A Chemically Defined Culture for Tooth Reconstitution

The study introduces a chemically defined culture system for tooth reconstitution, enabling the formation of tooth-like structures, or toothoids, from embryonic dental cells. This system supports the sequential induction of stage-specific markers and the development of critical dental lineages, such as odontoblasts and ameloblasts, without resetting the developmental clock. Key findings include the necessity of sustained Activin A and SHH activator stimulation, and the importance of BMP/TGF-β signaling for enamel secretion and maturation. While the culture system successfully reconstitutes molar and incisor toothoids, it cannot induce root development in vitro, indicating a need for additional microenvironmental signals. The study suggests that combining toothoids with neural crest cells may enhance in vitro tooth development, providing a foundation for future tooth bioengineering efforts.