RU2538648C2 - Formulation for retrograde filling of root canals - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to dentistry. A formulation for retrograde filling of root canals contains calcium oxide, aluminium oxide and silicone oxide, each of which is prepared by separate baking, processing and functional additives, and an X-ray contrast extender - zirconium oxide. The processing additive contains plasticising and water-retaining ingredients in the form of compounds of cellulose and/or its esters and/or polysorbates, as well as whitening inert ingredients in the form of titanium dioxide. As the functional additive, the formulation contains bactericidal ingredients of dioxidine, and/or metronidazole, and/or silver, and/or copper-calcium hydroxide, and anti-inflammatory ingredients in the form of glucocorticosteroids specified in hydrocortisone acetate and/or dexamethasone. The formulation can additionally contain calcium salts.

EFFECT: combination of the ingredients of the formulation in certain quantitative content provides a high prolonged alkalinity of the material of approximately pH 12, a flow characteristic of the material of 25-26 mm used to fill the root canal tightly, a setting time of the material within 10-20 minutes controlled by a dentist in the mouth cavity, an after-setting higher compression strength of not less than 40 MPa, a lower solubility of the material of no more than 1,5% and a high radio density of the material.

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Description

The present invention relates to medicine, namely to dentistry, and can be used for retrograde filling of the root canals of the teeth, for filling the apical part of the canal with incomplete root formation, for closing perforations (bi- and trifurcations) of the root canal, and also as a medical coating pulps in the treatment of deep caries and pulpitis.

It is known that with inadequate treatment of caries, complications often occur (pulpitis, periodontitis), leading to the need for surgical treatment to preserve the tooth. This applies to such complications as perforation and poor-quality filling of the root canals of the teeth, when it is impossible to eliminate these complications endodontically. In such situations, the problem arises of the choice of filling materials and tools for obstructing perforations and high-quality retrograde root canal filling. The materials used for these purposes must meet a number of requirements: to have biocompatibility to surrounding tissues, not to dissolve, to have good adhesion to cement of the root of the tooth in a humid environment, and most importantly, to prevent the "leakage" of microorganisms and their decay products into periapical tissues.

From the previous technical level it is known that long-term use for retrograde filling of zinc oxide-eugenol cements. Retrograde fillings with zinc oxide-eugenol have a significantly higher success rate than amalgam and show high biocompatibility, have low solubility, good antibacterial action with minimal leakage of dye. The disadvantage of these materials is the presence of giant neoplasm cells on the surface of the material of the retrograde filling [Geurtsen W (2000) Biocompatibility of resin-modified filling materials. Critical Reviews of Oral Biology and Medicine 11, 333-355].

Also known material Diaket (ESPE-Premier, Norristown, PA, USA), kneaded for retrograde filling to a thicker consistency than when used as an intra-root sealer. The healing of periradicular tissues was generally considered favorable. In addition, Diaket provides better sealing than IRM or EBA for retrograde preparation of both 1 and 3 mm. The disadvantage is the fragility of the retrograde filling [www.dental-revue.ru/index.php?page=03&subPage=02&artId=15&artNum=2].

When using glass ionomer cements (SIC) as the material for retrograde filling, the antibacterial effect of the SIC is unstable. This becomes especially significant when glass ionomers are used as materials for closing root perforations and are in contact with the periodontium for a long period of time. The disadvantage of materials from SIC is their low sealing ability [Mickel AK, Wright ER (1999) Growth inhibition of Streptococcus anginosus (milleri) by three calcium hydroxide sealers and one zinc oxide-eugenol sealer. Journal of Endodontics 25, 34-37].

