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ACTIVE VOCABULARY. Read and learn the following words:

Read and learn the following words:

1. crown [kraun] коронка

2. neck[nek] шейка

3. root[rHt] корень

4. visible [`vizibl] видимый

5. hidden[`hidn] спрятанный

6. junction [`GANkSn] место соединения

7. to be called [kLld] называться

8. cover[`kAvq] покрывать

9. hard[hRd] твердый

10. sensitive [`senzitiv] чувствительный

11. unlike[An`laik] в отличие от

12. purely [`pjuqli] чисто

13. insert [in`sWt] вставлять

14. alveolar[`xlvi`oulq] альвеолярный

15. gum [gAm] десна

TEXT

STRUCTURE OF TEETH

Every tooth consists of a crown, a neck and one or more roots. The crown is the part visible in the mouth and the root is the part hidden inside the jaw. The junction of crown and root is called the neck and end of the root is called the apex. Every tooth is composed of enamel, dentine, cementum and pulp.

Enamel is the outer covering of the crown and is the hardest substance in the body.

Cementum is the outer covering of the root and is similar in structure to bone. Cementum meets enamel at the neck of the tooth.

Dentine occupies the interior of the crown and root, and is very sensitive to pain.

Pulp. Unlike enamel, dentine and cementum, the pulp is purely soft tissue. It contains blood vessels and nerves, and occupies the centre of the dentine.

Supporting Structures. Every tooth is insert into the jaw by its root. The part of the jaw containing the teeth is known as the alveolar process and is covered with a soft tissue called gum. The jaw bones consist of a dense outer layer known as compact bone and a softer interior called spongy bone.

A tooth is attached to its socket in the jaw by a soft fibrous tissue called the periodontal membrane.

NOTES

1. Alveolar process – альвеолярный отросток

2. Compact bone – компактное вещество

3. Spongy bone – губчатое вещество






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