An underbite is a dental misalignment where the lower teeth and jaw protrude past the upper teeth when the mouth is closed. This condition can affect chewing, speaking, and facial aesthetics. The total timeline for correction is highly individualized, depending on biological and therapeutic factors. Duration can range from just over a year for a minor dental correction to several years for a complex skeletal issue in an adult.
How Severity and Cause Determine Treatment Path
Diagnosing the specific cause of the underbite is essential, as it generally falls into two categories. A Dental Underbite is the less complex form, where misalignment is primarily due to the position of the teeth, while the jaws are relatively well-aligned. Correcting this type usually requires only tooth movement and is the fastest to resolve.
A Skeletal Underbite, also known as a Class III malocclusion, is more involved and caused by a size mismatch between the jaws. This occurs when the lower jaw has outgrown the upper jaw, or the upper jaw is underdeveloped. The severity of this discrepancy directly scales the complexity and length of treatment, often requiring procedures that modify jaw growth or surgically reposition the bones.
Treatment Timelines for Early Intervention (Children and Adolescents)
For children and adolescents, underbites are addressed through interceptive orthodontics, which capitalizes on the body’s natural growth period. This early treatment, ideally starting around age seven to ten, aims to guide the developing jaw bones into a more favorable relationship. Interventions focus on encouraging the upper jaw’s forward development, as it completes most of its growth relatively early.
A common approach uses functional appliances, such as a reverse-pull face mask combined with a palate expander. The expander widens the upper arch, while the mask applies gentle, forward-pulling force to the upper jaw. This active treatment phase typically lasts between 9 and 18 months. The goal is achieving a slight over-correction to buffer against future lower jaw growth.
After active correction, a necessary “resting period” follows for several years while the remaining permanent teeth erupt. During this time, the orthodontist monitors the bite to prevent relapse or excessive lower jaw growth. This observation period is part of the overall multi-year process, often followed by a “Phase II” of traditional braces in adolescence to finalize tooth alignment.
Adult Correction Methods and Associated Durations
Once skeletal growth is complete, treatment methods shift because the jaw bone structure can no longer be modified without surgery. For mild to moderate underbites that are primarily dental or have a small skeletal component, Orthodontic Camouflage is a non-surgical option. This involves using braces or clear aligners to move the teeth to conceal the jaw discrepancy.
Camouflage treatment typically ranges from 18 to 30 months, depending on the required tooth movement and whether extractions are necessary. This technique is effective only when the skeletal problem is not severe, as it relies on tilting the teeth to create a proper bite relationship.
For more pronounced skeletal underbites, the only definitive solution is Surgical Correction, also known as orthognathic surgery. The surgical timeline is a prolonged, multi-stage process that spans two to three years in total.
Surgical Correction Stages
The process involves three main stages:
- Pre-surgical orthodontics, where braces are worn for 12 to 18 months to align the teeth properly over the jaw bones.
- The surgery itself, which involves repositioning the lower jaw backward or the upper jaw forward, followed by an initial recovery of four to six weeks.
- Post-surgical orthodontics, lasting an additional six to twelve months, to fine-tune tooth positions and stabilize the bite relationship.
The Retention Phase Defining a Permanent Fix
The active treatment period is followed by the Retention Phase. This stage is necessary to stabilize the new tooth and jaw positions and prevent the teeth from shifting back toward their original misalignment, a phenomenon called relapse. The tissue fibers and bone surrounding the teeth need time to reorganize and solidify around the corrected positions.
Retention involves the diligent use of retainers, which can be either removable devices worn nightly or fixed wires bonded discreetly to the back of the front teeth. The most intensive period of retention is the first year or two following the removal of braces or appliances.
Because the forces that cause teeth to move are constant throughout life, orthodontists often advise that retention is a lifetime commitment. Nightly wear of a removable retainer becomes the standard for maintaining the corrected bite indefinitely. Failure to follow the retention protocol risks undoing years of active treatment.