The transversal expansion of maxilla in order to treat maxillary constriction has been used in orthodontic area for centuries. The transversal expansion of maxilla occurs by both the opening of maxiller suture and dental lateral tipping of teeth. For the expansion purposes of maxilla besides the simple wire appliances ,like quad-helix, very complicated appliances are also used. The purpose of this study is to evaluate the dental and skeletal effects of Compound Palatal A rch including nickel-titanium which can produce consistent, continous and light forces. The material of this study are 11 patients,4 male & 7 female, selected from the clinical intake of Marmara University Orthodontic Department . The patients were selected among those who have maxillary constriction and mild to moderate maxillary crowding. The measurements are done on PA radiographs and orthodontic models taken both before and after expansion. On the models and the PA radiographs the following measurements are performed: intermolar width, inter primary molar width, arch length, arch perimeter, degree of molar tipping and molar rotations. In addition to these parameters the opening of midpalatal suture has also been evaluated by occlusal radiographs taken before and after treatment.

Keywords: Maxillary expansion, Ni-Ti expansion, Palatinal Expansion