When and Why Do You Need Rapid Palatal Expander (RPE)

There are many dental and orthodontic appliances available to correct oral problems like misaligned teeth, jaw or narrow palate. Some of these procedures work the best when the patient is still young when the bones are soft, growing and easy to manipulate.

One of the common dental appliances used by dentists on growing children is the rapid palatal expander (RPE). It is used to expand the palate and to correct the bite that either has a crossbite (“opposite” bite) or a narrow upper arch. It widens the upper jaw to create space for permanent teeth. RPE is usually worn for six to nine months in order to correct the bite.

The American Academy of Pediatric Dentistry recommends correcting crossbites “as early as possible when behavior allows”, and at Smiles For Kids we can usually do it around 5 years of age. Young children are adaptable and flexible, and the procedure is smooth and easy for them. Since the joint of the upper palate is still non-convoluted, it is much easier to correct at this time.

The RPE is an expander with two bands cemented onto last upper molars. They are connected by a metal screw that is turned daily to expand the appliance. Follow the dentist’s instructions regarding the turning schedule. We teach all our parents and caretakers how to turn the screw properly and easily. It usually takes two to four weeks to complete the active (or turning) part of treatment and following 6 months the appliance is passively providing retention. During the first two days, the patient may experience slight headaches and tightness, which is a normal effect. Over-the-counter pain medications will relieve any discomfort, but shouldn’t be needed for more than a couple of days.

What to Expect


Since the appliance is a foreign object, the patient may have difficulty speaking, chewing, eating and swallowing for the first few days, but after a couple of days children get used to it and do not experience any problems. Practicing speaking by reading a book aloud can help before the return to school. Soft diet will also help in those critical first days. To remove food particles trapped within the RPE, rinsing thoroughly with water after every meal and using a syringe that we will provide will help.

Parents have a special role to play in the whole procedure. They should help their children with the turning of the screw, assess any discomfort, keep them on regular checkup appointments, and help them get accustomed to the appliance in those first few days.

As you continue turning the screw regularly throughout the duration of active treatment, you may expect the following:

  • Gap of several millimeters between the two upper front teeth.
  • Pressure on the teeth, palate, cheeks and nose.
  • Easier breathing due to expansion of the palate and nasal passages.
  • Your bite may be off or not properly align because the upper jaw is currently expanding. It will stabilize in time.

The RPE treatment will require several appointments. First one is for impression of the upper and lower jaw. Two to three weeks later, during the second appointment, the dentist will seat the appliance (cement it) on the teeth and teach the parents how to turn the screw. Two weeks later will be first appliance check will take place and it could possibly be the final check. If your child needs a little more expansion, additional week or two of turning might be added. Finally, at that time the dentist will seal off the screw to prevent accidental turning back and monitor the expansion on regular checkup and cleaning appointments.