Novel Methods to Treat Treacher Collins Syndrome in Children

Treacher Collins Syndrome (TCS) is a genetic condition involving underdevelopment of the structures of the head and face. Part one discussed the work of Dr. John Teichgraeber, a plastic surgeon at The University of Texas-Houston Medical School and Dr. Jaime Gateno, a dentist and dental researcher at the UT-Houston Dental Branch, who have been working on novel methods for treating TCS.

Osteodistraction, or bone expansion, is a common corrective measure for children with Treacher Collins Syndrome. It has a long history. In 1905, a scientist by the name of Codivilla first described the concept of bone lengthening, and in 1927, the tibia was lengthened with a compressed spring. However, there was a high incidence of complication and the techniques were not widely accepted.

In the 1950s, Gavriel Ilizarov improved upon earlier methods, by straightening and lengthening extremity fractures. One millimeter a day was recommended for bone lengthening. Often, the mandible was resectioned, after the process of lengthening and widening the jaw was accomplished by distraction.

In the early 1970s, distraction techniques were practiced on dog mandibles, with the idea of applying this research to human patients who had congenital deformities. Besides Treacher Collins Syndrome, Nagers syndrome, Pierre Robin syndrome, and hemifacial microsomia were some of the other mandibular conditions ripe for improvement.

Children who have Treacher Collins Syndrome have multiple craniofacial challenges including breathing, hearing, cleft palate, cheekbone, and jaw anomalies. Medical progress in correcting some of these dentofacial complexities has been gradual.

By the late 1980s to early 1990s, conventional treatment involved extensive surgery and prolonged hospitalization (sometimes six to eight weeks). The teeth were normally wired together, bone growth and skin changes were unpredictable, with infection a constant threat.

Increasingly less invasive techniques utilizing mandibular distraction began to take ascendance in treatment. Working with the bone and soft tissues in their natural growth and healing process, doctors found that patients could maintain active lifestyles, results were more uniform, there was less chance of infection. Most importantly, techniques could be applied at a young age, with tissue healing quicker and less psychological impact.

"What Dr. Gateno does that's unique, I think, is customize these distractors," says Dr. Teichgraeber. "They're essentially moveable pieces and can fit the individual child's needs. It's minimally invasive, but maximally effective." He adds that four pins on each side of the jaw are normally inserted. They move a millimeter a day for an average of two to three weeks and are removed after six weeks.

"In our minds, it's the planning process that we do that's got the edge, and way ahead of what is commonly being done in the field today," says Dr. Teichgraeber. "If anything it's the hardware, the devices themselves, that are playing catch-up to our virtual reality program."

Dr. Teichgraeber believes that in the future, there will be implantable devices inside the mouth. They will be electrically activated or radially activated outside to provide the child with the dimensions needed to make the jaw look and react as nature originally intended. Right now, they're working on this idea, he says, with other scientists at Harvard School of Dental Medicine, department of oral and maxillofacial surgery, on a device they call the "roller coaster drive." Also, a prototype that Dr. Gateno has designed, a single pin in a mandibular plate, has real possibilities.

"We'll also use this three-dimensional computer simulation program to create our own distractors for other parts of the face. We may be able to simulate teeth for instance, especially for adult jaw movement. We may be able to spin-off commercial products or byproducts." Accepted for publication in the fall by the Journal of Oral and Maxillofacial Surgery is the authors' paper, "Accuracy of a New Protocol for Planning Distant Osteogenesis of the Mandible: An In-Vitro Study."

Dr. Teichgraeber says that on the drawing board are plans for an R&D Institute, with input from pediatric dentistry, pediatric orthodontics, plastic surgery, and oral surgery.

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©2006 Texas Medical Center

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