Surgery to correct facial disproportion (Orthognathic surgery)

Some people grow to have an imbalance between their upper and lower jaws; which can result in facial disproportion or asymmetry. Correcting this often requires more than just alignment of teeth with orthodontics. Surgery in combination with orthodontics pre and post-operatively, can modify the relationship between your upper and lower jaw and correct facial asymmetry.

The surgery is carried out under a general anaesthetic. The majority of the operation is done from the inside of your mouth except a three millimeter incision on the cheek. This helps to minimize any visible scars on the skin of your face.

Planning for your Surgery

Perhaps surprisingly it is often described by patients as not a particularly painful operation but there will be some degree of discomfort post-procedure and regular painkillers will be arranged for you. This is usually worse for the first few days although it may take a couple of weeks to completely disappear. It is also necessary to make sure that the area heals without any infection and so you will be given antibiotics through a vein in your arm whilst you are in hospital. You will be sent home with painkillers and a course of oral antibiotics on the following day.

Immediately after the operation, your face will be swollen and feel tight, your jaws will be stiff and you will find that you cannot open your mouth very wide. Your throat may also be uncomfortable and swallowing could be difficult to begin with for a couple of days.

Swelling and bruising which occurs after the procedure is variable but is generally worst on the second or third day after the operation. The swelling can be reduced by using cold compresses and sleeping propped upright for a couple of days. Most of the swelling has disappeared after a fortnight. There is often some subtle swelling that can take several months to disappear although only you and your family are likely to notice this.

Recovery time after Mandibular Osteotomy Surgery

Initially you will be on a very soft diet and you will need a food processor at home to help with food preparation. After the first week or so you will be able to eat soft food. Being able to eat a normal diet usually returns over a six to eight week period.

Usually patients go home the following day after surgery, however sometimes two nights in hospital may be needed depending on home circumstances. You will be seen again in clinic one week following your surgery.

Possible complications after surgery

While complications can occur during any of the dental, orthodontic, or surgical phases of treatment, complications specifically related to the surgical procedure are summarised below:


  • Injury to the inferior alveolar nerve: The risk of injury to this nerve is approximately 2-3.5%. In the patients undergoing this procedure, 10-30% of them experience some neurological damage of varying degrees. Not all of these have symptoms from the nerve damage. When the sagittal split osteotomy is combined with an osseous genioplasty, nearly 70% of patients have some degree of neurosensory deficit a year post-surgery. This is the accepted tradeoff (benefits outweighing risks) that patients must accept in mandibular surgery.
  • Bleeding (from damage to the inferior alveolar artery, masseteric artery)
  • Repositioning: a tendency for the jaws to revert to the pre surgical position, though not to the full extent that they were.


  • Unanticipated fractures and/or unfavorable split requiring wiring of teeth together during the initial healing phase
  • Avascular necrosis of the jaw has been reported in very rare case
  • Condylar resorption in very specific cases causing an increased relapse of occlusion. Your personal risk will be discussed at consultation.
  • Malpositioned proximal segment