The Gingiva from the Tissue Surrounding the Bone to the Tissue Regenerating the Bone: A Systematic Review of the Osteogenic Capacity of Gingival Mesenchymal Stem Cells in Preclinical Studies

Table 1

Summary of findings for in vitro studies (methodology).

No.	Author and year of publication	Source of stem cells	Isolation method	Type of culture	Experimental groups			Osteogenic induction period (days)	Density of cells/well	Scaffold or carrier if present
					Stem cell-based intervention (source of interest)	Stem cell-based intervention (other sources)	Control group
In vitro studies without confirmation of an ectopic bone formation
1	Abedian et al. (2020) [59]	Human	Enzymatic	OIM	GMSCs	PDLSCs	Uninduced cells	14		—
2	Kamel et al. (2019) [64]	Human	Enzymatic	OIM	GMSCs	DPSCs	Uninduced cells	21		—
3	Sun et al. (2019) [44]	Mice	Enzymatic	OIM	GMSCs	BMSCs	Cell-free medium	21		—
4	Xing et al. (2019) [61]	Human	Enzymatic	OIM	GMSCs	DPSCs; PDLSCs	—	21		—
5	Angelopoulos et al. (2018) [56]	Human	Outgrowth	OIM	GMSCs	DPSCs	Cell-free medium	28		—
6	Zhang et al. (2018) [57]	Human	Enzymatic	OIM	GMSCs	DPSCs; PDLSCs; DFSCs; BMSCs; ADSCs; UCMSCs	—	28		—
7	Ghaderi et al. (2018) [53]	Human	Enzymatic	OIM	GMSCs	BFPMSCs	Uninduced cells	21		—
8	Aboushady et al. (2018) [62]	Rats	Enzymatic	OIM	GMSCs	BMSCs; SSMSCs	—	14		—
9	Ansari et al. (2017) [54]	Human	Enzymatic	OIM	GMSCs	BMSCs	Cell-free scaffold	28		Alginate-GelMA hydrogel
10	Kaibuchi et al. (2017) [46]	Mini pig	Enzymatic	OIM	GMSCs	BMSCs; ASCs; PSCs; PDLSCs	—	21		—
11	Gao et al. (2014) [55]	Human	Enzymatic	OIM	GMSCs	PDLSCs; DSCs	—	21		—
12	Gay et al. (2014) [49]	Human	Enzymatic^#	OIM	GMSCs	PDLSCs; DPSCs; BMSCs	Uninduced cells	28		—
13	Yang et al. (2013) [60]	Human	Enzymatic	OIM	GMSCs	PDLSCs	Uninduced cells	28		—
14	Moshaverinia et al. (2012) [45]	Human	Enzymatic	OIM	GMSCs	PDLSCs; BMSCs	Cell-free scaffold	28		3D alginate
In vitro studies confirmed the results by ectopic bone formation
15	Zorin et al. (2014) [63]	Human	Enzymatic	OIM	GMSCs	BMSCs	—	14		OCP ceramic granules B-TCP
16	Moshaverinia et al. (2013) [65]	Human	Enzymatic	OIM	GMSCs	PDLSCs; BMSCs	Cell-free scaffold	28		3D alginate microbeads
17	Otabe et al. (2012) [50]	Human	Enzymatic	OIM	GMSCs	DPSCs	—	21		B-TCP
18	Mensing et al. (2011) [47]	Horse	Enzymatic	OIM	GMSCs	PDLSCs; ScMSCs	Uninduced cells	35		—
19	Fournier et al. (2010) [51]	Human	Outgrowth^#	OIM	Induced GMPC	GMPC (in vitro); BMSCs (ectopic)	Gingival fibroblast (in vitro); Cell-free carrier (ectopic)	21		HA carrier
20	Tomar et al. (2010) [58]	Human	Enzymatic^##	OIM	GMSCs	BMSCs (ectopic)	Cell-free scaffold (ectopic)	21-25 (in vitro); 10 (ectopic)	(in vitro); (ectopic)	HA/TCP

The outgrowth method instead of the digestion method to obtain cells from PDL. Isolated cells were further selected via the single-cell cloning method. ^#Homogenous population of cells was obtained by fluorescence-activated cell sorting after the enzymatic isolation method. ^#GMSCs were obtained by the outgrowth method followed by colony-forming units. ^##GMSCs were obtained by two times the enzymatic method, while BMSCs were obtained by density gradient centrifugation using Ficoll-Hypaque.