The cementum is the part of the periodontium that attaches the teeth to the alveolar bone by anchoring the periodontal ligament.

[5] The cementum joins the enamel to form the cementoenamel junction (CEJ), which is referred to as the cervical line.

The CEJ may exhibit all of these interfaces in an individual's oral cavity, and there is even considerable variation when one tooth is traced circumferentially.

[3] The dentinocemental junction (DCJ) is a relatively smooth area in the permanent tooth, and attachment of cementum to the dentin is firm but not understood completely.

[8] The different categories of cementum are based on the presence or absence of cementocytes, as well as whether the collagen fibres are extrinsic or intrinsic.

[17] Cementum is avascular, receiving its nutrition through its own imbedded cells from the surrounding vascular periodontal ligament.

Cementum on the root ends surrounds the apical foramen and may extend slightly onto the inner wall of the pulp canal.

These cementoblasts develop from undifferentiated mesenchymal cells in the connective tissue of the dental follicle or sac.

[8] Unlike ameloblasts and odontoblasts, which leave no cellular bodies in their secreted products, during the later steps within the stage of apposition, many of the cementoblasts become entrapped by the cementum they produce, becoming cementocytes.

[11] A 2010 archeological study has found that cementum has five times the amount of mitochondrial DNA compared to dentin, which is commonly sampled.