Researchers working at a multidisciplinary lab at the University of Sheffield have succeeded in helping a damaged nerve repair itself using a 3D-printed guide.
The nerve guidance conduits (NGCs) have been successfully used in animals, and the research team believes they can now be used to treat traumatic injuries -- such as those caused by chainsaw or car accidents -- in humans.
Nerves have very little natural ability to regenerate themselves after they have been injured, which is why surgical intervention is required to help relieve the debilitating loss of the sensation that people can experience after injury. The conduits consist of a framework of tiny tubes that guide damaged nerve endings towards one another in order to promote natural regeneration. They are created through a complex form of 3D printing that sees laser light building up tiny blocks of materials into a 3D solid structure.
The hope is that the conduits could be used to replace current methods of repairing peripheral nerve damage, which involve surgery to graft together the nerve endings. Not only does this often yield imperfect results that do not return sensation to damaged area, but it can also require two surgery sites.
This laser technique, on the other hand, is so precise that it allows the NGCs to be adapted for any nerve damage or for a specific patient. In the researchers' tests on mice, they were able to demonstrate successful regrowth over a 21-day period to a 3mm nerve gap.
"The advantage of 3D printing is that NGCs can be made to the precise shapes required by clinicians," says John Haycock, professor of Bioengineering at Sheffield. "We've shown that this works in animal models, so the next step is to take this technique towards the clinic."
The next step will be testing the NGCs to see if they work over -- or can be adapted to work over -- larger gaps, as well as ensuring that they comply with regulatory requirements. Fortunately the team has been working with a material called polyethylene glycol, which has already been cleared for clinical use.
A paper detailing the work of the Sheffield research team on developing and effectively using the NGCs has been published in the journal Biomaterials.