Two-Phase Orthodontic Treatment in Class II Division 1 Malocclusion

A two-phase treatment comprising functional orthopedic therapy and fixed orthodontic therapy is oftenproposed for pubescent patients with Class II division 1 malocclusion. Mandibular retrognathism is a morecommon underlying cause of Class II skeletal discrepancy than the maxillary prognathism. In such cases, anactivator is a widely used functional orthopedic appliances to enhance the mandibular growth. After resolvingthe sagittal problem by using the functional appliances, the biomechanical considerations of the anchoragerequirement could be simplified in the second phase fixed appliance therapy, and the total treatment durationcould be shorter. This case report describes a two-phase orthodontic treatment of an 11-year-old boy withClass II division 1 malocclusion which characterized as mandibular retrognathism. The patient was correctedwith an activator to improve the skeletal relation. Subsequently, fixed orthodontic appliances were used forfull mouth dental alignment and occlusion. After treatment, the patient exhibited Class I molar relationships,proper occlusion, and harmonized facial esthetics. (Taiwanese Journal of Orthodontics. 30(1): 18-30,2018).