Though teeth have been grown in mice before, scientists revealed in the Proceedings of the National Academy of Sciences success at growing a ‘fully functional’ tooth from stem cells in mice.

The article states:

“Here, we report a successful fully functioning tooth replacement in an adult mouse achieved through the transplantation of bioengineered tooth germ into the alveolar bone in the lost tooth region. We propose this technology as a model for future organ replacement therapies. The bioengineered tooth, which was erupted and occluded, had the correct tooth structure, hardness of mineralized tissues for mastication, and response to noxious stimulations such as mechanical stress and pain in cooperation with other oral and maxillofacial tissues. This study represents a substantial advance and emphasizes the potential for bioengineered organ replacement in future regenerative therapies.”

The process is described in a paper titled “The development of a bioengineered organ germ method” in the journal Nature Methods by researchers with the Department of Biological Science and Technology at the Tokyo University of Science.

“The process works by taking epithelial and mesenchymal tissue from an existing tooth. Both types of tissues are then refined to become stem cells, which have the ability to become connective tissue, blood vessels, and the outer surfaces of the tooth. The refinement process takes 2 days for enough cells to be grown.

The epithelial and mesenchymal stem cells are then allowed to grow until a high cell density is achieved, which forces them to become the correct type of teeth. After two weeks, the cells have become fully grown teeth, and can be implanted into a mouse.

Transplantation is then achieved by cutting a small hole in the jaw where the tooth is to be implanted. The tooth is then implanted and the area thoroughly cleaned. Two more weeks after transplantation, the teeth are seated in the jaw, and have all the qualities of an original tooth, including: blood vessels, periodontal ligaments, alveolar bone, root, enamel and dental pulp.”

Dr Kazuhisa Nakao said: “Every bio- engineered tooth erupted through the gum and had every tooth component such as dentine, enamel, pulp, blood vessels, nerve fibers, crown and root.”