Surgical treatment to correct a bad bite

What does “bad bite” actually mean?

The term bad bite is a lay term for malocclusion. What that means is that the teeth of the upper jaw or maxilla do not align appropriately with the teeth of the lower jaw or mandible. A malocclusion can be limited to the teeth themselves and would be fixed commonly with orthodontic treatment or braces. A malocclusion can also be the result of misalignment of the jaws themselves. This can be either congenital, meaning from birth, developmental in nature, or from a traumatic injury. 

What kind of problems can having a misaligned jaw or malocclusion cause?

Common problems that result from a misaligned jaw or malocclusion include

• Difficulty with chewing or incising foods
• Speech difficulties
• Obstructive sleep apnea
• Temporomandibular joint problems (TMJ)
• Cosmetic disharmony in the smile and facial profile

What surgery is done to correct a misaligned jaw or malocclusion?

The surgery used to correct a severe malocclusion from a misaligned jaw is called orthognathic surgery. This includes procedures to move the upper jaw or maxilla forward, backward, or even to widen it. It also includes procedures to move the lower jaw or mandible rotationally to correct asymmetry, forward or backward.  Orthognathic surgery is usually completed in conjunction with orthodontic treatment or braces.

Most of the time your orthodontist will be the one to refer you to a surgeon to discuss jaw surgery. At times adjunctive procedures are completed to ensure symmetry and harmony of the facial profile, which can include chin surgery or genioplasty as well as cheek augmentation or malar implants.

Can braces do damage to the jaw?    

In general it is felt that orthodontic therapy is not specifically related to damage or problems with the jaw temporomandibular joints.

What types of materials are used in jaw surgery?

When considering orthognathic surgery the materials that are used to secure the jaws or maxilla and mandible into the new position are titanium plates and screws. They are very strong with a low profile so that they will not affect your appearance, but will maintain the new position of the bones during the healing phase. Due to the strength most of the time the teeth do not need to be left wired together after surgery.  The hardware or plates and screws that are used to position the jaws during surgery a most often left in place for life and are not removed.  

Is it possible for people to be allergic to these materials? 

In general, people are not allergic to surgical-grade titanium. That is not to say, however, that one could not be allergic to titanium though it would be very rare. 

What is the typical recovery time for jaw surgery?

Recovery after orthognathic jaw surgery is relatively rapid though may vary by patient and specific procedure. In general it will involve an overnight stay in the hospital with discharge in the morning or afternoon the day following your surgery. The diet is limited to liquids for the first few days, and is advanced to a non-chew diet for the first four weeks. A soft-chew diet is then gradually advanced to a normal diet after six weeks of healing.  

Though rare, if the teeth are wired together after surgery, a liquid diet would be required for six weeks after surgery.  Typically one week off of work or school is required after surgery. Activity is restricted for the first four weeks with no lifting greater than 40 lbs.  After four weeks, light activities can be resumed with low impact. Contact sports and rigorous activities can be resumed after 12 weeks or three months following surgery.  

How and when do you wire a jaw shut?

There are many ways to wire the teeth or jaws together. The term we use is maxillo-mandibular fixation or MMF for short. Though it is rare in conjunction with orthognathic surgery if required the orthodontic appliances or braces that the patient has on are used. Wires can be looped around the braces of the upper and lower teeth to wire the jaw shut.  

The jaw may be wired shut due to trauma or mandibular fractures as well in order to immobilize it. It may also be wired for reconstructive purposes.  This is typically done with either arch bars or Ivy loops.

An arch bar is a temporary brace that has hooks on it that can be secured to the teeth with wires.  Once in place on the upper and lower teeth, the hooks are used to loop wires around that are used to wire the jaw shut.  

Ivy loops are a variation on that technique that utilizes wires only without the arch bar.

Lastly, there are screw retained arch bars. This means that rather than securing the arch bar to the teeth with wires it is screwed into the bone of the maxilla and mandible. It too has hooks on it that can be used to loop wires around to wire the jaw shut.  

