III. Ознакомительное чтение (45 мин) Направлено на формирование компетенции ок-5, пк-31

Прочтите и переведите текст

Dental caries begins first inside the tooth. A white spot appears on the enamel. At this stage, the tooth can repair the affected area with the help of fluoride and minerals in saliva. But if the decay continues and breaks through the surface of the enamel, the damage is permanent. The decay must be cleaned out and the cavity filled by a dentist. Left untreated, the decay will worsen and destroy a tooth through the dentin layer and down to the pulp or nerve of the tooth. In young children, teeth that emerge have weak enamel and are highly susceptible to decay. A type of decay called baby bottle tooth caries destroys enamel quickly and is common in children.

Older adults sometimes have chronic caries: cavities that don’t seem to get any worse or do so at a very slow rate. Root caries is more common in older adults. Older adults are more likely to have gums that have receded from years of hard brushing or periodontal disease. Decay can form beneath fillings or other restorations, such as crowns. Sometimes, bacteria and food particles can slip into a tooth if a filling hasn’t been placed properly or if the filling cracks or pulls away from the tooth, leaving a gap.

Do you or your family members get cavities frequently? To prevent your teeth from decaying, you can do two things — strengthen your teeth’s defenses with fluoride and sealants, and reduce the number of bacteria in your mouth. Fluoride strengthens teeth by penetrating the tooth structure and replacing lost minerals. Everyone should brush with a fluoride toothpaste every day. Sealants are protective coatings placed over the tops of chewing teeth. They block bacteria and acids from accumulating in the tiny grooves on the chewing surfaces of these teeth. Although you can never get rid of all the bacteria in your mouth, you can control bacteria by brushing regularly and flossing daily, seeing your dentist and dental hygienist regularly. Some mouthwashes (those that contain chlorhexidine) can also help prevent decay by reducing the number of bacteria in the mouth. Chewing sugarless gums, especially those with xylitol, are also helful in reducing decay and increase the flow of saliva.

Ответьте на вопросы:

• Where (at what site) does dental caries first begin?

• What is the first stage of dental caries?

• How does decay destroy a tooth?

• Why are teeth in young children highly susceptible to decay?

• What does “chronic caries” mean?

• In what cases does decay form beneath fillings or other restorations?

• How does fluoride strengthen teeth?

IV. Устная речь (45 мин). Направлено на формирование компетенции ок-6.

Выполните упр. 7, 9, 10 стр. 41;

Занятие 14

Этапы занятия и рекомендуемая продолжительность тренировки видов речевой деятельности:

I. Изучающее чтение. Направлено на формирование компетенции ок-5

Задание1. Прочтите текст «Periodontal Diseases»:

The word “periodontal” is of Greek origin. It means “around the tooth”. Periodontal diseases are caused by bacterial infections that attack gums, ligaments and the bone structure. The mouth contains a large number and variety of bacteria. They form a sticky film called plaque. Plaque is not easy to remove, even if you brush your teeth every day. That is why it is very important not only to brush teeth, but also to clean between them and to have regular dental check-ups, including periodontal examinations. Unremoved plaque forms a porous deposit that is called tartar. It can be removed only when your teeth are cleaned in the dental office.

There are several kinds of periodontal diseases. Some of them develop slowly and without any pain, while others progress rapidly. These diseases occur at any age, but for adults they are the main cause of tooth loss.

What factors can increase risk of periodontal diseases?

• Poor oral hygiene

• Smoking or chewing tobacco

• Poor diet (inadequate and unbalanced diet makes mouth tissues less resistant to any infection)

• Some types of drugs (steroids, cancer therapy drugs, oral contraceptives and a lot of others)

• Pregnancy

• Defective fillings and bridges (as they contribute to plaque retention)

What are the warning signs of periodontal diseases?

• Easy bleeding from gums

• Swollen and red gums

• Permanent teeth become loose

• Persistent bad breath or bad taste

• Gums pull away from the teeth

• Any changes in the fit of partial dentures

What are the types of periodontal diseases?

The normal space between teeth and healthy gums is three millimeters or less. With periodontal diseases this small space develops into a pocket. The more serious is the disease, the greater is the depth of pockets.

• Gingivitis – a mild periodontal disease which develops when toxins in plaque irritate the gums, making them red, tender, swollen and easy to bleed. Three out of four adults have some degree of gingivitis.

• Periodontitis – a serious periodontal disease which occurs when toxins destroy the tissues which anchor teeth into the bone. The gums detach from teeth, and pockets are formed. Exposed teeth roots become susceptible to decay and sensitive to cold and touch. Tartar that forms below the gums inhibits reattachment of the gum tissue to the teeth. Thus, conditions for constant inflammation are created. If not treated, the affected teeth become loose in their sockets. They may fall out or require extraction by a dentist.

Задание 2. Ответьте на вопросы после текста:

• What is dental plaque?

• What does unremoved plaque form on teeth?

• What factors can increase risk of development of periodontal diseases?

• What are the symptoms of periodontal diseases?

• What is gingivitis? What symptoms can be seen in gingivitis?

• What is periodontitis? When does it usually occur?