In vitro characterization of bioactive titanium dioxide/hydroxyapatite surfaces functionalized with BMP-2.
Poor implant fixation and bone resorption are two of the major challenges in modern orthopedics and are caused by poor bone/implant integration. In this work, bioactive crystalline titanium dioxide (TiO(2))/hydroxyapatite (HA) surfaces, functionalized with bone morphogenetic protein 2 (BMP-2), were evaluated as potential implant coatings for improved osseointegration. The outer layer consisted of HA, which is known to be osteoconductive, and may promote improved initial bone attachment when functionalized with active molecules such as BMP-2 in a soaking process. The inner layer of crystalline TiO(2) is bioactive and ensures long-term fixation of the implant, once the hydroxyapatite has been resorbed. The in vitro response of mesenchymal stem cells on bioactive crystalline TiO(2)/HA surfaces functionalized with BMP-2 was examined and compared with the cell behavior on nonfunctionalized HA layers, crystalline TiO(2) surfaces, and native titanium oxide surfaces. The crystalline TiO(2) and the HA surfaces showed to be more favorable than the native titanium oxide surface in terms of cell viability and cell morphology as well as initial cell differentiation. Furthermore, cell differentiation on BMP-2-functionalized HA surfaces was found to be significantly higher than on the other surfaces indicating that the simple soaking process can be used for incorporating active molecules, promoting fast bone osseointegration to HA layers.
Piskounova
Sonya
S
Division for Polymer Chemistry, Department of Materials Chemistry, The Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden.
Forsgren
Johan
J
Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden.
Brohede
Ulrika
U
Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden.
Engqvist
Håkan
H
Division for Materials Science, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden.
Strømme
Maria
M
Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden.
D000469:Alkaline Phosphatase / Q000378:metabolism; D055396:Bone Morphogenetic Protein 2 / Q000737:chemistry*; D002454:Cell Differentiation; D002470:Cell Survival; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D006801:Humans; D059630:Mesenchymal Stem Cells; D008855:Microscopy, Electron, Scanning; D010100:Oxygen / Q000032:analysis; D013242:Sterilization; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
D055396:Bone Morphogenetic Protein 2; D020099:Coated Materials, Biocompatible; C009495:titanium dioxide; D017886:Durapatite; D014025:Titanium; D000469:Alkaline Phosphatase; D010100:Oxygen