3 王鈴鈞 / Ling-Chun Wang
Main Instructor Yu-Jen Chang
Department / Institution Orthodontic Department, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Kaohsiung, Taiwan
Classification Research report
The aim of this research is to clarify the post-surgical stability of temporomandibular joints (TMJs) in skeletal Class III patients treated with 2-jaw orthognathic surgery performed with 3-dimension (3D) computer-aided simulation and navigation (CASNOS) protocol.
23 nongrowing skeletal Class III patients with mandibular prognathism and maxillary retrognathism treated with 2-jaw orthognathic surgery were enrolled. The surgery was planned according to the protocol of CASNOS. Computed tomography scans were performed in all patients 3-week pre-surgically and 6-month post-surgically. 3D facial skeletal images were reconstructed, segmented and superimposed in the software. Amount of displacement of the most medial and lateral points of the condyles as well as the change of intercondylar angles were measured in the software to evaluate the post-surgical stability of TMJ.
The mean displacement of the right most lateral condylar point was 1.04 ± 0.42 mm and the mean displacement of the left most lateral condylar point was 1.19 ± 0.41 mm. The mean displacement of the right most medial condylar point was 1.03 ± 0.39 mm and the left most medial condylar point was 0.96 ± 0.39 mm. The mean intercondylar angle was 161.61 ± 5.08° pre-surgically and 159.28 ± 4.92° post-surgically.
All the landmarks displacement of the condyles after the surgery were within a range of 1.2 mm. This indicates the bimaxillary orthognathic surgery via 3D CASNOS protocol can achieve a desired and stable result of TMJ position in treating skeletal Class III adult patients with retrognathic maxilla and prognathic mandible.
Post-surgical Stability of Temporomandibular Joint of Skeletal Class III Patients Treated with 2-jaw Orthognathic Surgery via Computer-Aided Simulation and Navigation (CASNOS)