Adolescent TMJ tomography and magnetic resonance imaging: a comparative analysis

Area of Science:

• Dentistry
• Radiology
• Orthodontics

Background:

• Temporomandibular joint (TMJ) disorders are common, with internal derangement being a significant issue.
• Accurate diagnosis of TMJ internal derangement is crucial for effective treatment planning.
• Radiographic tomography has been used to assess TMJ soft-tissue status, but its diagnostic accuracy requires further evaluation.

Purpose of the Study:

• To assess the predictive value of radiographic tomography compared to magnetic resonance imaging (MRI) for diagnosing TMJ soft-tissue status.
• To evaluate the accuracy of tomography in identifying abnormal disc position in adolescent TMJs.

Main Methods:

• Eighty-two TMJs from 41 subjects (mean age 12.5 years) were independently evaluated using axially corrected tomography and MRI.
• Statistical tests were performed to compare and correlate the classifications from both imaging modalities.
• Sensitivity, specificity, and predictive values of tomography were calculated against MRI as the gold standard.

Main Results:

• A significant relationship (P < .05) was found between tomographic and MRI classifications of disc position: nondisplacement (55%), reducing internal derangement (35%), and nonreducing internal derangement (10%).
• Tomography demonstrated a sensitivity of 0.43, specificity of 0.80, positive predictive value of 0.64, and negative predictive value of 0.63 for detecting abnormal disc position.
• These values indicate limited accuracy of tomography in diagnosing TMJ internal derangement.

Conclusions:

• Radiographic tomography is inappropriate as a diagnostic test for TMJ internal derangement.
• Magnetic resonance imaging is a more definitive and accurate method for evaluating TMJ soft-tissue status and disc displacement.
• Adolescent TMJ assessment for internal derangement should prioritize MRI over conventional tomography.