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Text 8. How fluoride works

    1. Fluoride is a natural element that can be found in many things, like the water we drink and the food we eat. Decades ago, scientists began to notice that children who lived in places where fluoride occurred naturally in the water, had fewer dental cavities.

    2. Fluoride which is absorbed by your body is used by the cells that build your teeth to make stronger enamel. Topical fluoride - fluoride that is applied to the outside of the enamel - makes the crystals that form enamel more durable. Tooth enamel crystals that have fluoride are much more resistant to acid. They are less likely to breakdown and cause the tooth surface to become porous.

    3. If your dentist recommends a fluoride treatment during your next dental visit, you'll be receiving topical protection. The fluoride your dentist puts in your mouth will help make the crystals in your tooth enamel stronger. Always use a toothpaste with fluoride.

    4. Brushing your teeth is one of the most effective ways of keeping your teeth healthy Contrary to what you might think, a gentle brushing with a soft-bristle toothbrush is just as effective (and less damaging!) than a vigorous scrubbing with a stiff-bristle toothbrush

Write down the letter of the paragraph which

mentions scientists’ discovery of the connection between fluoride and dental cavities

1 _____

describes the effect fluoride produces on enamel

2 _____

advises what toothbrush to use

3 _____

tells about location of fluoride

4 _____

describes fluoride treatment your dentist uses

5 _____

Decide whether the statements are true or false and put (T) or (F) next to the statement

Children who don’t get enough fluoride might have more dental cavities.

6 _____

Fluoride influences the crystals of the enamel making it stronger.

7 _____

It is very easy for acid to break tooth enamel crystal with a lot of fluoride.

8 _____

Gentle brushing with a soft-bristle toothbrush is no less effective than brushing with a stiff-bristle toothbrush.

9 _____

Dentists often recommend a fluoride treatment to their patients.

10 _____

Chapter II. Use of english

1. Lexical Cloze Tasks

a. Complete the following article by filling in one missing word in each space

Oral cancer – risk factors

75% of those diagnosed with oral cancer 1 _____ smokers. When 2 ______ smoker also drinks, the risks are even higher. In fact, people who both smoke 3 _____ drink are up to 15 times more likely to develop oral cancer than those who 4_____. If you add bad oral hygiene 5____ smoking and alcohol, then the risks are even greater.

One might think that once the patient has 6 _____ diagnosed with oral cancer, it’s too late to stop smoking and drinking. However, one of the characteristics 7 _____ oral cancer is that there is a tendency to develop a second primary oral cancer.

Approximately 15% of patients, who continue 8 _____ smoke and abuse alcohol after the first cancer is treated, go on to develop another oral cancer within five years. This increases to as high as 40% after five years. Moreover, patients 9 _____ smoke have a lower response to radiation therapy and their survival rate is lower. It is therefore imperative that the patients change 10 _____ lifestyle immediately.

b. Complete the following article by filling in one missing word in each space

PAIN

Pain is a vital part of our body’s defences, and 1 _____ it we could not survive.

Pain warns us what things 2 _____ dangerous, and so helps us avoid damage to our body. If the body is already damaged, pain helps with healing because 3 _____ makes us protect our injuries. Some babies are born with a rare condition that makes them unable to 4_____ pain. They do 5 _____ learn the lessons that pain teaches, and as a result suffer many fractures and infections.

Pain happens when nerve endings in our skin and our internal 6 _____ send messages through the central 7 _____ system to our brain. The brain itself 8 _____ feel pain.

There are two types of pain – acute pain, which lasts a short time and 9 _____ removed when the cause is cured, and chronic pain, which can last a lifetime and cannot usually be treated. Chronic pain must 10 _____ managed using drugs or other methods.

c. Complete the following article by filling in one missing word in each space