cementoblast

Cementoblasts are specialized mesenchymal cells that synthesize cementum, the mineralized tissue that covers the tooth root and anchors the periodontal ligament. They originate from the dental follicle (dental sac) mesenchyme and differentiate on the root surface during root formation, in association with the periodontal ligament.

Cementoblasts secrete the organic matrix of cementum, rich in type I collagen and non-collagenous proteins such as cementum-derived proteins. As the matrix matures and mineralizes, cementoblasts remain on the surface to form cementum or become embedded in the matrix as cementocytes, giving rise to cellular cementum. Depending on location along the root, cementum may be acellular (lacking embedded cells) or cellular (containing cementocytes in lacunae). The deposited cementum provides the attachment for periodontal ligament fibers (Sharpey’s fibers) that anchor the tooth to the surrounding bone.

Cementum is avascular and nourished by diffusion from the periodontal ligament and surrounding tissues. Its mineral content and growth rate are lower than those of bone, and cementoblast activity is tightly coordinated with tooth eruption and periodontal remodeling.

Clinical relevance includes hypercementosis, an excessive formation of cementum often associated with occlusal stress or systemic conditions; cementoblastoma is a rare odontogenic tumor composed of cementum-like tissue. Abnormal cementoblast function or cementogenesis defects can contribute to periodontal attachment problems.