Abstract: Objective To regenerate dentin-pulp complex by tissue engineering with human stem cells from apical papilla cells
(SCAP) as the seed cells. Methods SCAP was separated from from normal human impacted third molars with immature roots
by outgrowth culture. The cells were then cultured in the differentiation medium for 3 weeks or in normal medium for 60
days, and analyzed for mineralization potential by Alizarin red staining. The osteo/odontogenic markers including alkaline
phosphatase (ALP), bone sialoprotein (BSP), osteocalcin (OC) and dentin sialoprotein (DSP) were investigated by
immunofluorescence staining and reverse transcription-polymerase chain reaction. The co-cultured mixture of SCAP and HA/
TCP, or HA/TCP alone was implanted subcutaneously on the back of nude mice for 8 weeks, and the implants were collected
and examined by HE and immunohistochemical staining. Results Round alizarin red-positive nodules formed in the isolated
cells after cell culture in the differentiation medium for 3 weeks or in normal medium for 60 days with positive staining for
osteo/odontogenic markers. SCAP with HA/TCP could regenerate pulp-dentin complex-like tissue in nude mice. The cells near
the dentin-like tissue were positive for DSP. No mineral tissue was found in mice receiving HA/TCP implantation. Conclusion
SCAP may serve as a promising seed cell for dentin-pulp complex tissue engineering.