Osteointegration Characterization of Additive Manufactured Porous Titanium Scaffold Based on Microhardness and Ca/P Ratio

Additive technologies are getting widely used in orthopedics due to the opportunity of full modelling of complex cellular structures and producing personalized implants. Titanium and its alloys are still the main material used for metallic implants manufacturing. In this study microhardness and Ca/P ratio of bone tissue surrounding the implant were investigated. By means of ABAQUS software titanium porous structure implants were designed. Their biomechanical properties were close to biomechanical properties of trabecular bone tissue. Direct metal laser sintering (DMLS) was used to manufacture implants from Ti-6Al-4V titanium alloy. They were augmented in trabecular bone defects of Chinchilla rabbits for 6, 12 and 25 weeks. The samples were examined by scanning electron microscopy (SEM) in a FEG SEM ZEISS CrossBeam AURIGA and the Ca/P ratio was calculated using the accompanying Oxford Inca software. Vickers hardness test method was performed for microhardness. It was shown that there was a significant increase in both mineral and mechanical properties of bone samples with an increase of observation period. The results found in this study illustrate a distinct relationship between the mineralization parameter of bone tissue and its microhardness (r = 0.808, r2 = 0.65). Keywords: Scaffold, Microhardness, Titanium, Ca/P ratio, Bone defect, Osteointegration, Additive manufacturing