Table 1.
Comparative compositions and structural parameters of inorganic phases of enamel, dentin, bone, and hydroxyapatite.
| Composition | Enamel | Dentin | Bone | Hidroxyapatite |
|---|---|---|---|---|
| Calcium (wt. %) | 36.5 | 35.1 | 34.8 | 39.6 |
| Phosphorus (wt. %) | 17.7 | 16.9 | 15.2 | 18.5 |
| Ca/P (molar ratio) | 1.63 | 1.61 | 1.71 | 1.67 |
| Carbonate (CO32−) (wt. %) | 3.5 | 5.6 | 7.4 | - |
| Sodium (wt. %) | 0.5 | 0.6 | 0.9 | - |
| Magnesium (wt. %) | 0.44 | 1.23 | 0.72 | - |
| Potassium (wt. %) | 0.08 | 0.05 | 0.03 | - |
| Fluoride (wt. %) | 0.01 | 0.06 | 0.03 | - |
| Chloride (wt. %) | 0.30 | 0.01 | 0.13 | - |
| Pyrophosphate (P2O74−) (wt. %) | 0.022 | 0.1 | 0.07 | - |
| Totale inorganic (wt. %) | 97 | 70 | 65 | 100 |
| Total organic (wt. %) | 1.5 | 20 | 25 | - |
| Water | 1.5 | 10 | 10 | - |
| a axis (nm) | 0.9441 | 0.9421 | 0.941 | 0.9430 |
| c axis (nm) | 0.6880 | 0.6887 | 0.689 | 0.6891 |
| Cristallinity Index (HA = 100) | 70–75 | 33–37 | 33–37 | 100 |
| Cristalline size (nm) | 100 × 90 × 30 | 35 × 25 × 4 | 50 × 25 × 4 | 200–600 |
| Ignition products (800 °C) | β-TCP + HA | β-TCP + HA | HA + CaO | HA |
| Elasticity modulus (GPa) | 80 | 15 | 0.34–13.8 | 10 |
| Compressive strenght (MPa) | 10 | 100 | 150 | 100 |