In High-Palate (RPE) Hyrax Appliance, the expansion screw is positioned high in the palate for greater comfort. Bands are placed on the first molars. Rests are bonded to the occlusal surface of the primary molars, thus eliminating the path of insertion problem that occurs when four bands are used.

Extra heavy support wires are also employed to prevent the appliance from flexing as pressure is applied. If you find that a posterior crossbite is locked due to a deep bite or tight intercuspation, it is recommended that a lower occlusal splint be placed temporarily to expedite treatment without affecting the mandibular dentition.