DentinMatrix

Dentin matrix refers to the organic extracellular component of dentin, secreted by odontoblasts during dentinogenesis. It consists primarily of type I collagen, which forms a fibrous scaffold, and non-collagenous matrix proteins that regulate mineralization and signaling. The organic matrix is laid down as predentin and subsequently mineralizes to become dentin.

Key components include collagen type I; dentin sialoprotein and dentin phosphoprotein (derived from DSPP); dentin matrix protein 1 (DMP1); osteopontin; and small proteoglycans such as decorin and biglycan. These components interact to modulate nucleation and growth of hydroxyapatite crystals and to influence dentin tubule organization.

Function includes providing scaffold for mineral deposition, guiding dentinogenesis, and participating in signaling that maintains odontoblast phenotype.

Formation and maturation: odontoblasts synthesize predentin, which is rich in collagen and non-collagenous proteins; mineralization occurs via deposition of hydroxyapatite within and around the organic matrix; tubule patterning is influenced by matrix composition.

Clinical relevance: defects in dentin matrix proteins, particularly DSPP mutations, cause dentinogenesis imperfecta and dentin dysplasia; alterations can affect mineralization and dentin toughness; the dentin matrix is a focus in regenerative dentistry and biomaterials research.