Molar (tooth)

Large chewing tooth at the back of the mouth

Anatomy

A molar is a type of tooth located at the back of the mouth in most mammals. Molars are large, flat teeth that are primarily used for grinding food during mastication (chewing). Humans typically have twelve molars, with three on each side of the upper and lower jaws. These include the first, second, and third molars, with the third molars commonly known as wisdom teeth.

Anatomy

Molars have a broad and flat surface with multiple cusps to aid in the grinding of food. The structure of a molar includes the crown, which is the visible part above the gum line, and the root, which anchors the tooth into the jawbone. The crown is covered with enamel, the hardest substance in the human body, while the root is covered with cementum.

Types of Molars

In humans, there are three types of molars:

• First molars – These are the first permanent molars to erupt, usually around the age of six.
• Second molars – These typically erupt around the age of twelve.
• Third molars – Also known as wisdom teeth, these usually erupt in late adolescence or early adulthood.

Function

The primary function of molars is to grind food into smaller pieces to facilitate swallowing and digestion. The large surface area and multiple cusps of molars make them well-suited for this task. Molars work in conjunction with the premolars, which are located just in front of them, to efficiently process food.

Development

Molars develop from the dental lamina during the embryonic stage. The process of molar development involves the formation of the dental papilla, which gives rise to the dentin and pulp of the tooth, and the dental follicle, which forms the supporting structures of the tooth, including the periodontal ligament.

Clinical Significance

Molars are prone to dental caries (cavities) due to their complex surface and the difficulty of cleaning them thoroughly. They can also be affected by periodontal disease, which can lead to the loss of the supporting structures of the tooth. Impacted wisdom teeth are a common issue, where the third molars do not have enough space to erupt properly, leading to pain and potential infection.

See Also

• Tooth development
• Dental anatomy
• Premolar
• Wisdom tooth
• Periodontal disease