habitual luxation and the maximum mouth opening without pain to the predicted mouth opening increased significantly compared with that at the first visit. After self-reduction manipulation, the patients had no fear of the luxation at all, and we did not identify TMJ sound by palpation under observation. We suggest that mouth-opening exercise and self-reduction manipulation might be indicated as initial measures for patients with habitual luxation of TMJ.

View full abstract

Purpose: According to recent biochemical studies on synovial fluids, TMJ symptoms are due to inflammation within the structure itself. There are a variety of ways of managing the disorders, and arthrocentesis is one of the effective treatments for closed lock. The purpose of this study was to evaluate the efficacy of combination therapy of two consecutive arthrocenteses for closed lock and to compare the therapy with or without mouth opening exercise.
Subjects and Methods: Subjects were selected from a series of new closed lock patients who visited Aichi-Gakuin University Hospital between November, 1999 and December, 2001. Seventy patients were confirmed as closed lock with MRI and were divided into two groups, those with or without mouth opening exercise. The patients then underwent two consecutive arthrocenteses at a 2-week interval and were followed up every 2 weeks for 12 weeks. The NSAIDs administration with or without mouth opening exercise was continued daily until the patients' symptoms improved. Improvement rate was calculated as a percentage of improved cases among the subjects in each group.
Results: The improvement rate was 76% with mouth opening exercise and 64% without the exercise at follow-up 12 weeks later. Range of motion significantly increased at 4 weeks in the group with mouth opening exercise.
Conclusion: Two consecutive arthrocenteses with NSAIDs administration and mouth opening exercise are effective as a primary treatment for closed lock. The combination therapy with exercise would achieve sufficient range of motion in a shorter period of treatment time than that without exercise.

View full abstract