Requirements for scaffolds in bone-tissue engineering

The evolution of bone graft biomaterials can be categorized into four different generations (Fig. 15.2) [1,11]. 

The first-generation bone grafts are metals and alloys (stainless steel, titanium alloys, etc. [1]) which have excellent mechanical properties but are neither bioresorbable nor bioactive. Their lifetime is limited and hence need to be removed and replaced 

Insert metals and alloys Bloactive ceramics bioresorbable polymers Bloactive/ bioresorbable ceramic-polymer composites Tissue-engineered nanooomposite, Incorporating oells and growth faotors 

Scaffolds for bone-tissue engineering must fulfil some primary functions  

BiocompatibiUty scaffolds should be weU integrated in the host s tissue without any immune response or toxic effects  

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