Patients with severe alterations of the maxillary growth pattern, due to long term predominant oral respiration, primarily need orthopaedic appliances, rather than common orthodontic mechanics. In cases of maxillary transversal deficiency, rapid expansion is indicated to recover an adequate width. Such treatment improves the ability for nasal ventilation. When the maxilla is sagittally underdeveloped, a facial mask is used to protract the entire maxilla. Other ways of treatment include oral screens, partial glossectomy, myofunctional therapy and respiratory gymnastics. Finally orthodontic treatment can be planned to correct irregularities of the teeth and residual malocclusions.