A palatal expander, also known as a rapid palatal expander, rapid maxillary expansion appliance, palate expander, orthodontic expander, Haas, or Hyrax, is used to widen the upper jaw (maxilla) so that the bottom and upper teeth will fit together better. This is a common orthodontic procedure. The palatal expander “expands” (or widens) your upper jaw by putting gentle pressure on your upper molars each time an adjustment is made. The animation below will instruct you about when and how to adjust your expander. When you achieve the desired expansion, you will wear the appliance for several months to solidify the expansion and to prevent relapse. Although the use of an expander is most common in children, it can be and has successfully been used in adults, although the effects of expansion are slightly more uncomfortable. Also, depending on the amount of correction and age of the patient, it may result in surgical separation of the maxilla. Use of a palatal expander is most often followed by braces to straighten out all the teeth now that room has been created.
Adjusting the palatal expander
In a well-lit area, tip the patient’s head back.
Place the key in the hole until it is firmly in place.
Push the key toward the back of the mouth. You will notice the fender will rotate and the new hole will appear. The rotation stops when the key meets the back of the expander.
Press back and down toward the tongue to remove the key. The next hole for insertion of the key should now be visible.
Some most notable indications for the need of a palatal expander include: