Interfaces and interphases of (bio)materials: Definitions, structures, and dynamics

What exactly is an interface, and when is an interphase the more correct concept? The nature of interfaces and the phenomena occurring there are described before the role of interphases is illustrated with a series of examples taken from purely artificial systems (e.g., polymer and polymer‐metal “interfaces”) and natural and mixed artificial–natural systems (e.g., the multilayer interphase of a biomedical system such as a dental implant). The approach presented demonstrates that “interphase” or “interface” depends to some extent on the point of view.