PROVIDENCE, R.I. [Brown University] In recent years, researchers have worked to develop more flexible, functional prosthetics for soldiers returning home from battlefields in Afghanistan or Iraq with missing arms or legs. But even new prosthetics have trouble keeping bacteria from entering the body through the space where the device has been implanted.
"You need to close (the area) where the bacteria would enter the body, and that's where the skin is," said Thomas Webster, associate professor of engineering and orthopaedics at Brown University.
Webster and a team of researchers at Brown may have come across the right formula to deter bacterial migrants. The group reports two ways in which it modified the surface of titanium leg implants to promote skin cell growth, thereby creating a natural skin layer and sealing the gap where the device has been implanted into the body. The researchers also created a molecular chain to sprinkle skin-growing proteins on the implant to hasten skin growth.
The findings are published in the Journal of Biomedical Materials Research A.
The researchers, including Melanie Zile, a Boston University student who worked in Webster's lab as part of Brown's Undergraduate Teaching and Research Awards program, and Sabrina Puckett, who earned her engineering doctorate last May, created two different surfaces at the nanoscale, dimensions less than a billionth of a meter.
In the first approach, the scientists fired an electron beam of titanium coating at the abutment (the piece of the implant that is inserted into the bone), creating a landscape of 20-nanometer mounds. Those mounds imitate the contours of natural skin and trick skin cells into colonizing the surface and growing additional keratinocytes, or skin cells.
Webster knew such a surface, roughened at the nanoscale, worked for regrowing bone cells and cartilage cells, but he was unsure whether it would be successful a
|Contact: Richard Lewis|