Osteogenic mesenchymal stem cells/progenitors in the periodontium.

Periodontitis is the major cause of tooth loss in adults and is mainly characterized by alveolar bone destruction. Elucidating the mesenchymal stem cell (MSC)/progenitor populations of alveolar bone formation will provide valuable insights into regenerative approaches to clinical practice, such as endogenous regeneration and stem cell-based tissue engineering therapies. Classically, MSCs residing in the bone marrow, periosteum, periodontal ligament (PDL) and even the gingiva are considered to be osteogenic progenitors. Furthermore, the contributions of MSCs expressing specific markers, including Gli1, Axin2, PTHrP, LepR and α-SMA, to alveolar bone formation have been studied using cell lineage tracing and gene knockout models. In this review, we describe the MSCs/progenitors of alveolar bone and the biological properties of different subpopulations of MSCs involved in alveolar bone development, remodeling, injury repair and regeneration.