[Construction of nano-granule titanium film and study of its surface topography].

OBJECTIVE: To construct four different micro- and nano-phase titanium film models and investigate the characteristics of their surface micro-topography. METHODS: Four different titanium films were prepared on commercial titanium discs, by direct current magnetron sputtering, at ambient, 100, 250, 380 degrees C substrate temperature, respectively. Their surface topography and crystal sizes were investigated using atomic force microscope (AFM) and X-ray diffraction (XRD). The size of granule and surface roughness in different group was calculated and compared. RESULTS: All samples were covered by a thin film consisting of dense round or ovaloid granules. The granules and crystals was growing as the substrate temperature increasing. The Ti substrate had greater effect on the surface topography of film compared with Si substrate. This kind of complex topography caused the surface roughness of Ti substrate group decreased as the granules growing. CONCLUSION: In our study, four different micro- and nano-phase titanium film models were constructed for our coming investigation of their topographical influence on biological reaction of proteins and cells. Basic data on surface features was obtained for next in vitro and in vivo experiment.

[Effect of nano-granule titanium films on synthesis of osteoblasts].

OBJECTIVE: To compare the synthetic ability of osteoblasts on the surface of different nano-granule titanium films and investigate the correlation between nanophase titanium films and cellular biocompatibility. METHODS: Four different nano-granule titanium films were produced by direct current magnetron sputtering, at ambient, 100 degrees C, 250 degrees C, 380 degrees C substrate temperature, respectively. Rat osteoblasts were seeded on the surface of four treated groups of titanium film samples and non-treated Ti sample(control group). The production of osteocalcin (OC) in all five groups were detected by using double antibody sandwich enzyme-linked immunosorbent assay. RESULTS: The production of OC increased gradually from day 7 to day 14 in all groups. In the control group, it showed significant differences with other five groups on day 7. On day 14, the production of OC in 100 degrees C group was the highest, and it showed significant differences with 380 degrees C, control group and blank group. In 250 degrees C group, the production of OC also showed significant differences with 380 degrees C, control group and blank group (P < 0.05). CONCLUSION: Titanium with nano-modified surface had good biocompatibility and different nano-granule titanium films could affect the synthesis of osteoblasts.