Table 1.

Scaffolds used in tissue engineering.

Material	Advantages	Limitations	References
Natural and Natural-Derived Polymeric Scaffolds
Polysaccharides	Derived from renewable sources	Batch-to-batch variation	[14,15]
	Biocompatibility	Poor mechanical properties
	Low cost
Alginate	Biocompatibility	Low mechanical strength	[16,17]
	Low immunogenicity	Uncontrolled biodegradation rate
	Degradation by enzymolysis
	Large diversity
Chitosan	Biocompatibility	Allergies	[18,19]
	Biodegradable
	Antimicrobial potential
	Regenerative properties
	Ability to bind GF, glycosaminoglycans and DNA
	Different forms
Cellulose	Biocompatibility	Biodegradation in humans (limited or absent)	[20,21]
	Non-toxic	Poor mechanical properties
	High tensile strength
	Pliable
Extracelullar Matrix Derived	Dynamic environment	Batch-to-batch variation	[16]
	Composition can be adjusted	Processing and sterilizing difficulties
	Capacity to incorporate and release growth factors
Hyaluronic acid	Biocompatibility	High degradation rate	[17,22]
	Low immunogenicity	Poor mechanical properties
Collagen	Biocompatibility	Poor mechanical properties upon hydration	[23,24]
	Low immunogenicity	Difficult to customize
	Osteoblastic differentiation stimulant
	Easy placement of cells and GF
	Natural replacement after degradation
Gelatin	Biocompatibility	Sensitive to temperature alterations	[20,25]
	Low antigenicity	Degradation over time
	Wide availability
	Low cost
	Access to several functional groups for biochemical modification
Proteins and Peptides	Dynamic environment	Processing and sterilizing difficulties	[26,27]
	Biocompatibility
	Biodegradation
	Provide chemical signals to guide cell behavior
	Possible refinement of their structures with molecular manipulation
Fibrin	Injectable and molded to acquire desirable 3D forms Reproducible	Poor mechanical properties—low mechanical stiffness	[19,28,29,30,31]
	Low cost	Rapid degradation
	Autologous source—no immunologic risk
Silk	Biocompatibility	Irritant sericin coating	[17,32,33]
	Biodegradable
	Non immunogenic
	Low cost
	Available
	Remarkable mechanical properties
	Different forms
Self-assembling peptides	Biocompatibility	High cost	[34,35]
	Biodegradable	Complex design parameters
	Non immunogenic
	Easy to use (injectable)
	Nanometric
	More natural 3D microenvironment
Host-derived scaffolds	Autologous source—no immunologic risk	Specific equipment and reagents are mandatory.	[36]
Platelet-Rich Plasma (PRP)	Favorable for tissue growth
Platelet-Rich Fibrin (PRF)	Controlled growth factor release
Decellularized extracelullar matrix (ECM)	Adaptable into specific shapes
Treated dentin matrix (TDM)	Low costs
Synthetic-Engineered Polymeric and Ceramic Scaffolds
Synthetic Polymers	Biocompatibility	Lack physiological and chemical information	[37,38]
Polylactic acid (PLA)	Mild inflammation
Polyglycolic acid (PGA)	Low cost
Polylactide-co-glycolide (PLGA)	Reproducible
	Tailorable mechanical properties
	Biodegradable—degradation products are natural metabolites
Bioactive Ceramics		Brittleness	[37,39,40]
Calcium Phosphates	Biocompatibility	High density
Hydroxyapatite (HA)	Low immunogenicity	Low resilience
Tricalcium Phosphate (TCP)	Osteoconductivity	Poor mechanical properties
	Good resistance
Bioactive Glasses	Surface apatite layer formation	Poor mechanical properties	[41]
	Stimulates osteoblastic activity	Brittleness
		Density
		Low degradation rate