Dr. Kellyn Hodges describes what an orthodontic expander is. Sometimes called a palate spreader, this hardware gently expands the arch and widens the space between teeth. Dr. Hodges adjusts the pressure exerted by the expander during appointments.
This is an expander often times called a palate spreader or Hyrax,
it's designed to widen the upper arch. It's anchored to the upper molars
and there's a small jack-screw in the center. There is a hole in which you
insert the key to turn it. Insert it into the hole all the way. The key is
rotated 180 degrees. Once you have a full rotation you should see another
hole appear. Remove the key from the hole and remove it from the mouth.
Again, the purpose is to expand the upper arch and as you can see in
Jordan's arch she's got a small space occurring in the mid-line already.