Assessment of disc position in clinically diagnosed patients of internal derangement of the temporomandibular joint through MRI

Aims and Objectives: To study the efficacy of MRI in assessing the disk position in clinically diagnosed patients of TMJ, Disk Displacement with Reduction and Disk Displacement without Reduction, and also compare the MRI findings between a control group and patients with Disk Displacement. Materials and Methods: Magnetic Resonance Imaging (MRI) was performed on a total of 16 clinically diagnosed patients of Internal Derangement of the TMJ, 13 of whom were diagnosed with Disk Displacement with Reduction, and the remaining 3 were diagnosed with Disk Displacement without Reduction. 6 asymptomatic volunteers formed the Control Group. The selected patients were then made to undergo an MRI Scan of the TMJ using a 1.5 Tesla MRI Scanner. The MRI scans were evaluated by a radiologist who was unaware of the clinical findings of the patients who were being included in the study. Statistical Analysis Used: Chi square test. Result: Of the total of 3 diagnosed patients of ADDWOR, MRI detected it in 2 cases and thus detection of MRI being 66.7%. Similarly, of the total 13 patients diagnosed with ADDWR, MRI detected it in 10 and thus detection of MRI being 71.4%. Comparing the frequency of detection between the two procedures, χ2 test revealed similar detection between the two procedures (χ2 = 0.03, P =0.870). To test the reliability (reproducibility) of MRI findings, the findings were also performed on 6 controls. Comparing the frequency of MRI findings between the two groups, χ2 test revealed similar visualization in both groups {83.3% (in Control) vs. 70.6% (in patients), χ2 = 0.37, P = 0.541}. Conclusion: There is a high similarity between the Clinical and the Radiological Diagnosis by using MRI as the investigative modality, and thus MRI is considered one of the most efficient modality for assessing the articular disk in Temporomandibular Joints.