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Stability of the contralateral temporomandibular joint disk position after disk repositioning on one side
Chuan Lu1, Jieyun Zhao2, Changbin Zhang3
1Attending, Department of Oral Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine; Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology; National Clinical Research Center of Stomatology. No. 639 Zhi Zao Ju Road, Huang Pu District, Shanghai, 200011, China.
Objective:
To evaluate the stability of the contralateral temporomandibular joint disk position after disk repositioning on 1 side.
Study Design:
Patients with unilateral anterior disk displacement (ADD) treated by disk repositioning from 2015 to 2019 were included in the study. The contralateral disk status was classified as follows: normal, ADD with reduction (ADDwR), and medial/lateral displacement. At 1-year follow-up, changes in the contralateral disk position were evaluated by MRI.
Results:
Two hundred thirty-four patients were included in the study. There were 84 disks with normal position, 51 with ADDwR, and 99 with medial/lateral displacement (M/LD) in the contralateral joint. At 1-year follow-up, all the repositioned disks were stable without relapse. In the contralateral joints, 75% of the disks with normal position were unchanged compared with 43.1% of the ADDwR and 54.5% of the M/LD. ADDwR had the highest rate of changing to ADDwoR compared with the disks in normal position (4.8%) and M/LD (7.1%, χ2 = 16.13, P < .001). There were 28.3% of M/LD disks and 3.9% of ADDwR that changed to normal position.
Conclusions:
After unilateral disk repositioning, most of the contralateral disks with normal position were stable. M/LD disks tended to move to normal position, whereas ADDwR was largely changed to ADDwoR.
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