title: Bone tissue response induced by bioactive polymer functionalized Ti6Al4V surfaces: In vitro and in vivo study.
abstract: Ti6Al4V is commonly used for orthopedic applications. This study was designed to test the potentially added benefit of Ti6Al4V functionalized with a bioactive polymer poly(sodium styrene sulfonate) both in vitro and in vivo. Cell-based assays with MC3T3-E1 osteoblast-like cells were used to measure the cell adhesion strength, cell spreading, focal contact formation, cell differentiation and the mineralization of extracellular matrix on grafted and ungrafted Ti6Al4V discs in combination with FBS and collagen type I. Bone morphogenetic protein-2 (BMP-2) was also included in the cell differentiation assay. Results showed that the grafted surface combined with collagen I gave superior levels in every parameter tested with cell-based assays and was almost equivalent to BMP-2 for cell differentiation. In vivo testing was conducted in rabbits (n=42) with cylinders of grafted and ungrafted Ti6Al4V implanted in defects made to the femoral and lateral condyles and animals that were maintained to 1, 3 and 12months. Hydroxyapatite coated Ti6Al4V cylinders were included as a clinical reference control. Osseointegration was assessed post-mortem using histomorphometric analysis conducted on resin sections of explanted undecalcified bone. Two histomorphometric parameters, that of bone-to-implant contact and the bone area, were analyzed by a trained observer blinded to sample identity. Results showed osseointegration on grafted Ti6Al4V was marginally better than both ungrafted and hydroxyapatite coated Ti6Al4V. Overall, the study found that the grafted Ti6Al4V significantly promoted all aspects of osteogenesis tested in vitro and, although in vivo outcomes were less compelling, histomorphometry showed osseointegration of grafted Ti6Al4V implants was equivalent or better than controls.
authors.affiliation: Laboratory of Biomaterials and Polymers of Specialty, LBPS-CSPBAT CNRS UMR 7244, Université Paris 13, Sorbonne Paris Cité, 93430 Villetaneuse, France. Electronic address: felgueiras.helena@gmail.com.
authors.forename: Helena P
authors.initials: HP
authors.lastname: Felgueiras
authors.affiliation: Laboratoire de Bioingénierie et Bioimagerie Ostéo-articulaires (B2OA), UMR 7052, Université Paris Diderot, 75010 Paris, France; École Nationale Vétérinaire d'Alfort, Service de Chirurgie, Université Paris Est, 94700 Maisons-Alfort, France.
authors.forename: Adeline
authors.initials: A
authors.lastname: Decambron
authors.affiliation: Laboratoire de Bioingénierie et Bioimagerie Ostéo-articulaires (B2OA), UMR 7052, Université Paris Diderot, 75010 Paris, France; École Nationale Vétérinaire d'Alfort, Service de Chirurgie, Université Paris Est, 94700 Maisons-Alfort, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Manassero
authors.affiliation: École Nationale Vétérinaire d'Alfort, Service de Chirurgie, Université Paris Est, 94700 Maisons-Alfort, France.
authors.forename: Louise
authors.initials: L
authors.lastname: Tulasne
authors.affiliation: CSIRO Biomedical Materials Program, 11 Julius Avenue, North Ride, Sydney, NSW 2113, Australia.
authors.forename: Margaret D M
authors.initials: MDM
authors.lastname: Evans
authors.affiliation: Laboratoire de Bioingénierie et Bioimagerie Ostéo-articulaires (B2OA), UMR 7052, Université Paris Diderot, 75010 Paris, France; École Nationale Vétérinaire d'Alfort, Service de Chirurgie, Université Paris Est, 94700 Maisons-Alfort, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Viateau
authors.affiliation: Laboratory of Biomaterials and Polymers of Specialty, LBPS-CSPBAT CNRS UMR 7244, Université Paris 13, Sorbonne Paris Cité, 93430 Villetaneuse, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Migonney
mesh_terms: D000497:Alloys; D000818:Animals; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D005260:Female; D051379:Mice; D010012:Osteogenesis / Q000187:drug effects; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology*; D011817:Rabbits; D013499:Surface Properties; D014025:Titanium / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D000497:Alloys; D011108:Polymers; C031462:titanium alloy (TiAl6V4); D014025:Titanium
keywords: Bone morphogenetic protein-2; Collagen type I; Osseointegration; Osteogenesis; Poly(sodium styrene sulfonate) grafting; Ti6Al4V