Teeth

Teeth are hard structures in the mouth of many vertebrate animals, particularly prominent in humans. Their main function is to break down, crush, and prepare food for digestion. Teeth also play a role in speech and facial appearance.

Teeth are among the hardest tissues in the human body, based on their outer layer known as enamel, which is rich in minerals. Teeth are not bone, despite their similar appearance in color; their structure differs from that of bone.

Structure

A tooth is divided into the crown, the visible part in the mouth, and the root, which lies within the jawbone. The outermost layer of the crown is enamel. Beneath this lies dentin, a softer, porous layer that transmits sensation. At the center is the pulp chamber, which contains blood vessels and nerves. The root is covered by cementum and is attached to the jawbone by small fibers called the periodontal ligament.

Types of teeth

Humans have four types of teeth: incisors, which cut food; canines, which tear; premolars and molars, which grind. Each type has a shape suited to its function.

Development

Humans have two sets of teeth. The first consists of primary teeth in children, which begin to emerge in the first months of life. These are later replaced by permanent teeth, which begin to appear around school age. The final molars, commonly called wisdom teeth, may emerge later or not at all.

Oral health

Bacteria in the mouth convert sugars into acids that erode enamel, leading to cavities. Plaque buildup on teeth can also cause gum disease. Regular cleaning, water intake, and dental visits reduce these problems. Fluoride is added to dental treatments to strengthen enamel.