An integrated approach to develop engineered metal composite bone scaffold with controlled degradation

Magnesium alloy based bioceramic reinforced degradable composite scaffolds were fabricated by use of powder metallurgy technique followed by controlled two stage heat treatment. Carbamide was introduced to create porosity in the scaffolds. Selective alloying elements such as calcium, zinc and iron were introduced in a systematic manner to control the degradation rate, while bioactivity was introduced by incorporating micro-hydroxyapatite particulates. Microstructure of fabricated scaffolds were studied by scanning electron microscopy which established predominantly homogeneous distribution of pores. X-ray micro computed tomography results indicated gradient porosities with variation in pore dimensions and shapes throughout the microstructure, an essential feature to biomimick the structure of bone. Degradation rate was evaluated by weight loss method following periodic immersion in Hanks solution. The results suggested controlled and enhanced degradation resistance of composite scaffolds. The results from this study therefore, could demonstrate promising potential of developed composites as lightweight bone scaffolds with tunable degradability.