The palatal expander "expands" (or widens) your upper jaw by putting gentle pressure on your upper molars each time an adjustment is made. The video 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 regression.
Adjusting the palatal expander
You can also download these instructions in a printable PDF document.
Palatal Expander for Early Treatment (Phase 1)