ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the positions and forms of temporomandibular joints (TMJ) with different vertical skeletal patterns in Class II division 1 patients.</p><p><b>METHODS</b>Cone- beam CT scans of 117 Class II division 1 adolescent patients (including 30 patients with high angle, 58 with average angle and 29 with low angle) were selected and reconstructed using Mimics 10.0 software. Fourteen measurements related to the positions and forms of condyle, forms of fossa and joint spaces were performed.</p><p><b>RESULTS</b>Compared with high and average angle patients, the condyles in low angle patients located more posteriorly and inferiorly [the vertical distances between condyle and S was (20.67 ± 1.99)mm and the antero-posterior distances between condyle and S was (9.15 ± 1.61)mm]. The joint fossae were deeper [the fosse depths was (7.83 ± 1.06)mm]. The angles of posterior joint node bevels were bigger [the inclinations were (28.91 ± 3.94)° ]. The condyles were shorter, thicker, tipped more anteriorly and positioned more posteriorly [the proportions of post-positioned condyles of low angle, average angle and high angle patients were 26%, 4%, 0% respectively].</p><p><b>CONCLUSIONS</b>Class II division 1 adolescents with different vertical skeletal patterns had different forms of fossae, and different positions and forms of condyles.</p>
