Tailor-made natural and synthetic grafts for precise urethral reconstruction

Table 1 Overview of studies describing the use of scaffold-free grafts in urethral reconstruction

Scaffold-free grafts	Biomaterials	Clinical/preclinical experiment	Animals for modeling	Average repair length	Follow-up/study period	In vivo/In vitro	Results	References
Flaps and patches	Dorsal penile flap	Clinical	NA	5 cm	3years	In vivo	Overall success rate is 88%; restore urethra function; provide cosmetic effects	[21]
	Oral mucosal grafts	Clinical	NA	3–5 cm	At least 1year	In vivo	overall success rate is 85%; reduced operation time	[24]
	BM	Preclinical	Rabbit	1.5 cm	3months	In vivo	induce angiogenesis; repair urethra tissue effectively	[27]
	Skeletal muscle	Preclinical	Rabbit	0.5 cm	12 weeks	In vivo	provide a large amount of angiogenic cytokines highly vascularized porosity flexibility;	[32]
	Induced microtissues	Preclinical	NA	NA	NA	In vivo	functional layering; single continuous urothelium	[34]
Cell sheet grafts	Oral epithelial cell and muscle cells	Preclinical	Canine	2 cm	12 weeks	In vivo	stratified urothelium intact muscle layer wide caliber	[36]
	Fibroblasts, ECs and UCs	Preclinical	NA	NA	NA	In vivo	promote the formation of blood vessel reduce necrosis;	[37]
	Bidirectionally induced ADSCs	Preclinical	Rabbit	2 cm	6months	In vivo	stable multilayer epithelial cell layer; significant vascularization; Visible smooth muscle layer	[39]
	Oral mucosal epithelial cells, oral fibroblasts and ADSCs	Preclinical	Canine	2 cm	3 months	In vivo	regenerated tissue similar to natural urethra	[40]

ISSN: 1477-3155