It is known that amalgam is most widely used as a material for retrograde filling for many years. This is mainly due to the fact that dentists are well acquainted with the technique of working with amalgam, and, in addition, amalgam is highly radiopaque. The continued use of amalgam today is being called into question for reasons such as micro-leakage, biocompatibility, corrosion, staining and the harmful effects of mercury in general. It has been proven that the tissue response to retrograde amalgam filling is unfavorable and associated with inflammation, which is established in short-term studies covering the period from 2 weeks to 5 months after filling. Histological staining of mercury proves the presence of traces of amalgam in the tissue at some distance from the root apex. Retrograde amalgam filling is associated with the most severe and extensive inflammation compared to all tested materials. Amalgam has significant disadvantages: a complex technique of use, the need for absolute dryness of the surface to be sealed. Filling the cavity can be accompanied by the ingress of amalgam into the tissue. Tissue pigmentation may occur in the form of gum darkening, which violates aesthetics, especially in the frontal area [Cohen BI, Pagnillo MK, Musikant BL, Deutsch AS (2000) An in vitro study of the cytotoxicity of two root canal sealers. Journal of Endodontics 26, 228-229].

Traditional composites containing a polymerizable organic matrix, inorganic reinforcing fillers, and a silane coupling agent that combines organic and inorganic components were also used as materials for retrograde filling. The organic matrix consists of several mono-, di- and oligomers (for example, Bis-GMA, UDMA, EGDMA, TEGDMA, etc.) and various additives that function as initiators, stabilizers or inhibitors [Pitt Ford TR, Torabinejad M , Abedi HR, Bakland LK, Kariyawasam SP (1996) Mineral trioxide aggregate as a pulp capping material. Journal of the American Dental Association 127, 491-494]. Various factors determine the low biocompatibility of the composite material, especially the amount and nature of alkalized components. Several composites have been found to be capable of releasing formaldehyde in quantities sufficient to cause necrosis or local allergic reactions.

Known material for filling the root canals of the teeth [RF patent No. 2197940 for the invention], containing cement in the amount of 30-70% by weight of the powder, which includes dicalcium and tricalcium silicate, tricalcium aluminate, F and P and surfactants (surfactants ), a radiopaque filler (barium sulfate) in an amount of 15-25% by weight of the powder, a moderator (slowing down the solidification time of the filling material) in an amount of 10-30% by weight of the powder. The components are mixed in a liquid consisting of water, a surfactant and a plasticizer. The components are taken in a certain quantitative ratio: a bactericidal surfactant in an amount of 0.05-2.5% by weight of a liquid, a plasticizer in an amount of 10-60% by weight of a liquid, water in an amount of 40-90%. The mass ratio of the powder: liquid is 2.0-3.0: 1. The invention provides a filling material with high permeability, adhesion to dentin, low leachability, high strength, long-term bactericidal activity. The material provides remineralization of the hard tissues of the tooth root.

The disadvantage of the material is insufficient strength (14-15 MPa after 24 days of hardening in wet conditions), a high plasticizer content in the matrix, which increases the solubility of the material and reduces the tightness and long-term root filling.

Mineral trioxide aggregate (MTA ProRoot, Dentsply, USA), which was proposed as a material for retrograde filling of the root canals of the teeth, as a mixture for sealing the communication path between the root canal system and periapical tissues, was chosen as the closest in combination of essential features. The material contains: 75% Portland cement, including oxides of silicon, calcium and aluminum, 5% gypsum and 20% of the radiopaque ingredient - bismuth oxide [catalog of the company ″ Tulsa Dentsply Ltd ″, USA, 2011]. The material is less permeable than amalgam or zinc oxide-eugenol materials in leakage tests. Animal studies have demonstrated its good biocompatibility. The use of MTA as a material for retrograde filling provided good results with significantly less periradicular inflammation compared to the amalgam and the emergence of a new cement layer on top of the retrograde filling in all long-term samples [Torabinejad M, Pitt Ford TR, McKendry DJ, Abedi HR, Miller DA, Kariyawasam SP (1997) Histologic assessment of mineral trioxide aggregate as a root-end filling in monkeys. Journal of Endodontics 23, 225-8]. Clinical studies have shown that MTA may have clinical advantages over other sealers, such as calcium hydroxide based materials, in the treatment of complex endodontic problems, such as root fractures and perforations. MTA is also used as a material for isolating the pulp during its mechanical opening, to stimulate the formation of the apex of the root, to close the perforation of the root, and also as a barrier for intracanal whitening of endodontically treated teeth [Grigoryants LA, Vadalyan VA, Grigoryants A .G. Use of new technologies and MTA filling material in surgical endodontics. Dentsply News (2004) No. 4]. The principle of the chemical compound in MTA is based on tricalcium oxide, tricalcium aluminate, tricalcium silicon and silicic acid. The powder contains hydrophilic particles, which in the presence of moisture or blood form a colloidal gel, creating an impenetrable barrier. The drug consists of powder and capsules of distilled water. In connection with a one-time powder packaging, sterility of the material and accurate dosage of the powder are ensured. The material is radiopaque. The cost of packaging (5 g) is 11750 rubles. Manufacturer: Dentsply (www.aldera.ru/show_items.php?iditem=1592&iddiv=4).

