Ideally, the upper jaw should be wide enough so the upper teeth sit outside of the lower teeth. If the upper jaw is narrow, then the upper teeth may sit directly on top of the lower teeth or they may sit inside of the lower teeth which is called a cross-bite. Sometimes a cross-bite can be improved with braces but if the narrowness is significant, then it may be necessary to widen the maxilla (upper jaw) bone. This can be accomplished with an orthodontic appliance called a Rapid Palatal Expander (RPE).
The RPE is a custom-made appliance which mounts with bands around the upper permanent molars. The RPE goes across the palate but does not touch the palate. In our office the RPE is a fixed appliance, not removable. The RPE has a small screw in the center. The screw is turned as instructed at home by the patient or parent with a key. Turning the screw puts gentle pressure on each side causing the maxilla to gradually and gently expand in width.
The RPE improves crowding by creating a wider arch for the teeth to sit in. With adequate space, the teeth can erupt in more ideal positions. A wider arch allows space for the tongue to rest in a proper position. The RPE improves the fit of the upper jaw to the lower jaw. When the jaws fit together properly it encourages them to grow more normally. The roof of the mouth is also the floor of the nose so widening the upper jaw improves the airway. Correcting a narrow palate while a patient is young eliminates the need for surgical correction as an adult to resolve this problem. Also, it improves aesthetics by widening the smile.
If a cross-bite is left untreated, it can lead to lopsided jaw growth, recession of the gum tissue, abnormal wearing of the enamel surface of the tooth (teeth), and TMJ problems. If a narrow maxilla is not treated while the bones are still growing then surgery becomes necessary to correct this problem.
While a patient is young, widening the maxilla can be accomplished easily with a Rapid Palatal Expander. Before growth is over, the maxilla has a soft suture in the center. Gentle pressure from the RPE allows the soft suture to separate and the bone to widen. The palate can be widened up to 11mm at a time (that’s a lot!). It’s fast; all of the widening occurs in just 4 weeks! The appliance then remains in place for another 3-4 months to allow the bone to heal. It’s preventative; once growth is over, widening the palate becomes a surgical event.
If your child needs orthodontic treatment, please contact our office to schedule an appointment. We are happy to provide a free initial consultation.