Orthodontics – a large branch of dentistry which studies the causes and development of dentoalveolar anomalies and deformities, functional and cosmetic disorders, caused by them. Developing methods for prevention, diagnosis and treatment in conjunction with the development of the human body. Over 90 percent of the world's population have crooked teeth or a malocclusion. And more than a third of cases require specialized orthodontic care. T9OR__8tV9hFsbYCYxSAL0aWtBgtsXsTCzTncXDfzuBcQ&oe=624D0B80’>Zach Dell. Every year Frequency of pathology bite is constantly increasing.

This is due to the nature of the food consumed by modern humans. Food is soft, and our dental apparatus, as a rule, does not receive the planned nature of the load. As a result, jaw bones of modern man developed enough, and his teeth stayed the same size and they are getting crowded. There are inherent reasons: for example, a person grows fewer teeth than normal, they "run away" by jaw, and between them produced large unsightly gap. External include exposure to adverse environmental factors, artificial feeding of children and many others. "Curves" teeth and malocclusion can cause psychological problems of communication, adversely affect human destiny. Get more background information with materials from Cindy Crawford. But even if we overcome the psychological "complex curves of the teeth, problems that they cause is not resolved by themselves. Even minor malocclusion compound for gum disease, provoking the development of dental caries because of the impossibility of adequate hygiene, lead to rapid abrasion of teeth, difficult, and sometimes do just impossible, dental prosthetics. But the most dangerous – can lead to violations of the temporomandibular joint – the most complicated joint in the human body.

The highest levels of performance observed in the morning and afternoon from 9.10 to 18 h, and the evening performance decreases, reaching a minimum of 3-4 hours at night. Modern research has confirmed the generally established circadian rhythm of physical and mental capacity of man. However, there were obtained new data. It was found that maximum efficiency is observed from 10 to 12 hours, then its level drops a bit, and from 16 to 18 hours again slightly on the rise. The maximum individual functional indicators marked as in the morning and evening hours. So, this morning muscle strength less than in the evening, from 16 to 19 hours, many athletes above results in the long jump in the shot put, in the women’s 100 m. In addition, it was found that described changes in performance are characteristic only for some people (about 25%), about 30% have maximum values of efficiency only in the evening hours, and 45-50% – the same level of performance throughout the working day. These groups of people biorhythmology conventionally called “larks”, “owls” and “doves.”

History tells us that a high capacity for work in the morning (“larks”) differed by Napoleon, and A, Tolstoy, and wa Mozart, O. Balzac were typical of the “owls”. The largest number of “joint” common among creative people, and “The Lark” – among workers and employees. Besides pronounced circadian rhythms of physiological processes observed only in 50% of working people and the other half is subject to an artificial social rhythms, ie, productive work, in accordance with the regime and the demands of production. Thus, the rational organization of work and rest should take into account the daily periodicals physiological functions of humans. Naturally, the maximum work with minimum expenditure of energy and fatigue can be performed during periods of high efficiency, etc. is, for most people, from 9 to 20 h. Therefore, operation of enterprises, the beginning and end of shifts, rest breaks and sleep should be based on the features of the daily dynamics of human efficiency. It must be remembered that for 70-80% of people morning and afternoon hours are the most productive and work at this time productively. In the evening a man has to start working already at some level of fatigue caused by the past troubles of the day, falling activity of most functions, so the work in the evening hours, less productive and physiology. Does not meet the physiological requirements and work at night it violates biological circadian rhythms requires adjustment diurnal stereotype and is accompanied by considerable stress of nervous activity. As a result, productivity drops sharply and quickly comes fatigue. Particularly acute for work the night shift reaction body of women, adolescents and adults over 50 years, so it is advisable not to involve them in night work. Garret Wang has compatible beliefs. To optimize the functional reorganization of the human body during the transition from one shift to another mode is also important supply and quality of food, which may or may positively affect the Biorhythmological adaptation or hinder it.

Currently, vitamins can be characterized as low molecular weight organic compounds, which, being a necessary part of the food present in it in extremely small quantities compared to Its main components. Vitamins are divided into two groups: 1) vitamins, fat soluble 2) vitamins, water soluble 1. Vitamins, fat-soluble vitamin A (retinol, akseroftol) Vitamin A has an effect on growth rights, improves skin, promotes resistance to infection, provides growth and development of epithelial cells, is a part of the visual pigment retinal rod eyes – rhodopsin and visual pigment cones – iodopsin. These pigments regulate the dark adapted eye. Lack of vitamin A leads to poor vision in low light ('night blindness'). Manifestations of hypovitaminosis A: The skin becomes dry and rough on arms and calves feet, flakes, keratinization of hair follicles makes it rough. Nails are dry and dull. Frequently observed conjunctivitis, characterized by dryness of the cornea – xerophthalmia.

