Why there is caries of teeth whether it is possible to stop process?
the Mineral basis of teeth make isomorphic crystals of apatites, is basic of which gidroksilapatit Sa10(ro4)) 6(OH)2.
In an enamel layer each crystal is covered with a hydrate layer about 1 nanometer thick. Asymmetry of surfaces of crystals of a gidroksilapatit of enamel from - for unbalances of their blankets leads to emergence of excess energy. Its existence is the reason of adsorption of a hydrate layer with being in is mute ions of minerals which neutralize charges of surfaces of crystals. Thus, penetration of substances on a surface or in crystals of enamel is connected with overcoming by ions of hydrate covers.
of the Time of enamel reach 2,5 nanometers, length - from 0,1 to 1,7 mm. Occupying from 3 to 6% of volume of enamel in inside layers. In external - from 0,1 to 0,8%. Diffusion of ions of hydrogen (protons), H+ happens in the direction with - axes of crystals. Proton conductivity increases conductivity of ions of minerals in enamel several times. The sizes and volume of a time in enamel considerably influence its permeability as limit receipt in enamel of large molecules. It is known that ionic radiuses of usual minerals fluctuate within 0,15 - 0,18 nanometers.
Thus, enamel of tooth represents the molecular filter. Organic substances give enamels of property of a semipermeable membrane. At initial stages of caries permeability of enamel near the place of defeat increases. At the same time both the sizes, and amount of a time in enamel (from 7 to 250 times) significantly increase, reaching 25% to an obja - ma.
Subsurface demineralization of layers of enamel is a pathogenetic basis of emergence of carious process. By researches of many authors it is proved that process of a mineralization of enamel comes owing to receipt of minerals from saliva. Processes of demineralization and mineralization of enamel is an essence, bases of development and knocking over of carious process. Feature and unity of processes - and re-mineralizations is that they happen continuously, being in dynamic balance in systems oral liquid - enamel. These processes cause that minimum level of intake of mineral substances which is found in solid tissues of teeth at early stages of development of caries.
the mathematical model of processes of demineralization Offered by authors at an early stage of development of caries considers dependence the speed of demineralization and coefficient of diffusion of H+ from oral liquid, from porosity of the enamel increasing by 30 - 60 times in a gradient from enamel blankets to a dentine. Therefore, according to authors, the maximum speed of reaction of demineralization in deep layers can surpass similar process in enamel blankets more than twice. Authors explain with this feature of course of processes defeat of layers of enamel under its surface at an early stage of caries.
the Mineral component of a dentine makes about 70%, and 30% are the share of organic compounds and water. The dentine tubes representing themselves ideal capillaries begin from internal surfaces of a layer of the dentine adjoining a pulp reach to dentinno - enamel border.
System of tubes of a dentine is focused out of communication with power lines of chewing loadings. On okklyuzionny surfaces of teeth they are located parallel to power lines. In areas of ekvator - at an acute angle, and in areas of root parts - it is perpendicular to power lines. Dentinny tubes - from a pulp to enamel and cement are directed. Tubes settle down radially in the direction of the shortest distance between a dentine and enamel.
Width of dentinny tubes about 5 mk at dentinno - pulpovy border. Tubes are narrowed in the direction emalevo - dentiny border to 1 mk. Closer to dentinno - enamel border of a tube branch and anastomozirut among themselves. Directly at a dentine - enamel border each tube forks. Density of an arrangement of tubes corresponds to the volume and the importance of the loading which is carried out by teeth.
the Greatest density of tubes, about 75 thousand on square millimeter is noted in koronkovy parts in areas of hillocks, in root parts density of tubes is 3 - 4 times less. The metabolism of a pulp is directed knaruzh through dentine tubes. Existence of an ionic exchange between the blood circulating in a pulp, and tubes of a dentine it is shown on the patients suffering from an argiriya. At an argiriya the stroked salts of silver are laid in fabrics, painting them in black color. At microscopic research of tissues of teeth painful with an argiriya, salts of silver find out both in odontoblasta, and in dentinny tubes what gives to teeth a gray shade. Besides, it is known that reception of antibiotics of a tetracycline row, is the reason of coloring of a dentine in yellow shades.
