TOOTH BRUSHING AND PLAQUE REMOVAL
Brushing after meals can only be effective if it removes plaque (a film of material composed of masses of bacteria in a sticky glycoprotein matrix which adheres the surfaces of teeth). The object is to clean every accessible tooth surface, thus removing food debris and plaque and massaging the gum margin. Plaque removal is of great importance in the etiology of dental disease because some bacteria can metabolize sugar and form acid, and others produce harmful products which can cause inflammation of the gums (gingivitis) and destruction of the periodontal tissues (periodontal disease). Both plaque which is allowed to remain in the gingival previce between the gum margin and neck of the tooth and that occurring on the tooth surfaces above the gum margin can calcify and harden to form tartar (sub-gingival and supra-gingival calculus). This tends to retain further harmful accumulations of bacteria in contact with the periodontum.
Toothbrushes with a small head and medium bristles are probably the most effective. The brush is rinsed and toothpaste added. Several strokes are used on each section of the mouth. Buccal, lingual, mesial and distal surfaces are cleaned by a rotary motion from gum to tooth. Occlusal surfaces are cleaned by a scrubbing action. Finally the gingival margins are cleaned by a backwards and forwards motion which must be done gently to avoid abrasion of the necks of the teeth.
Each jaw is done in turn1 and the mouth is then thoroughly rinsed with warm water to expel food debris dislodged by the toothbrush. Brushes should be washed and dried afterwards.
Correct and effective tooth-brushing in the way described requires time, knowledge and skill. Lack of these requirements makes brushing ineffective as a preventive measure. Although it is no better than2 a properly used ordinary toothbrush it may be useful for many people (particularly children and physically handicapped persons) to use an electric toothbrush. Teeth are cleaned rapidly and effectively as most of the movements are done automatically.
'Each jaw is done in turn... — Кожен ряд чиститься по черзі.
2 Although it is no better than... — Хоча вона не краща за
Exercise 7 . Answer these questions:
1. When can brushing be effective?
2. What is the object of toothbrushing?
3. What toothbrush is the most effective?
4. How is the brush used?
5. By what motion are buccal, lingual, mesial cleaned?
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6. How are occlusal surfaces cleaned?
7. Why must the gingival margins be cleaned by a backwards and forwards motion?
8. Why should the mouth be thoroughly rinsed?
9. Do many people know how to brush the teeth correctly and effectively?
10. How can the process be made simpler?
11. Why are teeth cleaned rapidly by using an electric toothbrush?
12. Is it better than a properly used ordinary toothbrush?
Exercise 8 . Find the synonyms in the text:
To stick, covering, to delete, accurately, concentration, tenderly, movement, to need some time, invalid, quickly, especially.
Exercise 9. Make up a dialog using special questions and active vocabulary:
Exercise 10. Say if the sentences are right or false:
1.Brushing after meals can be effective even if it doesn’t remove plaque (a film of material composed of masses of bacteria in a sticky glycoprotein matrix which adheres the surfaces of teeth).
2. The gingival margins are the last to be cleaned by a backwards and forwards motion which must be done gently to avoid abrasion of the necks of the teeth.
3. Only the plaque which is allowed to remain in the gingival previce between the gum margin and neck of the tooth can calcify and harden to form tartar (sub-gingival and supra-gingival calculus).
3. Effective tooth-brushing in the way described in the text is quite an easy procedure.
4. People with no physical defects should use mechanical tooth-brushes.
5. The teeth of each jaw must be brushed simultaneously and the mouth then must be thoroughly rinsed with warm water to expel food debris dislodged by the toothbrush.
6. Buccal, lingual, mesial and distal surfaces are cleaned by a scrubbing motion from gum to tooth.
7. It is well-known that electric tooth-brushes are apparently more effective than the mechanical ones for all the person
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