Mesh cage in shoulder blade used to grow new jaw bone

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http://seattletimes.nwsource.com/html/nationworld/2002017103_jaw27.html

A German whose lower jaw was cut out because of cancer has enjoyed his first

meal in nine years ‹ a bratwurst sandwich ‹ after surgeons grew a new jaw

bone in his back muscle and transplanted it to his mouth in what experts

call an " ambitious " experiment.

According to this week's issue of The Lancet medical journal, the German

doctors used a mesh cage, a growth chemical and the patient's bone marrow,

containing stem cells, to create a new jaw bone that fit exactly into the

gap left by the cancer surgery.

Tests have not been done to verify whether the bone was created by the

blank-slate stem cells, and it is too early to determine whether the jaw

will function normally in the long term. But the operation is the first

published report of a whole bone being engineered and incubated inside a

patient's body and transplanted.

Stem cells are the master cells of the body that go on to become every

tissue in the body. They are a hot area of research with scientists trying

to find ways to prompt them to make desired tissues, and perhaps organs.

The operation was done by Dr. Warnke, a reconstructive facial

surgeon at the University of Kiel in Germany. The patient, a 56-year-old

man, had his lower jaw and half his tongue cut out almost a decade ago after

developing mouth cancer. He since had been able only to slurp soft food or

soup from a spoon.

In similar cases, doctors sometimes can replace a lost jawbone by cutting

out a piece of bone from the lower leg or from the hip and chiseling it to

fit into the mouth.

This patient could not have that procedure because he was taking a potent

blood thinner for another condition and doctors considered it too dangerous

to harvest bone from elsewhere in his body since extraction leaves a hole

where the bone is taken, creating an extra risk of bleeding....

Several cow-derived pure bone mineral blocks the size of sugar lumps then

were put inside the structure, along with a human-growth factor that builds

bone and a large squirt of blood extracted from the man's bone marrow, which

contains stem cells.

The surgeons then implanted the mesh cage and its contents into the muscle

below the patient's right shoulder blade. He was given no drugs, other than

routine antibiotics.

The implant was left in for seven weeks, when scans showed new bone

formation. Scans showed new bone continued to form after the transplant...

Just making the gross tissue shape right isn't really the problem, " Brown

said. " It's what the shape of the tissue is at the microscopic and

ultramicroscopic level. That's the architecture which is so tricky and which

is what gives function. "