Fabrication of an ordered micro-/nanotextured titanium surface to improve osseointegration.

Ordered microscale titanium (Ti) surface topography with homogeneous cell-sized microholes (20 µm in diameter) was fabricated using simple electrochemical etching. The as-prepared surface imposed with uniform titania nanotubes (TNTs, 70 nm in diameter) through electrochemical anodization showed no considerable change in the initial microscale morphology. Bone marrow mesenchymal stem cells (BMSCs) were used in evaluating the bioactivity. Compared with polished Ti and unordered microtextured Ti, the ordered microtextured Ti formed by electrochemical etching remarkably promoted cell attachment, alkaline phosphatase activity, collagen secretion, extracellular matrix mineralization, and osteogenesis-related gene expression but considerably inhibited cell proliferation. After TNTs were introduced to the ordered microtextured Ti, cell attachment and osteogenic differentiation indexes were further enhanced, and cell proliferation recovered over time. The ordered micro-/nanotextured Ti surface was more conducive to the cell attachment, proliferation, and osteogenesis of BMSCs than polished Ti with and without TNTs, unordered microtextured Ti with and without TNTs, and unitary ordered microtextured Ti. Thus, the novel ordered bio-inspired micro-/nanotextured structure composed of cell-sized microholes and TNTs on the Ti surface possessed a favorable interfacial environment that improved osseointegration, potentially optimizing Ti implant surface topography.