title: Electrochemical growth behavior, surface properties, and enhanced in vivo bone response of TiO2 nanotubes on microstructured surfaces of blasted, screw-shaped titanium implants.
abstract: TiO(2) nanotubes are fabricated on TiO(2) grit-blasted, screw-shaped rough titanium (ASTM grade 4) implants (3.75 x 7 mm) using potentiostatic anodization at 20 V in 1 M H(3)PO(4) + 0.4 wt.% HF. The growth behavior and surface properties of the nanotubes are investigated as a function of the reaction time. The results show that vertically aligned nanotubes of approximately 700 nm in length, with highly ordered structures of approximately 40 nm spacing and approximately 15 nm wall thickness may be grown independent of reaction time. The geometrical properties of nanotubes increase with reaction time (mean pore size, pore size distribution [PSD], and porosity approximately 90 nm, approximately 40-127 nm and 45%, respectively for 30 minutes; approximately 107 nm, approximately 63-140 nm and 56% for one hour; approximately 108 nm, approximately 58-150 nm and 60% for three hours). It is found that the fluorinated chemistry of the nanotubes of F-TiO(2), TiOF(2), and F-Ti-O with F ion incorporation of approximately 5 at.%, and their amorphous structure is the same regardless of the reaction time, while the average roughness (Sa) gradually decreases and the developed surface area (Sdr) slightly increases with reaction time. The results of studies on animals show that, despite their low roughness values, after six weeks the fluorinated TiO(2) nanotube implants in rabbit femurs demonstrate significantly increased osseointegration strengths (41 vs 29 Ncm; P = 0.008) and new bone formation (57.5% vs 65.5%; P = 0.008) (n = 8), and reveal more frequently direct bone/cell contact at the bone-implant interface by high-resolution scanning electron microscope observations as compared with the blasted, moderately rough implants that have hitherto been widely used for clinically favorable performance. The results of the animal studies constitute significant evidence that the presence of the nanotubes and the resulting fluorinated surface chemistry determine the nature of the bone responses to the implants. The present in vivo results point to potential applications of the TiO(2) nanotubes in the field of bone implants and bone tissue engineering.
authors.affiliation: Department of Biomaterials/Handicap Research, Institute for Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden. young-taeg.sul@biomaterials.gu.se
authors.forename: Young-Taeg
authors.initials: YT
authors.lastname: Sul
mesh_terms: D000818:Animals; D001863:Bone Screws; D003460:Crystallization / Q000379:methods; D004563:Electrochemistry / Q000379:methods; D019544:Equipment Failure Analysis; D005269:Femur / Q000473:pathology / Q000502:physiology* / Q000601:surgery*; D046911:Macromolecular Substances / Q000737:chemistry; D008297:Male; D008422:Materials Testing; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D010012:Osteogenesis / Q000502:physiology*; D010316:Particle Size; D011474:Prosthesis Design; D011817:Rabbits; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; C009495:titanium dioxide; D014025:Titanium
references.citation: Clin Oral Implants Res. 2009 Oct;20(10):1146-55
references.pmid: 19719742
references.citation: Small. 2009 Mar;5(6):666-71
references.pmid: 19235196
references.citation: Int J Oral Maxillofac Implants. 2005 May-Jun;20(3):349-59
references.pmid: 15973946
references.citation: Nano Lett. 2007 Jun;7(6):1686-91
references.pmid: 17503870
references.citation: J Oral Pathol. 1982 Aug;11(4):318-26
references.pmid: 6809919
references.citation: Chem Commun (Camb). 2009 May 28;(20):2791-808
references.pmid: 19436878
references.citation: Biomaterials. 2002 Nov;23(21):4211-9
references.pmid: 12194524
references.citation: Chem Rev. 2007 Jul;107(7):2891-959
references.pmid: 17590053
references.citation: J Nanosci Nanotechnol. 2006 Sep-Oct;6(9-10):2682-92
references.pmid: 17048475
references.citation: Biomaterials. 2003 Oct;24(22):3893-907
references.pmid: 12834584
references.citation: Proc Natl Acad Sci U S A. 2009 Jun 16;106(24):E60; author reply E61
references.pmid: 19506261
references.citation: J Mater Sci Mater Med. 2001 Oct-Dec;12(10-12):1025-31
references.pmid: 15348359
references.citation: J Biomed Mater Res A. 2009 Mar 1;88(3):561-8
references.pmid: 18306319
references.citation: J Dent Res. 2006 Jun;85(6):496-500
references.pmid: 16723643
references.citation: Biomaterials. 2005 Nov;26(33):6720-30
references.pmid: 15975649
references.citation: Clin Implant Dent Relat Res. 2004;6(2):101-10
references.pmid: 15669710
references.citation: J R Soc Interface. 2010 Jan 6;7(42):81-90
references.pmid: 19369221
references.citation: J Biomed Mater Res A. 2009 Jun 15;89(4):942-50
references.pmid: 18470920
references.citation: Small. 2009 May;5(9):996-1006
references.pmid: 19360718
references.citation: Int J Oral Maxillofac Implants. 2002 Sep-Oct;17(5):625-34
references.pmid: 12381062
references.citation: Clin Oral Implants Res. 2002 Jun;13(3):252-9
references.pmid: 12010155
references.citation: Proc Natl Acad Sci U S A. 2009 Feb 17;106(7):2130-5
references.pmid: 19179282
references.citation: Biomaterials. 2006 Feb;27(6):926-36
references.pmid: 16112191
references.citation: Biomaterials. 2002 Apr;23(8):1809-17
references.pmid: 11950051
references.citation: Clin Oral Implants Res. 2006 Oct;17(5):521-6
references.pmid: 16958691
references.citation: J Mater Sci Mater Med. 2004 Sep;15(9):1031-5
references.pmid: 15448411
references.citation: J Orthop Res. 2007 Jan;25(1):11-22
references.pmid: 17048259
references.citation: Med Eng Phys. 2001 Jun;23(5):329-46
references.pmid: 11435147
references.citation: Int J Prosthodont. 2006 Jul-Aug;19(4):319-28
references.pmid: 16900812
references.citation: Biomaterials. 1996 Jan;17(1):15-22
references.pmid: 8962942
references.citation: Biomaterials. 2002 Jan;23(2):491-501
references.pmid: 11761170
references.citation: J Biomed Mater Res B Appl Biomater. 2009 Apr;89(1):165-71
references.pmid: 18780361
references.citation: Biomaterials. 2005 Aug;26(22):4516-22
references.pmid: 15722120
references.citation: J Biomed Mater Res. 1999 May;45(2):75-83
references.pmid: 10397960
references.citation: Clin Implant Dent Relat Res. 2002;4(2):78-87
references.pmid: 12121607