The functionality of wiring the jaws or teeth together serves to immobilize the bones while they are healing, therefore acting like a cast. We ask patients who are wired together to carry wire cutters with them in case they are involved in an accident. It is usually not necessary for patients to cut their own wires.

Why would you wire the jaw shut for orthognathic surgery?

With most orthognathic surgery or jaw surgery to move the maxilla and mandible, it is not necessary to wire the teeth together. Instead, we use titanium plates and screws as mentioned previously to secure the jaw into the new position. Occasionally, with very large movements or in the event of a less than ideal fracture the teeth or jaws may be wired together in order to immobilize the bones during the initial phase of healing. This is not very common.

Is wiring a jaw shut painful?

The use of maxillo-mandibular fixation or MMF is not painful. The use of local anesthetics, conscious sedation, and occasionally general anesthesia make the process quite comfortable. After the completion of the procedure there can be some discomfort with the wires in the mouth, though this is usually very minor and can be managed with wax in sharp areas, the same as for traditional braces or orthodontic appliances.  

With jaw surgery, are any scars visible?

When undergoing orthognathic surgery or corrective jaw surgery the majority of the incisions are hidden inside the mouth. The oral mucosa or gum tissue has an amazing capacity to heal and even intraoral scarring is minimal. Oftentimes, the application of the titanium screws in the mandible once in the new position, can require a small incision near the angle of the jaw. It is typically no larger than 2-4 mm and is usually not noticeable after three to six months. 

If I have a severe underbite or severe misalignment of my teeth, should I consult an oral and maxillofacial surgeon or a plastic surgeon?

If you are considering surgery for a severe misalignment of the teeth or jaws, first and foremost, you should visit an orthodontist.  Correction of a malaligned, underdeveloped, or overdeveloped jaw requires a combined effort, usually including an orthodontist and an oral and maxillofacial surgeon.

Oral and maxillofacial surgeons have special training that requires extensive knowledge of facial surgery as well as dentistry, which makes them well equipped to manage surgery involving correction of a bad bite while also considering overall facial harmony. I would recommend relying on your orthodontist for ultimate referral though seeking care initially from an oral and maxillofacial surgeon is reasonable as well. The surgeon will likely provide a referral to a local orthodontist.

What kinds of pain medications and antibiotics are normally prescribed to a patient after jaw surgery? 

Following jaw surgery, we typically prescribe a mild analgesic in combination with a non-steroidal anti-inflammatory drug or NSAID like ibuprofen. With upper jaw surgery, we often give a nasal decongestant to decrease swelling of the nasal mucosa. In regards to antibiotics, an intravenous dose is provided pre-operatively and is continued post-operatively until discharge on a regular schedule. On discharge from the hospital your surgeon may recommend a short course of oral antibiotics.  

Is there a lot of swelling from jaw surgery?

A moderate amount of swelling is expected with orthognathic surgery.  In order to limit the amount of swelling and improve patient comfort we utilize high-dose perioperative steroid administration. This includes an oral dose the evening prior to surgery followed by intravenous dosing in the operating room and post-operatively while in the hospital. The amount of swelling will vary from patient to patient. Typically after two weeks it is vastly improved and by four to six weeks it is 90 percent resolved.  It may take up to six months for the last 10 percent of swelling to resolve, though this is typically only noticed by the patient and close family.

What is the percentage of people who will experience an infection after surgery?

The incidence of infection following orthognathic or jaw surgery is very low. In the literature, the incidence is reported to be between 6 and 15 percent. These figures are high, in our opinion. When it occurs, the infection is easily treated with antibiotics and drainage with minimal discomfort and no long-term effects.

What can be done to prevent infection?

During jaw surgery, we utilize high-dose perioperative intravenous antibiotics for prophylaxis to prevent infection. Meticulous surgical technique and accomplishing the surgery in an efficient manner will also reduce infection rates. Occasionally, if bone grafts are utilized during surgery, we will continue the antibiotic therapy for seven to ten days orally after discharge. Our patients are also sent home with an antibacterial mouth rinse to help keep the wounds clean and are instructed on meticulous oral hygiene practices. Proper oral hygiene post-operatively is important in reducing the bacterial load in the mouth and adjacent to the surgical wounds.

