by Nicole - Teeth are the hardest substance in the body made up of multiple layers. Teeth are essential for chewing and play an important role in speech. The tooth can be divided into two anatomical parts, the crown and the root.
The Crown - the part of the tooth that is visible within the mouth and is covered with enamel.
The Root - normally not visible as it is embedded in bone. The root makes up 2/3 of the entire tooth and acts as an anchor holding the tooth in place.
Other anatomical part within the tooth structure include:
Enamel - the hard-outer layer of the crown. Enamel is the hardest layer of the tooth but can be damaged by decay if teeth are not properly cared for.
Dentin - forms the bulk of the tooth underlying the enamel. Dentin contains tiny tubes that lead to the pulp. It the protection of the enamel is lost, heat and cold can transmit through these tubes causing pain and sensitivity.
Pulp - the innermost living layer of the tooth. The pulp is soft tissue containing blood vessels and nerve tissue. It can be very painful if tooth decay reaches the pulp.
Cementum - a layer of connective tissue that covers the root of the tooth and binds the tooth firmly to the bone.
The average adult mouth contains 32 teeth but not all of the teeth are shaped the same. Each type of tooth is shaped differently for its specific function.
Incisors - the front 4 teeth on the upper and lower jaws. The incisors are chisel shaped with sharp edges used for cutting food.
Canines - located beside the incisors, 2 on the upper jaw a 2 on the lower jaw. The canines are pointed and used for tearing food.
Premolars - located between the canines and molars, 4 on the upper jaw and 4 on the lower. The premolars have two pointed cusps on their biting surface used for crushing and tearing food.
Molars - located in the back of the mouth, 4 on the upper jaw and 4 on the lower. The molars are larger with multiple cusps on their biting surface used for grinding food.
Wisdom Teeth - also known as the third molar. The wisdom teeth erupt behind the molars around the age of 18. Not everybody has wisdom teeth and often most wisdom teeth have to be extracted to prevent displacement of other teeth.