Light microscopy of a tooth. Plane polarized light micrograph of a unstained section through a molar tooth in the lower jaw. Molar teeth are used for grinding up and chewing food. The crown of this tooth has a cap of enamel (yellow band, top centre). This is the hardest substance in the body, and prevents wearing of the tooth. The tooth is anchored in the gum by its roots (green/blue, running to lower left and right). The pulp cavity (black, upper centre) contains nerves and blood vessels. The pulp is surrounded by dentine (blue/grey) and dentinal tubules (yellow lines) which forms the bulk of the tooth. Dentine is a tissue similar to bone but harder. Magnification x5 when printed at 10 cm.