The disadvantages of the material are due to its performance characteristics: it is difficult to dose the amount of liquid when mixing the drug and placing it in the root canal; the drug has low fluidity, is non-ductile and not dense, which creates difficulties when packing the filling mass; it is impossible to treat the bone cavity with liquid without rinsing the drug; curing time is from 2 to 4 hours. The use of Portland cement in the form of a finished component of constant composition does not make it possible to change the ratio of chemically pure components of the composition with controlled properties typical of dental materials. The high cost of the material does not allow its use in medical municipal institutions.

The objective of the invention is the creation of a water-soluble material based on chemically pure components with universal properties for retrograde filling of the root canals, for filling the apical part of the canal with incomplete root formation, for closing perforations (bi- and trifurcations) of the root canal, for use as a therapeutic coating pulps in the treatment of deep caries and pulpitis, as well as expanding the arsenal of calcium-containing materials similar in purpose, reducing cost awn material and improving its quality.

Technical results that can be obtained by implementing the invention are:

- the implementation of the appointment of a chemical purity composition with controlled properties for retrograde filling of the root canals of the teeth;

- high prolonged alkalinity of the material of the order of pH 12;

- increased fluidity of the material within 25-26 mm with the possibility of hermetically filling the root canal;

- controlled by the dentist curing time of the material within 10-20 minutes in the oral cavity;

- increased compressive strength of cement stone at least 40 MPa;

- a decrease in the solubility of the material after curing to a value of not more than 3.0%;

- enhanced radiopacity of the material.

The solution to the problem and the achievement of the above results became possible due to the fact that the composition for retrograde filling of the root canals of the teeth, including calcium, silicon, aluminum and X-ray filler, characterized in that it contains calcium oxide powder with a basic substance content of 98.0%, obtained by firing clay with lime and magnesium oxide in a weight ratio of 0.1: 9.8: 0.1, silica powder with a basic substance content of 98.5%, obtained by burning clay with lime in a weight ratio of 9, 9: 0.1, and an alumina powder with a basic substance content of 99.5%, obtained by burning clay with aluminum oxide in a weight ratio of 0.1: 9.9, additionally contains a technological and functional additive, while the technological additive includes plasticizing and water-retaining ingredients in the form of compounds from the range of cellulose and / or its esters and / or polysorbates, as well as whitening inert ingredients in the form of titanium dioxide, as a functional additive, the composition contains bactericidal ingredients from the series of dioxidine, and / or metronidazole and / or silver and / or copper-calcium hydroxide and anti-inflammatory ingredients in the form of glucocorticosteroids selected from hydrocortisone acetate and / or dexamethasone, and zirconia as the radiopaque filler, in the following ratio of ingredients in wt.% :

Calcium Oxide Powder Containing 98.0% calcium oxide and 1.0% magnesium oxide, based on the content of the main component 20.0-50.0 Alumina powder based on the content of the main component 10.0-30.0 Silica powder based on the content of the main component 5.0-40.0 Technological Additive: - plasticizing and water-retaining ingredients in the form of compounds from the range of cellulose and / or its esters, and / or polysorbates, 0.2-3.0 inert whitening ingredient in the form of titanium dioxide 0.3-2.0 Functional Additive: - bactericidal ingredients from a number of dioxidine, and / or metronidazole and / or silver, and / or copper-calcium hydroxides 0.005-2.0 - anti-inflammatory ingredients in the form of glucocorticosteroids selected from hydrocortisone acetate and / or dexamethasone 0.005-1.0 X-ray contrast filler: - zirconium oxide rest

In a particular example, the composition for retrograde filling of the root canals of the teeth as part of the processing aid additionally contains calcium salts in an amount of 0.1-4.5 wt.%.

