Orthognathic Surgery (Jaw Surgery)
INFORMATION FOR THOSE CONSIDERING CORRECTIVE JAW SURGERY
Orthognathic surgery is needed when jaws don’t meet correctly and/or teeth don’t seem to fit with jaws. Teeth are straightened with orthodontics and corrective jaw surgery repositions a misaligned jaw. This not only improves facial appearance, but also ensures that teeth meet correctly and function properly.
WHO NEEDS ORTHOGNATHIC SURGERY?
People who can benefit from orthognathic surgery include those with an improper bite or jaws that are positioned incorrectly. Jaw growth is a gradual process and in some instances, the upper and lower jaws may grow at different rates. The result can be a host of problems that can affect chewing function, speech, long-term oral health and appearance. Injury to the jaw and birth defects can also affect jaw alignment. Orthodontics alone can correct bite problems when only the teeth are involved. Orthognathic surgery may be required when bite problems cannot be corrected with orthodontic braces alone and require the repositioning of the upper and lower jaws.
DIFFICULTY IN THE FOLLOWING AREAS SHOULD BE EVALUATED:
- Difficulty in chewing, biting or swallowing
- Speech problems
- Chronic jaw or jaw joint (TMJ) pain
- Open bite (space between the upper and lower teeth when the mouth is closed)
- Protruding jaw
- Receding chin
- Inability to make the lips meet without straining
- Sleep apnea (breathing problems when sleeping, including snoring)
- Breathing problems
- Excessive wear of the teeth
- Unbalanced facial appearance from the front, or side
Any of these symptoms can exist at birth, be acquired after birth as a result of hereditary or environmental influences, or as a result of trauma to the face. Before any treatment begins, a consultation will be held to perform a complete examination with x-rays. During the pre-treatment consultation process, feel free to ask any questions that you have regarding your treatment. When you are fully informed about the aspects of your care, you and your dental team can make the decision to proceed with treatment together
TECHNOLOGY & ORTHOGNATHIC SURGERY
Dr. Benjamin Foley and Dr. Thao Le use modern computer techniques and three-dimensional models to show you exactly how your surgery will be approached. Using comprehensive facial x-rays and computer video imaging, we can show you how your bite will be improved and even give you an idea of how you’ll look after surgery. This helps you understand the surgical process and the extent of the treatment prescribed. Our goal is to help you understand the benefits of orthognathic surgery.
If you are a candidate for corrective jaw surgery, Drs. Benjamin Foley and Thao Le will work closely with your dentist and orthodontist during your treatment. The actual surgery can move your teeth and jaws into a new position that results in a more attractive, functional, and healthy dental-facial relationship.
WHY CORRECT A BITE DISTURBANCE?
The ideal bite is characterized by the simultaneous contact of all the teeth in a defined manner when the teeth are brought together. This simultaneous contact of all teeth equally distributes forces among all of the teeth. In those instances where only a few teeth contact, the teeth that receive the major portion of the forces will be jeopardized by excessive wear or excessive deterioration of the bone that supports the roots of these teeth. Though we as doctors do not have a “crystal ball” through which we can see the future for any patient, we can, with some degree of accuracy, characterize certain bite problems as being ultimately adverse to the long term retention of teeth. To some patients little importance is placed on properly functioning teeth. These individuals quite often end up losing all of their teeth and wearing complete dentures. To other individuals the teeth represent a very important part of their body and a comfortable, functional bite is important. Certainly, we cannot argue that teeth are necessary to maintain life. However, teeth that are healthy, pain free, and functional enhance the quality of an individual’s life.Most skeletal bite problems are manifested externally by a facial asymmetry, poor facial balance, or a patient may have difficulty bringing the lips together (lip incompetence). Though the primary goal of corrective jaw surgery is to establish a normal bite, simultaneous correction of an associated facial deformity may improve self-image and contribute positively to one’s quality of life.
