Cellular and Molecular Mechanisms Guiding the Development and Repair of the Dentin–Pulp Complex

Odontogenesis is a complex process, which requires reciprocal signaling and tight coordination between the oral epithelium and the adjacent neural crest-derived ectomesenchyme. Both the enamel and the dentin-pulp complex of the mature tooth are derived from these two germ layers through a series of intermediate phases. This chapter will focus on the dentin-pulp complex, which is derived from the ectomesenchyme. Odontoblasts were initially perceived as dentin-producing cells and are now recognized also as sensory cells, which participate in defense-related inflammatory processes. Upon injury or bacterial infection in a fully developed tooth, dental pulp stem cells can be induced to differentiate into dentin-producing odontoblasts, as in reactionary dentin. A better understanding of the molecular and cellular mechanisms driving this process is underway to fully exploit the endogenous potential of the dentino-pulpal complex in restorative dentistry. This chapter will provide a synopsis of the development of the dentin-pulp complex, highlighting its importance as well as key features of the ectomesenchyme in development and in maintaining healthy teeth. Finally, some recent advances and new insights into the biology of the dentin-pulp complex and how they may be exploited to improve dental treatments are highlighted.