Future prospects for nanotechnology and biomaterials in medical applications appear to be excellent. In orthopedic applications, there is a significant need and demand for the development of a bone substitute that is bioactive and exhibits material properties (mechanical and surface) comparable with those of natural, healthy bone. Particularly, in bone tissue engineering, nanometer-sized ceramics, polymers, metals and composites have been receiving much attention recently. This is a result of current conventional materials (or those materials with constituent dimensions >1 µm) that have not invoked suitable cellular responses to promote adequate osteointegration to enable these devices to be successful for long periods. By contrast, owing to their ability to mimic the dimensions of constituent components of natural bone (e.g., proteins and hydroxyapatite), nanophase materials may be an exciting successful alternative orthopedic implant material. In this article, the ability of novel nanomaterials that promote osteointegration is discussed. Potential pitfalls or undesirable side effects associated with the use of nanomaterials in orthopedic applications are also reviewed.