Attached to the upper molars through bonding or by cemented bands, the Rapid Palatal Expander (RPE) is an orthodontic device used to create a wider space in the upper jaw. It is typically used when the upper jaw is too narrow for the lower jaw or when the upper teeth are crowded or blocked out of the dental arch. When patients are still growing, their connective tissue between the left and right halves of their upper jaw is very responsive to expansion. By simply activating the expander through turning a screw in the center of the palatal expander with a special key we provide, gradual outward pressure is placed on the left and right halves of the upper jaw. This pressure causes an increased amount of bone to grow between the right and left halves of the jaw, ultimately resulting in increased width.