Biomedical Engineering Reference
In-Depth Information
A comparison of cell densities on the different anodized
surfaces for 5, 11, and 16 days was shown, as well (Fig. 9.35) [14].
For all days of culture, surfaces etched in H
3
PO
4
electrolytes show
the highest cell density. Cell density for the anodic oxide increases
in the order of H
3
PO
4
< HF < H
2
SO
4
< Ti-control. The HF and H
3
PO
4
oxidized surfaces are rougher than H
2
SO
4
and polished Ti-control
surfaces. Therefore, the surface morphology and properties, such
as high roughness, low values of contact angles, high wettability,
and high surface energy plays a crucial role in cell attachment. The
rough H
3
PO
4
surface with improved wettability enhances the cell
attachment process [14].
Figure 9.35
Optical density measured after culture for 5, 11, and 16 days
[14].
9.2.2 TiO
2
Nanotubes and Nanofibers
Nanotubes or nanoibers have shown good biological behavior, for
example, improved cell adhesion and differentiation, and therefore
exhibit potential in osseointegration for dental and bone implants
applications.
Anodization of titanium can result in pores [28] or nanotubes
formation [66, 122]. Beside anodization [19, 51], the titanium
oxide nanotubes can be prepared by various techniques such as
sol-gel method [46], electrophoretic deposition [56], hydrothermal
method [87], seed growth [86], and template-assistant deposition
[77]. Uniform TiO
2
nanotube arrays dimensions can be carefully
controlled by adjusting electrolyte composition, pH, and voltage