CORRECTIVE JAW SURGERY CONSULTATION
This is intended to give you information about corrective jaw surgery. It is hoped that it will answer many of the common questions regarding surgery. Your consultation visit will consist of an examination and possibly one or more x-rays. We will review your photographs and dental models provided by your orthodontist. The goal of the initial visit is to begin assessing your treatment needs and develop a preliminary treatment plan. A second consultation visit will be scheduled at which time the surgical plan will be finalized and associated consequences, risks, and possible complications will be discussed. Additional radiographs and impressions for surgical models may be taken in preparation for surgery. You will have an opportunity to have your questions answered. The goal of the second consultation is to provide information that will allow you to make an informed decision regarding your treatment needs and finalize the surgical plan.
Corrective jaw surgery (orthognathic surgery) is well established. Many of the surgical procedures were developed in Europe as early as the 1920’s with major advances made in the 1960’s. Corrective jaw surgery was introduced in the United States in the late 1960’s. These operations are now very commonplace both in the United States and Europe. Managed care health care plans have denied many patients benefits for the correction of jaw deformities/bite abnormalities. You should inquire about your particular insurance benefits before you begin any treatments. I will assist you in securing insurance benefits by providing your insurance carrier clinical information regarding any proposed surgery.
JAW SURGERY AND ORTHODONTICS
The treatment of most bite abnormalities (malocclusion) is usually accomplished by orthodontics alone. Surgery is necessary when an abnormality in the position, shape, or size of the jaws prevents bite correction by orthodontic tooth movement alone. Surgery may be desirable in situations where the bite problem could be improved by orthodontics alone, but the results would be unstable or would be unsatisfactory, functionally and/or aesthetically. As abnormalities of tooth position and jaw deformity usually co-exist, it is usually necessary to combine surgery and orthodontics to achieve an acceptable treatment result
SEQUENCE OF TREATMENT
Bite correction usually begins with pre-surgical orthodontic treatment to optimize tooth position and alignment. The goal of the pre-surgical orthodontic treatment is to optimize tooth positions in anticipation of repositioning of one or both jaws for bite correction. The orthodontic appliances (braces) are not removed at the time of surgery. Progress study models of your teeth will be obtained to determine when you are ready for surgery. This determination will be made by your orthodontist and me. After completion of the pre-surgical orthodontic phase surgery will be scheduled. Six to 8 weeks after surgery, finishing orthodontic treatment will be initiated.
Treatment planning will be carried out jointly by your orthodontist and me. Your treatment plan may also be coordinated with your family dentist, physician, periodontist, or other doctors. Records such as dental and facial x-rays, dental casts, and photographs will be used as aids in this planning. No treatment will be started until you and, where applicable, family member(s) are fully informed and comfortable with the proposed treatment plan. If at any time in the treatment sequence, you have questions, please bring these to the attention of me and/or your orthodontist.
It is generally necessary to align the teeth orthodontically prior to corrective jaw surgery. This may require that braces be worn from a few months to a year or more prior to surgery. Periodically during the pre-surgical orthodontic phase plaster progress study models of your teeth will be obtained to determine when your teeth are in the proper position to undergo surgery. These progress models will be obtained by the orthodontist or me. In either case, however, your doctors will confer regarding the models and a decision will be made relative to the status of the pre-surgical orthodontic preparation.
The surgical phase of your treatment includes the corrective jaw procedure(s) and post-operative care. When progress study models demonstrate that you are orthodontically ready for surgery, the initial treatment recommendations will be reviewed, a final surgical treatment plan formulated, and a time for hospitalization to perform the surgery will be arranged. Corrective jaw surgery requires a brief hospitalization and is performed in an operating room with the patient asleep under general anesthesia. The period of hospitalization is generally 1-2 nights. Some lower jaw operations may be done on an outpatient basis, however most patients will stay overnight and be discharged on the first day following surgery.
I will see you on a regular basis following surgery. The first follow-up visit will be 1 week after surgery with subsequent visits approximately every 2 weeks until complete healing at 6-8 weeks. To evaluate long-term stability, it is my practice to see my patients after the orthodontic appliances have been removed and yearly for at least 2 years.
POST- SURGICAL ORTHODONTIC TREATMENT
Your orthodontist will begin the finishing phase of orthodontic treatment approximately 6-8 weeks after surgery. Two to 6 months may be required for the finishing orthodontic treatment. The period of finishing orthodontic treatment consists of final adjustment of tooth positions after which the orthodontic appliances will be removed. The orthodontist will place retainers that should be faithfully worn indefinitely.
