Investigation of antibacterial HA, coating material on Ti implant

Objectives: The objective is to study a novel Ti implant coated by silver containing antibacterial HA. Methods:1. The minimal bactericidal concentration(MBC) of silver-zirconium phosphate antimicrobial to peri-implant bacteria Pg, Fn, Aa was determined. 2. Four groups of Ti coated by HA which contained 0%, 2%, 5% and 10% (wt%) antimicrobial were fabricated by vacuum plasma spraying. The microstructure of coating material was observed under SEM and components were detected by electron probe. And the crystal was detected by x-ray diffractive methods. 3. Colonies of Aa, Fn, Pg on different samples cultured in the anaerobic glove box were counted. The antibacterial rate of each group was calculated and compared. Results: 1.MBC of the antimicrobial to Aa, Fn, Pg were 0.625mg/ml,0.313mg/ml,0.039mg/ml respectively. 2.The microstructure of HA contained 2%, 5% and 10% antimicrobial was the same as that of pure HA. There was globular granule with some caky and air bubble in the coating material. Crystal of 2% and 5% antimicrobial groups was the same as that of 0% group, the peak value reduced while proportion of antimicrobial increased. New crystal such as Na6CaP2O9 appeared in the components of the HA contained 10% antimicrobial. Electron probe detection showed no detectable Ag+ in the 2% antimicrobial group while contents of Ag+ in the 5% and 10% antimicrobial groups were approximate.3.The coating material was antibacterial to Pg, Fn and Aa while the proportion of the antimicrobial was equal to or higher than 5%. The antibacterial rate against Pg was higher than that against Aa and Fn. The 5% and 10% antimicrobial groups showed the same antibacterial ability to the three kinds of bacteria. Conclusions: Ti implant coated by antibacterial HA can inhibit the invasion of the peri-implant bacteria effectively. This novel material has the satisfying physical and chemical property.