Page 3 of 73 CARIES OF TEETH
Caries — the progressing destructive defeat of solid tissues of tooth. This basic disease of an oral cavity at children. Uncured caries conducts to final fracture of teeth.
Etiology. As a cause of illness consider several interconnected factors. Process arises under the influence of microorganisms, mainly streptococci. They emit polysaccharides which form a gelatinous plaque on a tooth surface. To a plaque a large number of bacteria which decompose carbohydrates, especially sucrose sticks, and synthesize organic acids. Such acids at first dekaltsifitsiruyug an adamantine substance of tooth (which ability to resist to dissolution is very variable), and then cause a lysis of proteins in an organic matrix that conducts to final fracture of the struck part of tooth.
Concurrent factors. Age. Caries — an illness of mainly children's and teenage age. At children who badly eat and do not follow rules of hygiene, caries is most expressed at the age of 4 — 8 (milk teeth) and 12 — 18 years (second teeth).
Fluorides. Availability of fluorides in an adamantine substance of tooth increases its resilience to the dissolving effect of acids. Besides, fluorides brake products of acids microorganisms and promote tooth tissue remineralization in those sites where it is broken. In the area where the content of fluorides in drinking water of mg/l or above, the number of cases of caries among children are on average 60% less than where concentration of fluorides in water is lower than 0,5 has some. The maximum decrease in frequency of caries is observed in those areas where drinking water contains amount of fluorides, optimum for this district and climatic conditions. Their high concentration (2 — 2,5 mg/l) leads to emergence of "speckled" enamel. Enrichment of drinking water fluorides and their application on a surface of tooth are most effective in districts with the lowered content of salts of fluorine in water; at optimum concentration of fluorides such measures are less effective.
Food. Development of caries is promoted by such important factor as the use between meals of the sweets and drinks containing sugar, especially sucrose. Big harm is done by the use of creamy fondants, lollipops, "toffees" which stick to teeth, creating long contact of food sugars with enamel. These sugar serve as nutritious substrate for the teeth of bacteria which are on a surface which produce the acids destroying teeth. It should be noted that the sugar eaten with other food has smaller povreyaedayushchy effect thanks to its more rare reception, detergentny action of food, and also buffer properties of food and the saliva neutralizing acids.
If children are put to bed with a small bottle of milk or other sweetened liquid, it leads to accumulation of sugar in an oral cavity. The acids produced by bacteria for which sugar serves as substrate lead to development of early widespread caries. In this case distribution of destruction from upper foreteeth to back is an important diagnostic character; the lower foreteeth are rather protected by a pacifier and language. Such practice, apparently, the most frequent reason of heavy caries at children till 3 flyings.
Hygiene of an oral cavity. Non-compliance with hygienic requirements (rinsing of a mouth and toothbrushing by a brush, especially after food) leads to a delay in a mouth of the remains of food. The main goal of cleaning and washing of teeth — to remove the containing plaque bacteria, to reduce thus quantity of microorganisms in an oral cavity, to improve contact of remineralizing components of saliva with a surface of teeth. In prevention of caries and early stages of diseases of a periodontium an important role is played by parents who train the child in hygienic procedures and monitor their observance.
General state of health. At the children weakened, having chronic diseases the quantity and bacteriostatic properties of saliva can be reduced. In such cases toothbrushing after each food is of particular importance. Preventive measures are especially important for children who cannot receive the regular stomatologic help.
Clinical signs. Caries arises in places of accumulation of plaques (in blind poles and grooves of a chewing surface of back teeth, on lateral surfaces and on necks of teeth at gingival edge). In one cases process quickly extends in depth of tooth fabric, develops in others unevenly and slowly. Quickly penetrating caries is characteristic of children, slow intermittent process is more often observed at people of middle age. Visible defect on a tooth surface often is a sign of more extensive internal defeat. The dentine is less mineralized, than enamel, and is exposed to destruction easier.
Prevention. The most effective measure of prevention of tooth caries is natural or artificial fluoration of drinking water. If the content of fluorides in water is lower optimum (about 1 mg/l), then reception of fluorides brings a certain benefit. At concentration of fluorides lower than 0,3 mg/l it is necessary to appoint fluorides inside in a dose of 0,25 mg/days, since 6-month age, and in a dose of 0,5 — 1,0 mg/days (1,1 — 2,2 mg of sodium fluoride) after the first year of life. Doses of fluorides reduce if their concentration in water is in limits of 0,3 — 1,0 mg/l. The positive effect is reached by means of peroral drugs of fluorine even if teeth were cut through long ago. It is explained by penetration of fluoride into thickness of enamel and direct antimicrobic action. Efficiency of drugs increases if they long are in an oral cavity. Therefore, if liquid fluorinated drug is appointed, the single dose should be held long at a cheek, slightly inclining the head on one side; it is the best of all to use tablets for chewing. Such drugs it is not recommended to children to appoint younger than 6 years in districts where the content of salts of fluorine in drinking water exceeds 0,7 mg/l.
