Table 2.

General properties for scaffolds and challenges

General Properties Of Scaffolds	Challenges	References
Biocompatibility	• Non-controlling degradation of biodegradable polymers in vivo	[103, 104]
	• The toxicity of products produced by the degradation of biocompatible polymers
	• Low cell seeding efficiency
Mechanical Properties proper for tissue	• Scaffolding design with mechanical properties proportional to tissue	[29, 38]
	• Mechanical integrity
	• Protect cells against tensile and pressing forces
Biodegradability	• The completion of the tissue healing is dependent on the rate of biodegradation	[105, 106]
	• At least toxicity and inflammation
	• Transmit the tissue growth conduction signals and differentiation
	• Cell migration
	• Pore size and porosity proportional to the tissue
Porous interconnectivity	• At least toxicity and inflammation	[105, 106]
	• Transmit the tissue growth conduction signals and differentiation
	• Pore size and porosity proportional to the tissue
	• The possibility of exchanging gases, nutrients and growth factors and waste materials
	• Cell migration
Chemical surface and topography	• Cell-cell interactions and cell adhesion, controlling cell function	[91, 107]