Jaw misalignment and orthognathic surgery

What does jaw misalignment mean?

Sometimes the bones of the upper and lower jaw do not match in size or position. University Hospitals Bristol and AAOMS list signs that may point back to this problem:

• difficulty biting, chewing or swallowing,
• chronic jaw or joint pain,
• heavy wear on the teeth,
• constant mouth breathing or closing the lips with effort,
• sleep apnea, which means pauses in breathing during sleep,
• teeth that do not meet (such as an open bite),
• a face that is unbalanced from the front or in profile, a lower jaw and chin set back, or a jaw that sits forward,
• differences present from birth, including cleft lip and palate,
• a jaw that does not sit right after an injury.

None of these signs alone means surgery is needed. Diagnosis is by examination and imaging. To learn about the images, see the guide to jaw imaging.

When is jaw surgery considered?

Cambridge University Hospitals writes that when the bones of the face and jaw are out of balance and orthodontics alone cannot correct the teeth, surgery is recommended. AAOMS also says the orthodontist and the oral and maxillofacial surgeon decide together whether the patient is a candidate. The surgeon chooses the technique and performs the operation. So the patient usually comes with a referral from an orthodontist, and treatment is teamwork.

The treatment path

University Hospitals Bristol calls it a “big commitment” that includes long orthodontics and major surgery. The path is usually this:

• Assessment. Examination, imaging and a talk about expectations, with both specialists.
• Braces before the operation. The orthodontist prepares the teeth for their new position. Cambridge University Hospitals does not state how long this takes.
• Surgery. Under general anesthesia. Cambridge University Hospitals writes that the operation is done almost entirely from inside the mouth so that scars are not visible. The bone is cut with a small saw, moved, and held with tiny titanium plates and screws. The gum stitches dissolve by themselves. If only the chin is operated on (genioplasty), the cut is inside the lower lip.
• Hospital stay. Most patients stay one or two nights.
• Braces after the operation. Sometimes elastic bands are attached to the braces so the bite settles into its new position. Cambridge University Hospitals says that, rarely, the bite does not come out fully right and a second small operation is needed.
• Follow-up. You are usually under the surgeon and orthodontist for up to two years.

Recovery

Cambridge University Hospitals writes:

• Swelling and discomfort. The face feels tight and swollen, the jaw stiff, and the mouth does not open easily. Discomfort is greatest in the first few days and lasts up to about two weeks. Swelling is greatest on the second or third day. Cold compresses and sleeping with your head raised help. Most swelling goes within two weeks, but mild swelling may last for months.
• Nose. After upper jaw surgery the nose may be blocked and you may have to breathe through your mouth. Swallowing may be difficult at first.
• Food. Liquids for a day or two, then soft food, and normal food in about four to six weeks. See the guide to eating after surgery.
• Work and activity. Usually about three weeks off and no heavy exercise. Do not drive for up to 48 hours after a general anesthetic. No contact sports for up to two months.

Some patients feel low or flat in the first days. This is normal and you should tell the treatment team.

Risks and complications

• Numbness. After surgery on the lower jaw or chin, the lower lip is numb and tingles. This is very common in the first weeks, and most patients gradually improve. Figures for one year after surgery differ: Cambridge University Hospitals says fewer than one in a hundred, a systematic review about 13 to 18 percent, and a 2026 study about 5 percent. It may be permanent.
• Bleeding. If the mouth bleeds, Cambridge University Hospitals says to press with a clean cloth or gauze for at least ten minutes. After upper jaw surgery a slight bleed from the nose may continue for up to about a week.
• Infection. The plates usually stay for good. Infection is rare and usually shows up months later. Sometimes a plate has to be removed.
• Imperfect bite. Sometimes the bite does not settle properly and a second operation is needed.
• Anesthesia. Nausea, sore throat, a blocked nose and dizziness are common, and a serious problem is uncommon.
• Change in appearance. University Hospitals Bristol warns that the change in the face can be large and that getting used to it takes time. The same hospital writes that most patients report better health and well-being, but this outcome is not a certainty for you.
• Speech. In patients with cleft lip and palate, speech may change.

If you smoke, Cambridge University Hospitals asks you to stop before the operation.

Questions to ask before deciding

Is there a way without surgery, and how would the result differ? How long does the whole path take, with braces before and after the operation? Which jaw or chin will be operated on? How likely is lip numbness in my case? How will my face change? If my jaws are held shut with elastics or wires, what do I do if I vomit or cannot breathe easily? The surgeon and orthodontist should give clear answers.

When to act urgently

• Tell the treatment team the same day about fever, swelling that gets worse after the first days, pus or a bad smell in the mouth. These may point to infection or a healing problem.
• Difficulty breathing, being unable to swallow your saliva, new or spreading swelling of the floor of the mouth and neck, and heavy bleeding that does not stop with pressure are emergencies. Call 115 and look at the list of urgent signs.

This page is for general information and does not replace an examination.