Abstract
A 17-year-old boy had a skeletal Class III malocclusion with facial asymmetry, a unilateral posterior crossbite and functional shift of the mandible to the left on closure. There was bilateral constriction of the maxilla and crowding in both of the arches. The patient was treated orthodontically with an edgewise appliance and a bonded Hyrax for maxillary expansion. The result of the orthodontic treatment was facial symmetry and optimal occlusion. At the one year follow-up, the condition had been maintained.