Call 717-761-3402
  • Camp Hill , PA - 3412 Trindle Rd. 17011
  • Harrisburg, PA - 3925 Linglestown Rd. 17110
  • 717-761-3402 | Camp Hill , PA - 3412 Trindle Rd.
  • 717-652-0828 | Harrisburg, PA - 3925 Linglestown Rd.

Hyrax Expander


The Hyrax Palatal Expander is used to widen the upper arch thus creating more space for the patient’s permanent teeth. It is an all metal appliance which is cemented to the upper 6 year molars and sometime the upper first bicuspids. The hyrax can be used in conjunction with full “braces” in older, actively growing patients. The Hyrax will be activated by turning front to back 1 turn for 28 days.   After 28 days of turning the expander will locked and maintained in place for 4 months. It is during this rest period that the palatal bone matures. At the end of the four months, the RPE will be removed and a space maintaining device such as a shell plate is often prescribed.


1.       Turn the expander appliance front to back 1 turn each day (unless otherwise instructed) with the key provided. Do not reverse the turn or it will not expand.  It is recommended to do turns at bedtime, since teeth do most of their moving immediately following the activation.

2.       Patients occasionally experience tooth sensitivity while wearing an expander. This is normal since the function of the appliance is to move the teeth and widen the palate. Treat discomfort with over the counter pain medication. If patient experiences severe pain, contact our office.

3.       Initially the bands on the Hyrax may cause sores by rubbing against the inside of the cheeks. Use Peroxyl or warm salt water rinses (1tspn per 8oz water) three times daily to sooth. Place wax over the offending bracket. Eventually calluses will form where the sores are.

4.       Patients will often notice that their “bite” feels different. This is normal and will end once expansion is complete. The patient will quickly get adapt to their new bite.

5.       Make sure the expander is kept clean. Brushing and flossing the banded molars is important! It is recommended to use a Water-Pik to aid in cleaning the appliance. If the gum tissues begin to swell around the appliance because of poor hygiene, contact our office.

6.       If the appliance should become loose, usually from a broken band, call our office immediately. DO not continue to turn the appliance if any looseness is visible.

7.       If the patient feels no tightening in the mouth after the expander is turned, stop turns and contact our office during normal office hours to be checked.

8.       Any questions regarding your Rapid Palatal Expander appliance should be directed to the orthodontic staff.


1.       Hard, Crunchy Foods such as:  Hard pretzels, nuts, jaw breakers, hard candy, ice.

2.       Gummy, Sticky Foods such as:  Gum, gummy bears, caramels, Jolly Ranchers, licorice, Fruit Roll-ups, Jelly Beans, Taffy, etc.  If it sticks to your teeth, just avoid it.

3.       Popcorn! Popcorn kernels often wedge between the expander and the palate, or under the gums at the molar bands. This can cause irritation and inflammation of the gum tissue. It is difficult to remove them with brushing and flossing.