Adult human gingival epithelial cells as a source for whole-tooth bioengineering.

Teeth develop from interactions between embryonic oral epithelium and neural-crest-derived mesenchyme. These cells can be separated into single-cell populations and recombined to form normal teeth, providing a basis for bioengineering new teeth if suitable, non-embryonic cell sources can be identified. We show here that cells can be isolated from adult human gingival tissue that can be expanded in vitro and, when combined with mouse embryonic tooth mesenchyme cells, form teeth. Teeth with developing roots can be produced from this cell combination following transplantation into renal capsules. These bioengineered teeth contain dentin and enamel with ameloblast-like cells and rests of Malassez of human origin.