英语流利说懂你英语Level4 Unit1 Part3 Vocabulary-Dental Problems

A dental cavity is a hole in the tooth.

A cavity is caused by bacteria in the mouth.

Brushing your teeth frequently and regularly can help prevent cavities.

A cracked tooth can be caused by biting down on something hard.

Dentists treat a cracked tooth by covering it with a crown.

A dental X-ray is a picture of your teeth and gums.

An X-ray shows what can't be seen on the surface of the teeth and gums.

Braces are used by dentists to straighten teeth over a period of years.

Though braces are usually for children, they can also be used for adults with crooked teeth.

To extract a tooth means to remove it from the mouth.

Dentists have to pull hard to extract a tooth.

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