RESUMEN
Titanium has been used for biomedical devices due to its excellent biocompatibility, which is based partly on its 2-8 nm thick titanium oxide layer. However, the relatively poor surface hardness, wear resistance and metal release of these layers may cause some problems in clinical application. In this study, titanium surfaces were modified using a TiO2 sol-gel coating, in order to improve surface properties and osteoblast function. No significant difference in surface roughness was observed between titanium and TiO2 sol-gel discs. The surface of TiO2 sol-gel discs possessed more wettability than titanium discs. The X-ray diffraction results showed amorphous TiO2 phase on titanium discs, whereas TiO2 sol-gel surfaces presented TiO2 rutile and anatase phase. After 4 hours, the number of osteoblasts seeded on TiO2 surface was significantly higher than those on titanium discs. The mRNA expression of bone sialoprotein and osteocalcin were also higher on day 5 and 7, respectively. Enzyme-linked immunosorbent assay(ELISA) analysis confirmed the increase of osteocalcin protein synthesis in osteoblasts grown on the TiO2 sol-gel surface. Alizarin red-S staining showed higher amount of calcium deposition from osteoblasts cultured on TiO2 surface than those on titanium discs at day 20. In conclusion, TiO2 sol-gel coated-titanium could enhance osteoblasts differentiation and promote mineralization, indicating its potential in improving osseointegration for clinical application.