Magnetic resonance imaging of temporomandibular joint with anterior disk dislocation without reposition - long-term results.

Objectives: Anterior disk dislocation (ADD) without reposition in the temporomandibular joint (TMJ) may be associated with morphological changes in the retrodiscal region of the bilaminar zone presenting as pseudo-disk (PD). The present study was initiated to investigate the development of retrodiscal fibrosis in a period of 4-8 years and to assess if patients with a PD show differences in the clinical and radiologic findings versus patients without a PD.

Materials And Methods: In a retrospective follow-up study of 33 consecutive patients with ADD without reposition in one or both TMJs, a clinical and MRI-supported evaluation was conducted 4 to 8 years after baseline diagnosis.

Results: In 45 % of the TMJs with ADD without reposition, a PD could be identified. Twenty-one of 31 patients who showed pain at the baseline examination (VAS mean 56 ± 38) were pain free. The mouth opening capacity (MO) of the mandible could be increased in 80 %. There were no statistical significant differences between patients with or without PD in these clinical features. The MRI parameters effusion and translation showed a statistical tendency for more improvement in the group with PD (p = 0.061, 0.064).

Conclusion: In about half of the patients, a structure corresponding to a pseudo-disk developed during follow-up. Pain and the mouth opening capacity improved in all patients independent of the development of a PD.

Clinical Relevance: Detection of a PD during follow-up of patients with ADD without spontaneous reposition does neither predict favorable nor worse therapy response and clinical course.