The length of time it takes for braces to correct an underbite varies between patients and is heavily dependent on the severity of the underbite, but patients typically wear the braces for 1 to 3 years or more, as stated by Dental Associates. Refer to a licensed orthodontist for an accurate prognosis.
Once the braces have been affixed, the underbite can be corrected by attaching elastics to the hooks on the brackets. An orthodontist will assess the underbite and will likely hook the elastic band on one of the upper molars as well as on a lower cuspid, which will pull the jaw back and move it into alignment, according to AvA Orthodontics. The correction plan will depend on the patient and the severity of the malocclusion; if the underbite is extreme and cannot be relieved with braces, jaw surgery may be necessary, notes the National Institutes of Health's MedlinePlus.