Recent years have improved our understanding of the plasticity of cell types behind
inducing, building, and maintaining different types of teeth. The latest efforts were
aided by progress in single-cell transcriptomics, which helped to define not only cell
states with mathematical precision but also transitions between them. This includes new
aspects of dental epithelial and mesenchymal stem cell niches and beyond. These recent
efforts revealed continuous and fluid trajectories connecting cell states during dental
development and exposed the natural plasticity of tooth-building progenitors. Such
“developmental” plasticity seems to be employed for organizing stem cell niches in adult
continuously growing teeth. Furthermore, transitions between mature cell types elicited by
trauma might represent a replay of embryonic continuous cell states. Alternatively, they
could constitute transitions that evolvedde novo, not known from the
developmental paradigm. In this review, we discuss and exemplify how dental cell types
exhibit plasticity during dynamic processes such as development, self-renewal, repair, and
dental replacement. Hypothetically, minor plasticity of cell phenotypes and greater
plasticity of transitions between cell subtypes might provide a better response to
lifetime challenges, such as damage or dental loss. This plasticity might be additionally
harnessed by the evolutionary process during the elaboration of dental cell subtypes in
different animal lineages. In turn, the diversification of cell subtypes building teeth
brings a diversity of their shape, structural properties, and functions.