Researchers at the Université de Montréal with help from McGill University, the Institut National de la Recherche Scientifique (INRS-EMT), Plasmionique Inc and the Universidade de São Paulo, have managed to chemically modify titanium to create so called “intelligent surfaces”. The new material can interact with cells in the body and either promote healing or suppress their growth. It is believed that this research will lead to smart prostheses that will help promote healing of tissue post implantation.
Dr. Nanci [Antonio Nanci, the study’s senior author and a professor at the Université de Montréal’s Faculty of Dentistry] and colleagues applied chemical compounds to modify the surface of the common biomedical metals such as titanium. Exposing these metals to selected etching mixtures of acids and oxidants results in surfaces with a sponge-like pattern of nano (ultra small) pits. “We demonstrated that some cells stick better to these surfaces than they do to the traditional smooth ones,” says Dr. Nanci. “This is already an improvement to the standard available biomaterial.”
The researchers then tested the effects of the chemically-produced nanoporous titanium surfaces on cell growth and development. They showed that the treated surfaces increased growth of bone cells, decreased growth of unwanted cells and stimulated stem cells, relative to untreated smooth ones. In addition, expression of genes required for cell adhesion and growth were increased in contact with the nanoporous surfaces.
Uncontrolled growth of cells on an implant is not ideal. For example, when using cardiovascular stents, it is important to limit the growth of certain cells in order not interfere with blood flow. Also, in some cases, cells can form an undesirable capsule around dental implants causing them to fall. The scientists demonstrated that treatment with specific etchants reduced the growth of unwanted cells.