Implant Coating to Revolutionise Prosthetics
As is well known, the greatest difficulty with prosthetic implants that invade the body, is the material that comes into contact with the flesh of an organic form. If it is too smooth, flesh does not bond with it well, and it slips. Too rugged and it becomes a nesting ground for bacteria. That's not even touching on the immune reaction if the material is the wrong type and is seen as a threat.
The ideal prosthetic should resemble biological material as closely as possible. Further to that, it should resemble the person's own DNA as much as possible. Of course, one common need for a prosthetic is when the original DNA is a bit buggered and created a deformity. Cloned material is definitely out there - assuming we even had such a source, which at this time we do not.
Of course, organics would also mean replacing like for like, and that is a problem if we desire to implant a prosthetic that was never naturally there. Cancer filtration implants are an example of such that are just leaving the lab for the first time as this is being penned. A wholly foreign organ that is implanted into the body along a major artery, and filters out any loose cancerous cells in the blood, preventing them from spreading inside the body. Its not natural to have something like that, so how do you stop the body attacking it?
Well, Tel Aviv University researcher Prof. Noam Eliaz of the TAU School of Mechanical Engineering has come up with an interesting way to do that. As was pointed out above, its not the material the implant is made from, that is the problem. It's the material that touches the flesh of the body. His ingenious idea was a coating that covers the implant, giving it an organic feeling as far as the body is concerned.
The coating is electrochemical in nature, meaning it is ideal to use to plate titanium or aluminium implants, keeping their strong but light properties unscathed. The implant survives intact in the body for a great deal longer, functions in a superior manner as it binds tight into the tissue, and thus integrates completely, with the body. It also reduces wear and tear on the implant by 33% according to initial studies, as none of the metal is exposed to bodily fluids.
"The surface chemistry, structure and morphology of our new coatings resemble biological material," explains Prof. Eliaz. "We've been able to enhance the integration of the coating with the mineralised tissue of the body, allowing more peoples' bodies to accept implants."
Prof. Eliaz presented his findings to the 215th meeting of the Electrochemical Society in San Francisco in May 2009. In addition, a new 12-week implantation study, recently published in the journal Acta Biomaterialia, favorably compared the performance of the Tel Aviv University coatings to those of current commercial coatings.