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The History of the Toothbrush

1. Read the text and give the appropriate headings to each paragraph.

The exact origin of mechanical devices for cleaning teeth is unknown. However, since ancient times, individuals have chewed twigs from plants with high aromatic properties. Chewing these twigs freshened breath and spread out fibres at the tip of the twig, which were then used for cleaning the teeth.

During the Tang dynasty (618 – 907A.D.) the Chinese invented the toothbrush with a handle and bristles. They used hog bristles similar to those in some contemporary brushes. In 1780 in England, William Addis manufactured “the first modern toothbrush”. This brush had a bone handle and holes for placement of natural hog bristles. In the early 1900s, celluloid began replacing the bone handle. This change came about World War I, when bone and hog bristles were in short supply. As a result of this, nylon bristles were introduced.

Initially, nylon bristles were copies of natural bristles in length and thickness; however, they were stiffer than the natural bristles. They did not have the hollow stem of the natural bristles; therefore they did not allow water absorption. Other advantages of nylon bristles, or filaments, were the ability to form the bristles in various diameters and shapes, and to round the bristles ends to be gentler on gingival tissues.

For various reasons, tooth brushing spread throughout the world. In the seventh century, Mohammed made rules about oral hygiene: specifically, he made it a religious obligation. In 1916, Dr. Alfred C. Fones, the founder of dental hygiene, wrote a textbook Mouth Hygiene, which directed dental hygienists to teach specific tooth brushing methods to schoolchildren.

In 1939 the first power tooth brush was developed in Switzerland. This brush had a power cord and was introduced in the United States in the 1960s under the name Broxodent. This product was a great success. Soon afterwards battery-powered brushes were developed and marketed.

2. Find equivalents to the highlighted words:

energy supply

equipment

characteristics

hand

preference

limit

duty

empty

brush

scrub

piece of hard tissue making up a skeleton

3. Explain in Russian the meaning of the words in bold.

4. Speak about 4-5 facts from the history of the toothbrush.

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