Underbite vs Overbite Jaw Surgery: Which Correction Do You Need?

Underbite and overbite are different types of malocclusion that can result from factors like tooth position, jaw structure, or even both. 

An underbite occurs when the lower teeth extend beyond the upper teeth, while an overbite involves excessive vertical overlap of the upper teeth. Mild or primarily dental cases may be treated with orthodontics, whereas significant skeletal discrepancies may require underbite jaw surgery, overbite surgery, or surgery involving both jaws.

Treatment is determined through clinical examination, dental measurements, imaging, and assessment of facial and functional concerns. The appropriate approach depends on the individual's jaw structure rather than the visible bite alone.

Key Takeaways

• Underbite jaw surgery may be considered when a significant skeletal discrepancy cannot be corrected with orthodontics alone.
• Overbite surgery may be appropriate when excessive overbite is linked to an underlying skeletal problem.
• Other malocclusion types, including open bite, crossbite, and severe jaw asymmetry, may also require surgery in selected skeletal cases.
• Jaw misalignment surgery is planned according to the position of the jaws, teeth, facial structure, and functional concerns.
• Orthodontic treatment may be used before and after surgery to prepare and refine the bite.
• Recovery typically involves swelling, dietary changes, activity restrictions, and follow-up care as the jaws heal.
• The most appropriate treatment cannot be determined by the visible bite alone; a comprehensive dental and skeletal assessment is necessary.

What Is the Difference Between an Underbite and an Overbite?

An underbite occurs when the lower front teeth extend beyond the upper front teeth, while an overbite refers to excessive vertical overlap of the upper teeth over the lower teeth.

Although both affect how the teeth meet, they involve different types of bite relationships and may have different underlying causes.

The appearance of the bite alone cannot determine whether surgery is necessary. A detailed dental and skeletal assessment is needed to identify the underlying cause and determine the most appropriate treatment.

What Is Underbite Jaw Surgery?

Underbite jaw surgery is an orthognathic procedure used to correct a significant skeletal discrepancy between the upper and lower jaws. An underbite may result from a lower jaw that sits too far forward, an upper jaw positioned too far backward, or a combination of both.

Rather than moving only the teeth, surgery repositions the jawbones to establish a more appropriate relationship. Depending on the patient's anatomy, treatment may involve the upper jaw, lower jaw, or both.

When Is Underbite Correction Surgery Considered?

Underbite correction surgery may be considered when the discrepancy is skeletal and cannot be adequately corrected with orthodontic treatment alone. The decision is based on the severity and cause of the jaw relationship as well as its effect on function and facial balance.

Surgery may be considered when:

• The discrepancy is primarily skeletal.

• Orthodontics alone cannot achieve the required correction.

• The jaw relationship causes functional difficulties.

• The jaw position contributes to significant facial imbalance.

What Is Overbite Surgery?

Overbite surgery is an orthognathic procedure used to correct an excessive overbite when the underlying problem is a significant skeletal discrepancy that cannot be treated with orthodontics alone.

While some overbites are primarily related to tooth position, others may involve the development or position of the jawbones.

When Does an Overbite Need Jaw Surgery?

An overbite may require jaw surgery when the skeletal discrepancy is significant and orthodontic treatment alone cannot achieve an appropriate functional and stable result. The decision depends on the underlying cause, severity, facial structure, and functional effects.

Surgery may become part of treatment when:

• The skeletal discrepancy is significant.

• Orthodontics cannot adequately correct the bite.

• The jaw relationship affects facial proportions or function.

• Orthodontic compensation would not provide an appropriate or stable result.

Malocclusion Types That May Require Jaw Surgery

Malocclusion types that may require jaw surgery include severe underbite, overbite, open bite, crossbite, and significant asymmetry when the underlying problem is skeletal and cannot be corrected with orthodontics alone.

• Open bite: The upper and lower teeth do not meet normally when the mouth is closed.

• Crossbite: Some upper teeth sit inside the corresponding lower teeth.

• Severe asymmetry: The jaws are positioned unevenly from one side to the other.

The presence of a malocclusion does not automatically mean surgery is necessary. Treatment depends on the severity of the discrepancy, its underlying cause, its effect on function and facial balance, and whether orthodontic treatment can provide an appropriate result.

Jaw Misalignment Surgery: How Is the Right Procedure Chosen?

The right jaw misalignment surgery is chosen by evaluating the underlying skeletal and dental relationships, facial structure, and functional concerns rather than relying on the visible bite alone.

The evaluation to choose the right procedure includes:

• Clinical examination

• Dental and facial imaging

• Measurements of the jaw relationship

• Assessment of tooth position

• Evaluation of facial symmetry and proportions

• Functional concerns

• Orthodontic treatment requirements

These findings help determine whether orthodontic treatment alone is appropriate or whether surgical repositioning of the upper jaw, lower jaw, or both jaws is necessary.

Underbite vs Overbite Jaw Surgery: Which Correction Do You Need?

The appropriate jaw surgery depends on the anatomical cause of the malocclusion, not simply whether the patient has an underbite or overbite. 

Underbite correction generally addresses a front-to-back discrepancy between the jaws, while overbite correction may involve an excessive vertical relationship between the teeth and underlying jaw structures.

A qualified orthodontist and oral and maxillofacial surgeon can determine the appropriate treatment based on the individual diagnosis, including the position of the jaws, teeth, facial proportions, and functional concerns.

What Happens Before Jaw Surgery?

Before jaw surgery, patients typically undergo detailed dental, skeletal, orthodontic, and surgical planning to determine the appropriate jaw movements and prepare the bite for the procedure. 

Orthognathic surgery is often part of a longer treatment process, with orthodontic treatment used before and after surgery when necessary.

Before the procedure, the treatment team may assess:

• Dental and skeletal measurements

• Dental and facial imaging

• Planned movements of the jaws

• Orthodontic preparation

• Surgical and anesthesia considerations

• Postoperative care and recovery requirements

Virtual surgical planning may also be used to evaluate the proposed jaw movements and assist with surgical preparation. The exact preparation process depends on the patient's diagnosis and treatment plan.

Recovery After Underbite or Overbite Surgery

Recovery after underbite or overbite surgery involves an initial period of swelling, discomfort, dietary restrictions, and limited activity, followed by gradual improvement as the jaws and surrounding tissues heal. 

The duration and progression of recovery depend on the type of surgery performed and the extent of jaw repositioning.

Recovery commonly involves:

• Early recovery: Swelling, discomfort, fatigue, and changes in eating and speaking are common. Physical activity may also be temporarily restricted.

• Ongoing healing: Swelling gradually decreases as the jawbones and surrounding tissues continue to heal, while the bite becomes more stable.

• Follow-up care: Appointments allow the surgical team to monitor healing and address any concerns during recovery.

• Orthodontic refinement: When orthodontic treatment is part of the treatment plan, postoperative adjustments may be used to refine the bite as healing continues.

Following the surgical team's instructions for diet, oral hygiene, activity, and follow-up care is an important part of supporting recovery.