SPECIFIC CONSIDERATIONS WITH CORRECTIVE JAW SURGERY
- SCARS: Corrective jaw surgery is generally performed entirely inside the mouth; therefore, no external scars are produced. Occasionally, a very small (less that ½ inch) neck incision is required for placement of jaw screws to stabilize bone fragments. These incisions will leave a scar that generally is cosmetically acceptable. I make these incisions on less than 10% of my patients. Irritation of the corners of the mouth always occurs with corrective jaw surgery. This appears as an abrasion and may actually form a scab. Noticeable scarring from this irritation is uncommon. If you will be undergoing a bone graft at the time of the corrective jaw surgery you should anticipate a scar approximately 2 inches in length in the region of your iliac crest. I will show you the location of this anticipated scar if a bone graft is planned.
- JAW FIXATION (IMMOBILIZATION): Your jaws may be wired closed in a predetermined position at the time of surgery in order to allow healing to proceed satisfactorily. The period of jaw immobilization is generally for 1-3 weeks. During this period you will only be able to consume liquids. All medications that I prescribe will be in a liquid form. Any regular medications that must be taken in pill form may be crushed and taken with liquid of your choice. After the wires holding your mouth closed are removed, you will be shown how to wear orthodontic elastics. Elastics will be worn approximately 23 hours/day until you are 6-8 weeks out from surgery. You will have the freedom to remove the elastics at mealtime. Especially after surgery to advance a short lower jaw, your lower jaw will be temporarily stiff and your ability to open your mouth limited. Jaw opening exercises will be started approximately 4 weeks after surgery. It usually takes several weeks of active exercises to regain most of the jaw opening.
- SPEECH: Clear speech is more difficult with the jaws wired closed. Patients differ in their ability to speak following jaw surgery. Typically patients will soon be able to communicate in person, although telephone conversations may be slightly more difficult. After surgery you should express your needs by talking as much as possible, not by writing notes. You will be biting into one or more acrylic wafer(s) while you are wired closed. This wafer (s) is fabricated prior to surgery and placed at the time of surgery to ensure proper bite alignment. The wafer (s) will make speech more difficult. Generally, the wafer(s) is removed 2-4 weeks after surgery.
- DIET: During the time that you are wired closed, your diet will consist only of liquids. Dietary instructions as well as samples of high calorie/high protein liquid diet supplement will be provided preoperatively. For the first 24 hours after surgery, you will be restricted to clear liquids (tea, apple juice, Sprite, etc.). After the first 24 hours, you will be encouraged to drink a high-calorie, high-protein liquid diet. After you begin elastic use, your diet will be advanced to very soft foods that do not require chewing. You should not chew until at least six weeks after surgery. You should be able to resume an unrestricted diet by 8 weeks after surgery. A 5-10 pound weight loss can be expected during the first two weeks, and after this time you should be able to maintain your weight. Loss of appetite after surgery is common and, apart from the jaws being wired closed, will contribute to early weight loss. Usually by one week after surgery the appetite will improve to the degree that most patients can maintain or possibly gain weight. Not withstanding concerns regarding calorie intake and weight loss, it is very important to take in an adequate volume of liquids during the first 5-7 days after surgery. Dehydration can and must be prevented by consuming at least 1-2 liters (the volume of 3-6 cans of soda pop) of liquid each day.
- SWELLING AND BRUISING: Facial swelling should be expected after corrective jaw surgery. Bruising is less common. The amount of swelling is variable, depending on an individual patient’s response to surgery and the type of surgery performed. Maximum swelling is generally reached within 72 hours of surgery. The majority of the swelling can be expected to subside within 1-2 weeks. Some mild residual swelling may persist for several months. Ice packs will be used immediately following surgery, and patients are routinely given special medicines intravenously prior to, during, and after surgery to reduce the tendency to swell. You will be instructed to keep your head elevated above the level of your heart at least for the first 3 nights after surgery. This can be accomplished by sleeping on at least 2 pillows or in a recliner chair. Occasionally I will place a drain tube(s) into a wound to diminish the accumulation of blood in the tissues. Such a drain tube(s) will exit the wound through the skin below your chin. Most drains can be removed at bedside the day after surgery. Despite these efforts some patients will have a great amount of swelling, especially involving the lips.
