Purpose: The correction of mandibular deformity in Treacher Collins syndrome can be difficult. The aims of surgery are both aesthetic and functional. Conventional orthognathic surgery and distraction osteogenesis are two current surgical options. This study presents long term dental and aesthetic results obtained with a one stage orthognathic procedure.

Materials and methods: We conducted a retrospective study on 11 patients presenting with Treacher Collins mandibular deformity. They were classified according to the Pruzansky–Kaban assessment and treated with conventional orthognathic surgery. We compared the facial aesthetics improvement and the long term stability of the occlusion to data from the literature.

Results: Our surgery protocol allowed significant movements of the mandible, resulting in dramatic and instantaneous improvement of facial appearance and dental occlusion. Skeletal and dental stability was complete after one year post surgery.

Discussion: Conventional orthognathic surgery should be considered in the treatment of mandibular hypoplasia in Treacher Collins syndrome. The Pruzansky–Kaban radiological classification remains of great interest for choosing the most suitable surgical technique. This classification can be refined using relevant clinical and radiological findings in order to help the surgeon obtain immediate optimal occlusion and good aesthetic results.