A magnification of cells grow on a metal surface appear on the left screen. On the right screen is a higher-resolution view of the metal's surface.

Antonio Nanci likes to dream about the day when a hip replacement could signal to a patient’s doctor that it needs to be repaired and car paint could be never be chipped because of the pigment molecularly fused into the metal.

The work of the researcher in the Faculty of Dentistry goes far beyond the teeth that lie jarred in a glass display case outside his office

Dr. Nanci’s dreams are an outgrowth of the innovative work he has already accomplished in the field of cellular biology of calcified tissues. Before he time-travels into the future, there are some problems challenging him in our current world.

He has been working to improve the technology behind hip replacements and dental implants.

While the know-how that inserts metal into bone has helped countless people, the technology is still not that compatible with our biology. The body hates having a foreign object in it and usually reacts adversely. That’s why scientists began making these replacements and implants out of titanium. Titanium is inert and rarely causes a reaction, and while most metals would leach toxic particles into our body, titanium rarely breaks down.

But there is still a problem that plagues patients and manufacturers. The bond formed when bone meets bone can not be truly mimicked when bone meets metal. It often takes a long time –and sometimes it never happens –for a seal of bone to form around the metal, and the structure to become stable. This is compounded in an older person who can not generate replacement bone as efficiently. In those circumstances, the bone can further deteriorate or the implant or replacement can become dislodged.

Illustration of an implant

Enter Dr. Nanci, who has become a matchmaker between titanium and bone and was recently recognized with a prestigious federal Collaborative Health Research Projects grant (CHRP) (Projets de recherche concertée sur la santé (PRCS)). Not only has the researcher worked on changing the surface of the titanium, forming a mini topography of peaks and valleys for the bone and metal to better latch onto each other. His team has also been working on ways to permanently attach specific molecules to metal surfaces, taking this latching further and acting as a pied piper for repair cells to march over to where they are most needed.

The first principal is that when bones need to repair themselves, they call on specific cells that activate the repair process. Another is that when we break a bone, it needs to be set so vascular cells have a chance to start building blood vessels that support bone formations. With his electron microscopes, Dr. Nanci has been getting a closer look at these peaks and valleys of the titanium and has been experimenting with ways to coax signals to the cells that help in bone repair.

“My question is, can we create intelligent surfaces that send signals to healing cells,” says Nanci, who has been at the university for 21 years.

His interdisciplinary team, which includes UdeM organic chemist James D. Wuest and INRS-EMT’s Federico Rosei, a surface physicist, have been working at a nano level, to physically attract bone repair cells.

“It’s like going fishing and setting out bait for the cells,” explains Dr. Nanci, whose work on cellular manipulations uses physical approaches and thus avoids introducing any chemicals to the body.

Nanci, who is currently in talks with a major American orthopaedic manufacturer, is using some basic principals that have affected anyone who has broken a bone, to do some extremely complex work in nanobiology.

Back to the future, Nanci believes this work coaxing cells could be applied beyond dental implants and hip replacements and could mean improvements in vascular stents and targeted drug delivery. Intelligent surfaces could even send important messages to adult stem cells, which offer hope in a wide variety of medical applications.

Asked whether there could be industrial applications to this work, Dr. Nanci questioned if nano pores in metal could, for instance be used to better adhere paint to a metal surface. If that ever came to be, it could eventually help anyone that has ever gotten their car ‘keyed’ or has had paint come off in a fender-bender. By pouring the pigment into the nano-pores of the metal, the paint would never be scratched off from something as big as another fender or a key. Dr. Nanci says you’d actually need a nano-key to do that kind of damage. Who knows, he may be in talks one day with an enterprising vandal.

Philip Fine