In the face of extraordinary advances in the prevention, diagnosis, and treatment of human diseases, the inability of most tissues and organs to repair and regenerate after damage is a problem that needs to be solved. Stem cell research is being pursued in the hope of achieving major medical breakthroughs. Scientists are striving to create therapies that rebuild or replace damaged cells with tissues grown from stem cells that will offer hope to people suffering from various ailments. Regeneration of damaged periodontal tissue, bone, pulp, and dentin is a problem that dentists face today. Stem cells present in dental pulp, periodontal ligament, and alveolar bone marrow have the potential to repair and regenerate teeth and periodontal structures. These stem cells can be harvested from dental pulp, periodontal ligament, and/or alveolar bone marrow; expanded; embedded in an appropriate scaffold; and transplanted back into a defect to regenerate bone and tooth structures. These cells have the potential to regenerate dentin, periodontal ligament, and cementum and can also be used to restore bone defects. The kind of scaffold, the source of cells, the type of in vitro culturing, and the type of surgical procedure to be used all require careful consideration. The endeavor is clearly multidisciplinary in nature, and the practicing dental surgeon has a critical role in it. Playing this role in the most effective way requires awareness of the huge potential associated with the use of stem cells in a clinical setting, as well as a proper understanding of the related problems. Schlagwörter: dental pulp stem cells, dentistry, human cementum-derived cells, periodontal ligament stem cells, stem cells from human exfoliated deciduous teeth, stem cells from root apical papilla