Osteoblast response to thermally oxidized Ti6Al4V alloy.
We have recently reported that thermal oxidation treatments of Ti6Al4V at 500 degrees and 700 degrees C for 1 h result in the formation of an outer "ceramic" layer of rutile that do not decrease the high in vitro corrosion resistance of the alloy. In the present work, surface roughness was measured and found marginally increased as a consequence of oxidation of the alloy at 700 degrees C, but not at 500 degrees C. We have evaluated the biocompatibility of the oxidized surfaces, by assessing cell adhesion, proliferation, and differentiation of primary cultures of human osteoblastic cells. Compared with polished alloy, both thermal treatments increased osteoblast adhesion measured as cell attachment, beta1 integrin and FAK-Y397 expression, as well as cytoskeletal reorganization. Compared with treatment at 500 degrees C, thermal oxidation at 700 degrees C enhanced cell adhesion. Treatment at 700 degrees C transiently impaired cell proliferation and viability, which were not altered in alloys oxidized at 500 degrees C. Several markers of osteoblastic differentiation such as procollagen I peptide, alkaline phosphatase, osteocalcin, and mineralized nodule formation were found either unaffected or differentially increased by alloys treated either at 500 degrees or 700 degrees C. In addition, thermal oxidation at 700 degrees C also increased osteoprotegerin secretion. Taken together, our results indicate that thermal oxidation treatments at 500 degrees or 700 degrees C for 1 h improve the in vitro biocompatibility of Ti6Al4V.
Saldaña
L
L
Unidad de Investigación, Hospital La Paz, Paseo de la Castellana 261, 28046 Madrid, Spain.
Vilaboa
N
N
Vallés
G
G
González-Cabrero
J
J
Munuera
L
L
D000199:Actins / Q000378:metabolism; D000368:Aged; D000497:Alloys; D001842:Bone and Bones / Q000166:cytology; D002113:Calcification, Physiologic / Q000187:drug effects; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D006801:Humans; D039641:Integrin beta Chains / Q000378:metabolism; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D010084:Oxidation-Reduction; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D013696:Temperature; D014025:Titanium / Q000737:chemistry* / Q000494:pharmacology*
D000199:Actins; D000497:Alloys; D039641:Integrin beta Chains; C031462:titanium alloy (TiAl6V4); D014025:Titanium; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496050:PTK2 protein, human