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62 occupied by the pulp is called the pulp chamber. The nerves of the pulp are responsible for pain felt when dentine is drilled or toothache occurs. The outermost layer of the pulp, next to the dentine, is lined with the special cells which form the dentine. Under the microscope fin prolongations of these cells can be seen passing through tubes in the dentine. They run throughout the full thickness of dentine and, by their origin from the pulp, are associated with its repair processes and sensitivity to pain. Supporting structures. Every tooth is inserted 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 fbrous tissue called the periodontal membrane . This acts as a shock absorber and is attached to the cementum of the root and the compact bone lining the socket. The peri‑ odontal membrane contains nerves and blood vessels, but consists mainly of bundles of fbres which pass obliquely from cementum to bone. 8. Using the text give English equivalents for these word combina- tions and sentences. Состоять из; быть скрытым; называться; быть нечувствительным к боли; таким образом; быть скрепленным; быть похожим по струк‑ туре; это такой же дентин, как; она содержит кровеносные сосуды и нервы; пульповая камера; быть ответственным за; рядом с дентином; проходить через; будучи пульпарными по происхождению; быть по‑ крытыми чем-либо; действовать как. 9. Answer the questions. 1. What parts does a tooth have? 2. What is the junction of crown and root called? 3. What is every tooth composed of? 4. What do you know about enamel? 5. What does it consist of? 6. Where does cementum meet enamel? 7. What is cementum? 8. Is dentine sensitive to pain? 9. What does the pulp contain? 10. What is the pulp chamber? 11. What supporting structures can you name?