The anatomy of a tooth

Crown: upper and visible from the tooth.
 
 Email: white, hard and shiny covering the tooth. Enamel protects the dentin at the height of the dental crown.
 
 Dentin: tissue beneath the hard enamel that forms the bulk of the tooth and surrounding pulp cavity. The dentin has a yellowish color. It is the cause of the yellowish color of teeth, especially when the enamel layer is thin.
 
 Gingival sulcus: meeting point between the tooth and gum. This is where they accumulate plaque and tartar.
 
 Dental pulp: soft tissue in the heart of the tooth which contains many nerves and blood vessels. There is pain when cavities reached the dental pulp.
 
 Racine: Root portion of the tooth included in the tooth socket. The roots are covered by cement, and then by ligaments alveolodentaires. They represent about two thirds the height of the tooth and ensure its continuation. The cement is more porous than enamel which is the cause of dental hypersensitivity in gums.