Effect of arthrocentesis and hydraulic distension on the temporomandibular joint disk position.

OBJECTIVE: Recent studies have suggested arthrocentesis and hydraulic distension as an effective treatment modality in patients demonstrating clinical findings consistent with the diagnosis of disk displacement without reduction, normal range of motion thereby being restored and pain of the temporomandibular joint reduced. In view of the fact that only a few studies have been performed to verify the biologic concept of disk displacement without reduction as a diagnostic and therapeutic approach in patients with "closed-lock" symptoms, the purpose of this study was to investigate whether temporomandibular joint-related variable disk position might be linked to cessation of related signs and symptoms associated with the performance of arthrocentesis and hydraulic distension.

STUDY DESIGN: The study compared 15 patients, each of whom was assigned a clinical unilateral temporomandibular joint-related diagnosis of internal derangement (ID) type III (disk displacement without reduction) in combination with capsulitis/synovitis. Clinical diagnoses were made according to the Clinical Diagnostic Criteria for Temporomandibular Disorders. Bilateral sagittal and coronal magnetic resonance images were obtained immediately preoperatively and at 2-month follow-up to establish the presence or absence of associated types of ID. Temporomandibular joint-related pain, level of function, and mandibular range of motion were assessed preoperatively and the data were compared with the respective 2-month follow-up findings.

RESULTS: Comparison of the pretreatment temporomandibular joint side-related data revealed the temporomandibular joint side with an ID-III in combination with capsulitis/synovitis to be associated with significantly more magnetic resonance imaging diagnoses of ID than of an absence of ID (P <.001) and with significantly more disk displacement without reduction than disk displacement with reduction (P <.001). At the 2-month follow-up, clinical evaluation showed a significant reduction in temporomandibular joint-related pain during function (P <.001), a significant reduction in the prevalence of temporomandibular joint-related diagnoses of capsulitis/synovitis (P <.001) and ID-III (P <.01), and a significant increase in mandibular range of motion (P <.01). There was no change in the prevalence rates of associated temporomandibular joint side-related IDs.

CONCLUSIONS: The results confirm the concept of disk displacement as a diagnostic approach but not as a therapeutic approach for patients presenting with signs and symptoms of unilateral ID-III in combination with capsulitis/synovitis. In terms of clinical decision-making in temporomandibular disorder-related instances of ID, magnetic resonance imaging may be used as a diagnostic method for identifying the diagnostic validity of the variable "disk-condyle relationship."