 RME corrects the morphological constriction of the upper arch caused by buccal breathing and also reduce the airway resistance. Despite reports of RME influencing volume enhancement in pharyngeal airway, there are still few three-dimensional studies following the post-expansion effects. In addition, these changes are doubtful due postural changes of the tongue during the tomography exam. Conflicts of results are also present for changes in the nasal septum of children. The main alteration mentioned is the increase in the length of the lower third of the septum. 