Provided is a novel and creative dental tissue regeneration method for regenerating dental tissue after pulpectomy or the enlargement and cleaning of an infected root canal. After pulpectomy or the enlargement and cleaning of an infected root canal, a root canal filler (200) having an extracellular matrix (210) containing the cells (220) enriched for dental pulp stem cells, is inserted into the apical side of the root canal of a target tooth (100). The cells including dental pulp stem cells include at least one of the following: dental pulp SP cells, CD31-negative and CD146-negative cells, CD24-positive cells, CD105-positive cells, and CD150-positive cells. For instance, dental pulp SP cells are CD31− and CD146− negative. Even if pulpitis due to deep caries occurs, appropriate dental pulp regeneration and recovery of dental pulp function are possible.
