Dental Mesenchymal Stem Cells in Inflamed Microenvironment: Potentials and Challenges for Regeneration.

Adult dental mesenchymal stem cells (DMSCs) are multi-potent stem cells that are involved in dental tissue repair and regeneration. DMSCs are able to differentiate into multiple lineages, including odontogenic, osteogenic, neurogenic, adipogenic, chondrogenic, hepatogenic lineages and insulinproducing cells. However, the DMSCs from functioning, impacted or exfoliated teeth may not be available when needed. Recently, DMSCs have been found in pulpal, periapical and periodontal tissue with inflammation from deciduous and immature/mature permanent teeth. DMSCs from inflamed tissue (iDMSCs) possess typical stem cell characteristics while they showing varied properties. Whether iDMSCs are comparable to healthy DMSCs and can be used for regeneration are not clear. Studies on the impact of infection/inflammation in the local microenvironment on DMSCs are widely conducted to investigate the specific influences and underlying mechanisms in vitro and in vivo. In this review, we introduced the discovery of iDMSCs from different sources, and also discussed the influence of dental inflammation and associated immune responses, particularly the effect from lipopolysaccharide (LPS) stimulation, on local DMSCs. In addition, the effects of dental procedures and materials on DMSCs are discussed.