You have thirty- two teeth. Sixteen in the upper jaw and same number in the lower.
You have three kinds of teeth. They have different functions.
In the front are eight sharp incisors. With them you can easily bite through a carrot or apple.
Behind them are the four strong canine teeth. They help you bite off something hard or tough.
And in the back are eight small and twelve large molars. Their job is to grind food.
Your teeth are the hardest part of your body. The layer of white enamel covering them is as hard as ivory. And from ivory they carve billiard balls which can take the most powerful blows.
Beneath the layer of enamel is a softer, but still very hard layer of dentine. This is what the dentist drills when a crack or hole appears in the enamel and it becomes necessary to close the hole with a filling made of hard cement or special metal.
Hidden beneath these two hard layers is soft pulp. It contains the blood vessels which nourish the tooth just as they do the other parts of the body.…
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