A tooth is a hard, white structure located in the mouth. Teeth form an important part of the dentition. Human teeth are adapted for eating both meat and plants, as humans are omnivores.
An adult human normally has 32 teeth and molars (16 in the upper jaw and 16 in the lower jaw). A child with a primary dentition has 20 teeth. In humans, the dentition changes only once.
Functions of Teeth
Teeth serve several functions:
- In Eating; Chewing, Biting and Grinding Food.
- In Speech; Articulation of Certain Sounds Such as "T" and "S".
- In Appearance; a Healthy Set of Teeth and White Teeth Are Considered More Attractive.
- In Playing Musical Instruments; Wind Instruments Such as the Saxophone and Clarinet.
- In Displaying Emotions; Teeth Are Shown When Smiling.
Rules for Teeth in Passport Photos
According to the passport photo requirements, teeth should not be visible in the photo.
A neutral facial expression is required to ensure optimal recognizability. An open mouth can be distracting and is therefore not allowed.