The Rapid Maxillary Expansion Appliance is used to orthopedically widen the upper dental arch when it is too narrow in relation to the lower jaw.
The appliance for Rapid Maxillary Expansion (RME) is constructed with a palatal expansion screw whose metal arms are soldered to a wire framework. The framework can be supported by bands on the molar teeth, glued directly to the teeth or supported on the bone.
In younger patients the two halves of the upper jaw have not yet fused and new bone is laid down between the halves during expansion. The upper jaw then remains permanently wider. This appliance can be used on children as early as 8 years of age.
In older patients, where the two halves of the maxilla have fused, the expander is normally used in conjunction with a surgical procedure to remobilize the two halves. This is known as a Surgically Assisted Rapid Palatal Expander.