A homogeneous and uniform array of nanotubes with a diameter of about 70 nm was produced on titanium (Ti) surface by anodic oxidation. The wall thickness of the nanotubes was around 20 nm, and the depth was about 200 nm. The biological properties of the anodized Ti surface were investigated by simulated body fluid (SBF) soaking test and in vitro cell culture test. The mechanical properties were evaluated by instrumented nanoindentation test and friction-wear test. The results showed that the anodized Ti surface can induce the formation of bone-like apatite after immersion in SBF for four weeks, enhance cell adhesion, proliferation and gene expression, it also showed decreased friction coefficient, similar stiffness and Young’s modulus to those of the cortical bone. Based on these results, it can be concluded that anodic oxidation endowed the Ti surface with improved biological and mechanical properties, which was attributed to the formation of nanostructured surface.
KrishnaB.BoseS. and BandyopadhyayA., Low stiffness porous Ti structures for load-bearing implants, Acta Biomateri.3 (2007), 997–1006. doi:10.1016/j.actbio.2007.03.008.
2.
LiuL.SongL.YangG.ZhaoS. and FabricationH.F., Characterization, and biological assessment of multilayer DNA coatings on sandblasted-dual acid etched titanium surface, J. Biomed. Mater. Res. A97 (2011), 300–310. doi:10.1002/jbm.a.33059.
3.
GuY.DuJ.SiM.MoJ.QiaoS. and LaiH., The roles of PI3K/Akt signaling pathway in regulating MC3T3-E1 preosteoblast proliferation and differentiation on SLA and SLActive titanium surfaces, J. Biomed. Mater. Res. A101 (2013), 748–754. doi:10.1002/jbm.a.34377.
4.
LiB.LiuX.CaoC.MengF.DongY.CuiT. and DingC., Preparation and antibacterial effect of plasma sprayed wollastonite coatings loading silver, Appl. Surf. Sci.255 (2008), 452–454. doi:10.1016/j.apsusc.2008.06.143.
5.
BalasundaramG.YaoC. and WebsterT., TiO2 nanotubes functionalized with regions of bone morphogenetic protein-2 increases osteoblast adhesion, J. Biomed. Mater. Res. A84 (2008), 447–453. doi:10.1002/jbm.a.31388.
6.
ShibataY.TanimotoY.MaruyamaN. and NagakuraM., A review of improved fixation methods for dental implants. Part II: Biomechanical integrity at bone-implant interface, J. Prosthodont. Res.59 (2015), 84–95. doi:10.1016/j.jpor.2015.01.003.
7.
LeH.GhatakS.YeungC.TellkampF.GünschmannC.DieterichC.et al., Mechanical regulation of transcription controls Polycomb-mediated gene silencing during lineage commitment, Nature Cell Biology18 (2016), 864–875. doi:10.1038/ncb3387.
8.
BallaV.BodhakS.BoseS. and BandyopadhyayA., Porous tantalum structures for bone implants: Fabrication, mechanical and in vitro biological properties, Acta Biomateri.6 (2010), 3349–3359. doi:10.1016/j.actbio.2010.01.046.
9.
WenC.MabuchiM.YamadaY.ShimojimaK.ChinoY. and AsahinaT., Processing of Biocompatible Porous Ti and Mg, Vol. 45, Scripta Materialia, 2001, pp. 1147–1153. doi:10.1016/S1359-6462(01)01132-0.
10.
NarayananR.KwonT. and KimK., TiO2 nanotubes from stirred glycerol/NH4F electrolyte: Roughness, wetting behavior and adhesion for implant applications, Mater. Chem. Phys.117 (2009), 460–464. doi:10.1016/j.matchemphys.2009.06.023.
11.
LiY.LiB.FuX.LiJ.LiC.LiH.et al., Anodic oxidation modification improve bioactivity and biocompatibility of titanium implant surface, J. Hard Tissue Biol.22 (2013), 351–358. doi:10.2485/jhtb.22.351.
12.
LiB.HaoJ.MinY.XinS.GuoL.HeF.et al., Biological properties of nanostructured Ti incorporated with Ca, P and Ag by electrochemical method, Mater. Sci. Eng. C51 (2015), 80–86. doi:10.1016/j.msec.2015.02.036.
13.
SYBR® Select Master Mix user guide, applied biosystem, life technology, CA, USA, 2012.
14.
OliverW. and PharrG., An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments, J. Mater. Res.7 (1992), 1564–1583. doi:10.1557/JMR.1992.1564.
15.
KimM., Influence of substrates on the elastic reaction of films for the microindentation tests, Thin Solid Films283 (1996), 12–16. doi:10.1016/0040-6090(95)08498-3.
16.
ZhuH.NiuY.LinC.HuangL.JiH. and ZhengX., Microstructures and tribological properties of vacuum plasma sprayed B4C–Ni composite coatings, Ceramics International39 (2013), 101–110. doi:10.1016/j.ceramint.2012.05.101.
17.
LiB.LiY.MinY.HaoJ.LiangC.LiH.et al., Synergistic effects of hierarchical hybrid micro/nanostructures on the biological properties of titanium orthopaedic implants, RSC Adv.5 (2015), 49552–49558. doi:10.1039/C5RA05821J.
18.
PortanD.KroustalliA.DeligianniD. and PapanicolaouG., On the biocompatibility between TiO2 nanotubes layer and human osteoblasts, J. Biomed. Mater. Res. A100 (2012), 2546–2553. doi:10.1002/jbm.a.34188.
19.
BalasundaramG. and WebsterT.J., A perspective on nanophase materials for orthopedic implant applications, J. Mater. Chem.16 (2006), 3737–3745. doi:10.1039/b604966b.
