Biomedical Engineering Reference
In-Depth Information
F
−
ions show very good initial attachment of cells (group I), and
PO
4
3−
ions show a good cells growth for 7 days (group II) and these
results are attributed to a low surface potential for favoring the cell
attachment caused by F
−
ions and osteoblast growth by phosphate
ions, respectively [44].
Figure 9.17
Morphology maps of anodic titanium oxides prepared
at different anodization conditions; (a-f) are the results
of samples denoted in Fig. 9.16. Group I shows a good
attachment of cells at an initial stage and group II exhibits
the good proliferation of cells for the period of 7 days [44].
Yang
et al
. [112] investigated electrochemical anodization of
Ti to produce a nano/submicron-scale network oxide layer for
biomedical implant application. Biological species (blood and cells)
have various dimensions ranging from nm to μm. Yang
et al
. suggests
that a mixed nano- and submicron Ti implant surface may have
better initial responses to blood and cells [112]. SEM images of the Ti
specimens with and without anodization obtained by Yang
et al
. are
shown on Fig. 9.18. A multilayered nano/submicron-scale network
is clearly visible. The lateral pore size for I
1
and I
2
specimens (both
below 0.2 A, but I
1
< I
2
) were approximately 20-110 and 30-160 nm,
respectively. The thickness of the multilayered network was about
180 nm for I
1
and 320 nm for I
2
. Increase of anodic current led to an
increase in network pore size and thickness. This surface network
layer structure is build mainly from anatase TiO
2
-type structure.