Yolanda Bernal participated in the Health Science Centerís study of rigid fixation. Doctors cut her jaw, repositioned it forward, and secured it with screws. The process spared Bernal from having her jaw wired shut for six weeks. Studies show rigid fixation not only improves jaw function, but boosts patientsí self-confidence as well.
Orthognathic surgery drastically improves a patient's life... A Health Science Center study drastically improves the procedure
by Aileen SalinasFor years, people with a shorter-than-normal jaw had only two options:
face surgery with an arduous recovery or endure the host of physical and psychosocial problems that accompany a severe mandible deficiency.
The surgical option was a procedure called orthognathic surgery. Surgeons cut part of the jaw, moved it forward and held it in place with wires. Doctors wired the patientís jaw shut for approximately six weeks while the bones healed.
An alternative procedure, called rigid fixation, used screws instead of wires to hold the bone in place. While rigid fixation was an option for patients, the procedure had not been tested in clinical trials. As result, no one was sure of its benefits. "Many surgeons were worried about the potential risks of using rigid fixation in orthognathic surgery," said John Rugh, Ph.D., professor and chair, department of orthodontics, and the studyís principal investigator. "Surgeons were concerned about an increased risk of temporomandibular joint (TMJ) disorder, surgical complication, infection and nerve damage."
In 1990, the Health Science Center launched a $2 million National Institutes of Health-supported collaborative research study comparing the two procedures. The results overwhelmingly supported rigid fixation. Emory University and the University of Florida also studied patients during the 10-year trial.
The perceived risks of the new technology did not occur more frequently in rigid fixation than wire fixation. Using rigid fixation meant jaws no longer had to be wired together, allowing patients to eat food and clean their teeth easier. And, most importantly, the study revealed rigid fixation to be very stable.
That is good news for the 15 percent of the population dealing with a mandible deficiency. Functionally, these people cannot properly chew food. Because of the jaw deformity, speech in extreme cases is impaired. Oral hygiene is compromised because teeth are pushed together.
Imbalances in oneís face also can affect mental well-being. Evidence reveals that people with a "weak" jaw are perceived as less attractive and less intelligent. They tend to receive lower grades in school, have less success in job interviews, and make less money. "These people have normal intelligence, but research shows they are not getting their fair share of life. The perception of others who rate these people daily can provide some fairly significant problems for them," Dr. Rugh said.
"It was well worth doing because of the facial and functional improvements. Itís a lot easier to eat now," Lea, a study participant, said. "I had a little numbness, but it faded. The sensation came back eventually."
Robert Lemke, M.D., D.D.S., clinical assistant professor of orthodontics
and one of the studyís co-investigators, found nerve damage from the two procedures to be about the same. Dr. Rugh reports that 60 percent to 70 percent of people are left with a little numbness on the lower lip, but most are not bothered. "The main positive outcome was stability of the result," said Dr. Rugh.
Screw fixation overwhelmingly was more stable and also proved to be more cost-effective than wire fixation.
Since screws sometimes torque or displace the bone segments, doctors worried they would affect the position of the jaw joint, which could cause TMJ disorder. However, the study found no more TMJ problems in screw fixation than in wire fixation. Quality of life also was not affected. There was no long-term difference in chewing ability. John Hatch, Ph.D., professor of psychiatry, reported that patient satisfaction was high in both groups and remained high for five years after surgery. Patients felt better about their self-image and showed significant improvement in self-image on psychosocial tests taken after the surgery.
"Their body image improves afterward. They might perceive their appearance as better because of all the positive feedback from peers," Dr. Rugh said.
"Some of these transformations are just extraordinary," said Stephen Milam, D.D.S., Ph.D., professor and chair of oral and maxillofacial surgery. "We have people who have been social isolates because of their appearance. After the surgery, they became very outgoing. Itís a complete life-changing experience
The Health Science Centerís positive results supported the surgeonsí increased use of rigid fixation. "There was no reason to turn back. We had such a great outcome," Dr. Rugh said. Rigid fixation is now a widely used method.
The collaborative study led by the orthodontics department also included the Health Science Centerís departments of oral and maxillofacial surgery, psychiatry, medicine, community dentistry and physiology. "Weíve always been involved in collaborative research, and this study crossed multiple disciplines. For example, we needed to study the physiological aspects of nerve and muscle and how patients rated psychologically, in addition to evaluating the oral health aspects," Dr. Rugh said. "The cumulative effort of all these departments provided quality research that betters our understanding and treatment of patients."
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