Nano Hydroxyapatite Particle Technology and Mineral Structure The APAGARD nano hydroxyapatite formula employs medical-grade crystalline calcium phosphate fragments [Ca10(PO4)6(OH)2] synthesized at nanometer scale with average diameter of 50-100 nanometers, matching the dimensional characteristics of all-natural enamel crystallite framework. This fragment size allows infiltration into enamel micropores and subsurface demineralized zones measuring 1-10 micrometers deepness, promoting …