[medical citation needed] Other forms of headgear treat reverse overjets, in which the top jaw is not forward enough.
Facemask or reverse-pull headgear is an orthodontic appliance typically used in growing patients to correct underbites (technically termed Class-III orthodontic problems) by pulling forward and assisting the growth of the upper jaw (maxilla), allowing it to catch up to the size of the lower jaw (mandible).
[1] The appliance normally consists of a frame or a center bars that are strapped to the patient's head during a fitting appointment.
These elastics are then hooked onto the patient's braces (brackets and bands) or appliance fitted in his or her mouth.
Many parents and doctors recommend using early intervention (typically between ages 7 to 13) by using a facemask to avoid costly and painful surgical procedures later.
[1] The appliance is very effective in correcting Class III orthodontic problems in younger or adolescent patients that are still growing.
[1] Researchers who have studied the long-term effects of orthodontic headgear have found that it may flatten the face and prevent the chin from coming forward, pushing both the upper and lower jaw down and back, into the airway.
In more technical terms, it inhibits the natural growth of the jaws and lead to a reduction in the SNA and ANB angles, which relate to the forward position of the maxilla and the mandible.
[4] Teenagers prescribed orthodontic headgear often face social stigma and bullying if seen wearing these appliances.