Vocabulary

Fill in the gaps with the words from the box

Dental surfaces deposits periodontal caries tooth prevented

Soft microbial 1) _____ plaque continually forms on the tooth 2) _____, and is the primary agent in the development of dental 3) _____ and 4) _____ diseases. If plaque biofilm is completely removed with the self-care procedures, dental caries and periodontal diseases can be 5) _____. Unfortunately, the majority of the population is unable, uninstructed, or unwilling to spend the time to adequately remove plaque from all 6) _____ surfaces. Plaque 7) _____ may be removed either mechanically or chemically. Incidentally, the toothbrush is the most commonly used instrument in plaque removal.

Grammar. Comparisons

In English we use Comparative degree to compare two things or persons.

Ex., He works faster than me.

This procedure is more complicated than the previous one.

We use Superlative to compare the person or the thing of all persons or things or in the (world).

Ex., He is the fastest in the group.

This procedure is the most expensive (of all).

To form:

	Positive	Comparative	Superlative
1) one-syllable	fast big small late	faster bigger (than) smaller later	fastest (the) biggest smallest latest
2) two and more syllables	difficult complicated interesting	more difficult more complicated more interesting	the most difficult the most complicated the most interesting
3) irregular	good	better	the best
	bad	worse	the worst
	little	less	the least
	many much	more	the most
	far	farther further	the farthest the furthest

1. Complete the table:

Small	…	The smallest
Little	…	The least
Dangerous	….	…
difficult	…	…
…	…	The most complicated
…	worse	…
…	healthier	…

2. Form the appropriate degree of comparison.

1. Your brother is ______ (tall) than you.

2. This chair is _______ (comfortable) than that one.

3. Garry is the _____ (old) in the family.

4. She is the ______ (beautiful) girl of all I know.

5. Tom is the ______ (good) student in the group,

6. He is the ________ (skilful) of all the students.

7. His work is _______ (complicated) than yours.

3. Read the text and choose the degree of comparisons. Form the comparative and superlative of the highlighted words.

Nylon Versus Natural Bristles

The nylon bristle is superior to the natural hog bristle in several aspects. Nylon bristle flex as many as ten times more often than natural bristles before breaking; they do not split or abrade and are easier to clean. The shape and stiffness of nylon bristles can be standardized. Natural bristles diameters vary greatly in each filament. This can lead to wide variations in the resulting texture.

Reading

Toothbrushing Time and Frequency

For many years, dental providers advised patients to brush their teeth after every meal. Research has indicated that, if plaque is completely removed every other day, no harmful effects will occur in the oral cavity. On the other hand, very few individuals completely remove plaque; therefore, frequent brush is still extremely important and recommended. This repeated brushing will maximize sulcular cleaning as a measure to control periodontal disease, as well as introduce more frequent use of fluoride dentifrices to control caries. In areas with periodontal pockets, even more frequent oral hygiene procedures are indicated.

Thorough tooth brushing requires a different amount of time for each individual, depending on such factors as the tendency to accumulate plaque and debris; the person’s psychomotor skills; and the adequacy of clearance of foods, bacteria and debris by the saliva. Often a compromise is made by suggesting 5 to 10 strokes in each area or by advocating the use of the timer. A person should be encouraged to brush for up to 2 minutes and to use a timing device. In addition, many power toothbrushes are designed with built-in timers that signal the patient when to move to another area of the mouth; the timers shut off when the designated number of minutes has passed.

Patients tend to apportion more time and effort on the facial areas of the anterior teeth. Often, right-handed people do not brush the right side of the arch as well as the left side; left-handed people similarly neglect the left side of the arch.

Make up phrases and explain them in Russian:

Dental, built-in, extremely, harmful, brush, completely, remove, on the other, power, timing

1 ________ providers

2 _________ smb’s teeth

3 _________ removed

4 _________ effects

5 _________ plaque

6 _________ hand

7 _________ important

8 ________ toothbrushes

9 _________ device

10 ________ timers

Use these phrases in your own sentences.

UNIT 7. WATER FLUORIDATION