2020-09-24
164
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.
