According tomedia reports, we have heard of implants with a microstructure similar to scaffolding to help heal broken bones by providing a migration place for bone cells. However, a new material may work better and provide electrical stimulation. Scientists have previously successfully used implants to simulate the body’s own electric field, stimulating bone cells to reproduce. Unfortunately, these devices are often bulky and require an integrated (and potentially toxic) battery or hard-wired external power supply. In addition, once the broken bone has healed, the implant must be surgically removed.
Led by biomedical engineer Thanh Nguyen, scientists at the University of Connecticut have developed a stent material that can provide electrical stimulation that never needs to be removed. It is made from nanofibers of a non-toxic piezoelectric polymer called polyL-lactic acid or PLLA- a piezoelectric material that generates an electrical charge when it exerts mechanical stress.
The idea is that after the material is implanted at the fracture site, doctors and even patients regularly use external handheld devices to send them ultrasonic pulses. These pulses cause the scaffoldtotototoe to vibrate, and the stress produced by these vibrations creates a weak but therapeutic electric field. As the body’s stimulated bone cells continue to reproduce in the stent, they dissolve harmlessly. Eventually, the material will be completely replaced by natural bones, so nothing is needed to be removed.
In the current tests, the material has been used to promote the healing of skull fractures in mice. Scientists are now working to make the stents more beneficial to bone growth and to better understand how electric fields stimulate bone cell reproduction. Eventually, it is hoped that the technology will also help other types of tissues, such as muscles, nerves or cartilage, regrow.
The paper on the study was recently published in the journal Nanoenergy.