title: Mechanical compatibility of sol-gel annealing with titanium for orthopaedic prostheses.
abstract: Sol-gel processing is an attractive method for large-scale surface coating due to its facile and inexpensive preparation, even with the inclusion of precision nanotopographies. These are desirable traits for metal orthopaedic prostheses where ceramic coatings are known to be osteoinductive and the effects may be amplified through nanotexturing. However there are a few concerns associated with the application of sol-gel technology to orthopaedics. Primarily, the annealing stage required to transform the sol-gel into a ceramic may compromise the physical integrity of the underlying metal. Secondly, loose particles on medical implants can be carcinogenic and cause inflammation so the coating needs to be strongly bonded to the implant. These concerns are addressed in this paper. Titanium, the dominant material for orthopaedics at present, is examined before and after sol-gel processing for changes in hardness and flexural modulus. Wear resistance, bending and pull tests are also performed to evaluate the ceramic coating. The findings suggest that sol-gel coatings will be compatible with titanium implants for an optimum temperature of 500 °C.
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK. andrew.greer@glasgow.ac.uk.
authors.forename: Andrew I M
authors.initials: AI
authors.lastname: Greer
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: Teoh S
authors.initials: TS
authors.lastname: Lim
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: Alistair S
authors.initials: AS
authors.lastname: Brydone
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: Nikolaj
authors.initials: N
authors.lastname: Gadegaard
mesh_terms: D005782:Gels; D006245:Hardness Tests; D009985:Orthopedics; D056951:Photoelectron Spectroscopy; D019736:Prostheses and Implants; D013059:Spectrum Analysis, Raman; D013818:Thermogravimetry; D014025:Titanium
chemical_list: D005782:Gels; D014025:Titanium