Orthodontic Expanders

An expander, also called a rapid palatal expander or RPE, is an appliance designed to correct a narrow upper arch that can result in crossbite, crowding, or impacted teeth. Two bands are cemented onto the last upper molars and connected by a metal screw that gets turned regularly to expand the appliance.

While not used as often, a lower expander can move lower teeth that have become tipped in into an upright position.  This does not actually widen the bone, but instead just uprights the teeth to improve their position and help alleviate crowding.  Additionally, lower appliances commonly accompany an upper RPE.

How An Expander Works

Always follow the instructions given to you by Dr. Kelley or Dr. Gardner regarding how often to turn your RPE. Expanders follow a process of active treatment (regular turning of the RPE) followed by a resting phase where the appliance passively provides retention as the palate adjusts.

Palate Before Expander
Palate after expander

During active treatment, you may begin to notice:

  • Small gap between your two upper front teeth
  • Some pressure on the teeth, palate, cheeks and nose, which subsides within minutes after turning
  • Easier breathing because of nasal passages expanding as the palate enlarges
  • Changes to your bite, and new alignment issues. This will stabilize in time.
Expander is placed in mouth
Key turns expander
Expander rests to allow growth to "set"

Placing an expander will take several appointments.

  1. Digital scan of the upper and lower jaw
  2. Placement of separators one week prior to delivering the expander.
  3. Seat the expander on the teeth and teach parents how to turn the screw.
  4. Appliance checks to determine if you need additional time turning the screw.

If you have questions, or would like to know more about Kelley & Gardner Orthodontics, please contact us.