TABLE 2.

Characteristics of the outlined synthetic polymers for CTE.

Biomaterials	Symbol	Characteristics	Advantages	Disadvantages	References
Poly(glycolic acid)	PGA	Linear, crystalline hydrophobic polyester; Semicrystalline polymer; Insoluble in most organic solvents	Biocompatibility; Availability; Easy processing; Composited with other biomaterials	Release of acidic degradation products; Poor cell adhesion; Fast biodegradability; Low mechanical properties	Klein et al. (2005), Zwingmann et al. (2007), Nakao et al. (2017), Birru et al. (2018)
Poly(lactic acid)	PLA	Polyesterification reaction production of lactic acid; Lower crystallinity and hydrophilicity than PGA; Four different forms	Biocompatibility, controllable biodegradability; Low toxicity and viscosity; Favorable mechanical properties; Thermostability; Thermoplasticity	Poor cell adhesion	Li et al. (2006), Zwingmann et al. (2007), Lopes et al. (2012), Revati et al. (2017), Smieszek et al. (2019), Szyszka et al. (2019), Marycz et al. (2020)
Poly(ethylene glycol)	PEG	An amphiphilic polymer that cannot be recognized by the immune system	Biocompatibility; Biodegradability; Non-immunogenic; Promoting chondrogenesis; Great flexibility; Low polydispersity	Poor cell adhesion	Karim et al. (2016), Ding and Li (2017), Cheng et al. (2018), Cheng H. et al. (2019), Li et al. (2018), Wang et al. (2019)
Poly-ε-caprolactone	PCL	Semi-crystalline; A synthetic polyester polymer	Biocompatibility; Biodegradability; Elasticity; Excellent mechanical properties; Thermoplastic	Poor hydrophilicity; Poor cell adhesion	Ousema et al. (2012), Sousa et al. (2014), Theodoridis et al. (2019), Venkatesan et al. (2020)