Maxillary Palatal Expander (RPE)
These are fixed to the upper molar teeth usually. RPE is used to expand the upper arch when It is either narrow or there is a need for more space. Expansion is completed much faster with this appliance than with the removable version. The upper permanent 1st molars need to be in the mouth for the appliance to be placed therefore limiting its use until after the age of 6years old.