Brushing our teeth — such a (1) activity today, has been around for a long time. Imagine: the ancient Egyptians (2)! We know this today because they also had the good habit of being (3) with all their treasures ... So we were able to discover that tombs from 3,000 years before Christ contained small tree branches whose ends had been frayed into soft fibers. It's (4) to imagine an Egyptian stopping to brush his teeth after a meal, on his break from building a pyramid!
(5), however, was invented by the Chinese in the 15th century and brought back to Europe by travellers. This toothbrush was made of hairs from the neck of a Siberian wild boar which were fixed to (6). The people of the Occident, however, found the wild boar hairs too (7). At the time, very few people in the Western world brushed their teeth, and those who did preferred horse hairs, which were softer than those of the wild boar! In Europe, it was more (8) after meals to use (9), or one made of silver or copper.
Other animals'hair was also used for dental care, right up until this century. But it was the poor Siberian wild boar that (10) it. The animal was imported for its neck hairs for a long, long time ... in fact, until nylon was invented, in the 20th century!
In 1937, in the Du Pont laboratories in Nemours, U.S., nylon was invented by Wallace H. Carothers. In 1938, this new material became a symbol of modernism and prosperity through the (11) of nylon stockings and of Dr. West's miracle toothbrush with nylon bristles. The wild boars were finally (12)!
At first, even if there were many advantages to using this new brush instead of the one made with wild boar hairs (which fell out, wouldn't dry very well or became (13)), the consumers were not entirely satisfied. This is because the nylon bristles were very stiff and hurt the (14). In 1950, Du Pont improved their toothbrush by giving it (15) bristles.
Today the brands, types, and colours of toothbrushes on the market are almost endless. In spite of this, certain African and American populations still use tree branches to care for their teeth!
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