Dentin is a major part of the tooth. It’s color ranging from creamy white to yellow greatly contributes to the resulting color of the tooth. This calcified part of the tooth extends from the crown to the root of the tooth. Enamel covers the dentin on the crown while cementum covers the dentin on the root.
Dentin serves as protection for the pulp which has the nerves and the blood vessels. Dentin is made up of dentinal tubules which are actually microscopic channels containing fluid and cellular structures making it porous and susceptible to infection. The enamel on the crown helps protect this vital part of the tooth. When the enamel is damaged, the dentin is exposed and this will result in sensitive teeth. Sensitive teeth is painful when exposed to sudden changes in temperature, too much acids, sweets or certain harsh chemicals. It is important to take care of the enamel and dentin by regular brushing, mouthwash gargling, dental flossing and regular dental check up to ward off infection. If infection managed to penetrate the enamel and reach the dentin, it can cause rotting and can be very painful and expensive to treat. This can also lead to secondary infections and other complications like septicemia.
The ivory from elephants is solid dentin. It is not as hard as enamel and can be used in piano keys, billiard balls, jewelry, carved art objects and other things. In some herbivore mammals like horses, deer and elephants where the crown is made up of alternating dentin and enamel, regular chewing cause some ridges in the tooth and this helps to tear down plant fibers as they masticate.