- PAIN: Patients are justifiably concerned about pain after jaw surgery. Most patients have only moderate pain after corrective jaw surgery. Low grade “discomfort” is common and responds well to pain medication. A few patients will describe severe pain, and this is likely due to differences in individuals’ pain tolerance. As a routine, a prescription for liquid pain medication will be provided after surgery. Patients who require a bone graft will experience a significant amount of hip pain for several days and soreness for 4-8 weeks. Prolonged, low-grade, intermittent discomfort from the donor site is occasionally described by patients who have had a bone graft harvested from the hip. An occasional patient will complain of jaw joint (TMJ) pain after surgery. Surgery to advance the lower jaw is more often associated with joint pain. This pain suggests to me that the joint(s) is being loaded during the time that the jaws are wired closed. This pain usually subsides but in rare circumstances may persist for weeks or months after surgery.
FACTORS RELATING TO SPECIFIC AREAS OF CORRECTIVE JAW SURGERY
THE FOLLOWING INFORMATION SHOULD BE READ SELECTIVELY DEPENDING ON THE PARTICULAR CORRECTIVE JAW SURGERY PLANNED. IF YOU DO NOT YET KNOW THE SURGICAL PLAN YOU SHOULD AT LEAST “SKIM” THE ENTIRE SECTION. ONCE A FINAL SURGICAL PLAN IS MADE YOU SHOULD CAREFULLY RE-READ THE SPECIFIC SECTIONS THAT APPLY TO YOU.
UPPER JAW SURGERY (LE FORT OSTEOTOMY)
When surgery is carried out to reposition the upper jaw in one, two, or more pieces, a semi-circular incision is made in the gum tissue beneath the upper lip. The significance of this incision is that the gum tissue immediately beneath the incision (i.e. towards the necks of the teeth) will have decreased or no sensation for several months after surgery. This incision will leave a scar that is not of any cosmetic consequence because it is concealed behind the upper lip. Upper jaw surgery involves a horizontal cut (osteotomy), made above the roots of the upper jaw teeth such that the upper jaw can be moved to a new position. Bone cuts may also be made between tooth roots if the upper jaw must be divided into two or more segments (pieces) for optimal bite correction.
NERVE DAMAGE/ALTERED SENSATION/NUMBNESS
In the process of cutting the upper jaw above the root tips the many small nerve fibers that run to the teeth themselves will be severed. As a result of this, the upper teeth will loose some or all of their sensation after surgery. Usually within 6 to 9 months the teeth will regain normal or near normal sensation. It is possible that a tooth or several teeth will remain without sensation permanently. Additionally, nerves that supply sensation to the palate (roof of the mouth) may be bruised to the extent that there may be numbness following surgery. In most instances numbness of the palate lasts two to six months. There are also two nerves that emerge from beneath the eye sockets that provide feeling to the skin over the cheeks and upper lip. Occasionally with retraction of the soft tissues during the upper jaw surgery, these nerves, one or both, may be bruised. Such bruising will produce some degree of loss of sensation in their distribution (cheek skin and upper lip). This tends to be the first nerve area to regain its sensation after surgery. Rarely loss of feeling in this area can be permanent.
