title: Enhanced osteogenesis on titanium implants by UVB photofunctionalization of hydrothermally grown TiO₂ coatings.
abstract: Even though Ti-based implants are the most used materials for hard tissue replacement, they may present lack of osseointegration on the long term, due to their inertness. Hydrothermal treatment (HT) is a useful technique for the synthesis of firmly attached, highly crystalline coatings made of anatase titanium dioxide (TiO2), providing favorable nanoroughness and higher exposed surface area, as well as greater hydrophilicity, compared to the native amorphous oxide on pristine titanium. The hydrophilicity drops even more by photofunctionalization of the nanostructured TiO2-anatase coatings under UV light. Human mesenchymal stem cells exhibited a good response to the combination of the positive surface characteristics, especially in respect to the UVB pre-irradiation. The results showed that the cells were not harmed in terms of viability; even more, they were encouraged to differentiate in osteoblasts and to become osteogenically active, as confirmed by the calcium ion uptake and the formation of well-mineralized, bone-like nodule structures. In addition, the enrichment of hydroxyl groups on the HT-surfaces by UVB photofunctionalization accelerated the cell differentiation process and greatly improved the osteogenesis in comparison with the nonirradiated samples. The optimal surface characteristics of the HT-anatase coatings as well as the high potentiality of the photo-induced hydrophilicity, which was reached during a relatively short pre-irradiation time (5 h) with UVB light, can be correlated with better osseointegration ability in vivo; among the samples, the superior biological behavior of the roughest and most hydrophilic HT coating makes it a good candidate for further studies and applications.
authors: Department of Nanostructured Materials, Jožef Stefan Institute, Ljubljana, Slovenia Jožef Stefan International Postgraduate School, Ljubljana, Slovenia martina.lorenzetti@ijs.si.
authors: Martina
authors: M
authors: Lorenzetti
authors: Laboratory for Experimental Trauma Surgery, Justus-Liebig-University Giessen, Giessen, Germany.
authors: Olga
authors: O
authors: Dakischew
authors: Laboratory for Experimental Trauma Surgery, Justus-Liebig-University Giessen, Giessen, Germany.
authors: Katja
authors: K
authors: Trinkaus
authors: Laboratory for Experimental Trauma Surgery, Justus-Liebig-University Giessen, Giessen, Germany.
authors: Katrin Susanne
authors: KS
authors: Lips
authors: Laboratory for Experimental Trauma Surgery, Justus-Liebig-University Giessen, Giessen, Germany Department of Trauma Surgery, University Hospital of Giessen and Marburg, Giessen, Germany.
authors: Reinhard
authors: R
authors: Schnettler
authors: Department of Nanostructured Materials, Jožef Stefan Institute, Ljubljana, Slovenia Jožef Stefan International Postgraduate School, Ljubljana, Slovenia.
authors: Spomenka
authors: S
authors: Kobe
authors: Department of Nanostructured Materials, Jožef Stefan Institute, Ljubljana, Slovenia Jožef Stefan International Postgraduate School, Ljubljana, Slovenia.
authors: Saša
authors: S
authors: Novak
mesh_terms: D002118:Calcium / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D049329:Nanostructures / Q000737:chemistry; D010006:Osteoblasts / Q000166:cytology; D010012:Osteogenesis / Q000187:drug effects*; D019736:Prostheses and Implants; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry / Q000378:metabolism*; D014466:Ultraviolet Rays
chemical_list: D020099:Coated Materials, Biocompatible; C009495:titanium dioxide; D014025:Titanium; D002118:Calcium
keywords: TiO2; biocompatibility; bone; hMSCs; hydrothermal treatment; osteogenesis; photofunctionalization