Among all the aspects studied, it is noteworthy that 31.2% of patients evaluated were children with speech disorders who were older than five years, an age when the phonological system must be fully developed, suggesting that mouth breathing may be an interfering factor in its development. However, dental occlusion, which was not considered in the present study, may have an important association with speech disorders, as observed by Farronato et al. The presence of Angle class III malocclusion, diastema, increased overjet, and presence of open bite or deep bite tend to be associated with speech disorders.