Long Lower Jaw (Class III) Correction
An underbite, or a Class III bite orthodontically, can occur from one, or both, of two scenarios. In a Class III patient, either the top jaw has not developed forward enough in its relationship with the lower jaw, OR the lower jaw has grown forward excessively in its relationship to the top jaw. Commonly, patients with an underbite have a combination of both situations described above where the top jaw is too far back, and the bottom jaw is too far forward. Early treatment of this type bite is recommended in order to attempt avoiding future jaw surgery to correct the issue. Below is an example of one type of appliance aimed at correcting this type of problem.
Reverse-pull headgear, or a face mask, is a removable appliance used in correction of a Class III skeletal malocclusion, due to an underdeveloped upper jaw and slightly overdeveloped lower jaw. The appliance is worn for a minimum of 14 hours per day, after school, to help pull the upper jaw forward in growing children and adolescents. Several skeletal and dental changes are achieved with this early treatment to improve the malocclusion and the soft tissue profile. The earlier the correction and the longer the treatment time, the greater the chances that the maxillary protraction will be maintained.
***Following facemask therapy, the Class III growth pattern reasserts itself; therefore vigilance in continuing to follow-up during retention is recommended.
Download our Facemask handout for more information.