Objective：To study the clinical treatment of severe dental ankylosis by orthognathic-orthodontic treatment. Methods：A total of 2 patients suffering from severe dental ankylosis together with maxillofacial discrepancy were operated by a special orthognathic-or－thodontic treatment based on their individual characteristics. Results：All the surgeries were performed as planned with stable long term effects. Dento-maxillofacial deformities were corrected and the masticatory function was improved. All patients were satisfied with the results. Conclusion：For patients with severe dental ankylosis，the individualized treatment should be made based on actual situation of each patient. In this study，a variety of improved orthognathic-orthodontic treatment approaches including unconventional mandibu－lar subapical osteotomy and ‘sandwich’ onlay bone grafting were used with a satisfactory clinical effect and minimal complications，making this surgery valuable for clinical application.