V. Read the sentences and define the functions of Participle I and II. Translate the sentences.

1. The connective tissue attachment destroyed by the periodontal disease may be regenerated.

2. Mineral deposits found on the tooth surface are usually removed.

3. Microbes colonized at the gingival crest are the cause of periodontal disease.

4. As shown by archaeological studies and the historic literature periodontal disease has a long history.

5. The organisms may become infiltrated with mineral deposits forming calculus.

6. Plaque and calculus affecting teeth must be removed.

7. An erupting tooth was affected by periodontal disease.

8. This is achieved at present by the dentist educating and supervising the child through adolescence and adulthood.

VI. Use Participle I or II instead of subordinate clauses.

1. The direct cause of periodontal disease is the adherent colonized microbial mass which is found on the tooth surface at the gingival crest in the sulcus and in the periodontal pocket.

2. The organisms nearest the tooth surface may become infiltrated with mineral deposits that form calculus.

3. This is achieved at present by the dentist who educates and supervises the child through adolescence and adulthood by early discovery and removal of all plaques.

VII. Read and translate the sentences paying attention to the subordinate clauses.

1. When present in the water supply fluoride automatically forms part of the diet during the period of tooth formation.

2. If used regularly fluoride toothpaste gives a slightly greater caries reduction than ordinary toothpaste.

3. If left unchecked gingivitis can progress to a more severe condition called periodontitis.

4. Second teeth may become loose and, if untreated, can be lost.

5. The patient is given a mirror to see the shade, shape and arrangement of the teeth, and if dissatisfied with them, any necessary adjustments can then be made in the surgery.

6. These chemotherapeutic agents when used properly will control the development of disease.

VIII. Read and translate the text.

Text A. Periodontal Disease

    Archaeological studies and the historic literature have shown periodontal disease has affected mankind since early in evolution. Recent epidemiological studies have shown that the disease is the major cause of tooth loss after 35 years of age.

    The direct cause of periodontal disease is the adherent colonized microbial mass found on the tooth surface, at the gingival crest, in the sulcus and in the periodontal pocket. The pathogenesis of periodontal disease begins at the time the tooth erupts. The tooth is the stony foundation to which the microbes adhere and on which they colonize. As the microorganisms develop on the tooth surface the first microscopic changes occur on the gingival next to them. These are proliferation and desquamation of epithelium, serous and cellular exudation and lysis of connective tissue fibers. The organisms nearest to the tooth surface may become infiltrated with mineral deposits forming calculus.

    Lysis of the circular fibers occurs. With loss of the supporting connective tissues the gingiva loses its firmness, stands away from the tooth surface; the sulcus deepens and the periodontal pocket develops.

    The most important therapeutic aim is the removal of plaque and calculus by the therapeutist. There is no doubt the gingival inflammation subsides and can be maintained at a very low level by these procedures.

    The ideal future task may be the generation of bone and connective tissues attachments which have been destroyed by the disease process. Significant regeneration of bone and connective tissue may be achieved by grafting a number of substances but these procedures are experimental at present.

    The most important aim is prevention of the occurrence of periodontal diseases. This is achieved at present by the dentist educating and supervising the child through adolescence and adulthood by early discovery and removal of all plaques.

    Our best hopes for the future lies with the discovery and development of effective chemotherapeutic antiplaque agents. It seems realistic to expect that within the lifetime of many of us there will be agents which, when used regularly, will effectively prevent plaque formation or at least control its pathogenic components. The periodontal disease can be halted and healthy dentition achieved.

IX. Answer the questions.

1. What is the main cause of the tooth loss after 35 years of age?

2. What is periodontal disease caused by?

3. What changes occur because of the microorganisms in the mouth?

4. What is the most important therapeutic aim of a dentist?

5. What does preventive aim lie with?

6. How can periodontal disease be halted and healthy dentition achieved?

7. Have the effective anti-plaque agents been discovered yet?

X. Complete the following sentences.

1. The major cause of … (потеря зуба) after 35 years of age is … (заболевание периодонта).

2. Periodontal disease … (вызывают микробы).

3. The first microscopic changes affecting the … (прорезывающийся зуб) are … (разрастание и шелушение эпителия, серозный и клеточный экссудат и распад волокон соединительной ткани).

4. Gingival inflammation subsides when … (удаляют зубной налет и камни).

5. With loss of the supporting connective tissues the gingiva … (теряет свою прочность).

6. Significant regeneration of bone and connective tissues attachment destroyed by the disease may be achieved by …. (пересадка целого ряда веществ).

XI. Fill in the gaps with the prepositions.

1. Periodontal disease has affected … mankind … early … evolution.

2. The tooth is the stony foundation … which the microbes adhere and … which they colonize.

3. As the microorganisms develop the tooth surface the first microscopic changes occur … the gingiva next … them.

4. … loss … the supporting connective tissues the gingival loses its firmness, stands … the tooth surface.

5. Gingival inflammation can be maintained … a very low level … these procedures.

6. This is achieved … present … the dentist educating and supervising the child … adolescence and adulthood … early discovery and removal … all plaques.

7. It seems realistic to expect that … the lifetime … many … us there will be agents which will effectively prevent plaque formation.

8. Our best hopes … future lie … the discovery and development … effective chemotherapeutic antiplaque agents.

XII. Translate the following word combinations.

археологические исследования, поражать человечество, потеря зуба, десневой выступ, бороздка и десневой карман, разрастание и отшелушивание эпителия, распад соединительнотканных волокон, минеральные отложения, терять прочность, без сомнения, воспаление уменьшается, восстановление кости, юность и взрослое состояние, противобляшковые препараты