Rapid Palatal Expansion with the Keles Keyless Expander.

Rapid palatal expansion (RPE) is commonly used in orthodontic treatment to correct maxillary transverse deficiency, increase arch length, indirectly widen the mandibular arch in some cases, and move the maxilla downward and forward.(1-5) Maxillary transverse deficiency is usually accompanied by posterior crossbite, unless there is constriction or lingual tipping of the mandibular teeth. Posterior crossbite occurs in about 7.1% of American children in the mixed dentition, and it usually does not self-correct as the patient transitions into the permanent dentition.(6) The Keles Keyless Expander(*) (KKE) offers an efficient new method to address the maxillary transverse deficiency issue.