In
the field of biomedical technology, a critical aspect is the
ability to control and understand the integration of an implantable
device in living tissue. Despite the technical advances in the development
of biomaterials, the elaborate interplay encompassing materials science
and biology on the atomic level is not very well understood. Within
implantology, anchoring a biomaterial device into bone tissue is termed
osseointegration. In the most accepted theory, osseointegration is
defined as an interfacial bonding between implant and bone; however,
there is lack of experimental evidence to confirm this. Here we show
that atom probe tomography can be used to study the implant–tissue
interaction, allowing for three-dimensional atomic mapping of the
interface region. Interestingly, our analyses demonstrated that direct
contact between Ca atoms and the implanted titanium oxide surface
is formed without the presence of a protein interlayer, which means
that a pure inorganic interface is created, hence giving experimental
support to the current theory of osseointegration. We foresee that
this result will be of importance in the development of future biomaterials
as well as in the design of in vitro evaluation techniques