Researchers from the Institute of Biotechnology at the University of Helsinki and their collaborators from Berlin and Kyoto have now shown that continuous tooth generation can be induced in mammals. The research results were published in `Proceedings of the National Academy of Sciences,` (PNAS). The researchers activated the Wnt signaling pathway in mouse tissue; this signaling pathway is one of those used for cell communication and plays an important role in embryonic development. As a result of stimulating this particular signaling pathway, one mouse molar developed dozens of new teeth with normal dentin, tooth enamel and developing roots. The crowns were, however, simple and cone-shaped, unlike the typically more complex multiple cusps of mouse molars.