Magnetic resonance image findings on reposition articular disc at opened mouth after treatment

Cases of disc position changes from anterior disc displacement without reduction to with reduction

Abstract

Objective: We evaluated alteration of the articular disc position at opened mouth after treatment by magnetic resonance imaging findings in patients with temporomandibular joint disease with anterior disc displacement without reduction.
Material and methods: Our study based on 11 joints found that the disc changed from anterior disc displacement without reduction at the initial MRI study to anterior disc displacement with reduction at follow-up MRI study. All of the study subjects were female, with age ranging from 15 to 36 years. One joint underwent interventional radiology (lyses and lavage) and splint therapy, 3 joints underwent pumping manipulation and splint therapy. Three joints underwent splint therapy and 1 joint received only follow-up. Four joints underwent splint therapy after the interventional radiology on the contralateral side. Clinical evaluation focused on temporomandibular pain, joint sound and trismus. MR imaging was performed for the mandibular head position, configuration of articular disc and degree of disc displacement at closed mouth.
Results: Clinical signs observed with alteration of the disc position were disappearance of TMJ pain in 7/9 joints (77.7%), disappearance of TMJ sound in 1/5 joints (20%) and appearance of sound in 3/6 joints (50%). An increase in the distance of opening the mouth was found in all of the 7 joints with trismus. The changes in the MR image findings were mandibular head position changes in 2/11 joints (18.1%), disc configuration in 3/11 joints (27.2%) and degree of displacement in 5/11 joints (45.4%). In the mouth closed position, the mandibular head moved antero-inferiorly after treatment.
Conclusion: It is possible that the articular disc was repositioned at the mouth opening after treatment in the case of younger patients with a few disc deformities of anterior disc displacement without reduction.