A good bite is dependent on the presence of matching upper and lower jaw bones in terms of size, shape and orientation. Jaw deformity occurs when there is an imbalance between the growth rate and potential of the jaw bones. The underlying reasons for this imbalance can be due to inheritance (genetics), disease (developmental), or facial trauma (acquired).
Affected individuals may complain of teeth that do not meet or match when biting, chewing disabilities, speech deficiencies, snoring with episodes of breathlessness during sleep (Obstructive Sleep Apnoea), excessive upper gum show, recurrent gum pain or cheek biting, protruding lower jaw (witch-like appearance), small lower jaw or absent chin (“bird-like” appearance) or crooked jaw (one side being larger or longer than the other).
Corrective jaw surgery is performed to restore normal chewing, speech and appearance. The surgery may involve one or both jaws depending on the severity and type of the deformity.
Benefits of surgery.
Correction jaw surgery can restore normal chewing function, facial proportions, speech and reduce episodes of breathlessness in patients with Obstructive Sleep Apnoea (OSA). Ultimately, correction leads to a better sense of both physical and psychological sense of well-being as well as self-esteem.
What will the doctor do?
The treatment often involves a multi-disciplinary team, consisting of a dentist, an orthodontist and an oral maxillofacial surgeon.
The attending specialists will carry out a detailed assessment of your bite, oral, facial and general health during the initial consultation. During the consultation, specialized investigations such as x-rays, moulds of your teeth and facial photographs may be taken with your consent. They will also spend time to understand your treatment expectations and provide you with information on the proposed treatment plan, including its benefits and risks. A joint consultation with other specialists and family members can be arranged should the need arise.
Your general dentist will be responsible for your general dental health throughout treatment. His role is to ensure that any existing dental or gum disease be brought under control and maintained during treatment.
Your orthodontist will prepare you for the surgery by aligning your teeth and matching the width of the dental arches. This phase usually takes between 9 months and 18 months. He is also responsible for putting the final touches to the way you bite post-surgery over a period of 6 months to 9 months.
Your oral maxillofacial surgeon will perform the corrective jaw surgery under general anaesthesia, usually in a hospital setting. The surgery can takes about half a day and may require a short hospital stay of between 2 days and 4 days to facilitate your recovery. Most patients will be encouraged to rest at home for the next 3 weeks to 4 weeks to complete their recovery. In complex cases, your surgeon may request for you to “store blood” if there is an anticipated need for blood transfusions during the surgery.
What is the experience like?
Like all patients undergoing braces treatment, you should expect initial soft tissue irritation and occasional tenderness affecting the teeth after initial placement and upon each activation appointment. Most patients adapt quickly to braces treatment within the first few weeks. The preparation phase will often make your condition to appear worse as the position of your teeth are normalized within their respective jawbones.
As the surgery will be performed under general anaesthesia, you will be asked to fast for at least 8 hours prior to the surgery. The incisions will be made inside your mouth and cannot be seen externally. The jawbones are subsequently repositioned to restore the bite and facial proportions. The bone segments are fixed in place using small titanium bone plates and screws. These bone plates and screws can be left in place for life as they are inert and biocompatible, although some patients may opt to remove them after complete healing has occurred.
What to expect after surgery?
Most patients will feel very sleepy post-surgery, experience a sore throat, nausea or nose bleeds due to the lingering effects of the general anaesthesia. You would also experience some degree of facial numbness and occasional bleeding from the surgical sites. Facial swelling and bruising becomes significant after 48 hours and ice packs can be used to reduce the swelling. The swelling may take 2 weeks or more to fully subside.
Your surgeon will prescribe analgesics to help manage discomfort and antibiotics to keep infection at bay. You can help keep the surgical sites clean by irrigating the wound area with antiseptic mouthwash using a syringe and brushing the outer surfaces of your teeth gently.
You will be on a liquid diet (e.g. milk, blended porridge, juices etc) for the first few weeks as your upper and lower teeth will be secured together tightly onto a bite plate using rubber bands. The rubber bands will be loosened gradually over the subsequent weeks, allowing you to gradually return to your normal diet. Due to these challenges, you should expect weight loss of between 2 and 5 kilogrammes during recovery.
Other challenges include the possibility of nose bleeds or stuffiness. Your surgeon may prescribe you nasal decongestants if you experience nasal symptoms. You can expect to resume work or school after about 3 weeks. It is however important that you abstain from heavy physical duty or exercises as a precaution.
Are there any risks involved?
Corrective jaw surgery is considered a major surgery with significant risks despite its benefits. It is usually performed in young adults who have completed facial growth. Some of the more common risks include:
The face, lip and mouth are richly innervated and surgery to this region carries a chance of nerve injury. This may present as numbness or a tingling sensation affecting the lips, chin, tongue, and gums. The incidence of permanent nerve injury is correlated to the difficulty of the procedure and varies between 10% and 15%. This also means that 85% to 90% of patients make an uneventful recovery.
Injury to roots of teeth.
The jaw bone contain the dentition and surgery to this area carries the risk of injury to the roots of the teeth, causing them to lose their blood supply. Follow up care such as root canal treatment may be required if this happens.
The surgical incision can become infected or open up to expose the underlying bone in the event of an infection. This is often managed using antibiotics, antiseptic mouthwashes and in some cases, a minor surgery to clean up or re-stitched the surgical wound.
Relapse of the corrected jaw position.
Relapse is the term used to describe the unwanted movement of the jaw bone towards its original condition, prior to corrective jaw surgery. This may occur immediately post-surgery or gradually over many months. Immediate relapse is linked to displacement of the jaw joint during surgery whereas delayed relapse is often caused by continued, unfavourable growth of the jawbones.
Discomfort during chewing.
The jaw joint between the lower jaw bone and the head is supported by a group of strong muscles and ligaments. Changes to the jaw position will require the patient to gradually adapt to their “new bite”. Patients who have a history of jaw joint dysfunction are advised to inform your attending specialists, as surgery may either relieve or aggravate the condition depending on the underlying cause of the dysfunction.
Severe bleeding post-surgery is an uncommon complication which may require blood transfusion or re-admission to the hospital.
Corrective jaw surgery have generated a lot of interest of late. The information provided above attempts to present the risk and benefits of surgery in a balanced and neutral manner. We recommend that you talk to a qualified specialist that you trust if you are considering surgery, as no one article can fully cover all the intricacies of such a complex treatment.