Two types of dentition are generated in a human's lifetime: the primary dentition, followed by the permanent dentition. Undoubtedly, teeth are essential for speech and mastication in both dentitions, but it is becoming apparent that dental pulp also plays a role in harboring mesenchymal stem cells (MSCs). To date, three kinds of MSCs derived from dental pulp have been established: permanent tooth, primary tooth, and immature apical papilla. The dental pulp from primary teeth is considered a particularly good source of MSCs; it can be obtained from extracted primary teeth, of which humans have 20. The past decade has seen many reports of dental pulp-derived MSCs, and the field is becoming increasingly popular. The present article describes the characterization of dental pulp-derived MSCs from primary teeth. It also discusses future banking activity of primary teeth, because it is known that dental pulp-derived MSCs have similar potential to those derived from bone marrow. Methods with which to optimize the cryopreservation process should therefore be investigated, because banked dental pulp may provide a great resource in future regenerative medicine.