This surgery is often necessary when jaw growth problems cannot be resolved by orthodontic treatment alone. It may be proposed to correct:

• A chin that is too far forward (prognathism) or too far back (retrognathism).
• A set-back chin (receding chin)
• Resting lip incompetence (lips that do not touch at rest)
• A barely visible smile (upper teeth set back or hidden behind the upper lip).
• A gummy smile (gums that are too visible).
• Problems with chewing, swallowing or breathing (in particular sleep apnea).
• A face that is too long or too short, with problems chewing, swallowing or breathing (in particular sleep apnea).
• Jaw angles that are too pronounced or not pronounced enough
• Facial asymmetry

Orthognathic surgery is for adolescents and adults. Most patients are referred for this surgery by their orthodontist, who judges that the skeletal deformities are too significant to be corrected by braces or aligners alone.

The success of orthognathic surgery relies on close collaboration between two specialists: the orthodontist and the surgeon. The orthodontist prepares the dental arches and aligns the teeth on their bony base so that the jaws can be positioned correctly. The maxillofacial surgeon then intervenes to reposition the jaws according to the plan drawn up together. This teamwork, which begins well before the operation, is fundamental to achieving an optimal aesthetic and functional result.

Treatment takes place in several phases:

1. Preparatory phase (orthodontics): orthodontic treatment is carried out beforehand, generally over 8 to 18 months, to align the teeth correctly on each dental arch in preparation for the operation.
2. Surgical phase: the operation is performed under general anaesthesia. The incisions are made inside the mouth (no visible scar on the face). Bone surgery (osteotomy) places the jaws in their new position. The bone is stabilised (osteosynthesis) with small titanium plates and screws that are discreet and not palpable.
3. Postoperative phase (recovery and orthodontic finishing): The hospital stay is 24 hours (one night on site). Patients return home the day after the operation. Orthodontics resumes 4 to 8 weeks later to finalise the occlusion (the way the teeth fit together) and complete the treatment (allow 3 to 6 months).

Contrary to what one might think, orthognathic surgery is generally not very painful. Facial oedema (swelling) is common and can last several weeks. Pain management is very well supervised by the medical team. The patient returns home the day after surgery and takes oral medication for 5 days with mild painkillers.

As with any surgical procedure, there are risks, but they are rare and well controlled:

• Infection: antibiotics are prescribed to minimise this risk.
• Numbness: Reduced sensitivity of the lower lip is very common after the operation but temporary. It usually resolves within 4 to 8 weeks.
• Failure of bone healing. This complication is exceptional; following an appropriate (blended) diet for 6 weeks helps to limit this risk.
• Compressive haematoma. This complication is exceptional and rarely requires further intervention
• Suboptimal or imperfect result: fortunately rare. It may involve an occlusal imperfection (which will be corrected by postoperative orthodontics and, more rarely, by a second operation) or an aesthetic one (rare when the expected morphological changes and aesthetic expectations are discussed during the preoperative consultations ahead of surgery)

The operation is only scheduled after the patient has given informed consent.

• Hospital stay: the hospital stay is one night (discharge the day after the operation).
• Time off work: 1 to 4 weeks off work or school is generally needed while the swelling subsides.
• Diet: the diet is liquid for the first few days and then blended for 6 weeks.
• Sports: Sports with no risk of impact can be resumed after 1 month. All sports can be resumed after 2 months.

After orthognathic surgery, recovery is gradual. It should be active, with the help of maxillofacial physiotherapy.

• Speaking: it is entirely possible to speak and make phone calls.
• Eating: The diet is liquid or soft. You can eat anything that can easily be mashed with a spoon or fork. A blended diet promotes recovery and mouth opening. Feeding with a syringe or straw is not necessary and slows down recovery.
• Hygiene: Brushing the teeth with a normal toothbrush and using mouthwash are essential. The incisions are not in contact with the teeth, so brushing cannot delay healing.

To reduce swelling (oedema) after orthognathic surgery, it is recommended to follow these instructions, which are particularly important during the first 5 days when the swelling is at its peak:

• Cold application: apply ice packs or a cooling mask to the cheeks in cycles of 15 to 20 minutes, several times a day. This method promotes vasoconstriction, which limits fluid build-up and prevents pain. After 48 hours it becomes less useful.
• Head elevation: sleeping in a semi-upright position (at 45 degrees) or with the head raised on several pillows during the first few nights promotes lymphatic drainage and helps reduce the oedema.
• Walking: intense exertion should be avoided, but it is important to be mobile from the day after surgery. Walking one to two hours a day (cinema, a stroll, a museum visit) is recommended, as it contributes to lymphatic drainage. Gentle physical activity is therefore advised.
• Moist heat: after 48 hours, switching to moist heat (a warm compress, a heat pack) can help soften the tissues and promote the resorption of the oedema.
• Hydration and nutrition: staying well hydrated by drinking 2 to 3 litres a day is important. A healthy, protein-rich diet also aids healing.
• Medication: carefully following the medical prescription, which includes anti-inflammatories and painkillers, helps manage pain and inflammation.
• Gentle mobilisation: physiotherapy exercises (lymphatic drainage, massage) and gentle mobilisation of the face (speaking, smiling) are recommended to aid recovery.