Use of drugs of fluorine does not replace fluoration of public sources of water supply as this measure with considerably smaller material inputs provides adequate amount of fluorides all children of this district.
So far convincing data on are not obtained whether reception of fluorides by pregnant women influences caries frequency at children.
If process of destruction of teeth began, then courses of applications of fluorides on the teeth conducted 2 times a year increase the content of fluorine in an adamantine substance of tooth. Such treatment gives a positive effect irrespective of whether concentration of fluorine in drinking water is sufficient.
More rare meal, and also refusal of the use of sweets and sweet drinks between meals can reduce the frequency of new cases of caries considerably. It is not necessary to accustom the child to a small bottle with milk during a dream. If at the child such habit was already developed, then the small bottle should be replaced with a milk cup, and then to brush teeth a brush; such zamepa is better, than gradual refusal of milk for the night.
Treatment of active process in milk and second teeth reduces quantity of microorganisms in oral cavities and respectively probability of damage of healthy teeth. If at the child the tendency to fast progressing of caries is noted, then it is necessary to perform inspection of teeth each 3 months, but not in 6 months.
As primary prevention of caries mechanical removal of plaques and the remains of food is recommended by a brush or a waxed thread. Procedure is carried out as follows: the small child is put on knees, one hand open to him lips, and another is brushed by teeth. To begin to brush teeth it is necessary from the moment of emergence of the first milk tooth. Toothbrushing by means of a waxed thread is applied when teeth do not manage to be brushed. Correctly trained child usually easily carries out such procedures without assistance.
The oral cavity can be considered as the chewing mechanism. Chewing surfaces of the resisting back teeth are closed, and then displaced relatively each other, turning dense pieces of food into soft wet weight. The food gets to a zone of contact of chewing teeth thanks to action of buccal muscles and language. The nibble of food is carried out by cutting edges of front upper and lower teeth at the movement of a mandible.
Smykaniye of jaws occurs owing to reduction mainly of chewing and temporal muscles. Together with internal alate muscles they create a high pressure in the place of contact of teeth-aptagonistov. If all chewing teeth at the same time contact, then pressure is evenly distributed on a tooth arch. At malocclusion when only a few teeth touch each other, the same force influences much smaller square. Bite pathology — a basic reason of loss of teeth at adults. Therefore at children's age it is necessary to take the necessary preventive measures directed to creation of the correct contact between an upper and lower tooth arch that has both physiological, and cosmetic value.
3 main types of a bite (fig. 12-1) are known. Character of a bite is defined at close jaws when heads of joint shoots of a mandible hold the most back position in sockets of temporal bones. At the I type (norm) chewing surfaces of the lower painters are slightly kpered and knutr from the corresponding surfaces of upper teeth. At such position of jaws face contours are normal. At the II type of a bite the lower painters are located kzad and knutr in relation to upper painters. It is the most frequent option of malocclusion; it is observed in a varying degree approximately at 45% of all people. Increase in distance between front upper and lower teeth is promoted by a habit to suck fingers or to press language on teeth. An external sign of such retrognatichesky bite is the sloping chin. The arrangement of the lower painters of a kpereda from the resisting upper teeth is characteristic of the III type of a bite. Respectively foreteeth directly resist each other or the lower cutters are pushed forward in relation to upper; at the same time the chin sharply is given (prognathism) forward.
Crossbite. At a normal bite the lower teeth are located several knutra from upper so buccal hillocks or cutting edges of the lower teeth fall on the center of teeth antagonists. The opposite state is designated as a crossbite.
Fig. 12-1. Classification of types of occlusion. Typical dependence between a profile of the person and a type of occlusion is shown. (From: Moyers R. E. Handbook of Orthodontics. Ed. 2. Chicago, Year Book Medical Publishers, 1963.)
Open and closed bite. If painters are closed correctly, and the lower cutters are located before upper, such bite is called open. If the lower cutters are for upper, then speak about a closed bite. At sharply expressed deep closed bite the lower cutters can injure a mucous membrane behind upper cutters.
The most frequent reason of malocclusion — genetic defect. Among other etiological factors it is possible to call a chin protrusion at an acromegalia (the III type of a bite). Besides, the habit to suck a finger or to press language on a lingual surface of teeth matters. The injury of its joint shoots can influence growth of a mandible.
