A MAN who lost his jawbone to cancer has enjoyed his first solid meal in nine years after having a new bone grown under his shoulder blade and then transplanted to his face.
For the groundbreaking operation, detailed tomorrow in the medical journal The Lancet, doctors made a Teflon mould of the jaw replacement using CT scans, which produce 3D X-ray images, and a computer-operated milling machine.
A titanium mesh cage was then constructed around the mould, removed and filled with bone mineral blocks, genetically engineered human bone protein and bone marrow taken from the patient.
Next the cage containing the raw ingredients of the new jaw was implanted under the skin below the man’s right shoulder blade, within the latissimus dorsi muscle. It was allowed to remain and grow there for seven weeks before being removed along with a flap of muscle containing blood vessels.
After extracting the graft from the titanium mesh, surgeons succesfully transplanted it to the man’s face, where it was attached with screws on to the stumps left of the original lower jaw. The muscle flap was also transplanted on to the site.
Advertisement
Doctors who carried out the pioneering procedure at a hospital in Germany said that it opened up new avenues for the modelling of damaged bones and grafts. Conventional bone grafts, which are usually taken from another part of the body, such as the hip, often risk leaving serious damage behind, which can cause major secondary health problems.
In this patient’s case, a large chunk of bone, muscle and veins would have had to be taken from his lower leg.
The German man had had surgery for a bone tumour in his jaw eight years before the operation, when a large section of the bone had been removed. He had also suffered cell damage from radiation treatment given at the time. Since the surgery to remove the piece of jawbone, the patient had been able to eat only soft foods and soup.
Patrick Warnke, of the department of oral and maxillofacial surgery at the University of Kiel, described how the man, 56, regained the ability to chew soon after having the transplant. A month later he enjoyed his first solid dinner in almost a decade: a plate of bread and sausages.
Dr Warnke said that the approach to bone construction, with the help of computer tomography, had significantly reduced the need for numerous facial operations because the replacement bone had been much more accurately shaped.
Advertisement
“By the fourth week post-transplantation the patient enjoyed his first dinner in nine years; before reconstruction he had been able to eat only soft food and soup,” he said. “Even with his edentulous (toothless) jaws, he was now able to undertake a small amount of mastication. The patient was also satisfied with the aesthetic outcome of the procedure.”
The promising results of the operation — including aesthetic approval from the patient — had prompted a further extension of clinical trials of such bone fabrication, Dr Warnke said. But he added that many vital questions still remained unanswered.
“For us to draw firm conclusions, an extended period of follow-up is necessary,” he said. “We hope to present this patient’s long-term outcome and those of future patients at a later date.”
Writing in The Lancet, Stan Gronthos, a haematologist from the Hanson Institute in Adelaide, Australia, said that the operation marked an important development in tissue engineering which bypassed the need to use bone segments derived from the patient’s own body. He said that trials of the different elements of bioengineering — organic materials, growth factors and stem cells — would bring further rewards.