Human teeth are hardened, bone-like structures that extend from your jaws and gums and allow you to perform various tasks related to eating, biting and tearing. These structures, which begin to form before you are born, help make everyday survival possible, but you must take proper care of them or they may decay over time.
Tooth Components
Each of your teeth is protected by a hardened outer layer called enamel, according to the Nemours Foundation. Beneath this layer lies the main portion of tooth material, called dentin. This dentin protects the next layer, called the pulp, which contains the tooth’s blood supply and nerve ending. The pulp of each tooth extends down below your gum to the tooth’s root. This root, which secures each tooth to your jaw, is made from a material called cementum.
Tooth Types
You have different types of teeth that are designed for different uses, the Nemours Foundation explains. Your top and bottom front teeth, called incisors, allow you to chop and cut your food. The pointed teeth on either side of your incisors, called canine teeth, allow you to tear your food. Your four top and bottom premolars, which sit next to your canines, allow you to grind and crush your food. Your four top and bottom molars further grind food that is shoved to the back of your mouth by your tongue. An additional set of top and bottom molars, called wisdom teeth, also evolved to grind food, although you typically no longer need them for this task.
Baby Teeth
The core structures of your teeth begin forming after roughly six weeks of fetal development, according to Children’s Hospital Boston. After three or four months, protective enamel coats each tooth’s exterior. Following birth, these teeth remain below the gum line for anywhere from six months to a year, after which a single tooth typically appears, the Nemours Foundation reports. This initial tooth is then followed by others, until a full set of 20 primary or baby teeth emerge from the gums by approximately age three.
Permanent Teeth
You begin losing your baby teeth by age five or six, the Nemours Foundation notes. This process occurs as your permanent teeth form and force your baby teeth from your gum line. Typically, children gain their full set of permanent teeth by age 12 or 13. Wisdom teeth, which emerge in late adolescence or early adulthood, get their nickname from their relatively late arrival in your mouth.
Tooth Care
Without proper care, the enamel surfaces of your teeth may erode over time, leading to tooth decay and the formation of cavities. The American Dental Association lists methods of preventing tooth decay that include brushing your teeth twice daily with fluoride toothpaste, eating a balanced diet and limiting snacks between meals, using floss or an interdental cleaner to clean between your teeth and seeing a dentist regularly for oral examination and teeth cleaning.
