The arrangement and shape of teeth are not unreasonably long, it completely matches people's food types. People are omnivores, eating both plants and animals, so the front front teeth are used to chop and bite off food; Dog teeth mainly tear food; Premolars are used to mash food; And grinding teeth can grind food.

The front teeth are very thin, just like a kitchen knife, which is most suitable for cutting off food. In addition, it can also cooperate with the tongue to make the sound of teeth.

Dog teeth are sharp in shape and are specially used for chopping food.

The surface of molars is very rough, just like a millstone, also called molars. Grinding food is very convenient.

The muscles of the chin are very powerful. It pulls the lower forehead toward the upper jaw, so the teeth can bite strongly. Just like a nutcracker, a person's chin can bite walnuts with his teeth.

Children's primary teeth include 8 front teeth, 4 canine teeth and 8 molars.

Adult permanent teeth include 8 incisors, 4 canine teeth and 16 molars. Usually 28, plus 4 wisdom teeth, is 32. But some people have no wisdom teeth.