Teeth. Polarised light micrograph of a section through molar teeth in the lower jaw. Molar teeth are used for grinding up and chewing food. The crowns of these teeth have caps of enamel (grey band, upper centre). This is the hardest substance in the body, and prevents wearing of the tooth. The teeth are anchored in the gum by their roots (blue/green). Their pulp cavities (black, centre left and right) contain nerves and blood vessels. This pulp is surrounded by dentine (many colours) which forms the bulk of the tooth. This is a tissue similar to bone but harder.