The pulp is a loose connective tissue located in the pulp chamber of the tooth and is surrounded by hard dentin. When the surrounding hard tissues of the tooth are damaged, the pulp may undergo various lesions or even necrosis. When inflammation occurs in the pulp, it is often not easily cured. Currently, root canal treatment is usually performed on teeth with endodontic disease that cannot preserve the living pulp. After root canal treatment, the tooth is only supplied by periodontal tissues, which results in loss of vitality, tooth discoloration, loss of sensory function, brittle tooth tissue, and easy fracture, thus leading to treatment failure. In addition, due to the complexity of the pulp cavity structure and root canal morphology, it is clinically difficult to completely clean the pulp tissue located in the lateral root canal and make the root canal treatment fail. Therefore, it has been a dream of dentists to use tissue engineering techniques to regenerate the pulp tissue and restore the vitality of teeth. At present, there are two methods of tissue engineering for pulp regeneration: one is the application of autologous stem cell composite growth factor and scaffold material transplantation technique, and the other is the application of cell homing technique to regenerate pulp tissue. However, the clinical application of stem cell transplantation technology is hampered by ethical, cell biology and application cost issues such as stem cell source, stem cell tumorigenicity and stem cell culture process in vitro. Cell homing technology involves the use of growth factors to mobilize endogenous cells that are actively adding value in vivo to reach specific tissues, where they can be directed to differentiate under the action of growth factors and regenerate the tissue in situ. A team of researchers at Columbia University School of Dentistry was the first to use both methods to regenerate tissues of the pulp-dentin complex in mice, dogs, and miniature pigs (J Dent Res. 2010, 89(8):842-848) . Recently, his group also achieved in situ regeneration of human dental pulp tissue with mature roots using the cell homing technique, showing that regeneration of human dental pulp tissue by the cell homing technique is no longer a dream (J Endo. 2013,39:929-934).