ORTHOGNATHIC JAW SURGERY

About Orthognathic Jaw Surgery

Orthognathic Surgery corrects midface and jaw deformities specifically related to occlusion, or the way the teeth come together. The reason for this surgery is usually related to disproportionate growth, either in the maxilla (the midface bone containing the teeth) or the mandible (the lower jaw).

This surgery is usually performed in late adolescence, after the patient’s growth spurt has occurred, or in adulthood, since a child’s future growth can be unpredictable. It should be noted that this type of surgery is performed to correct functional growth deformities. It is not a cosmetic procedure and is typically covered by major medical insurance.

Various procedures can be performed in the area of Orthognathic Surgery. For example, it may be necessary to move the maxilla forward and down, and even to widen it if there is a growth deficiency in the midface. Also, the midface can be intruded vertically (shortened) if there is an overgrowth causing a smile that shows too much gingiva (gum tissue) and difficulty getting the lips together around the teeth.

Surgery in the mandible can involve advancement operations if the lower jaw has not grown enough, or set-back operations if it has grown too much. Set-back operations correct an underbite, a condition that occurs when the front teeth on the top are behind the front teeth on the bottom.

Orthognathic Surgery is usually performed in conjunction with orthodontic therapy. The purpose of the orthodontic therapy is to level and align the teeth so that once the surgeon moves the jaw bones, the teeth then fit together. Usually, in this pre-surgical phase of orthodontics, the malocclusion (improper tooth alignment) is made worse. The surgery moves the bones so the teeth fit together. Usually a period of post-surgical orthodontics is required after the surgery.

The Operation

The Orthognathic Surgery operation is performed in the hospital or in our state-of-the-art surgery center, Park Meadows Outpatient Surgery, depending on the extent of the surgery and the overall needs of the patient. The surgery is done using a general anesthetic with an endotracheal breathing tube passed through the nose, allowing the anesthesiologist to assist the patient’s breathing while he or she is asleep.

There may also be a nasogastric tube placed through the nose into the stomach to keep the stomach empty. This tube placement decreases the amount of post-operative nausea. Usually these tubes are removed before the patient is awakened at the end of surgery, but if there are concerns about potential nausea and if the patient’s teeth are wired together, the tubes may be left in place.

For surgery in the maxilla (upper jaw), an incision is made under the upper lip. The bone is exposed and the nasal passage is dissected along the floor and side walls. Then a cut is made in the bone, so it can be mobilized and repositioned. The maxilla is usually put into position with very small bone plates. Occasionally wires are used as well. These plates or wires are typically left in place unless they begin to bother the patient.

Surgery for the mandible (lower jaw) is performed by making an incision on the inside of the mouth. A bite block is used to protect the Temporomandibular Joints (TMJs). The incision is located back near the molar teeth. The bone is exposed and retractors are placed in the mouth.

The most common operation to advance or set back the jaw is called a Saggital Split Osteotomy, developed by a German surgeon named Dr. Hugo Obwegeser. The Saggital Split is made to protect the nerve that provides sensation to the lower lip running through the middle of the jaw. This type of surgery also allows for the placement of bone screws or plates, and the patient, therefore, does not have to have his or her jaws wired together at the end of the procedure. These screws are inserted into the jaw by making a small ¼ inch incision on the side of the cheek to allow the screw driver to pass through. The scars are usually very minor, like the scar of having a mole removed.

Another operation to set the jaw back does not allow for screw placement. Thus, the teeth must be wired together for at least 6 weeks following surgery. This is called a vertical oblique osteotomy, and the cut is on the back part of the mandible (lower jaw) in the vertical region called the ramus. In this case, there are no incisions on the outside of the face because screws and plates are not used.

The vertical oblique osteotomy seems to remain more stable over time with less chance of relapse (a return to the jaw’s original position) and carries less chance of numbness of the lower lip following surgery compared to the Saggital Split procedure. As mentioned before, however, the patient’s teeth must be wired together for 6 weeks after surgery.

Sometimes both the maxilla and mandible will require surgery simultaneously to correct fully the deformity. This “double jaw surgery” usually requires:

At least 1 day in the hospital.
The patient’s donation of autologous blood (his/her own blood) prior to surgery, in the rare event a transfusion is needed.

