Orthognathic Surgery

Orthognathic comes from the Greek word “orthos,” which means straight, and “gnathos,” which means jaw. Orthognathic surgery is a set of surgical procedures used to correct jaw abnormalities resulting from skeletal problems.

This operation is an option for people with malocclusion (misalignment of the teeth) that cannot be fixed with orthodontics alone. Proper alignment of the teeth and jaws will improve your ability to chew and bite into foods as well as the appearance of your smile and facial profile. Common jaw abnormalities include:

Lower jaw problems

• A small or underdeveloped lower jaw may cause difficulty biting into food and/or breathing. Your upper teeth may jut out or overlap your lower teeth, causing your chin to look receded.
• A large or overdeveloped lower jaw may cause your chin to appear too far forward and your lower teeth may overlap your upper teeth, causing difficulty biting into food and chewing.

Upper jaw problems

• A small or underdeveloped upper jaw can cause your teeth to look receded.
• A long or overgrown upper jaw may cause your teeth not to overlap, and your smile may show mostly gums.

Uneven jaws

• The jaw can grow at different rates, causing jaw or facial asymmetry. Your face can appear off-center and your upper or lower teeth may shift to one side.

Oral and maxillofacial surgeons typically choose to correct these problems after your jaws have stopped growing. This usually occurs during late adolescence or early adulthood.

Jaw abnormalities can be caused by congenital (present at birth) defects, a genetic tendency for the jaws to grow at different rates, jaw injury or fracture, or a late growth spurt.

Jaws that are not properly aligned may cause the following problems:

• difficulty chewing food
• difficulty biting into food
• increased risk of teeth getting worn down
• breathing problems

While orthognathic surgery is quite involved and can sometimes include years of preparation, operations are successful in fixing jaw abnormalities and improving facial appearance.

Aligning your teeth before orthognathic surgery

Prior to the operation, an orthodontist will place braces on your child’s teeth. The orthodontist will move the teeth into the correct position during monthly adjustments. The surgeon will use the braces during the operation. Then, the braces will remain in place after the operation for a few months, depending on your child’s teeth and the type of operation.

Checking your progress before orthognathic surgery

Throughout the orthodontic treatment, progress records of your child’s jaw and teeth will be reviewed. Once operation is scheduled, your child’s surgeon will discuss the type of operation and expected outcomes with you.

Your child will be under general anesthesia. Depending on the type of operation and condition, the procedure can take anywhere from 2 to 8 hours.

There are different types of orthognathic procedures. The three most common ones are:

Bilateral sagittal split osteotomies (lower jaw surgery)

• The surgeon makes the incision inside the mouth usually behind molars. The jawbone is then cut and moved forward, back or rotated.

Le Fort I osteotomy (upper jaw surgery)

• The surgeon makes the incision inside your child’s mouth behind the upper lip. The jawbone is then cut and moved forward, back or rotated.

Genioplasty (chin surgery)

• The surgeon makes an incision inside your child’s mouth behind the lower lip. The chin is then cut from the lower jaw and moved forward, back, down, or rotated.

It is unlikely that your jaw will be wired together. Once the jaw is placed in its new position, it is secured with small metal plates and screws. In addition, elastic rubber bands are used to guide your new bite.

Your child may initially feel anxious after surgery because of a sore throat, clogged nose, lip numbness, and difficulty eating. It is important to help your child remain relaxed by helping him or her breathe slowly and deeply. Remember that the first week is the most difficult.

Pain and bleeding

• It is unlikely that your child will have severe pain following the operation because of the associated numbness. Some blood may ooze from the nose or mouth during the first 24 hours. Some slight nasal bleeding from the breathing tube is also possible.

Swelling and bruising

• There will be swelling and potentially some bruising after the operation. The swelling will typically be worst on the third day after surgery – and then will gradually lessen over the next few weeks. Most of the bruising will fade by the second week.

Numbness

• Some numbness of the lower and upper lips, nose and cheeks is normal for few weeks or months after surgery. Approximately 5 to 10 percent of patients will have permanent numbness in one or more areas. This ONLY affects the sensation of the lips, nose, chin, tongue, or cheeks. It DOES NOT interfere with movement of the face.

Eating

• During the first few days after the operation, you may use a flexible syringe to place food in your child’s mouth, because using a cup may be too difficult.
• The majority of patients must remain on a soft, non-chew diet for approximately 6-8 weeks.
  • Most patients average a seven- to 10-pound weight loss during this recovery phase.
  • Do not use this phase as a diet opportunity, since proper nutrition and calorie intake are critical for healing.

Speaking

• Speech may feel awkward because of the new position of the teeth and the numbness in your jaw. This will get better as the swelling decreases. You can have notebooks or a whiteboard at your child’s bedside for the first few days after surgery. However, it is important to encourage speaking, which will help aid in the healing process.

Initial healing of the jaws takes around six weeks, while complete healing of the jaws takes up to a year.

You will meet with your surgeon weekly during the first month. After about six weeks, your child will return to the orthodontist to begin finalizing his bite. Post-surgical orthodontic treatment can last up to one year. It is essential that your child follow the orthodontist’s instructions to get the best results.

The Oral and Maxillofacial Surgery Program at Boston Children’s Hospital offers comprehensive evaluation and correction of the upper jaw (maxilla) and lower jaw (mandible). Our highly experienced oral and maxillofacial surgeons are known locally and nationally.