title: Nanostructured glass-ceramic coatings for orthopaedic applications.
abstract: Glass-ceramics have attracted much attention in the biomedical field, as they provide great possibilities to manipulate their properties by post-treatments, including strength, degradation rate and coefficient of thermal expansion. In this work, hardystonite (HT; Ca2ZnSi2O7) and sphene (SP; CaTiSiO5) glass-ceramic coatings with nanostructures were prepared by a plasma spray technique using conventional powders. The bonding strength and Vickers hardness for HT and SP coatings are higher than the reported values for plasma-sprayed hydroxyapatite coatings. Both types of coatings release bioactive calcium (Ca) and silicon (Si) ions into the surrounding environment. Mineralization test in cell-free culture medium showed that many mushroom-like Ca and phosphorus compounds formed on the HT coatings after 5 h, suggesting its high acellular mineralization ability. Primary human osteoblasts attach, spread and proliferate well on both types of coatings. Higher proliferation rate was observed on the HT coatings compared with the SP coatings and uncoated Ti-6Al-4V alloy, probably due to the zinc ions released from the HT coatings. Higher expression levels of Runx2, osteopontin and type I collagen were observed on both types of coatings compared with Ti-6Al-4V alloy, possibly due to the Ca and Si released from the coatings. Results of this study point to the potential use of HT and SP coatings for orthopaedic applications.
authors.affiliation: Biomaterials and Tissue Engineering Research Unit, School of AMME, University of Sydney, Sydney 2006, Australia.
authors.forename: Guocheng
authors.initials: G
authors.lastname: Wang
authors.forename: Zufu
authors.initials: Z
authors.lastname: Lu
authors.forename: Xuanyong
authors.initials: X
authors.lastname: Liu
authors.forename: Xiaming
authors.initials: X
authors.lastname: Zhou
authors.forename: Chuanxian
authors.initials: C
authors.lastname: Ding
authors.forename: Hala
authors.initials: H
authors.lastname: Zreiqat
mesh_terms: D000497:Alloys; D000943:Antigens, Differentiation / Q000096:biosynthesis; D002118:Calcium / Q000737:chemistry* / Q000378:metabolism; D002478:Cells, Cultured; D002516:Ceramics / Q000737:chemistry*; D020099:Coated Materials, Biocompatible; D005786:Gene Expression Regulation; D006801:Humans; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry*; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D019736:Prostheses and Implants; D014025:Titanium
chemical_list: D000497:Alloys; D000943:Antigens, Differentiation; D020099:Coated Materials, Biocompatible; C031462:titanium alloy (TiAl6V4); C023506:Glass ceramics; D014025:Titanium; D002118:Calcium