Table 1: Chemical and structural comparison of teeth, bone, and hydroxyapatite (HA).

Composition, wt%EnamelDentineBoneHA

Calcium36.535.134.839.6
Phosphorous17.116.915.218.5
Ca/P ratio1.631.611.711.67
Total inorganic (%)977065100
Total organic (%)1.52025
Water (%)1.51010