Is there any long term follow up needed?

Following an orthognathic surgery, we have patients return for numerous postoperative visits in order to ensure proper healing. We typically see patients at one week, four weeks, six weeks, and 12 weeks following surgery. We also see the patient back at the six-month and 12-month intervals once the orthodontic therapy is complete and the braces have been removed. A final set of records is obtained at that time. Close post-operative follow-up is important in order to catch any possible complications early as well as to ensure the proper bite and jaw position has been obtained and is stable.  

What is JRA?

JRA stands for juvenile rheumatoid arthritis. It is very different from the adult form. It is often a diagnosis of exclusion meaning all other diagnoses are ruled out. It can involve the temporomandibular joints. If so, management typically involves a team approach not only including the oral and maxillofacial surgeon and orthodontist, but rheumatologist and other physicians as well.  

When it affects the temporomandibular joints JRA can lead to limited opening and malocclusion or a bad bite and misaligned jaws. It is often managed with newer medications typically guided by the rheumatologist. If the disease remains stable, then surgical correction of the bite can be undertaken by the surgeon and orthodontist with traditional orthognathic surgery. If the disease remains active and refractory to medical management, then total joint replacement of the temporomandibular joints may be necessary.    

Does a cleft lip/palate affect the jaws?

A cleft lip and/or palate is often associated with a cleft of the alveolus or the tooth bearing segments of the upper jaw or maxilla. The patient usually undergoes several surgeries in the area of the cleft at an early age. Because of this early surgery, the normal growth pattern of the maxilla can be restricted.

It is often necessary to advance the upper jaw when the patient is in the mid to late teens. This can be completed in a single surgery and may also be combined with a lower jaw or mandibular surgery.  At times, if the movement is too large to complete in a single surgery, a procedure called distraction osteogenesis may be undertaken to reposition the jaw. This procedure grows the jaw over a period of weeks to achieve the desired position. It is typically reserved for very large discrepancies.  

What is distraction osteogenesis?

Distraction osteogenesis of the jaws is based on the Ilizarov leg lengthening procedure. In many ways, it is more successful and reliable in the head and neck region versus the extremities because of the ample blood supply found in the head and neck. It is typically reserved for very severe deformities that cannot be corrected in a single surgery.  

In the mandible or lower jaw it is at times used to advance and grow the jaw forward in order to open the airway and avoid the need for tracheostomy in infants and children with severe micrognathia (small mandible).  

As mentioned previously in the maxilla or upper jaw it is often times used in patients who have undergone cleft lip and palate repairs, which can restrict maxillary growth. This can lead to a more severe misalignment of the jaws. Distraction osteogenesis can be utilized in these cases to grow the jaw over a period of time to correct a more severe discrepancy.  

The distraction osteogenesis procedure can take more time than traditional orthognathic surgery. During an initial surgery, devices are placed on the mandible or the maxilla. These devices are then turned twice a day by the patient at home, or in the case of infants by the surgeon in the hospital. This advances or grows the jaw by 1 mm per day. A typical advancement may range from 10-15 mm. That would require up to two weeks of turning. Once the growth is complete the devices are no longer turned and remain in place for about 6-12 weeks to allow the new bone to calcify and heal. After this period a second surgery is undertaken to remove the implanted devices.

One other advantage of distraction osteogenesis is that the soft tissue envelope meaning muscle and skin will readily follow the bone.  

What is the likelihood that you would lose sensation in your mouth after surgery?

Following orthognathic surgery, there will be neurosensory changes. The nerves involved with jaw surgery are not motor, meaning surgery will not affect how your face looks or moves. In the lower jaw, the numbness will include the lower lip, chin, and gum tissue, and in general, this should resolve in about three months. Sometimes neurosensory changes take up to 18 months in an adult to resolve completely.

Occasionally, minor neurosensory changes of the lower lip and chin can be permanent. Permanent numbness following an upper jaw (maxilla) surgery is much less common.