The Probert Encyclopaedia of Medicine

CEMENTUM

The cementum (substantia ossea) is the third hard tissue of the tooth. Periodically secreted by specialized cells (cementoblasts) in the periodontal membrane, the cementum is a coarse material which binds and anchors the tooth to the periodontal ligament. The cementum is composed of about 50% organic tissue, with the rest being water and inorganic (mostly calcium) salts. If the periodontal membrane is damaged, the cementum may be reabsorbed back into the membrane.
Research Cementum