Summary: | 碩士 === 國立中興大學 === 材料工程學研究所 === 93 === By adjusting and controlling electrochemical factors and annealing temperatures, the calcium phosphate (CaP) with various surface morphology (roughness) and chemical compositions (HA, HA +β-TCP) were prepared on the post TiO2 coated Ti-6Al-4V alloys. The prepared CaP/TiO2/Ti-6Al-4V specimens were characterized by XRD, SEM/EDS analysis, dynamic polarization tests, immersion test, tensile test, cell culture for MTT (mitochondrial activity assay) and ALP (alkaline phosphatase activity ), and implantation in tibia of pig for in vivo tests. The HA+β-TCP/TiO2 coated specimen can retard ion release effectively. Through the tensile tests, it was found that the adhesion strength of HA coatings on Ti-6Al-4V alloys was enhanced from 20.42 MPa to 41.56 MPa by the intermediate TiO2 coating. No deteration of adhesion strength was found after 5 min ultrasonic vibration. In MTT assays, the calcium phosphate (CaP) coated specimens reveled more proliferation then the others after 5 days cell culture. The HA/TiO2 coated specimens after ultrasonic vibration revealed the best bioactivity in ALP assays. The release torque of screws after implanted for 8 weeks were 14, 18 and 24 Nt-cm for the uncoated, TiO2, and HA/TiO2 coated specimens, respectively. From the history observation, the HA/TiO2 coated screw also revealed the best osteointegration.
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