Adult Dentition

The Permanent Dentition

The human dentition is comprised of two sets of teeth: deciduous (primary) and permanent. The permanent dentition typically emerges following the shedding of the deciduous teeth. This process usually begins around age six and concludes around age twelve or thirteen.

Number and Types of Teeth

A complete set of permanent teeth consists of 32 teeth, arranged in two dental arches (upper and lower). Each arch contains sixteen teeth of four different types. These types are incisors (for cutting), canines (for tearing), premolars (for crushing and grinding), and molars (for grinding).

• Incisors: There are four incisors in each arch (eight total).
• Canines: There are two canines in each arch (four total).
• Premolars (bicuspids): There are four premolars in each arch (eight total).
• Molars: There are six molars in each arch (twelve total), including the wisdom teeth.

Variations in Adult Tooth Count

While 32 is the typical number of permanent teeth, variations are common. Some individuals may be missing one or more teeth due to genetics, developmental issues, or trauma. The presence or absence of wisdom teeth is particularly variable; many individuals require their extraction. Third molars (wisdom teeth) are often impacted and may not erupt.

Dental Anatomy and Physiology

Each tooth comprises various structures, including enamel (the hardest substance in the body), dentin, cementum, and pulp. The pulp contains blood vessels and nerves essential for tooth health. Understanding tooth structure is vital for preventive dentistry and maintaining oral hygiene.