Biomedical Engineering Reference
In-Depth Information
Mendonça and coworkers recently reviewed the role of
nanoscale topographic modiication of titanium substrates for the
purpose of improving osseointegration [89]. Depiction of broad
range of nanoscale topography effects observed in cellular protein
adsorption is altered by nanoscale modiication of bulk material
(Fig. 12.1). It is believed that, the changes in initial protein-surface
interaction control osteoblast adhesion [14]. When implants come
into contact with a biological environment, protein adsorption
(e.g. plasma ibronectin) that occurs immediately will mediate
subsequent cell attachment and proliferation. Changing the surface
energy or wettability of a biomaterial represents a classical approach
to altering cell interactions with the surface.
Webster and coworkers [136, 138, 142, 153] observed increased
osteoblast adhesion on Ti, Ti6Al4V, and CoCrMo compacts with
nanometer compared to conventionally sized particles. Respective
metal formulations had similar chemistry and altered only in degree
of nanometer roughness. Interestingly, osteoblasts were observed to
adhere speciically at particle boundaries. Since nanophase metals
have higher percentages of particle boundaries at the surface, this
may explain the greater numbers of osteoblasts on nanophase
compared to conventional metals.
Figure 12.1
Depiction of broad range of nanoscale topography effects
observed in cellular protein adsorption is altered by
nanoscale modiication of bulk material [89].
Previous studies have also demonstrated increased functions
of osteoblasts (bone-forming cells) on nanophase compared to
conventional ceramics (speciically, alumina, titania, and hydro-
