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The structure of my teeth

Your teeth are made up of several layers. The whole tooth is composed of the ‘Crown’, outside your gum and the ‘Root’, that sits in the hard jaw bone covered by the soft gum (gingiva).

  • Enamel: The top layer of crown, outside only. Your enamel is mainly made of crystals of a mineral called hydroxyapatite, as well as some proteins and water in the spaces between crystals. Hydroxyapatite is largely made up of calcium (Ca), phosphate (PO4) and hydroxide (OH) along with small amounts of carbonate (CO3), sodium (Na), magnesium (Mg) and potassium (K)
  • Dentin: The layer underneath the enamel (in the crown) or the cementum (in the jaw bone). Dentine is also made of hydroxyapatite but the crystals are smaller and there is more carbonate, water and proteins
  • Pulp: Innermost layer, carries blood vessels and nerve endings, at the tip of the root, these emerge into the jaw bone
  • Cementum: Layer between the dentin and bone, helps anchor the tooth in its socket