Resumo (EN)
Rapid maxillary expansion (RME) has always draw great interest of researchers in the orthopedic field along the years. lt's a largely employed procedure and maxillary constriction is often associated with malocclusions. ln addition, maxillary constriction has an early development and is hardly corrected. The aim of this study is to assess the magnitude of the expansive force during RME in the different dentitions phases. The sample consisted of 9 Brazilian patients, 8 female and 1 male, who were sorted in three groups: Group 1, three patients with deciduous dentition, Group li, three patients mixed dentition and Group Ili, three patients with young permanent dentitions. The appliance utilized in this study was a palatal expansor with an acrylic splint for the supporting teeth. Curves representing the forces applied during RME in the protocol of two daily activations were evaluated. They showed that the way such expansive forces behave along the procedure had a longitudinal and individual variation, including between the experimental groups. lt was also determined that the maximum expanding force measured in Group I was 20N, in the Group li was 65N and in Group Ili was 78N.
