Objectives: To test the feasibility of the application of 3D planning software in the severe deformities with hemimandibular hyperplasia.

Methods and materials: 13 consecutive patients from the department of Oral and Maxillofacial Surgery (Shanghai Ninth People’s Hospital) were included. The values of ECT of the affected condyles in the patients were all over 0.1. Preoperative three-dimensional planning including segmentation, osteotomies and movements of the jawbones were simulated using the software as well as the condylectomy. The surgical wafers for bi-maxillary orthognathic surgery and the osteotomy guide for mandibular inferior border trimming were fabricated by laser sintering based on the simulating surgical data. During the surgery, the Le Fort I osteotomy was performed followed by endoscope-assisted intraoral condylectomy in the affected side and the sagittal split for the other side. The virtual wafers provided as a reference for bone segments reposition and fixation. The mandibular inferior border osteotomy guide provided a reference for trimming the inferior border of the affected mandible to gain the asymmetry of the mandible.

Results: All the procedures for the 13 patients went smoothly in the operating room. The facial symmetry and occlusion were satisfied in all cases in the follow-ups. The pathology turned out to be condylar osteochondroma in 8 cases and condylar hyperplasia in 5 cases.

Conclusions: The 3D virtual planning software provides a good aid for precise simulating orthognathic surgery in the complicated cases with severe asymmetric deformities. The endoscope provides more safety and better visualization for the intraoral condylectomy.

Conflict of interest: None declared.