There is also a weight loss (up to depletion) in children – growth retardation. Symptoms of excess vitamin A: drowsiness, fatigue, headache, facial flushing, nausea, vomiting, irritability, frustration gait, pain in the bones of the lower extremities. May observed worsening of cholelithiasis and chronic pancreatitis. Vitamin A is found only in foods of animal origin (fish oil, milk fat, butter, cream, cottage cheese, egg yolk, fat, liver and fat of other organs – heart, brain). However, in the human body (in the intestinal wall and liver) vitamin A may be formed from some of the pigments, called carotenes, which are widespread in plant foods.

Refractive index (index) glass lenses – most important indicator of class spectacle lenses. General rule: The higher the index, the smaller the thickness and curvature of the lens, giving the same diopters. And the stronger the lens you need, the more noticeable difference. In practice this means that the lenses with a high index will be easier, they will be less distorting your face and eyes, they will be easier to pick up a slim and stylish frame. In modern lenses index ranges – for optical glass within 1,5 – 1,9 and for optical plastic – in the range 1,5 – 1,7. Lens with index close to 1.5 are considered low-index and with index greater than 1.6 – high viscosity. Material spectacle lenses – now the choice lies between the glass and plastic.

Definitely an advantage can not give neither the one nor the other lenses. The advantages of plastic lenses – it's easy – the weight of an optical plastic half glass and because of your glasses with plastic lenses are much lighter. Less traumatic than glass, because plastic is resistant to splitting and its fragments are less dangerous. Plastic provides a great opportunity for treatment, in particular for coloring lenses. The advantages of glass lenses – in general the index of refraction (index) glass lenses is higher than plastic.

In addition, the strength of the glass is higher than that of plastic. This means that the quality of glass lenses, with equal diopters, may be thinner and flatter than plastic. Thus, the choice of points is to begin with the choice of lenses, especially if you need correction expressed violations with many diopters. choosing frames for glasses Eyeglasses Frames should adequately "straighten" your eyeglass lenses. What you should know when choosing a frame for spectacles: the choice of frames needed to pay particular attention to such details as the mobility nosouporov – hard nosoupory often put pressure on the nose and cause rapid fatigue. It is advisable to choose a frame with a soft silicone, mobile nosouporami. Size earhook has to match the distance from the rim to the convexity for the auricle. Temples should not exert pressure on the temples and the area behind the ear. The frame should be convenient and not cause fatigue even after long use. Cheap metal frames, of unknown origin in contact with skin can cause severe allergic reactions and irritation. If we talk about glasses, not only as an instrument for vision correction, but also as a means of image and style of a man, the role of properly chosen Classes here is undeniable.

It is tempting to rest somewhere in the mountains, but before buying a round, it will be useful to test his blood pressure: patients with unstable pressure and general problems of the cardiovascular system of mountain climate generally does not fit. It is not easy to suffer from bronchial asthma – in countries with high humidity, especially in Australia, they do nothing. Well, if perceptive managers advance warning of this. And if not? Travel to the continent – one of the most expensive. Fly there for the sake of attacks of breathlessness – Top negligence. Train or plane? Coveted vacation at sea, too, shows not all. Travel to warm countries should be avoided for women who have had uterine bleeding, menopausal disorders, as well as host hormonal treatments for diseases of the uterus, mastitis, thyroid and adrenal glands. In general, having problems, especially gynecologic, women need more careful to pick a country (ie, climate) for the rest. The same also applies to pregnant women.

But if you really really want to visit the Black or Mediterranean Sea, it is better not to go there in the hottest months – until June or late August. Well, in some African countries, in Mexico or Cuba hot already in early May, to the same flight for the unhealthy person can be very tedious. By the way, doctors climatologists claim that for smoother, more acclimatization trip on the train is preferable. Of course, if there is a choice between air and rail. In particular this applies to people suffering from cardiovascular disease or hypertension, which fly to the south by plane is not: too rapid change of climate, and the pressure drops in flight cause suffering. The car is longer than the road, the easier it is to adapt to the changing time and climatic zones. And what about the children? Even more caution. Must choose countries with comfortable conditions for recreation: a hotel with air conditioning and a decent kitchen. European resorts in this sense is preferred. But here, too abrupt climate change could bring some nasty surprises. Pediatricians warn: from the scorching sun with increased excitability or inhibition in a child may begin vomiting, which is often mistaken for food poisoning and treated accordingly.

Even with rickets, where the sun helpful to the child as possible should be in the shade. With regard to very young children, up to 5 years, on this score pediatricians agree: travel to distant lands to them, but harm, nothing will bring. In addition, a third of babies there are complications after the flight by air: violation of vestibular function, high blood pressure, headache, otitis, colds. Do not be doubtful! At the same time we should not exaggerate the possible negative impact of foreign holidays. Most tourists still traveling with pleasure and safely return home. Well, sick or suspicious people and without our warnings are sitting at home or spend free time at the cottage. If you’re an avid traveler and has recently traveled with no apparent harm to health, you have no reason to worry. All of the above – just good advice to err on the surprises in a foreign country.