V Answer the questions.

1. What does dentistry deal with?

2. What are the main parts of a tooth?

3. What is the hardest tissue of a human body?

4. What is inside enamel and cementum?

5. Which is softer – dentine or enamel?

6. What does dentine cover?

7. How do nerves and vessels enter the tooth?

8. How many deciduous teeth does a human have?

9. When does the first milk tooth erupt?

10. When do the first permanent teeth appear?

11. How many permanent teeth are there and what are they namely?

12. What is specific about the third molar?

VI. Change the sentences in the Active Voice into Passive according to the model.

Model: Permanent teeth replace deciduous teeth.

Deciduous teeth are replaced by permanent teeth.

1. This doctor will examine your teeth.

2. Usually dentists treat this disease.

3. Enamel covers the tooth crown.

4. Dentine surrounds the pulp cavity.

5. A saliva ejector evacuates fluids from the mouth.

6. Dentists use cotton rolls to absorb saliva and other fluids.

7. Dr. Davidson used this excavator to remove a temporary filling.

8. Periodontium attaches the tooth to the bone tissue.

9. Dentists use amalgams to restore posterior teeth.

VII. Open the brackets in a correct form (Active or Passive).

1. Many important problems (to discuss) at the conference.

2. The (to recommend) him to use a soft toothbrush.

3. The patient ( to give) the injection of anesthetic.

4. The third or last molar (to call) the wisdom tooth.

5. The carious tooth (to become) the starting point of infection.

6. The tooth (to extract) painlessly.

7. The pain (to disappear) after the proper treatment.

VIII. Read and translate the text using a dictionary.

Teeth and Gums

Six months or so after birth the first deciduous teeth erupt through the gums. A normal child will eventually have twenty baby teeth, ten teeth on each jaw. The deciduous teeth are lost when the permanent ones are ready to emerge. Both sets of teeth are usually present in the gums at birth or shortly afterwards, with the permanent teeth lying under the deciduous ones. By the time the permanent tooth is ready to erupt, the root of the deciduous tooth above it has been completely resorbed by osteoclasts, the six permanent molars in each jaw have no deciduous predecessors. the shedding of deciduous teeth and the appearance of permanent ones follow a fairy consistent pattern. The teeth are held in their sockets by bundles of connective tissue called periodontal ligaments.

IX. Read the text and find Russian equivalents to the underlined phrases. Learn these phrases. Translate the text.

Teeth bite, chew and grind. If you like to eat chocolate, candies and cakes you have a sweet tooth. Teeth are useful for eating and talking and they can also look attractive if they are well-kept. But in the English language they often indicate difficulty or aggression.

Dogs bare their teeth when they want to fight. If a person talks through his teeth or just shows his teeth it’s better to get out of his way quickly. He may be armed to the teeth. If you don’t you may fight tooth and nail to defend yourself. If you can’t bite, never show your teeth! if you are not good at fighting your teeth may start chattering with fear. People’s teeth chatter when they are very cold and frightened or when they have fever.

If you get teeth into something it doesn’t mean that you are feeling dangerous or aggressive. It simply means that you are doing something that involves concentration or effort. You may get your teeth into a good book – and it means you want to read it, not to eat it!