Exercise 2 Find in the text synonyms for:

grown-ups, to catch, to contain, to reduce, a field (of dentistry), dental caries, to involve, to perform, in some cases, false teeth.





PREVENTIVE DENTISTRY
Preventive dentistry includes cleaning the teeth, removing plaque, and advising patients how to brush teeth properly and how to use dental floss (a thread which removes food particles trapped between the teeth). Studies have shown that tooth decay is decreasing in many countries as a result of preventive dentistry, improved diet, dental care, and the use of fluoride. Fluoride is a substance which can reduce tooth decay, and can be incorporated in the tooth enamel by taking tablets or drops, or by using a fluoride toothpaste. It occurs naturally in some drinking water but is also added artificially in a ratio of one part per million.The form of treatment known as orthodontics involves first X-raying the teeth, then using braces and other devices to straigthen them, to even out any gaps, and to make the teeth, gums and jaws work correctly.This treatment should be carried out while the teeth are still growing and developing, but, in a few cases, orthodontic treatment is carried out on adults.Another branch of dentistry, called periodontics is concerned with the treatment of gum disease, which is a particular problem among older people. Like tooth decay, gum disease is also caused by excess plaque, which irritatesthe gums and eventually leads to receding gums and loss of bone. Lacking support the teeth become loose and have eventually to be extracted. Regular removal of plaque is very important in the fight against gum disease.People who have lost most or all of their teeth go to the dentist to have dentures, or false teeth, fitted. In the past, dentists made sets of false teeth using real human teeth or carved ivory. Today dentures are made from a plastic called acrylic resin or from metals such as chrome, cobalt, stainless steel, or gold. Plastic or porcelain teeth can be tinted to look like natural teeth. Dentures may be either complete (when all teeth are missing) or partial (when the patient still has some teeth left).