Last reviewed 01/2018

Hydroxyapatite is the inorganic mineral component of bone. It has the chemical formula: 3Ca3(PO4)2Ca(OH)2. With type I collagen and mucopolysaccharide, it forms the bone matrix.

Osteoblast cells are involved in the deposition of hydroxyapatite. Osteoclast cells carry out the reverse process. Control of deposition is multifactorial and includes:

  • adequate ion concentration, particularly calcium and phosphate
  • presence or absence of pyrophosphate molecule inhibition
  • modulation of osteoblasts and osteoclasts by hormonal influences e.g. vitamin D and calcitonin