Orthognathic surgery

Orthognathic surgery is a procedure designed to correct jaw imbalances in patients with severe malocclusions or facial skeletal anomalies. These mismatches between the upper jaw (maxilla) and the lower jaw (mandible) can lead to difficulties in chewing, speaking and breathing, as well as major aesthetic complexes.

It is often performed on younger patients, between the ages of 16 and 35, but can also be considered later, depending on the case. This surgery is always preceded and followed by orthodontic treatment, which requires close collaboration between the orthodontist and the maxillo-facial surgeon.

What are the indications for orthognathic surgery?

Orthognathic surgery is indicated in several situations, including:

• Overshot: lower jaw too far forward
• Retrognathism: lower jaw set back
• Anterior open bite: inability to close the front teeth
• Facial asymmetry
• Gingival smile: excessive exposure of the gums of the upper jaw during an unforced smile
• Functional disorders: difficulty chewing, joint pain, sleep apnea
• Aesthetic consequences: inharmonious profiles, receding or protruding chin, unbalanced lips…

These disorders are often due to uneven or hereditary bone growth, but can also result from trauma or developmental abnormalities.

What happens when orthognathic surgery is combined with orthodontic treatment?

Treatment always begins with a so-called “pre-surgical” orthodontic phase, lasting an average of 12 to 18 months. The orthodontist aligns the teeth with their respective bony bases, even if this temporarily worsens the malocclusion. This allows the surgeon to reposition the jaws without dental stress during surgery.

Surgery then takes place, under general anaesthetic, and generally lasts between 2 and 4 hours, depending on the procedures involved. A short hospital stay is sometimes necessary (2 to 4 days on average), followed by time off work.

After surgery, a post-operative orthodontic phase is used to finalize the occlusion (approx. 6 months).

What are the main orthognathic surgeries performed?

Osteotomy of the maxilla (Le Fort I)

This technique allows the jawbone to be repositioned in all three dimensions of space: upwards or downwards (to correct a gingival smile or a gap), forwards or backwards (to correct a jawbone that is too protruding or too short), or asymmetrically (in the case of deviation).

The surgeon makes a horizontal cut through the jawbone (called “Le Fort I”) to mobilize it, then fixes it with titanium plates and screws.

Mandibular osteotomy (bilateral sagittal or OSBM)

It allows the lower jaw, called the mandible, to be moved forward or backward, and can also be used to correct asymmetry. Two cuts are made on either side of the mandible to allow displacement of the bone block containing the teeth.

Fixation is achieved with mini-plates and screws, without external immobilization. The occlusion is stabilized with elastics between the teeth.

Genioplasty (chin surgery)

Chin surgery (genioplasty) can be performed alone or in conjunction with maxillary and/or mandibular osteotomies. It enables :

• A receding chin
• Retracting an over-projected chin
• Correcting asymmetry or deviation
• Adjust chin height

This surgery has a major impact on facial profile and overall harmony. It is often used for aesthetic purposes, but can also improve breathing and lip closure.

Essential collaboration: orthodontist & surgeon

Successful treatment depends on close collaboration between orthodontist and surgeon. The treatment plan is defined together, in agreement with the patient, after a precise analysis of clinical, photographic, radiological (3D scans, teleradiographs) and digital (modelling) data, according to jaw misalignments, tooth position and other parameters gathered during the consultation.

The surgical project is simulated to accurately predict bone displacements. This planning is essential to ensure functional harmony (chewing, speaking, breathing) and aesthetic harmony (profile, smile, symmetry).

What happens after the operation?

The post-operative after-effects are generally well tolerated:

• Moderate swelling for 1 to 2 weeks
• Pain controlled by simple analgesics
• Liquid or blended food for 10 to 15 days
• Resumption of activities in 3 to 4 weeks
• Non-dental aesthetic results are visible from the first month, but the final result can be appreciated after 6 months.

Regular appointments are scheduled with the surgeon and orthodontist until complete stabilization and finalization of treatment.

Orthognathic surgery is a comprehensive treatment that profoundly transforms patients’ quality of life, both functionally and aesthetically. It requires patience, rigor and an experienced team (orthodontist, surgeon, operating team), but the results are often spectacular and long-lasting.

If you think you may be affected by jaw misalignment or functional or cosmetic discomfort, don’t hesitate to make an appointment for an initial consultation.