Vocabulary

1) Match the words to their definitions. Say what types of caries do you know.

A - Calcium - B - Calculus – C – Aerobic bacteria – D – Caries – E – Demineralization – F – Secondary caries – G – Root caries -

1 – bacteria that require oxygen for survival 2 – a progressive destruction of any kind of bone structure, including the skull, ribs, teeth, and other bones. 3 – the fifth most abundant element by mass in the human body and a major component of the teeth 4 – caries located on the root (cementum) of a tooth, which frequently increases with age due to increased gingival recession, or exposure of root surfaces 5 – the loss of mineral from the tooth because of bacterial acids, acid foods (soft drinks, acid juices, etc), or even toothbrushing abrasion. 6 – caries that develop around a restoration. 7 – calcified deposits on the teeth, formed by the continuous presence of dental plaque, sometimes called tartar.

2) Label the picture

Reading. Multifactorial Disease Process

1)Explain the words in bold

2. Read the text and answer the question “Why dental caries may be called a multi factorial process?”

Dental caries is one of the most common diseases in humans: caries causes pain and disability and can lead to infection, tooth loss and edentulism (loss of all teeth). Researchers have also discovered connections between chronic oral infections and other chronic diseases such as diabetes, osteoporosis, cardiovascular diseases and obesity.

Dental caries is a multifactorial diseases process. For caries to develop four conditions must occur simultaneously: (1) There must be a susceptible tooth and host; (2) cariogenic microorganisms must be present in a sufficient quantity; there must be frequent excessive consumption of refined carbohydrates; and this process must occur over a sufficiently long period of time.

When a tooth covered with cariogenic bacteria is exposed to a suitable substrate, such as a refined carbohydrate, the bacteria produce acid. If these conditions persist over a sufficiently long period of time, an incipient lesion develops. An incipient lesion is the initial stage of the tooth decay that has not penetrated the outer surface of the tooth. The lesion looks like a white spot on the enamel.

Each of these main factors includes a number of secondary factors, which can be introduced to either protect or further damage the tooth.

Grammar. Modals.

In English we use different Modals:

Have to/ must/ need to – express necessity or strict rules;

Don’t have to/ don’t need to/ needn’t – means “it’s not necessary”;

May/ can – means “it’s allowed”;

Mustn’t/ can’t – means “it/s not allowed”;

May/ could – means “it’s possible”;

Should – help you to give advice

1. a) Look at the table, make sentences using can or can’t.

Mary Jim Tom

make injections			√
examine the patient	√		
make professional cleaning	√	√	√
advise about oral hygiene rules	√		√
recognise symptoms of periodontal diseases	√		

b) Ask questions as in the example.

• Can Mary make injections?

• No, she can’t.

• Can she examine the patient?

• Yes, she can. etc.

2. Make the rules to obey in the hospital. Use the modals must (not), be (not) allowed to.

• no pets within the hospital;

• no smoking anywhere;

• no alcohol;

• visitors only during visiting hours;

• no loud sounds;

• no electrical devices.

3. Give advices about healthy oral hygiene.

• Brush your teeth twice a day

• Floss at least daily

• Visit your dentist regularly

• Make professional cleaning at least twice a year

• Cut down the usage of sugary products

• Use fluoride mouth rinse regularly

Ex. You should brush your teeth twice a day after meals.