Stem cells are undifferentiated cells that can differentiate into specialized cell types and come from embryos and adult tissue. They have the potential for cell renewal and can differentiate into different cell lineages. Stem cells could potentially be used to grow new tissues and organs through tissue engineering, gene therapy, and implantology applications to repair damage from burns, periodontal disease, and other conditions. The mechanisms of oral tissue repair depend on the specific type of tissue, with enamel unable to repair but dentin capable of repair through scar tissue formation, and oral mucosa often healing without scars.