Living cells can perceive and respond to the geometry of their environment. "Cells sense and respond to the geometry of the surfaces they are exposed to. Depending on their curvature, surfaces can either encourage cells to create new tissue or prevent them from doing so," says Amir Zadpoor, professor of Biomaterials and Tissue Biomechanics, supervisor of a study showing that the curvature of biomaterials inhibits or stimulates bone cells to make new tissue. "Stimulating curvatures made by a 3D printer are an easy and safe way to promote tissue growth. As compared to drugs, they are also much cheaper."