Modified Temporomandibular Joint Disc Repositioning With Mini-screw Anchor: Part II—Stability Evaluation by Magnetic Resonance Imaging

Purpose: The purpose of this study was to evaluate the stability of disc position and condylar status by magnetic resonance imaging (MRI) after temporomandibular joint (TMJ) disc repositioning surgery with a mini-screw anchor technique. Materials and Methods: Patients diagnosed with anterior disc displacement (ADD) and operated on for disc repositioning from 2010 through 2016 were included in the study. MRI scans within 1 week after operation (T1) and during at least 1-year follow-up were used to evaluate changes in disc position and condylar bone. During follow-up, ADD without reduction was considered relapse and the bone status was classified as regeneration or degeneration. Results: One hundred seven patients with 149 joints were included in the study. Postoperative MRI scans (T1) showed that all discs were repositioned. During an average 23.40-month follow-up (range, 12 to 84 months), 95.3% of discs (142 of 149) were still in position, whereas 4.7% of discs (7 of 149) had relapsed anteriorly. New condylar bone formation was observed in 74.50% of joints (111 of 149), no bone change was observed in 23.49% of joints (35 of 149), and bone resorption was observed in 2.01% of joints (3 of 149). Conclusions: TMJ disc repositioning by a mini-screw anchor provides stability for treatment of ADD. Disc repositioning also can stimulate condylar bone regeneration.