Uses of teeth

1. Teeth help in chewing of food. 2. Teeth help in phonation 3. They offer support to the facial tissues and therefore are important in facial appearance. 4. Presence of teeth helps maintain the health of the jaws.

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Milk teeth and permanent teeth

Humans exhibit two sets of teeth. At birth no teeth are visible in the oral cavity. Soon the primary or the milk teeth appear in the oral cavity. These primary teeth are later shed off and are replaced by the permanent teeth.

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Parts of a tooth

The human tooth has two primary components : the crown and root. The crown is the portion of the tooth that projects above the gums while the root is that portion that anchors the tooth to the bone. The teeth are composed of 4 tissues. The enamel covers the crown of the teeth and is the hardest known substance in the human body. This extreme hardness is necessary to survive the powerful forces exerted on the tooth surface during chewing. Inner to the enamel is the dentin forming the bulk of the tooth. Cementum covers the root portion of the tooth and gives attachment to certain fibers called periodontal ligament that help the tooth attach to the jaws. The pulp is the innermost part of the tooth containing the nerves, blood vessels and other cells. The pulp is the vital area of the tooth. Gums are soft tissues that cover the tooth like a collar.

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Arrangement of teeth

Teeth are embeded in the upper and lower jaw bones. They are arranged in each jaw in the form of an arch. When the person closes his mouth the teeth of the upper and lower arches interdigit with one another. This in scientific words is called occlusion.

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Types of teeth

Humans have teeth of four distinct type each having a typical appearance and performing a certain function. The incisors are the front teeth that are so called because they help to incise food. They are flat blade like teeth . There are 2 incisors in each quadrant of the jaw. Canines are teeth that are present at the corners of the mouth. They are pointed teeth that help in shearing food. Next to the canines are 2 premolars which have broader grinding surfaces and therefore help in chewing and grinding of food. The molars are large back teeth having a large grinding surface used primarily to grind food.