DEATH OF TEETH/BONE
In cutting above teeth or between teeth, there is a risk of damage to one or more teeth. It is usually possible to avoid cutting the roots of the teeth. In the usual patient, cutting 5mm. above the root tips of the teeth will not cause the pulp within the tooth to die. Certainly, cutting between teeth places the teeth on either side of the cut at risk for damage. If a tooth is damaged, it would not be anticipated that such a tooth would be lost, but that a root canal treatment(s) would be required in order to prevent infection and to ultimately preserve the tooth. Tooth loss, however, is a possibility. As the surgeon and orthodontist arrive at a treatment plan, it is our intention to minimize surgical procedures that would involve greater risks to the teeth themselves. In those instances where the surgeon decides to make a cut(s) between teeth, it has been determined that the risk of tooth damage/loss is justified in the overall consideration of the potential gains in bite correction. I do not wish to ever have a patient lose a tooth or teeth through this complication. However, lost teeth can generally be replaced with a satisfactory prosthetic equivalent and this complication should not be a catastrophic event. Apart from the risk of direct tooth damage from the bone cut(s) there is also a risk of tooth and adjacent bone and gum tissue death and loss caused by inadequate blood supply to the upper jaw after the jaw has been mobilized and repositioned. Fortunately this is an uncommon complication. This problem may be recognized at the time of surgery, but more often will become apparent in the days to few weeks following surgery. I consider the risk of this complication greater in those with an underlying cleft lip and/or palate birth defect. This complication will most likely effect the anterior teeth and associated bone. To date, I have never experienced this complication but it is well described in the literature.
SURGERY TO POSITION THE LOWER JAW FORWARD (SAGITTAL SPLIT OSTEOTOMY)
Surgery to position the lower jaw forward is carried out near the angle and the vertical part of the lower jaw, behind the last molar tooth. This surgery involves splitting the jaw in such a fashion that the jaw is lengthened without creating a discontinuity or gap. As with upper jaw surgery this procedure is accomplished through incisions in the mouth. As a consequence of splitting the lower jaw, the nerve that passes through the lower jaw will be bruised. Bruising of this nerve will result in some degree of altered sensation in the lower teeth, the gum tissue around the 3- 4 lower front teeth, and the lower lip, and chin. The nerve on the left, the right or both will be bruised. In some instances there is no loss of sensation, but the patient must be prepared to have at least temporary numbness as a result of having the jaw moved forward. In looking at many patients, I have seen all degrees of change in sensation. I have also had a few patients referred to me with painful numbness (burning sensation) after undergoing this surgery elsewhere. Importantly, it is possible to have some degree of permanent sensation loss/alteration after this surgery. If a patient cannot accept the risk of numbness then he/she should not undergo surgery to have the lower jaw advanced. Finally, and fortunately rarely, the nerve that supplies sensation (including taste) to the tongue, may be bruised. This will lead to some numbness or other alteration of sensation on one or both sides of the tongue. This numbness too may be permanent.
Also in the lower jaw, surgery may occasionally be done beneath the lower front teeth. This surgery may be carried out to reposition the teeth in an upward or downward direction or to move the chin (genioplasty). Access is gained by an incision in the gum tissue behind the lower lip. The gum tissue above this incision will be numb for some period of time. Also, numbness of the lower front teeth may be experienced. Though this numbness may be permanent it, generally, is well tolerated. Temporary chin numbness is very common after genioplasty. Operating inside the lower lip may also produce lip numbness, as described above for lower jaw forward surgery. Though an unlikely complication, this numbness can be permanent.
SURGERY TO MOVE THE LOWER JAW BACKWARDS (VERTICAL RAMUS OSTEOTOMY)
This procedure is also accomplished through incisions in the mouth. The lower jaw is moved backward by making a vertical cut through the vertical portion of the lower jaw. This cut allows overlap of the bone as the jaw is shortened. Therefore, no bone must be removed to effect jaw shortening. In contrast to lower jaw forward surgery, the jaw is cut in such a way that the risk of injury to the nerve that runs through the lower jaw is small. Nevertheless, numbness/altered sensation in the lower gum tissue, teeth, lip and chin can occur. In rare circumstances the nerve damage may be permanent. As noted with lower jaw forward surgery, tongue numbness can occur but is an infrequent complication.