Treatment should be begun depending on weight of malocclusion. In many cases the cross, open, closed or unsharply expressed bite of the II type can be corrected at once after establishment of the diagnosis. In most cases malocclusion II and III types gives in to correction after a prorezyvaniye of all second teeth easier (except for 3 painters).
Also the inborn edentia or extraction of teeth can be the cause of malocclusion. In such cases denture treatment is necessary to fill free space. X-ray inspection has to precede drawing up the correct treatment planning.
12.9. INJURIES OF TEETH
The risk of accidental injury of teeth increases at a protrusion of foreteeth (malocclusion of the II type) or a protrusion of upper cutters owing to a habit to suck a finger or to press
on teeth language; the teeth acting forward should be put in; the correct situation as soon as possible after a prorezyvaniye of constant cutters. Quite often injuries of teeth occur during sports activities. There are individual means of protection, teeth and them it is necessary to use. Urgent treatment of changes, and shifts increases probability of preservation and the subsequent alignment of teeth. Treatment of soft tissues with the purpose to prevent development of periodontitis has to precede orthodontic measures.
Change of cutters. At blow upper cutters as they are the most front firm educations in an oral cavity are usually damaged. Most often there are changes of crowns and roots of these teeth. If the line of a change of a crown does not pass through a pulp cavity, treatment is limited to closing of the bared dentine and cosmetic prosthetics. In that case when the cavity of a pulp is opened on a small site, quickly taken measures yield good result. At more extensive defeat fabric of a pulp needs to be removed. To prevent development of periapical abscess, special treatment which nature depends on whether the channel was completely created is necessary.
Dislocations of teeth. Often when force of blow is not so big to cause a change, there is tooth dislocation. Usually it is followed by a rupture of a cortical plate of an alveolar bone. Blood supply of the damaged part of a bone almost is never broken, and during 3 — 4 weeks there comes full healing. On the other hand, as the alveolar edge is a support for teeth, at blow the top of a fang can be beaten out from the bed; at the same time the vessels and nerves of a pulp leaving through a small apical opening are broken off. Dislocated teeth need to be repozirovat and shinirovat urgently. If within a week sensitivity to hot and cold is not recovered, it means that tooth lifeless; sealing of a root canal with the purpose to prevent development of abscess is in that case shown.
The beaten-out teeth. Completely beaten out teeth it is necessary to reimplantirovat directly on site incidents. If it is impossible, then teeth need to be placed in saline solution or milk and to immediately bring the victim to the stomatologist for their reimplantation. Usually pulpless tooth is densely attached, but only for limited term (within 6 — 12). The injury of a periodontium conducts to an osteoklastichesky resorption of a surface of roots that breaks their communication with an alveolar bone. Nevertheless it is necessary to tell that reimplantation increases efficiency, the prosthetics which is carried out further, providing normal development of adjacent tooth structures.
Addictions. Positions of teeth substantially define a contour of an alveolar arch and a shape of a face and in turn depend on balance of forces operating on them. Normal pressure upon teeth of language is resisted by pressure of lips and cheeks; pressure upon gingivas when chewing is opposite to force of a prorezyvaniye. Disturbance of balance of these forces can change positions of teeth, affect a relative positioning of jaws and eventually a shape of a face.
Language counter-pressure. During wakefulness the deglutitory movements happen approximately each 2 min. If at the same time language moves forward, but not to the upper sky, there is almost constant pressure of language upon teeth. As a result cutters can be pushed forward that leads to development of an open bite with the acting upper lip. At this habit preload of lips at the time of swallowing is often observed. For disposal of it it is useful to use special adaptation with the safety signaling block placed on the upper sky. Besides, exercises for language under the leadership of the doctor-logopedist are effective.
Suction of fingers. Between meals children often suck fingers or a pacifier - "baby's dummy". At many this habit remains for many years, is frequent as reaction to stressful situations. It is usually easier to disaccustom to a pacifier, than to suction of fingers. The directed knaruzh pushes, especially at suction of a thumb, can reject milk cutters forward and respectively displace all alveolar arch. Constant cutters are also cut through rejected forward and if the child continues to suck fingers, forever remain in a condition of a protrusion. To warn the shift of second teeth, it is necessary to disaccustom the child to this habit.
After 4 flyings the child under the influence of adults is already capable to control the habits. The pediatrician and the stomatologist can convince the child to stop sucking fingers. If the habit is very strong, it is necessary to use the special adaptation placed in the area of front part of the sky. This adaptation prevents the child to create vacuum in an oral cavity and therefore the sucking habit dies away. At night pases an elbow joint apply an elastic bandage that sometimes yields a positive take. Difficult emotional experiences in the course of an otucheniye arise at the child only in far come cases.