An inventive step is that calcium, silicon, and aluminum oxides are obtained by calcining each component separately to give them a certain activity without introducing additional ingredients - curing regulators (accelerators or moderators) and controlled purity of the initial components and the curing product. The plasticizer is introduced into the powder part in the ratio necessary to obtain, when the composition is mixed with distilled water, a plastic, highly fluid paste, convenient to use (without additional devices) during the working time of 5-7 minutes at 18-23 ° C and hardening under the supervision of a dentist for 10-20 minutes in oral conditions at 37 ° C. During curing, calcium oxide interacts with distilled water and turns into calcium hydroxide, which provides high alkalinity of the material (pH 12), which effectively and quickly suppresses the bacterial microflora of the root canal. Amorphous calcium hydroxide then reacts with the active oxides of silicon and aluminum. Hydrate neoplasms quickly appear on the surface of particles of silicon and aluminum oxides (studies by Locher et al.), Creating screening films that almost completely stop the interaction with water. There is an induction period (dormancy), which determines the working time of the composition. Then there is a sharp formation of calcium hydroaluminosilicate, leading to the hardening of the structure and obtaining in a short time a strong matrix. The resulting white cement does not change the color of tooth tissues and does not require additional components in the form of bleaches. Cement has an initial high alkalinity, which determines its bactericidal activity. Calcium hydroxide formed upon mixing with water stimulates the processes of apexogenesis, stops bone resorption, stimulates the formation of secondary dentin, has low solubility and high mechanical strength. Zirconium oxide was introduced into the composition as a bioinert filler to ensure high radiopacity of the material to control the filling of narrow root canals by x-ray. Prolonged bactericidal action of cement is provided by the introduction of bactericidal components that do not reduce their activity in the presence of blood in the form of powdered substances: dioxidine, and / or metronidazole, and / or powdered silver and / or copper-calcium hydroxide. Post-filling pains and allergic reactions are reduced with the help of the introduced anti-inflammatory components in the form of hydrocortisone acetate and / or dexamethasone in combination with the main components that provide high clinical results. The plasticizer in the form of cellulose and / or its esters of viscosity - from 2000 to 100000 cP and / or polysorbates provides the plasticity and fluidity of the obtained cement paste, which contributes to a dense and reliable obstruction of the root canal and its tightness over time. After hardening, cement has a positive effect on the regeneration of tooth hard tissues. The introduction of bactericidal and anti-inflammatory ingredients together with a plasticizer and a radiopaque filler give the main components that form cement the necessary properties that meet the requirements of GOST R 51059-97.

The claimed combination of all properties and the ratio of the components of the composition made it possible to achieve synergy and obtain a material with high purity and unique properties and a wide range of indications: for retrograde filling of the root canals of the teeth, for filling the apical part of the canal with incomplete root formation, for closing perforations (bi- and trifurcations ) the root canal and as a therapeutic coating for pulp in the treatment of deep caries and pulpitis.

