This is a report about the orthodontic treatment of a 13-year, 10-month-old boy with total ankyloglossia combined with a Class III occlusion. The patient’s tongue was fixed to the floor of his mouth and could not be elevated at all. He had a maxillary deficiency and a mandibular protrusion with a negative overjet. However, he was able to retrude his mandible to an edge-to-edge position. Before orthodontic treatment, the ankyloglossia was surgically rectified. Orthodontic treatment was initiated to improve the patient’s occlusion and facial appearance by correcting his retruded maxilla by means of a face mask, fixed appliances, and Class III elastics. This led to a functional occlusion and an acceptable facial appearance. World J Orthod 2010;11:278–283.

Key words: ankyloglossia, Class III occlusion, face mask, maxillary deficiency, tongue dysfunction