High energy ball-mill behavior of titania+hydroxyapatite composite nano-powders

摘要

Titanium (Ti) was proven to be a potentially suitable material for load bearing bioimplant applications, and was first introduced as a dental implant in the 1970's [1,2]. Titania (TiO_2) layers, which are naturally formed or artificially coated on the surface of Ti, determine to a great extent the long-term biocompatibility of the Ti implant, due to their direct contact with surrounding tissues. These layers have demonstrated promising in vivo corrosion behavior, by acting as a chemical barrier against the release of metal ions from the implant [3]. However, TiO_2 is bioinert, and thus its chemical bond with living bones in the body is not very strong [4,5]. This drawback has been addressed by coating Ti with a layer of bioceramic hydroxyapatite (HA), which is a main component of bone. HA attracts considerable interest owing to its excellent biocompatibility [1,5], but it is too brittle to be used under loaded conditions, thereby resulting in an early degradation and failure of the implant [6,7].