Human teeth are composed of four different types of tissue: pulp, dentin, enamel, and cementum. Here is a breakdown of each type of tissue:
-
Pulp: The innermost portion of the tooth, consisting of nerves and blood vessels that nourish the tooth. The pulp has two parts: the pulp chamber, which lies in the crown, and the root canal, which is in the root of the tooth.
-
Dentin: A hard yellow substance that surrounds the pulp and makes up most of the tooth. It is as hard as bone and gives teeth their yellowish tint.
-
Enamel: The hardest tissue in the body, covering the dentin and forming the outermost layer of the crown. It lets teeth withstand the pressure of chewing and protects them from harmful changes in temperature from hot and cold foods.
-
Cementum: A layer of cementum covers the outside of the root, under the gum line, and holds the tooth in place within the jawbone.
Enamel is mostly made of calcium phosphate, a rock-hard mineral, and also contains aluminum, copper, nickel, cobalt, iodine, lead, manganese, and selenium. Dentin is slightly yellow in color and consists of 70% inorganic and 30% organic matter. Cementum is a thin layer of bone-like tissue that covers the root of the tooth and attaches it to the jawbone.
