Evaluation of Osteoblast-Like Cell Viability and Differentiation on the Gly-Arg-Gly-Asp-Ser Peptide Immobilized Titanium Dioxide Nanotube via Chemical Grafting.

This study examined the effect of the immobilization of the Gly-Arg-Gly-Asp-Ser (GRGDS) peptide on titanium dioxide (TiO2) nanotube via chemical grafting on osteoblast-like cell (MG-63) viability and differentiation. The specimens were divided into two groups; TiO2 nanotubes and GRGDS-immobilized TiO2 nanotubes. The surface characteristics of GRGDS-immobilized TiO2 nanotubes were observed by using X-ray photoelectron spectroscopy (XPS) and a field emission scanning electron microscope (FE-SEM). The morphology of cells on specimens was observed by FE-SEM after 2 hr and 24 hr. The level of cell viability was investigated via a tetrazolium (XTT) assay after 2 and 4 days. Alkaline phosphatase (ALP) activity was evaluated to measure the cell differentiation after 4 and 7 days. The presence of nitrogen up-regulation or C==O carbons con- firmed that TiO2 nanotubes were immobilized with GRGDS peptides. Cell adhesion was enhanced on the GRGDS-immobilized TiO2 nanotubes compared to TiO2 nanotubes. Furthermore, significantly increased cell spreading and proliferation were observed with the cells grown on GRGDS-immobilized TiO2 nanotubes (P < .05). However, there was no significant difference in ALP activity between GRGDS-immobilized TiO2 nanotubes and TiO2 nanotubes. These results suggest that the GRGDS-immobilized TiO2 nanotubes might be effective in improving the osseointegration of dental implants.

Preparation and Characterisation of Hydroxyapatite Coatings on Nanotubular TiO2 Surface Obtained by Sol-Gel Process.

Hydroxyapatite (HA) coating on titanium dioxide (TiO2) nanotubular surface has been developed to complement the defects of both TiO2 and HA. A sol-gel processing technique was used to coat HA on TiO2 nanotubular surface. All the titanium discs were blasted with resorbable blast media (RBM). RBM-blasted Ti surface, anodized Ti surface, and sol-gel HA coating on the anodized Ti surface were prepared. The characteristics of samples were observed using scanning electron microscopy and X-ray photoemission spectroscopy. Biologic responses were evaluated with human osteosarcoma MG63 cells in vitro. The top of the TiO2 nanotubes was not completely covered by HA particles when the coating time was less than 60 sec. It was demonstrated the sol-gel derived HA film was well-crystallized and this enhanced biologic responses in early stage cell response.

Hydroxyapatite coatings on nanotubular titanium dioxide thin films prepared by radio frequency magnetron sputtering.

In this study, hydroxyapatite (HA) was coated on anodized titanium (Ti) surfaces through radio frequency magnetron sputtering in order to improve biological response of the titanium surface. All the samples were blasted with resorbable blasting media (RBM). RBM-blasted Ti surface, anodized Ti surface, as-sputtered HA coating on the anodized Ti surface, and heat-treated HA coating on the anodized Ti surface were prepared. The samples were characterized using scanning electron microscopy and X-ray photoemission spectroscopy, and biologic responses were evaluated. The top of the TiO2 nanotubes was not closed by HA particles when the coating time is less than 15 minutes. It was demonstrated that the heat-treated HA was well-crystallized and this enhanced the cell attachment of the anodized Ti surface.