To prepare the inventive composition for retrograde filling the root canals of the teeth, the clay is fired with lime and magnesium oxide and the frit is ground. A finely ground clay-alumina mixture is fused separately and ground. Separately, the clay-lime mixture is fused and the sintering product is ground. At various ratios of the obtained intermediates, a different ratio of powders of calcium, silicon, and aluminum oxides is obtained. A radiopaque filler, functional and technological additives (pre-crushed and sieved through a nylon sieve with a mesh size of 50 μm) are introduced into the mixture. The technological additive includes plasticizing and water-retaining ingredients in the form of compounds from a number of cellulose and / or its esters and / or glycols, polysorbates and an inert bleaching additive in the form of titanium dioxide and / or zinc oxide, as a functional additive, water-soluble material contains bactericidal and anti-inflammatory ingredients from the range of dioxidine and / or metronidazole, and / or silver and / or copper-calcium hydroxide, and / or miramistin, and / or cetrimide and glucocorticosteroids in the form of hydrocortisone acetate and / or eksametazona. The mixture of components is thoroughly mixed in a ceramic drum with ceramic grinding bodies in a roller mill for 1 hour. The resulting composition is metered into sealed foil and polyethylene bags, which are sealed with a special device.

All components were taken in the declared quantitative ratios.

After preparation, the material is a finely ground white powder, dosed at 0.5 g in sealed sealed bags. When mixing the powder with distilled water in a weight ratio of 3: 1, the composition in the cement test stage is obtained in the form of a plastic paste (the pH value of pH is not less than 12 for universal indicator paper) with a fluidity of 25-26 mm (normal: not less than 20 mm ), a film thickness of 40 microns (normal: not more than 50 microns). The working time of the material is 4-7 minutes (norm: at least 1.5 minutes), the hardening time is 10-15 minutes, the compressive strength is 40-45 MPa, the radiopacity is equivalent to the radiopacity of an aluminum wedge with a layer of 4-6 mm (norm: not less than 3 mm). The indicators were determined according to the methods of GOST R 51059-97 [Dental materials for filling the root canals of the teeth. General technical requirements. Test methods] and GOST R 51744-2001 [Water-based dental cements. Technical requirements. Test methods].

Practical applicability is shown in the following examples of specific performance.

Example No. 1. To prepare the claimed composition for retrograde filling of the root canals of the teeth, the clay was calcined with lime and magnesium oxide in a weight ratio of 0.1: 9.8: 0.1 in a muffle furnace at a temperature of 1000 ° C for 1 hour and ground in portions in a planetary mill to particle size of 50 microns. Received a powder of calcium oxide with a basic substance content of 98.0% and impurities: aluminum oxide - 0.5%, silicon oxide - 0.5%, magnesium oxide - 1.0%. Separately, a finely ground clay-alumina mixture was fused in a weight ratio of 0.1: 9.9 at a temperature of 1200 ° C for 1 hour and ground to a particle size of 50 μm. An alumina powder was obtained with a basic substance content of 99.5% and impurities: silica - 0.5%. Separately fused a finely ground mixture of clay and lime, taken in a weight ratio of 9.9: 0.1, in a muffle furnace at a temperature of 1000 ° C for 1 hour and ground in portions in a planetary mill to a particle size of 50 μm. Silicon oxide powder was obtained with a basic substance content of 98.5% and impurities: calcium oxide - 1.0%, aluminum oxide - 0.5%. A mixture of powders was prepared according to the content of the main components. Dioxidine, dexamethasone, methylcellulose, titanium oxide and zirconium oxide as an X-ray contrast filler were sprinkled with the resulting mixture as technological and functional additives. The mixture of components was thoroughly mixed in a ceramic drum with ceramic grinding bodies in a roller mill for 1 hour and the composition of the following content of ingredients was obtained, wt.%:

Calcium Oxide Powder Containing 98.0% calcium oxide and 1.0% magnesium oxide, based on the content of the main component 20,0 Alumina powder based on the content of the main component 10.0 Silica powder based on the content of the main component 5,0 Technological Additive: - methyl cellulose 0.2 - titanium dioxide 0.3 Functional Additive: - dioxidine 0.005 - dexamethasone 0.005 X-ray contrast filler: - zirconium oxide 64.49

To obtain a cement paste, the composition is mixed with distilled water in a ratio of 3: 1 and a cement mass with the characteristics:

- working time, min 7.0 - hardening time, min 12 - fluidity, mm 26 - the value of the hydrogen index, units pH 12 - film thickness, microns 40 - radiopacity, mm 6 - compressive strength, MPa 41 - solubility,% 2,5

The resulting composition for retrograde filling of the root canals has sufficient working time, good fluidity, high radiopacity, optimal values of hardening time, film thickness and solubility.

