ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of orthodontic treatment on temporomandibular joint (TMJ) in adult low-angle patients with skeletal class III malocclusion.</p><p><b>METHODS</b>Sixteen adult female low-angle patients with skeletal class III malocclusion were included in the study. All patients were treated with OPA-K straight wire technique. Lateral cephalometric and corrected transcranial projection films were taken before and after treatment. Cephalometric analysis was carried out. All data were analyzed statistically.</p><p><b>RESULTS</b>After orthodontic treatment, the linear measurement and area of anterior space in TMJ increased by 0.27 mm (P < 0.001) and 0.70 mm(2) (P < 0.01), respectively, while the posterior space decreased by 0.24 mm and 0.67 mm(2), respectively (P < 0.001). Linear ratio decreased from 22.13% to 9.64% (P < 0.001), and area proportion decreased from 1.56 to 1.19 (P < 0.01). Anterior space became equal to the posterior space. Cephalometric analysis showed that point Co, Ar, Go and Pg were all retruded (P < 0.05).</p><p><b>CONCLUSIONS</b>After orthodontic therapy, the condyle moved posteriorly to normal concentric position, which would be helpful in alleviating temporomandibular disorders (TMD) symptom in adult low-angle patients with skeletal class III malocclusion.</p>