Aim: The aim of this study was to determine the value of dynamic high-resolution ultrasonography (HR-US) in the evaluation of internal derangements of a temporomandibular joint (TMJ) in the open and closed mouth position.
Settings and design: The study designed to collect the sample from the Outpatient Department of Oral Medicine and Radiology at GDC, Bangalore. Patients with pain, clicking, deviation, and tenderness were included in the study as a symptomatic group. The asymptomatic group was free of any symptoms.
Materials and methods: Maximum mandibular range of motion (Open and Closed) was performed during HR-US of TMJ in 100 consecutive patients, (50 symptomatic and 50 asymptomatic cases, a total of 400 joints, with 200 joints in the right and left closed and open mouth position;36 males and 64 females; age range, 16-50 years; mean age 27.56 years). Subsequently, the entire group, after clinical diagnosis, went for HR-US. Sonography confirmed the diagnosis by showing internal derangement in 34 (68%) of the symptomatic group and the remaining 16 (32%) patients failed to show any derangement. In the asymptomatic group 40 patients did not show any pathology associated with TMJ, whereas, 10 patients showed internal derangement. The data obtained was analyzed statistically.
Results: HR-US performed during the maximal range of motion (Open and Closed) helped to detect 34 instances (68 joints) of internal derangement, which were true positive cases, whereas, 16 patients (32 joints) showed a false positive finding for internal derangement (ID). The results obtained showed a sensitivity of 64%, specificity of 88%, positive predictive value of 84%, and a negative predictive value of 71%, with an accuracy of 76%.
Conclusions: Dynamic HR-US being non-invasive can provide valuable information about internal derangement of the TMJ in mandibular closed mouth than open mouth position.