A cementoblast is a biological cell that forms from the follicular cells around the root of a tooth, and whose biological function is cementogenesis, which is the formation of cementum (hard tissue that covers the tooth root).
The mechanism of differentiation of the cementoblasts is controversial but circumstantial evidence suggests that an epithelium or epithelial component may cause dental sac cells to differentiate into cementoblasts, characterised by an increase in length.
[2] Martha Somerman and her laboratory played a key role in identifying and characterizing cementoblasts, the cells responsible for forming cementum, a vital mineralized tissue covering tooth roots.
[6] The progenitor cells also found in the PDL region contribute to the mineralization of the tissue.
However, a layer of cementoblasts is always present along the outer covering of the PDL; these cells can then produce cementum if the tooth is injured (see hypercementosis).