Nonsurgical treatment of adult skeletal Class III malocclusion with crowding and missing four premolars corrected with extraction of mandibular first molars

An adult male patient was present with anterior cross bite. He was referred to Orthodontic Clinic of Niigata University Medical and Dental Hospital for recommendation of surgical orthodontic treatment by general practitioner. The patient was diagnosed as skeletal Class III with anterior crowding and missing four premolars. To correct anterior cross bite and crowding, surgical orthodontic treatment was considered, but the patient refused orthognathic surgery. We therefore determined that nonsurgical treatment with mandibular bilateral first molar extraction would be indicated.After treatment, suitable overjet, overbite and proper functional occlusion were attained with Class I molar relation. Active treatment was 34 months, and the treatment result remained stable 2 years and 4 months after debonding.