Jaw surgery to correct malocclusion (abnormal bite) may not be enough to fully correct the facial-skeletal proportions and lip competency (the ability to bring the lips together at rest without straining). Additional procedures might include chin surgery, nasal surgery, cheek bone augmentation (increase in size), liposuction (fat removal), and bone grafting. The surgery can take 1-1/2 to 10 hours depending on the difficulty of the operation and if additional procedures are done at the same time.

Recovery

Most patients do not have a great deal of pain following the procedure. Oral pain medication in liquid form is usually adequate. Most patients are dismissed within 24 hours; however, a few patients require 2 to 3 days of hospitalization.

One day after surgery, the patient may shower and begin to take fluids by mouth. Some oozing of blood may occur for the first 24 hours. Some patients may also experience a sore throat or some slight nasal bleeding from the breathing tube. Patients who had maxillary (upper jaw) surgery will have more nasal bleeding than those patients who only had mandibular (lower jaw) surgery.

The incisions are closed on the inside of the mouth with reabsorbing (naturally dissolving) sutures. These sutures usually dissolve in the first or second week after surgery. By this time, the incisions are healed, and any small openings that occur are usually not significant since the mouth heals so well at this point of recovery.

The edema (swelling) will be profound, usually at its largest on the third post-operative day. It will then respond to gravity and drop low in the cheeks and into the neck. With lower jaw surgery, some bruising on the neck and down onto the chest will occur in some patients. The bruising will transform from purple, to green, to yellow. Most bruising fades by the second post-operative week.

Some numbness of the lower lip is normal for the first six weeks following a Sagittal Split Osteotomy. Most patients have a normal return of sensation over the next several months. One note, however, 10 percent of these patients will have permanent numbness of one or both sides of the lower lip. This numbness does not effect the movement, just the sensation of the lip. Most patients adapt very well if this development occurs. The patient will be on a “non-chew” liquid diet for 6 weeks, whether or not your teeth are wired together, to allow the bones to heal without displacement.

Elastics may be used to guide the bite during the healing phase, if the teeth are not completely wired together. The usual routine involves wearing elastics all the time for the first two weeks, then wearing them all but four to six hours per day during weeks three and four. During post-operative weeks 5 and 6, the patient will wear the elastics only at night.

Each patient heals differently, so the surgeon might modify the treatment during the recovery phase to address your individual needs. The jaws might even have to be wired together, after all, to assure proper positioning.

Beginning the evening after surgery, you will start using a decongestant nasal spray, such as Afrin or Neosynephrine, to shrink swelling in the nose. The nasal spray is only recommended for 3 days because it can cause rebound swelling (initial shrinking then greater swelling). Ocean Spray, a saltwater spray, is very helpful and can be used as often as needed to help clear the nose of mucous and dried blood.

Most patients say they feel a little claustrophobic (confined in a space) because the throat is sore, the nose is partially clogged, and the teeth may be wired together. It is important to remain relaxed, breathing slowly and deeply, and remember that the first 3 days are the most difficult.

Since swallowing may be difficult at first, bedside suction helps to keep the mouth free of saliva. These small, portable units can be rented for home use in anticipation of surgery, and they are available at the hospital if you stay overnight. The lips will be dry and chapped from being stretched during surgery. This dryness usually lasts up to 2 weeks. Vaseline or some other type of lip balm helps. Apply as needed.

After about 6 weeks, the patient will return to the orthodontist to finalize the bite. Post-surgical orthodontic treatment can last up to 12 months. Retainers and positioners will be important, and following the orthodontist’s instructions will be essential to achieving the best results.

Speech will be difficult at first if the teeth are wired or held together with elastics. This difficulty will improve with practice and as the swelling goes down. In order to eat during the first few days after surgery, the patient will have to use a large syringe to inject the fluid diet into your mouth. Swelling will prevent normal chewing and swallowing, and using a cup will be too difficult at this phase. Once again, practicing this method of feeding will make it easier to eat. Most patients, however, average a seven to ten pound weight loss during the six-week recovery phase. Do not use this phase as a diet opportunity. Proper nutrition and calorie intake is critical for healing.