GENERAL RISKS ASSOCIATED WITH CORRECTIVE JAW SURGERY AND GENERAL ANESTHESIA
THE FOLLOWING SECTIONS SHOULD BE READ BY ALL PATIENTS CONSIDERING ANY TYPE OF CORRECTIVE JAW SURGERY
There are certain consequences and risks associated with any surgical procedure and anesthetic. Some of the consequences and risks associated with specific corrective jaw surgery procedures have been discussed. A patient must decide whether the consequences and especially the risks associated with undergoing corrective jaw surgery are reasonable in relation to the problem they wish to have corrected. My role as the surgeon is to help the patient make this decision by providing enough information such that a knowledgeable patient can critically evaluate and compare the risks and benefits of the treatment. If there are any aspects of the proposed treatment that you do not understand it is important that you discuss these concerns with me. It is my wish to never subject a patient to any surgery without their complete understanding of the proposed treatment-please ask questions. The complications that I feel patients should know about in reaching a decision with regard to treatment of their bite problem are complications that have been observed from time to time in a large number of patients. Patients should remember that no two individuals are exactly alike and though surgical procedures from patient to patient may be similar, seldom are they exactly the same. Individual patient responses to surgery vary as greatly as do the bite abnormalities of the patients treated. Along with the surgery-specific complications described above, the following risks should be carefully considered in your decision to pursue corrective jaw surgery.
EXTRAORDINARY BLOOD LOSS/BLOOD TRANSFUSION
In the normal course of events for patients who undergo surgical repositioning of the upper jaw or both jaws, blood transfusion may be necessary. Patients undergoing upper jaw surgery will usually have their blood pressure deliberately lowered by the anesthesiologist to decrease blood loss. You will be given the option to donate 1-2 units of their own blood prior to surgery. Rarely, there can be extraordinary, life-threatening bleeding with corrective jaw surgery such that blood in excess of that pre-donated might have to be transfused. Though blood-banked blood is carefully screened for infectious diseases, no blood is entirely safe for transfusion. If you are opposed to a blood transfusion you must discuss this with me before surgery.
Fortunately, infection with corrective jaw surgery is not common. Antibiotics are used around the time of surgery to minimize the risk of infection. Rarely, a sinus infection will result from upper jaw surgery. It is possible for a patient to develop an infection of such severity that hospitalization would be necessary for optimal management of the infection with I.V. antibiotics and possibly surgical drainage.
Relapse is that tendency for a tooth that has been moved by orthodontics or a jaw that has been moved with surgery to return to the pre-treatment position. Probably in all instances of orthodontic treatment and corrective jaw surgery there will be some relapse. It is anticipated that with the knowledge available today to help the surgeon and orthodontist correctly diagnose most problems and suggest proper treatment, major relapse will seldom pose a problem. Relapse is more likely in situations where open bite and and/or a short lower jaw is being corrected in the setting of jaw joint (TMJ) disease. There is tremendous variation between patients and surely as we continue to see patients and perform surgery for jaw/bite deformities, from time to time we will see exceptions to patients’ usual response to treatment. Pronounced relapse after corrective jaw surgery is such an exception. It is my desire to not have to re-operate on a patient as a result of unacceptable relapse. However, in the case of significant relapse, repeat corrective jaw surgery may be necessary. Thus far, I have re-operated on one patient with exceptional relapse following corrective jaw surgery. A second patient declined re-operation in spite of significant relapse. In both cases, surgery was directed towards the correction of significant lower jaw deficiency and open bite. Though there have been a small number of other patients with some degree of relapse the relapse was not of a magnitude where additional surgery was required.
TMJ SYMPTOMS (PAIN, CLICKING, POPPING, LOCKING, ETC.)
Corrective jaw surgery is rarely undertaken to improve jaw joint (TMJ) symptoms or function. TMJ symptoms that predate corrective jaw surgery may remain the same, improve, or worsen with corrective jaw surgery. Some patients with pre-existing TMJ disease will experience new symptoms at some point after corrective jaw surgery. Fortunately, this is not a common occurrence. For reasons that are incompletely understood, corrective jaw surgery may hasten pre-existing TMJ deterioration. This may occur without pain or other symptoms. However, in the patient who has had a severe open bite or short lower jaw corrected, such joint deterioration may cause exceptional relapse. I have never seen this deterioration occur in a patient who did not come to surgery with already advanced joint deterioration. Unfortunately, we do not have as much control over this problem as we would like to have. Patients with pre-existing TMJ disease, even if symptom-free, should have a clear understanding of this potential problem
Reproduced with permission by: Samuel J. McKenna, D.D.S., M.D., F.A.C.S.
Any other use or duplication of this material by any other party requires the prior written approval of Samuel J. McKenna