Epithelial cell rests of Malassez
In dentistry, the epithelial cell rests of Malassez (ERM) or epithelial rests of Malassez (pax epithelialis pediodontii) are part of the periodontal ligament cells around a tooth. They are discrete clusters of residual cells from Hertwig's epithelial root sheath (HERS) that didn't completely disappear. It is considered that these cell rests proliferate to form epithelial lining of various odontogenic cysts such as radicular cyst under the influence of various stimuli. They are named after Louis-Charles Malassez (1842–1909) who described them. Some rests become calcified in the periodontal ligament (cementicles)
ERM plays a role in cementum repair and regeneration. The stem cells in ERM can undergo an epithelial–mesenchymal transition and differentiate into diverse types of cells of mesodermal and ectodermal origin like bone, fat, cartilage and neuron-like cells.
- Rincon JC, Young WG, Bartold PM (2006). "The epithelial cell rests of Malassez--a role in periodontal regeneration?". J Periodontal Res. 41 (4): 245–52. doi:10.1111/j.1600-0765.2006.00880.x. PMID 16827716.
- Xiong J, Gronthos S, Bartold PM (2013). "Role of the epithelial cell rests of Malassez in the development, maintenance and regeneration of periodontal ligament tissues.". Periodontol 2000. 63 (1): 217–33. doi:10.1111/prd.12023. PMID 23931062.