The Medicolegal Challenges of Orthognathic or Temporomandibular Surgery

15 Jan 2021

Orthognathic surgery, or corrective jaw surgery, is used to treat skeletal deformities of the face that cause misalignment of the jaws and/or teeth as well as treating sleep apnoea patients . These conditions, which cannot be treated with conventional orthodontic procedures, include protrusion or recession of the jaws or chin, severe malocclusion and overbite. They can result in many issues, such as breathing difficulties; persistent pain in the jaw or temporomandibular joint (TMJ); difficulty in chewing, biting or swallowing; speech problems and an unbalanced facial appearance. Orthognathic surgery involves repositioning all or part of the upper jaw, lower jaw or chin. It is complex surgery and is normally carried out by an oral and maxillofacial surgeon.  Mr Zaid Sadiq, Consultant Oral and Maxillofacial/Head and Neck Surgeon, discusses the medicolegal challenges.

While complications from orthognathic surgery are rare, they can be life-threatening, due to the proximity of important structures within the cranium. As orthognathic surgery has become more accepted, the number of procedures carried out has increased. In tandem with this, the number of cases brought against surgeons appears to be rising each year. Estimates for the frequency of complications range from 1.5% to 25%. However, it is thought that the number of complications is underestimated.  

The commonest complication in this type of surgery is injury to the cranial nerves, which may result in alterations in sensitivity, and it accounts for around 50% of all complications reported. Laceration or disruption due to stretching, particularly of the inferior alveolar nerve (IAN), may occur during surgical techniques such as bilateral sagittal split osteotomy. Nerve injuries, which can be classified by neurophysiologic examination, may be demyelinating or axonal. Demyelinating nerve injuries usually recover within 2–4 months by a process of remyelination, and there is little risk of neuropathic pain developing. However, recovery after axonal injury is often slow, taking months or years, and incomplete. There is also a higher risk of chronic pain associated with this type of nerve injury.  

Subjective symptoms of sensory alteration are experienced by the majority of patients after surgery, but most resolve within a year. Again, axonal injuries are associated with a worse prognosis than demyelinating ones. Sensory alterations can be problematic for patients, as they not only feel unpleasant but can affect facial function. Issues include drooling; undetected food particles remaining around the mouth; speech difficulties; painful gingiva, resulting in poor oral hygiene habits, and difficulty in eating or kissing.  

Disorders of the TMJ are much less frequent than nerve injuries, but still make up nearly 15% of complications described after orthognathic surgery. Patients may suffer from joint dysfunction, disruption of the condylar surface, condylar resorption or malocclusion due to condylar sag. There is some controversy surrounding the benefits of orthognathic surgery in patients with existing TMJ dysfunction: some studies have reported a favourable outcome, while others show no effect or a worsening in function. However, there does seem to be a consensus that TMJ problems after surgery are more common in those who were already affected by the condition. A diverse range of TMJ symptoms has been reported following orthognathic surgery, including intra-articular noise, pain, clicking or grating and condylar resorption. Surgeons need to be particularly aware of the risk of this last condition in women, in whom the condyles tend to be smaller. As the condition may not develop for several years after surgery, long-term monitoring of the patient is necessary.  

All surgery carries a risk of haemorrhage and infection. The main risk of bleeding in orthognathic surgery comes from disruption of the descending palatine artery or, less commonly, from the maxillary artery. The probability of a serious bleed occurring appears to be related to the pattern of fracture of bony structures during surgery. However, life-threatening haemorrhage is extremely rare, with an incidence of <1%. Infections after surgery occur less frequently than haemorrhage and are often observed as maxillary sinusitis or abscesses. The location of plates and screws appear to affect the incidence of infection, and sinusitis may occur if mechanical drainage of the osteomeatal complex region is disrupted. Patients who are smokers or diabetics are also at increased risk. In rare cases, infection can occur several months after surgery, usually as a result of the body’s reaction to the fixation materials used.  

Hearing and auditory tube function may also be affected by orthognathic surgery. Some aural symptoms, such as tinnitus, fullness and pain, are consequences of the swelling and haematoma associated with surgery. Decreased auditory function can also result from scarring or other damage to the muscles that open the auditory tube and ventilate the middle ear. These conditions can take several weeks to fully manifest, and the incidence of hearing loss at 6–8 weeks after surgery varies widely, from 6% to 38%.   

Many legal cases brought after orthognathic surgery are due to the unrealistic expectations of the patient not being met. However, complications from surgery are not the only reason for an unsatisfactory outcome. Precise diagnosis is crucial, as is assessment of the patient’s aesthetic and functional issues. Surgical planning requires collaboration between the surgeon and the patient’s dentist and orthodontist to determine the exact procedure required for each individual patient. This, combined with continuous monitoring of the patient’s progress throughout treatment, should help to ensure a successful outcome.  

About Mr Sadiq

Mr Zaid Sadiq, is a Consultant Oral and Maxillofacial/Head and Neck Surgeon at the Queen Victoria Hospital prior to which he worked for many years at other leading hospitals including University College London Hospital and Great Ormond Street.

Mr Sadiq is qualified in both medicine and dentistry. He completed higher surgical training in Oral and Maxillofacial Surgery in the London KSS region. He completed a Head and Neck reconstruction fellowship in Edinburgh and is accredited by the Royal College of Surgeons of England.  He is an honorary lecturer at University College London.

Mr Sadiq has a keen interest in cancer, reconstructive surgery and tissue engineering, as well as providing a spectrum of oral and maxillofacial practice.

He can accept both adult and paediatric medico legal instructions. Find out more and download his CV here.

Further reading:  

Iannetti G, Fadda TM, Riccardi E, Mitro V, Filiaci F. Our experience in complications of orthognathic surgery: a retrospective study on 3236 patients. Eur Rev Med Pharmacol Sci. 2013 Feb;17(3):379-84. PMID: 23426542. 

Jędrzejewski M, Smektała T, Sporniak-Tutak K, Olszewski R. Preoperative, intraoperative, and postoperative complications in orthognathic surgery: a systematic review. Clin Oral Investig. 2015 Jun;19(5):969-77. doi: 10.1007/s00784-015-1452-1. Epub 2015 Mar 26. PMID: 25804886; PMCID: PMC4434857.