Table 3.

Scaffold requirements for effective bone tissue regeneration.

Requirement	Description
Cytocompatibility	The released products should be non-toxic and non-inflammatory.
Bioactivity	Scaffold should interact with the tissue according to osteoinductive and osteoconductive principles.
Biodegradability	An ideal scaffold should degrade in a controlled way by external-enzymatic/biological process.
Suitable porosity	Interconnected pores are necessary for cell diffusion and migration. The scaffold should present micro porosity to guarantee enough surface area for its interaction with the tissue. Macro porosity is required for cell migration and cell growth. On the other hand, the porosity should not affect the mechanical stability.
Mechanical features	Scaffold should reproduce elastic and fatigue strength of the bones tissue site.
Tunable properties	Scaffold should have customizable properties.
Easy manufacturing, processing and handling	Scaffold should be easy to be fabricated and sterilized. Easy clinical manipulation is required.