Orthognathic Surgery: What It Is, How the Procedure Works and What to Expect

Orthognathic surgery is the treatment of choice when problems with the bite or facial harmony are not caused by the teeth themselves, but by the position of the jaw bones. It is a well-established procedure with permanent functional and aesthetic results, although it can understandably raise many questions. In this article, we explain what orthognathic surgery is, what the operation involves, which conditions it can correct and what you can expect.

What is orthognathic surgery?

Orthognathic surgery is a surgical procedure used to correct abnormalities in the position of the upper jaw, lower jaw or both when they affect the bite, oral function, facial symmetry or overall facial harmony. By carefully repositioning these bones — and, with them, the chin and midface — the procedure can achieve a more balanced and proportionate facial appearance and a functional bite.

It is important to understand that orthognathic surgery addresses two objectives at the same time: a functional objective — improving chewing, speech and breathing, while helping to protect the teeth, gums and jaw joints — and an aesthetic objective, by improving facial appearance and the smile. These skeletal discrepancies affect a significant proportion of the population and, in many cases, cannot be corrected with orthodontic treatment alone.

What the operation involves and what to expect. The process begins with a detailed assessment using X-rays, models and digital planning. During surgery, the incisions are made inside the mouth, so there are no visible external scars. The bones are then accessed, repositioned and secured using plates and screws. As a general guide:

• Duration: usually between 2 and 5 hours, depending on the complexity of the procedure.
• Anaesthesia: general anaesthesia.
• Hospital stay: normally 1–2 days.
• Initial recovery: approximately 4–6 weeks before returning to normal activities, with swelling and a soft diet during the first few days; full recovery may take up to 6 months.
• Results: permanent.

You can find full details about the procedure and its different approaches on the Face Clinic orthognathic surgery page.

Orthognathic surgery vs orthodontics: when orthodontics alone is not enough

Orthodontics moves the teeth, but it does not change the position of the jaw bones. When the problem is dental — teeth that are poorly aligned on an otherwise correctly positioned skeletal base — orthodontic treatment alone is often sufficient. However, when the underlying cause is skeletal — because the upper or lower jaw is incorrectly positioned — simply aligning the teeth does not correct the underlying problem and may result in an unstable or unnatural outcome.

In these cases, the two treatments are combined: a period of orthodontic treatment before surgery is usually carried out to position the teeth correctly, followed by surgery to reposition the jaw bones, and finally a period of post-surgical orthodontic treatment to refine the result. You can read more about this final stage in our article on orthodontics after orthognathic surgery.

After surgery, orthodontic elastics are commonly used to help guide the bite into its new position; here we explain what elastics are and why they are used after orthognathic surgery.

Conditions treated with orthognathic surgery

These are the main skeletal abnormalities that may require this type of surgery.

Receding or protruding lower jaw

These are two of the most common reasons for treatment:

• Receding lower jaw (Class II): the lower jaw sits too far back in relation to the upper jaw, often resulting in a profile with a less prominent chin. You can find out more about a receding jaw and how to correct a Class II bite.
• Protruding lower jaw (Class III or prognathism): the lower jaw projects forwards in relation to the upper jaw, affecting both the bite and the facial profile.

In both cases, surgery repositions the lower jaw — and, where necessary, the upper jaw — to achieve a more balanced bite and facial appearance.

Open bite: when the teeth do not meet

With an open bite, the front teeth do not meet when the mouth is closed, even though the back teeth may still come into contact. When the cause is skeletal, this type of malocclusion can be difficult to correct with orthodontics alone and may affect chewing, facial aesthetics and speech.

Facial asymmetry of skeletal origin

When one side of the face is not symmetrical with the other because of differences in the growth or position of the facial bones, orthognathic surgery can reposition the upper and lower jaws to achieve greater facial balance while also improving functions such as chewing.

Associated breathing and swallowing problems

Some jaw abnormalities can reduce the space available in the airway and may be associated with sleep apnoea, snoring or swallowing difficulties. In selected cases, advancing the jaws can increase the airway space and improve breathing and sleep, as well as correcting the bite.

What happens if it is left untreated? Long-term consequences

Without treatment, a skeletal jaw abnormality is unlikely to improve on its own and may lead to additional problems over time. Some of the most common consequences include:

• Uneven tooth wear and excessive loading of certain teeth because the bite does not distribute forces correctly.
• Temporomandibular joint (TMJ) problems, including pain, tension or clicking.
• Difficulty chewing properly, which may affect digestion.
• Speech or pronunciation difficulties in some cases.
• Worsening breathing and sleep problems when an airway component is present.
• Aesthetic and psychological impact related to the facial profile or asymmetry.

The aim is not to be alarmist, but preventive: early diagnosis and appropriate planning make it possible to address the underlying problem and reduce the risk of these difficulties becoming more pronounced over time.

When should you seek an assessment for orthognathic surgery?

It may be advisable to seek an assessment from an oral and maxillofacial surgeon if you have a bite that does not fit together correctly — where the teeth do not meet properly — a significantly protruding or receding lower jaw, facial asymmetry, or if previous orthodontic treatment has not achieved a stable result. Assessment may also be appropriate if bite problems occur alongside snoring or sleep apnoea.

An important consideration is timing: orthognathic surgery is generally considered once skeletal growth has been completed, so age and stage of development are taken into account when planning treatment. You can read more about when the jaw stops growing.

During the assessment, a complete facial, dental and radiological evaluation is carried out to determine whether orthognathic surgery is the appropriate treatment and how the procedure should be planned. At Face Clinic, each case is assessed individually by a team specialising in oral and maxillofacial surgery and orthodontics. If you recognise any of these signs, you can request a consultation to determine whether this type of treatment may be appropriate for your case.