Background: Magnetic resonance imaging (MRI) is the main imaging modality in the diagnosis of temporomandibular disorders. Furthermore, sagittal cuts are the chief plane in diagnosis of these disorders.
Aim of the study: This study aimed to investigate the validity of para-sagittal cuts taken parallel to lateral pterygoid muscle in depicting the structures of temporomandibular joint.
Subjects and Methods: Twenty symptomatic temporomandibular joint (TMJ) patients performed MRI bilaterally using the traditional para-sagittal cuts and another plane parallel to lateral pterygoid muscle. Four-point scale was used to assess the clarity of articular disc position, disc morphology, cortical bone, and overall quality of the images of both investigated techniques in closed and open positions. Moreover, the final diagnosis of the cases was obtained in each technique.
Results: The mean and standard deviation of muscular aligned cuts in clarity of revealing disc position, disc position, cortical bone, and overall image quality in closed position were 2.83 ± 0.39, 2.63± 0.49, 2.53± 0.51, and 2.83± 0.39, respectively, while those for traditional plane were 2.55± 0.50, 2.43± 0.50, 2.80± 0.41, and 2.53± 0.51 with the same order. In open position, the same investigated points got 2.80± 0.41, 2.73± 0.45, 2.73± 0.45, and 2.80± 0.41 in muscular aligned images and 2.78± 0.42, 2.65± 0.48, 2.82± 0.39, and 2.78± 0.42 in the traditional plane. Both techniques provided the same diagnosis in 97.5% of the cases.
Conclusion: Parasagittal magnetic resonance images taken parallel to lateral pterygoid muscle deposited higher image quality than the traditional plane in revealing temporomandibular structures.