Cellular Responses to Nanoscale Surface Modifications of Titanium Implants for Dentistry and Bone Tissue Engineering Applications - Emerging Nanotechnologies in Dentistry - page 119

Table 8.3 (Continued)
Modified
Structures/
Chemicals

Modification
Methods

Materials
Used

Cell Type Cell Responses References

Surface
chemistry with
HA and titania

Sol-gel process HA, TiO 2 Human

osteoblast-
like cells

Improved corrosion
resistance

[39,103]

Increased ALP activity
Enhanced cell adhesion [103]

Increased number of
mineralized nodules

MC3T3-E1

Surface
chemistry
with titania
composites

Nanophase
titania, sonication
disperse

PLGA,
titania

Human
osteoblasts

Increased cell adhesion [104]

Enhanced bone
functions (e.g., collagen,
ALP activity, calcium,
and mineral deposition)

Surface
chemistry with
aluminum oxide
(Al 2 O 3 )

Dipping Al 2 O 3 RMSC Promoted stem cells

to the osteoblast
phenotype

[105]

Surface
chemistry with
nanoscale
materials

Sol-gel-derived
coating

Anatase
(An), rutile
(Ru),
alumina (Al),
and zirconia
(Zr)

hMSC Improved cell adhesion [106]

Upregulated osteoblast
differentiation genes,
BSP, and OSX

Surface
chemistry with
bioactive glass

Blasted Ti with
granules

Bioactive
glass
particles

MC3T3-E1 Induced ALP activity [107]

Enhanced osteogenic
potential

hMSC, human mesenchymal stem cells; hSaSO-2, human osteoblast cell line; BAEC, bovine aortic endothelial cells; hFOB,
human fetal osteoblast progenitor cell line; MC3T3-E1, mouse osteoblast cell line; MG63, human osteosarcoma immortalized
cell line; RMSC, rat bone marrow stromal cells.

implants as shown in Figure 8.2 . In the case of nanotubes that have self-assembled into an array,
cellular response is determined by the nanotube dimension and the spacing between the nanotubes
in the array. These factors can have a major effect on the osteoblast behavior. The spaces between
nanotubes provide a physical pathway for the nutrients to reach the cells after the nanotubes have
adhered to the surface, whereas nanostructures on the implant surfaces would improve the cellular
adhesion [75] . Surface roughness of the nanotopography is also a major factor in the determination
of the proliferative activity. Root-mean-square roughness values of 0.5-13 nm significantly decrease
the proliferation of osteoblasts. Rougher surfaces lower proliferation while smoother surfaces pro-
mote proliferation [128] . A nanometric net of titanium filaments, on the other hand, can increase
osteoblast proliferation [129] .