Effect of a Hybrid Micro/Nano-integrated Titanium Surface on Behavior of Rat Osteoblasts

The objective of this study was to investigate the effect of a new combined micro/nanoscale implant surface feature on osteoblasts＇ behaviors including cell morphology, adhesion, proliferation, differentiation, and mineralization in vitro. A new micro/nano-hybrid topography surface was fabricated on commercial pure titanium（Cp Ti） by a two-step sandblasted acid-etching and subsequent alkali-and heattreatment（SA-AH）. The conventional sandblasted/acid-etching（SA） treatment and alkali and heat（AH） treatment were also carried out on the Cp Ti as controls. Surface microstructures of the Ti disc samples were assessed by scanning electron microscopy（SEM）. The neonatal rat calvaria-derived osteoblasts were seeded on these discs and the initial cell morphology was evaluated by SEM and immunofluorescence. Initial adhesion of the cells was then assayed by DAPI staining at 1, 2, and 4 h after seeding. The Cell Counting Kit-8（CCact K8） assay, gene expression of osteoblastic markers（ALP, Col 1, OCN, BSP, OSX, Cbfα1） and Alizarin Red S staining assays were monitored respectively for cell proliferations, differentiation and mineralization. The results show significant differences in osteoblast＇s behaviors on the four kinds of Ti surfaces. Compared with Cp Ti surface, the SA and AH treatment can significantly promote cell adhesion, differentiation and mineralization of osteoblasts. In particular, the combined SA and AH treatments exhibit synergistic effects in comparison with the treatment of SA and AH individually, and are more favorable for stimulating a series of osteogenous responses from cell adhesion to mineralization of osteoblasts. In summary, this study provides some new evidence that the integrated micro/nanostructure on the Cp Ti surface may promote bone osseointegration between the Ti implantbone interfaces in vitro.

A potential flower-like coating consisting of calcium-phosphate nanosheets on titanium surface

Titanium and its alloys have been widely used as implant materials in bio-medicine.Additionally,surface modification has been utilized to improve the chemical and morphological properties of materials.More specifically,biocoating,especially the calcium-phosphate nano-coating,has been widely used in the research field.In this study,a novel calcium-phosphate nanoflower coating was performed on the titanium surface by a simple approach.This study indicated that the novel calcium-phosphate flower-like coating consisting of calcium-phosphate nanosheets had high surface area,low cytotoxicity as well as promising cell affinity.Hence it could be a potential alternative modification method for titanium.

Effect of Electric Field Imposition on Metal Anodizing Behavior

Anodic oxidation processes for metal surface have been utilized many materials,for example,porous alumina, nano-silicon crystal,and so on.In these materials,anodizing surface treatment for titanium or zirconium is useful for biocompatible material,like artificial bones and joints.In anodizing behavior,successive dielectric breakdown makes the surface microscopic bumpy morphology,which is important for the biocompatibility.Electric field can promote the oxidation behavior at the anodizing surface.As the result of the anodizing experiments using titanium or zirconium plate(10mm × 10mm),it is found that the anodized film becomes thicker and the microscopic honeycomb structure becomes finer and uniform by the imposition of electric field up to 200 kV/m.