As permanent teeth develop beneath the gum, the roots of the baby teeth are re-absorbed causing them to loosen and fall out. Baby teeth begin to fall out between 6-12 years of age and permanent teeth fill in as replacements. There are 32 teeth in a permanent set but sometimes the last molars or wisdom teeth are absent or must be removed. Each tooth has two sections, the crown and the root. The crown is the region above the gum line and is covered in hard enamel.
Cells producing enamel degenerate after the tooth has broken through the gum.
Therefore, any cracks or breaks in the tooth surface have to be artificially repaired with fillings. The root of the tooth is below the gum line and anchors the tooth in the jaw. The molars in the top of the mouth have three roots for more secure anchoring in the jawbone. Skin is an architectural marvel that receives little respect from its users. Without your skin, your insides would spill right out.