Background: Temporo-mandibular joint dysfunction [TMD] is a common condition affecting many adults. To diagnose TMD, physicians commonly use traditional Magnetic Resonance Imaging [MRI] scans of the jaw in multiple fixed positions - both with the mouth closed and open. Nowadays, several fast pulse sequences have been proposed for dynamic MRI by some investigators.
The Aim of the work: This study aims at evaluating the correlation between dynamic and static MRI sequences as diagnostic tools to diagnose temporomandibular joint dysfunction and their ability for diagnosis of the different types of displacement.
Patients and Methods: A prospective study included 40 patients with TMD dysfunction. Static and dynamic MRI studies were compared for different pathological findings.
Results: On comparing static and dynamic studies for various findings, for articular disc detection, dynamic MRI was good for detecting the disc in only 17 [42.5%] versus 30 [75%] by static MRI [P=0.038]. Regarding condylar translation, there was significant difference between the studied techniques as dynamic MRI identified 8 [20%] cases as hypermobile, 14 [35%] as hypomobile in contrast to 1 [2.5%] and 13 [32.5%] cases by static MRI [P=0.001]. Regarding condylar head detection, dynamic MRI was good for its detection in only 30 [75%] versus 37 [92.5%] by static MRI [P=0.012].
Conclusion: Using dynamic MRI, it is possible to observe the articular disc throughout the entire process of opening and closing the jaw, as well as the movements associated with internal derangement and the assessment of the relationship between the disc and the condyle. This method was faster than static MRI. However, there were some discrepancies between the two techniques, and dynamic sequences cannot replace static sequences when evaluating internal derangement disorders of the temporomandibular joint [TMJ], but can be used in conjunction with them.