**5. Conclusions**

Maintaining tooth function is an important factor in ensuring health and quality of life. Unfortunately, illness, injury, or aging causes many people to lose their teeth and have a poor quality of life. As a result, it is necessary to develop an appropriate method for the restoration of tooth function. Tissue engineering provides an attractive perspective with the potential to regenerate fully functional organs to replace damaged or lost organs. This method required the integration of three key elements: progenitor or stem cells, extracellular matrix scaffold, and morphogens, which induce morphogenetic signals. Therefore, proper stem cell isolation and stable establishment are one of the points that must be achieved to perform regenerative therapy. Within the pulp, it is known that the pulp contains progenitor cells/stem cells, which proliferate and differentiate into various cells. Pulp stem cells can generate a new population of odontoblasts to repair damaged hard tissue. Induction of stem cell proliferation and differentiation is triggered by the release of morphogens from the pulp and periodontal tissue. Such releases occur in response to caries, therapeutic irritation, and injury. We established a cell line from the pulp of GFP transgenic rats, named it TGC, and used it for dentin regeneration. These rat pulp-derived cells were maintained in cultures for more than 80 passages without showing any changes in morphology or ability. Using this TGC and pore diameter 300 μm TCP as a scaffold, odontoblasts could be differentiated to develop polar dentin and create a structure similar to physiological dentin.
