Ca10PO46OH2kaavasta

Ca10PO46OH2kaavasta is the textually concatenated form of the chemical formula Ca10(PO4)6(OH)2, widely known as hydroxyapatite. It is the principal inorganic constituent of vertebrate bone mineral and dental enamel, and it belongs to the apatite group of minerals. The idealized formula describes a calcium phosphate compound that can accommodate substitutions and non-stoichiometry in natural and synthetic systems.

Structure and composition: Hydroxyapatite consists of PO4 tetrahedra linked by calcium ions in a hexagonal crystal structure. The structure contains channels along the c-axis that host hydroxide (OH−) groups. In practice, many samples show substitutions in the lattice, giving rise to carbonate-containing, fluoride-containing, or other substituted variants.

Occurrence and significance: In biology, hydroxyapatite is the mineral foundation of bone and tooth apatite nanocrystals, providing rigidity and a reservoir for calcium and phosphate. It also forms the basis for many synthetic biomaterials designed to be biocompatible and bioactive.

Synthesis and properties: Hydroxyapatite can be prepared by wet-chemical precipitation, hydrothermal methods, or solid-state reactions. It is relatively insoluble in neutral to basic environments, with solubility increasing under acidic conditions. The material readily accommodates dopants and can be processed into powders, coatings, or porous scaffolds.

Variants and related materials: Fluorapatite (Ca10(PO4)6F2) replaces OH with fluoride; carbonate-substituted hydroxyapatite is common in bone and teeth. Other substitutions (e.g., chloride, silicon, or magnesium) further modify properties such as solubility and bioactivity.

Applications: Synthetic hydroxyapatite is used for bone graft substitutes, dental coatings, implant coatings, and as a functional biomaterial in areas of regenerative medicine and dentistry.