The Angle Class II division 1 malocclusion is often accompanied by maxillary transverse deficiency. When ever is possible, this maxillary transverse problem must be corrected before the anteroposterior correction. The rapid maxillary expanders is the appliance more used to correct the transverse deficiency. For the Class II malocclusion correction the fixed functional appliances are more studied and used. They are a kind of intraoral appliance that almost don't need patient's collaboration. The aim of this study is to show the results' stability after six years of the orthodontic treatment with Hyrax expander, followed by Herbst and straight wire appliances. After a literature review, a clinical case with maxillary transverse deficiency and Class II division 1 malocclusion treated with this therapy is reported. The treatment duration was very brief and the results were functionally and esthetically satisfactory with a long-term stability.
Malocclusion; Angle Class II; Orthodontics; Palatal expansion technique