Complications

Most of these are rare, but you should be aware that surgery can be unpredictable. The possible complications include:

Bleeding.
Infection.
Nerve injury (permanent numbness of the lip, tongue, cheek, etc.).
Relapse or return to original jaw positioning.
Damage to teeth.
Scarring.
Temporomandibular (TMJ, or jaw joint) problems.
Nasal airway obstructions.
Non-union (inadequate closure) of the bone.
Sinusitis (swelling of the nasal sinuses).

Pre-operative Instructions

Do not eat or drink anything after midnight the night before surgery.
Wear loose, comfortable clothing on the day of your surgery. A button-down shirt is easier to manage than a pullover.
Take a daily multi-vitamin with iron, beginning 1 month prior to surgery.
Take 1,000 mg of vitamin C daily, in four 250 mg doses, beginning 2 weeks prior to surgery.
Arrange the necessary time off from work or school. Most patients will need 1 to 2 weeks of convalescence.
Bring a writing tablet to help you communicate after surgery.
Obtain a blender to help with the post-operative diet.
Arrange for both a suction unit and a humidifier. The humidifier helps keep the nasal passages moist and loosens dried blood.
Arrange for someone to care for you the first 48 hours after leaving the hospital or surgery center. This person may need to help you bathe, too.

Post-operative Instructions

Keep head elevated on 2 pillows for 2 weeks. This position aids in decreasing facial swelling.
Do not chew anything; your diet should be fluids only. For the first several days, use a
syringe that injects the fluid in your mouth. Take medications by syringe also. You may advance the diet as you choose, remembering to protect the operative areas. Adequate nutrition and maintaining body weight is important for recovery. Plan to eat small “meals” at least 6 times per day. Allow extra time at first.
Apply Vaseline to the lips, as needed.
Brush the teeth gently the first week with a soft toothbrush and your choice of toothpaste. Do not brush the gums until the second week. Always protect the incision sites until they are healed.
Use a decongestant nasal spray to dry up the oozing and open the nasal passages. Use this decongestant only for 3 days. Otherwise, rebound swelling may occur in the nasal tissues, making breathing more difficult.
Use a saltwater nasal spray, such as Ocean Spray, to break up any blood or mucous clots in the nose. This infusion can be done over the sink as often and in whatever amounts as desired.
Use a humidifier at night, aiming the vaporized water gently across the face to help keep the nasal passages moist.
Apply ice to the face for the first 24-36 hours to decrease the amount of swelling. After this time, it may be continued as a comfort measure, but is no longer necessary. Heat may be applied after 36 hours if it is comforting.
Do not use mouth washes containing alcohol, unless they are diluted in a 1:3 ratio with water, because the alcohol will irritate the incisions.
Rinse with warm salt water, either by cup or with the feeding syringe, beginning the day after surgery, and continue for 7 days. (Dilution: ½ teaspoon of salt in 1 cup of lukewarm water)
You may shower or bathe the day after surgery. Make sure that you can sit in the shower or have someone with you to steady you. After surgery, it is not uncommon to feel light-headed upon standing, especially while taking a warm shower. You may use regular soap and shampoo, even if there was a bone graft taken from the scalp or hip. If a hip graft was taken, then a shower is preferred so the donor site (site of bone removal) is not soaking in bath water. Cleaning after surgery will lift your spirits.
Do not lift anything over 10 pounds for 2 weeks. Contact sports should be avoided for at least 8 weeks. Make sure to ask you surgeon any other questions you might have regarding activity.
Avoid sun exposure and use a sunblock with at least a 20 SPF, since darkening of any incision on the skin can occur for up to six months.
If your teeth are held together with wires, keep wire cutters with you at all times.
Call your surgeon with any questions or if you experience any of the following: temperature is over 101.0F, excessive bleeding or rapid swelling occurs, pain is unrelieved by prescribed pain medications, breathing is difficult, you experience a sudden shift of the bite or bones.
Take one daily multiple vitamin with Iron and 1,000 mg of Vitamin C, in four 250 mg doses, for 6 weeks following surgery.