A Rapid Palatal Expander (RPE) is a fixed orthodontic appliance used to widen the upper jaw when it is too narrow. This treatment is commonly recommended when one or both sides of the upper teeth bite inside the lower teeth—known as a crossbite. The RPE gradually expands the mid-palatal suture (the seam in the roof of the mouth), allowing the upper jaw to grow properly. This correction helps create space for permanent teeth to erupt and align, and it can prevent issues such as bite shifting and asymmetrical jaw growth.

The narrowing of the upper jaw can be caused by several factors, including airway problems, tongue posture, thumb-sucking habits, or genetics. Expanding the jaw early can correct these issues and reduce the need for more complex treatment later.

Who May Need a Palatal Expander?
Palatal expanders are most commonly used in growing children and young teens, while the bones are still developing. An orthodontist will determine if and when a patient is ready for an expander by evaluating age, skeletal maturity, and other individual factors.

Early expansion therapy can:

  • Prevent the need for permanent tooth extractions
  • Improve Airway and Breathing
  • Reduce the risk of impacted teeth
  • Avoid flaring of the front teeth
  • Help prevent jaw asymmetries that could require surgery if left untreated into adulthood

What Is a Palatal Expander?
The expander is made of two metal bands (rings) cemented to the upper back teeth, connected by a wire structure that sits along the roof of the mouth. In the center is a small expansion screw, which is turned with a special key to gradually widen the upper jaw. It’s normal to see a space develop between the front teeth during this process. After the desired expansion is achieved, the device remains in place for several months to allow the new bone to stabilize.

Adjusting to the Palatal Expander
Getting used to the expander takes a few days. It’s common to feel soreness in the back teeth with bands. Over-the-counter pain medication can help if needed. Eating may feel awkward at first—soft foods are helpful, and sticky items like taffy should be avoided as they can dislodge or damage the appliance.

Turning the screw should not cause pain, but slight pressure is normal. Our team will give you clear instructions on how often and how long to turn the key.

How to Turn the Expander Key

  1. Have your child lie back on a sofa or bed to simulate a dental chair.
  2. Use a flashlight or phone light to see clearly.
  3. Insert the key into the hole in the center of the expander.
  4. Push the key from the front toward the back until it stops.
  5. Gently remove the key by wiggling it out—do not reverse the turn.

Keeping the Expander Clean

  1. Brush at least twice a day.
  2. Clean thoroughly around the metal bands and the screw mechanism.
  3. Pay special attention to the roof of the mouth where food may collect.

When to Call Us
Please contact our office if you experience any of the following:

  1. A band becomes loose or unglued—stop turning the key.
  2. The wire becomes bent or detaches.
  3. The wire is poking or causing gum irritation.
  4. You have any questions or concerns about turning the key.