the tooth Pulp - represents soyedinitelnotkanny education. The main cages of a pulp are the fibroblasta similar to the cages of the same name located in other bodies. Odontoblasta are the high-differentiated pulp cages, developing a dentine. In koronkovy part of a pulp of an odontoblasta develop a normal dentine with normal dentinny tubes in root part closer to a top, - develop a dentine more amorphous with smaller quantity of tubes. On border with predentiny odontoblasta settle down a layer from 6 - 8 cages adjoining among themselves. Each shoot of an odontoblast occupies a separate tube in the main substance of a dentine, filling its gleam. Several shoots of the odontoblast called still by Thomson`s fibers in one tube are in certain cases noted. Behind a layer of odontoblast in koronkovy part of a pulp the zone, free from cages, called by Veyl`s layer settles down. Which contains nervous elements. In middle and top parts of a pulp of acellular zones it is not noted. Behind Veyl`s zone the zone rich with cages, presented by fibroblasta and undifferentiated mesenchymal cages which are capable to be differentiated in odontoblastopodobny cages at damage of odontoblast settles down.
the Main substance of a pulp consists a protein in combination with glycoproteins and mucopolysaccharides. Like the main substance in other body organs. The metabolism in cages and fibers of a pulp passes through the main substance presented by the viscous liquid described by M. B. Engel/1958 / as “the internal environment of a pulp“ through which there pass metabolites from arteriol in prekapillyara and further in capillaries to cages and metabolism products are brought out of cages in venulyarny capillaries. Internal diameter arteriol about 50 mk, capillaries 7 mk, the wall of a capillary has thickness no more than 0,5 and is the semipermeable membrane providing an exchange of liquids. According to laws of hydrostatic and osmotic pressure nutritious solution moves from capillaries to cages. The distance between a capillary and a cage does not exceed 50 mk.
Receipt of metabolites from arteriolyarny capillaries in pulp cages, occurs only after their dissolution in the main substance of a pulp. Removal of products of a metabolism is carried out similarly, after preliminary dissolution in the main substance before receipt in venous capillaries.
Thus, becomes clear influence of change of physical indicators of viscosity of density, a water surface tension and acceleration of gravity on the main substance of a pulp, and, thus, on intensity of processes of a metabolism in a pulp, its viability.
of the Hydrodynamics engineer of tooth - an alveolar segment of the person is the copy of hydrodynamics of all organism. The pulp of tooth and a dentine is a uniform soyedinitelnotkanny complex. The dentine tubes representing ideal capillaries with a diameter from 2 to 5 and up to several thousand microns long (from 0,1 to 3 - 5 mm), are filled with dentinny liquid. Dentinny liquid on structure is similar interstitsionalny, it is updated ten times within a day due to receipts from a pulp. Its quantity corresponds to 0,01 ml on 1 gram of tissue of tooth. The tubule of a dentine connects each cage odontoblast interfaced to the free nervous termination and, forming a difficult receptor of pain, with topographical is remote - ny by loci of enamel and a dentine. Dentinny liquid owing to positive a capillary - the awn called by tooth pump - the tooth pump, permanently moves through dentine tubes in the centrifugal direction with a constant speed of 2 - 3 mm / page. Filters between enamel prisms on its surface in the form of krevikulyarny liquid.
As soon as this process is slowed down to a surface of enamel the microbic cage forming a colony which is calcinated outside adgezirutsya. There is a microbic plaque. Due to the deuterium oxide accumulation in tubules of a dentine there is “a subsurface demineralization of enamel“, break of microorganisms in a gleam of dentinny tubules: infection of contents of tubules and development of caries.