Adult stem cell-based apexogenesis

Table 1 Adult stem cell candidates

	BMMSCs	DPSCs	SCAPs	SHEDs	PDLSCs	DFPCs
Location	Bone marrow	Permanent tooth pulp	Apical papilla of developing root	Exfoliated deciduous tooth pulp	Periodontal ligament	Dental follicle
Specific markers	ND	ND	CD24	ND	ND	GoPro49
Proliferation rate	Moderate	High	High	High	High	High
Multi-potentiality	Odontoblasts, osteoblasts, adipocytes, chondrocytes, myocytes, neurocytes, tenocytes	Odontoblasts, osteoblasts, adipocytes, chondrocytes, myocytes, neurocytes	Odontoblasts, osteoblasts, adipocytes, chondrocytes, neurocytes	Odontoblasts, osteoblasts, adipocytes, chondrocytes, myocytes, neurocytes	Osteoblasts, chondrocytes, adipocytes, neurocytes, cementoblasts	Osteoblasts, chondrocytes, cementoblasts, adipocytes, PDL fibroblasts, neuron-like cells
In vivo transplantation	Dentin-pulp-like tissue, bone, cementum, PDL	Dentin-pulp complex, bone	Dentin-pulp-like complex, bone	Dentin-like tissue, bone	Cementum/PDL-like structure	Cementum-like structure, bone

ND: Not determined; BMMSCs: Bone marrow mesenchymal stem cells; DPSCs: Dental pulp stem cells; SCAPs: Stem cells from apical papilla; SHEDs: Stem cells from human exfoliated deciduous teeth; PDL: Periodontal ligament; PDLSCs: Periodontal ligament stem cells; DFPCs: Dental follicle precursor cells.

Table 2 Comparison of in vivo transplantation outcomes of mesenchymal stem cells from different researchers

Ref.	MSCs	Outcomes
Ohazama et al[42]	BMMSCs	Tooth structures and associated bone
Li et al[28]	BMMSCs	Tooth-like structures surrounded by bone and soft tissues
Kawaguchi et al[43]	BMMSCs	Histologically produced cementum, PDL and alveolar bone
Gronthos et al[44]	DPSCs	Pulp-dentine like tissue complexes lined with odontoblast-like cells
Carinci et al[45]	DPSCs	Bone-like tissues
Sonoyama et al[49]	SCAPs	A typical dentin structure with connective tissues
Battula et al[39]	SCAPs	Bone-/dentin-like mineralized tissues
Miura et al[53]	SHEDs	Dentin-like tissue, but not a dentin-pulp-like complex; not differentiate directly into osteoblasts but only induce new bone formation
Wang et al[55]	SHEDs	Exhibit an enhanced potential to form bone
Park et al[57]/Seo et al[58]	PDLSCs	A typical cementum/PDL-like structure
Morsczeck et al[64]	DFPCs	A structure consists of fibrous or rigid tissue, no dentin, cementum, or bone formation
Handa et al[65]	DFPCs	Cementum-like matrix
Honda et al[66]	DFPCs	Bone

MSCs: Mesenchymal stem cells; SHEDs: Stem cells from human exfoliated deciduous teeth; DPSCs: Dental pulp stem cells; DFPCs: Dental follicle precursor cells; PDLSCs: Periodontal ligament stem cells; SCAPs: Stem cells from apical papilla; BMMSCs: Bone marrow MSCs; PDL: Periodontal ligament.