Dentin hydroxyapatite

Dentin hydroxyapatite refers to the crystalline mineral phase—primarily calcium hydroxyapatite (\(\mathrm{Ca_{10}(PO_4)_6(OH)_2}\))—that constitutes the majority of the inorganic matrix in dentin, the hard tissue beneath enamel in teeth[1][5][7]. Hydroxyapatite provides rigidity and hardness by embedding in the collagen-rich organic matrix, but, compared to enamel, dentin hydroxyapatite crystals are smaller, resulting in a tissue that is mineral-rich, yet somewhat more flexible and permeable than enamel[1][7]. Hydroxyapatite in dentin plays a vital structural role, contributing to tooth strength and serving as the primary target for demineralization-remineralization dynamics during caries development and repair. It is not a biological “target” in the sense of a receptor, enzyme, or transporter, but rather a critical inorganic mineral phase found within a tissue[3][5][7]. Hydroxyapatite in dentin can interact with therapeutic materials in dentistry, such as in remineralizing toothpastes and restorative agents that deposit new hydroxyapatite crystals for structural repair and sensitivity reduction[2][6][10]. Its integrity is essential for dental health, and its loss or degradation is implicated in caries, hypersensitivity, and erosion. However, it is not a druggable protein or receptor but an essential material substrate within teeth. Note: “Dentin hydroxyapatite” is not a canonical drug target or receptor but rather describes the major mineral constituent of dentin[1][3][7]. This entry is thus “incorrect” per target databases that list only proteins, receptors, ion channels, etc.

Other names

Hydroxyapatite in dentindental hydroxyapatitedentin mineral

Remineralization (recrystallization of hydroxyapatite onto dentin) Tubule occlusion (blocking dentinal tubules to reduce sensitivity)