Loss of pulp due to caries and pulpitis leads to loss of teeth and reduced quality of life. Thus, there is an unmet need for regeneration of pulp. A promising approach is stem cell therapy. Autologous pulp stem/progenitor (CD105(+)) cells were transplanted into a root canal with stromal cell-derived factor-1 (SDF-1) after pulpectomy in mature teeth with complete apical closure in dogs. The root canal was successfully filled with regenerated pulp including nerves and vasculature by day 14, followed by new dentin formation along the dentinal wall. The newly regenerated tissue was significantly larger in the transplantation of pulp CD105(+) cells with SDF-1 compared with those of adipose CD105(+) cells with SDF-1 or unfractionated total pulp cells with SDF-1. The pulp CD105(+) cells highly expressed angiogenic/neurotrophic factors compared with other cells and localized in the vicinity of newly formed capillaries after transplantation, demonstrating its potent trophic effects on neovascularization. Two-dimensional electrophoretic analyses and real-time reverse transcription-polymerase chain reaction analyses demonstrated that the qualitative and quantitative protein and mRNA expression patterns of the regenerated pulp were similar to those of normal pulp. Thus, this novel stem cell therapy is the first demonstration of complete pulp regeneration, implying novel treatment to preserve and save teeth.