A gradual return to gentle sports and muscle strengthening is possible from 7 to 10 days (i.e. after the first postoperative visit). Team and contact sports can be resumed after 6 weeks (the time needed for bone healing).

Orthognathic surgery is a surgical procedure which, when justified by a skeletal discrepancy, is covered by the French national health insurance (Sécurité Sociale, CPAM) as part of the coordinated care pathway. CPAM reimbursement is 100% of the standard agreed rate. The fees of the surgeon and the anaesthetist and the hospital costs may vary according to agreements and any additional fees, and are partly covered by complementary health insurance (mutuelles). Pre- and postoperative orthodontic costs are covered by the national health insurance up to the age of 16. Cover by complementary health insurance is possible in addition or beyond that age.

Although rehabilitation is mainly postoperative, preparation may be recommended. The physiotherapist can:

• Assess function: carry out a precise assessment of jaw mobility, tongue position, swallowing and speech.
• Correct dysfunctions: start working on bad habits (such as poor tongue position) and any muscle imbalances to prepare the muscles for surgery.

The physiotherapist can intervene from the first few days to relieve the patient and initiate recovery:

• by fighting the oedema: performing manual lymphatic drainage of the face and neck to help reduce the swelling.
• by relieving pain: through gentle massage and relaxation techniques, the physiotherapist helps manage postoperative pain.
• by ensuring good nasal breathing, which is often affected by the swelling.

This phase is the most important and continues over several weeks. The physiotherapist supports the patient and helps them:

• to regain mobility: through gentle mobilisation exercises and stretching, the physiotherapist helps the patient recover the jaw’s range of motion, which is initially limited by the swelling and the surgery.
• to retrain the muscles: targeted exercises are proposed to strengthen the chewing muscles and restore effective, comfortable chewing.
• to work on orofacial functions: by retraining speech, swallowing and tongue position so that these functions adapt to the new jaw position.
• to improve healing: specific massage helps soften scar tissue and prevent adhesions that could restrict movement.

· Advice and self-management: the physiotherapist teaches the patient self-rehabilitation exercises to do at home to maintain progress and stabilise the results in the long term.

It is important to make an appointment at the start of the protocol (as soon as the braces are fitted), in order to carry out an assessment and establish a schedule in line with the orthodontic and surgical treatment plan.

There are physiotherapists who specialise in maxillofacial surgery; you can find their contact details on the website of the international society of lingual and oro-maxillofacial physiotherapy (https://siklomf.fr)

• • Preoperative phase: the nutritionist helps prepare the patient by making sure they are in good physical condition before the operation is scheduled. They can also give advice on meals before surgery and on hydration.
  • Postoperative phase: this is the most important phase because orthognathic surgery leads to relative immobilisation of the jaws. The nutritionist then draws up a suitable eating plan, which prevents weight loss and ensures a sufficient intake of the nutrients essential for healing and bone consolidation.

  This plan unfolds in several stages:

  o Liquid phase: immediately after the operation, the diet is exclusively liquid. The nutritionist suggests ideas for soups, smoothies, liquid purées, drinking yoghurts and fortified drinks. They stress the importance of eating foods rich in protein, vitamins (C and D) and minerals (calcium, zinc) for good healing.

  o Blended/soft phase: the patient gradually moves on to a blended, then soft, diet. The nutritionist guides the patient in preparing meals, giving tips for enriching dishes (for example with powdered milk, cream or melted cheese) and making them tastier despite the lack of chewing.

  o Reintroduction of solid foods: the nutritionist supports the patient through the gradual return to a normal diet, in line with the surgeon’s recommendations. They help the patient relearn chewing movements and rediscover the pleasure of eating.

  The nutritionist plays an essential supporting role by providing personalised advice and recipe ideas to meet the dietary challenges that follow orthognathic surgery.

It is a virtual plane passing through the cusp tips of the incisors and the second molars. Its inclination relative to the skull base is a key parameter in facial analysis.

During the operation, the surgeon rotates both jaws by lowering the molars while generally keeping the interincisal point at the same height. This rotation reduces the angle of the occlusal plane.

o Reduction of the lower facial height: this surgery shortens the ‘long face’ appearance by raising the chin.

o Chin projection: counterclockwise rotation of the mandible brings the chin forward, which in some cases can avoid the need for a genioplasty (chin surgery).

o Improved profile harmony: this procedure helps better define the chin and neck line.

o ‘Reverse face lift’ effect: advancing the lower third of the face tightens the soft tissues of the facial mask, improves the chin-neck distance (disappearance of the double chin), and puts the skin of the neck and face under tension. This is a reverse lifting effect: the skin is re-tensioned with a stable, lasting result.

o Improved breathing: by advancing the jaws, counterclockwise rotation increases the volume of the oropharyngeal airway. This is particularly beneficial for patients suffering from obstructive sleep apnea (OSA).

o Stability: Counterclockwise rotation is considered a stable technique in the long term, although concerns have been raised about tension in the muscles and the temporomandibular joints.

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