Evaluation of a high-velocity flame-spraying technique for hydroxyapatite

Titanium alloy sprayed with hydroxyapatite (HA) was developed by a high-velocity flame-spraying technique (HVFST). Biocompatible responses of bony tissues to high-velocity flame-sprayed HA (HVFS-HA) implanted into tibias of adult male rabbits was investigated 4 and 18 months after implantation by light and electron microscopy. Both light and electron microscope features in histological sections showed that inflammatory responses of tissues in situ were completely cleared and the interface between the bone and the implant was filled with newly formed bony substrate. This suggests that the HVFS-HA was sufficiently biocompatible to be adapted to the bone in situ.