Page 52 - Science class 4

Canines

There are four canine teeth in all, two Keeping Update
in the upper jaw and two in the lower

one. We have one canine on both Four molars grow later and are

sides of the incisors. Canines are called wisdom teeth.
sharp and are used for tearing food.

In flesh-eating animals, these canines are bigger and very sharp so that

tearing flesh is easier.

Premolars

There are eight premolars in all, four in each
jaw. These are broad teeth, next to the canines.

Premolars help to crack food and chew it.

Molars

There are twelve molars in all. Each jaw has six
molars present behind the premolars. They are

bigger, flatter and broader teeth, with a broader
upper surface to chew and grind the food well. Premolar Molar

Plant-eating animals have well-developed premolars and molars, since they
need to chew and grind their food a lot. Out of the twelve molars, eight grow

first, two on each side of the premolars. Four more molars grow later.

PARTS OF A TOOTH
Though, we have three parts of a tooth : the crown , the neck and the root ,

they have the same basic structure.

When we smile we can see our teeth. But, what we see is not our entire tooth.
It is actually only a part that is visible to us.

Enamel The crown is the part we see, while the
Crown root is the part inside the gums . The
Dentine
Pulp gums hold the teeth in their places. The
region between the crown and the root is

Nerves called the neck.
& Veins
The hard, white part on the outside of a
Gum
Gum
Gum
Root tooth is called enamel . It protects the
teeth from the wear and tear of chewing.
Parts of a Tooth
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