Efficacy of Arthroscopic Discopexy on Condylar Growth in Temporomandibular Joint Anterior Disc Displacement: A Randomized Clinical Trial

Background: Adolescents with temporomandibular joint (TMJ) anterior disc displacement (ADD) frequently develop dentofacial deformities. It is unknown if adjunctive arthroscopic discopexy compared to orthodontic treatment alone increases condylar growth and then improves dentofacial deformity. This study aimed to determine whether arthroscopic discopexy before functional appliance (joint-occlusal treatment) or single functional appliance (occlusal treatment) increases condylar growth and improves dentofacial deformity among adolescents with TMJ ADD. Methods: A multicenter, randomized, parallel controlled trial was conducted in three centers in China. Adolescents diagnosed with TMJ ADD and dentofacial deformity were enrolled. Eligible participants were randomly assigned to a joint-occlusal group or occlusal group at a ratio of 2:1. MRI, cephalometric radiographs were evaluated at baseline, 8 months and 14 months. The primary outcome was changes in condylar height from 14 months to baseline. Secondary outcomes were changes in skeletal position. Results: A total of 240 patients (14.65±1.88 years of age) were randomized (joint-occlusal group: 160; occlusal group: 80). The overall difference in condylar height between groups was 3.65 mm (95% CI, 3.10 to 4.19; p < 0.001). The between-group differences in condylar height on the left and right sides were 3.60 mm (95% CI, 2.92 to 4.28; p < 0.001) and 3.69 mm (95% CI, 3.06 to 4.32; p < 0.001), respectively. Significant between-group differences were noted in skeletal position (all p < 0.001). Conclusions: Joint-occlusal treatment can promote condylar growth and improve dentofacial deformity in adolescents after 14 months when compared with single occlusal treatment.