[Rapid maxillary expansion: presentation of 3 clinical cases]

The use of rapid palatal expansion (RPE) escalates greatly in routine clinical practice. The most commonly recognized indication for rapid palatal expansion is the correction of a posterior crossbite. RPE is produced by applying a lateral force against the posterior maxillary dentition, producing a separation of the midpalatal suture and its remodeling. The clinical consequence of such a change is an increase in total arch length. That will allow the accommodation of impacted, rotated or displaced teeth into the dental arch. This additional arch length may lead to an overall reduction in the number of patients who undergo extraction due to tooth size-arch size discrepancies. RPE also can be used for preparation for functional jaw orthopedics or orthognathic surgery. Generally, RPE appliances are fixed and there are two types of expanders: the Haas-type and the Hyrax-type rapid palatal expanders. This clinical article presents three cases of rapid palatal expansion and their results.