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What does the remineralization of enamel teeth?
08-09-2009
To save resistant to caries tooth enamel requires an effective means of influencing it.
In the crystal lattice of biological apatites are vacancies and defects – absence of an atom or columns of atoms, called dislocations. Sometimes in the crystal there is only one column of atoms without any of the crystal lattice, which is the reason for the rapid penetration of acids along the axis of the crystal – a speed of 500 angstroms / sec.
For the crystallization processes in enamel is important and its organic matrix, which includes the calcium-binding protein that is necessary for nucleation and crystal growth regulation as well as variations of concentration of fluoride ions in the fluid surrounding enamel.
The surface layer of enamel is different from the more profound mineralization, density, microhardness, resistance to decay, a higher content of trace elements, including fluoride. The surface layer of enamel exposed to less acid than its internal parts.
When decalcification of enamel caused by the attack of organic acids, is changing the shape, size and orientation of hydroxyapatite crystals.
In the initial stages of the caries disease process, mainly concentrated in the surface layers of enamel, which causes a change in its physical and chemical properties, resulting in a carious white spot appears.
The degree of demineralization of enamel in caries depends on the concentration gradients of neutral complexes of calcium, phosphorus, fluoride and organic acids on the structure and chemical composition of enamel.
Less than stand with those compounds demineralization of enamel, which in chemical composition and structure differ from hydroxy apatite.
The surface layer of enamel in this area relatively preserved, that is probably associated with differences in chemical composition of surface and subsurface enamel, the collection of mineral components from both the oral fluid, and from the subsurface damage. On the surface carious spots formed amorphous protective film. Of the damaged section of the subsurface is a loss of calcium, phosphorus, magnesium, carbonate, decreases the density of enamel, it raises its solubility.
With the formation of focal demineralization occurs mainly decalcification. During the ion exchange hydrogen ions to a certain limit may be absorbed by the enamel without destroying its structure, but it decreases the value of Ca / P ratio. Thus, enamel is a kind of buffer system to acids, acting on its surface. It is important that this process is reversible, and under favorable conditions in the mouth or under the influence Remineralizing liquid calcium ions can enter the crystal lattice, displacing hydrogen ions.
When caries significantly reduced the calcium content in the horn of the liquid, which lowers the speed of its revenues in the enamel and supports the shift of dynamic equilibrium at the boundary of the liquid-oral enamel demineralization in the direction of the process. Dental caries in the stage of the spot – an opportune time for remineralization, as the organic matrix of enamel is preserved and can serve as nucleation centers for crystal growth. At the same time, because this process involves calcium ions, demineralization of enamel can cause such physical and chemical changes, which, to ¬ nechnom run, lead to proteolysis of organic matrix.
For successful treatment of focal demineralization of enamel used drugs that compensate for defects in the crystal lattice, increases the resistance of enamel to acids, reduce its permeability.
Remineralizsaschya – partial restoration of the density of the damaged enamel, which is similar to the mineralization of immature teeth. The difference between them is the same that in the first case due to prior caries attacks diffusion channels are filled with minerals coming from the subsurface layer. The result is the impossibility of penetration of ions from Remineralizing solutions in the deep layers of enamel and gipomineralizovannye area, whereas during the maturation of teeth after the eruption, this process occurs.
Diffusion in the enamel of calcium ions, phosphate and fluoride has its own characteristics, which may be due to differences in the surface potential of the outer enamel or in charge of the ions of calcium and phosphate.
The impact on the chemical composition of tooth enamel, it is important both during the bookmarks, development and mineralization of teeth, and during the eruption and maturation of enamel. Given the timing of eruption Remineralizing therapy advisable to start with 6 years of age, thus enhancing resistance of enamel, with the first stage of this process should be enriched ¬ schenie enamel calcium and phosphate with the subsequent introduction ¬ eat fluoride preparations, which reduce the permeability of enamel.
Under natural conditions, a source of calcium, phosphorus and fgoridov enamel is oral fluid, which is oversaturated with respect to almost all forms of calcium phosphate. Mature enamel can absorb fluoride, even in such low concentrations, which are present in oral fluid. Remineralizing potential of saliva can stop cavities in the stage of white spots in 50% of cases. Therefore necessary to resort to the action of various Remineralizing funds that would not only make available or appearing during carious attack defects in the crystal lattice of enamel, but also increase its resistance.
According to most researchers, Remineralizing preparations should include various ve ¬ ety, and increases the resistance of enamel: calcium, phosphorus, fluoride, strontium, zinc, etc.
Strengths caries properties are fluorine, phosphorus, to cariogenic substances include selenium, cadmium, magnesium, lead (Navia, 1972).
Important role in the remineralization of enamel attached phosphorus drugs, which increase the ion-selective properties of enamel, alter its adsorption capacity, favoring the admission of fluoride in enamel. It is believed that the remineralization solutions with a concentration of 1 mM calcium stimulated mainly the growth of crystals, but with a concentration of 3 mM is in addition to the growth and nucleation, which limits the size of the crystals and reduces clogging micro space surface layer that prevents remineralization in the deeper layers.
The effectiveness of remineralization can be judged by stabilization or disappearance of white spot enamel caries increment reduction. Under the influence of these drugs is an intensive formation of crystals of calcium fluoride varying degrees of crystallization and shape, thus generating a film thickness in fractions of a micrometer, is covered lation entire area of focal demineralization and very firmly bound to the matrix of enamel. It is believed that the remineralization occurs not structural, and sorption relationship of calcium, which may further serve as a source of income for Ca ions in the crystal lattice defects apatite demineralized enamel.
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