Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 7 3 2020 12 26 158 164 Amir Hosein Mirhashemi Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Sadegh Akhoundi Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Hannaneh Ghadirian Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Alireza Parhiz Department of Oral and Maxillofacial Surgery, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Rashin Bahrami Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Seyyed Morteza Samimi Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. 2020 06 25 2020 07 14 The purpose of Dentofacial Deformity Treatment is to achieve the proper aesthetic and functional occlusion results. Conventional orthognathic surgery involves a long-term orthodontic phase before surgery for about 18 months, in which patients’ facial appearance worsens and their motivation decreases. In the SFA (surgery first approach) method, the surgery is performed before orthodontics and orthodontic therapy is performed to improve dental occlusion and final settlement. Two main advantages of this method are the reduction of the therapy period and the initial improvement in the patient’s facial appearance. The SFA has certain benefits, especially in Class 3 malocclusion. In this case report, a 19-year-old girl with a relatively severe Class 3 malocclusion with skeletal discrepancy due to a mandibular prognathism and maxillary retrognathism, and asymmetrical face with chin deviation to left is presented with a unilateral posterior cross bite which was effectively treated using the SFA protocol. The SFA therapy was performed by removing orthodontics before surgery, followed by maxillary advancement surgery, and posterior maxillary impaction and postoperative orthodontic sets to dental alignment and settling the occlusion. Despite the overall reduction in the orthodontic therapy period to less than 9 months, good results and functional occlusion were obtained. Keywords: Surgery first; Orthognathic surgery; Skeletal class III; Malocclusion; Orthodontic treatment. https://jcr.tums.ac.ir/index.php/jcr/article/view/330 https://jcr.tums.ac.ir/index.php/jcr/article/download/330/305