Dental caries dental caries is a disease of the calcified tissues of the teeth caused by the action of micro-organisms on fermentable carbohydrates. it is characterized by demineralization of the mineral portion of enamel and dentine followed by disintegration of their organic material. as the disease approaches the pulp, it produces changes in the form of reactionary dentine and pulpitis (possibly giving pain), and may result in bacterial invasion and death of the pulp. the infected necrotic pulp then produces further changes in the periapical tissues. on the other hand, the disease can be arrested in its early stages since it is possible for remineralization to occur. in addition, progress of the disease to a clinical cavity is not inevitable, and can be completely prevented by relatively simple measures. four factors are necessary to produce dental caries: • dental plaque • a suitable carbohydrate (mainly sugar) • a susceptible tooth surface • time. unfortunately, caries presents symptomatically at a relatively late stage. the patient may feel a 'hole in a tooth' with the tongue, brown or black discoloration or cavities may be seen, or frank pain may be suffered. задайте на вопросы к тексту( общий. альтернативный, спец, разделительный и к подлежащему)

6aKalL 6aKalL    2   09.06.2019 12:41    2

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