Example No. 2. The preparation of the composition for retrograde filling of the root canals of the teeth is performed according to example No. 1, but differs in that the content of the components in the composition for retrograde filling of the root canals of the teeth corresponds to the following composition, wt.%:

Calcium Oxide Powder Containing 98.0% calcium oxide and 1.0% magnesium oxide, based on the content of the main component 15.0 Alumina powder based on the content of the main component 0.5 Silica powder based on the content of the main component 3.0 Technological Additive: - methyl cellulose 0.01 - titanium dioxide 0.01 Functional Additive: - dioxidine 0.0025 - dexamethasone 0.0025 X-ray contrast filler: - zirconium oxide 81,475

In the resulting composition for retrograde filling of the root canals of the teeth, the content of powders of oxides and additives is below the minimum limit and in the minimum limit and corresponds to the maximum content of radiopaque filler. To obtain a cement paste, the composition is mixed with distilled water in a ratio of 3: 1 and a cement mass with the characteristics:

- working time, min 30,0 - hardening time, min 3600 - fluidity, mm - - the value of the hydrogen index, units pH 9 - film thickness, microns 45 - radiopacity, mm 8 - compressive strength, MPa 5 - solubility,% 10.5

The resulting composition for retrograde filling of the root canals of the teeth with a long working time and hardening time has a high radiopacity, but insufficient alkalinity, low strength after curing and high solubility.

Example No. 3. The preparation of the composition for retrograde filling of the root canals of the teeth is carried out according to example No. 1, but differs in that polysorbate-80 and titanium dioxide are introduced as a technological additive, as well as an additional calcium salt in the form of semi-aqueous calcium sulfate and powdered silver is introduced as a bactericidal component, as a component that reduces pain reactions, dexamethasone and hydrocortisone are introduced, and the ratio of ingredients in the composition for retrograde filling of the root canals of the teeth corresponds to the average th value stated limits, mass.%:

Calcium Oxide Powder 35.0 Alumina powder 20,0 Silica powder 10.0 Technological Additive: - polysorbate-80 0.5 - titanium dioxide 1.65 - calcium sulfate semi-aquatic 3.0 Functional Additive: - silver powder 0.5 - dexamethasone 0.25 - hydrocortisone acetate 0.25 X-ray contrast filler: - zirconium oxide 28.85

To obtain a cement paste, the composition is mixed with distilled water in a ratio of 3: 1 and a cement mass with the characteristics:

- working time, min 5,0 - hardening time, min fifteen - fluidity, mm 25 - the value of the hydrogen index, units pH 12 - film thickness, microns 43 - radiopacity, mm four - compressive strength, MPa 44 - solubility,% 1.3

The resulting mass on the basis of the composition for retrograde filling of the root canals of the teeth is a plastic paste that is easily introduced into the root canal of the tooth using a canal filler. The characteristics of the resulting mass are fully consistent with the stated standards of the technical result.

Example No. 4. The preparation of the composition for retrograde filling of the root canals of the teeth is carried out according to example No. 1, but differs in that the content of the components in the composition corresponds to the maximum amount of alumina, technological and functional additives, barium sulfate is introduced as an radiopaque filler in the following ratio of components, wt.%:

Calcium Oxide Powder 30,0 Alumina powder 30,0 Silica powder 25.0 Technological Additive: - methyl cellulose 1,0 - titanium dioxide 8.7 Functional Additive: - dioxidine 2.95 - dexamethasone 0.05 X-ray contrast filler: - barium sulfate 2,3

To obtain a cement paste, the composition is mixed with distilled water in a ratio of 3: 1 and a cement mass with the characteristics:

- working time, min 1,5 - hardening time, min 5,0 - fluidity, mm 19 - the value of the hydrogen index, units pH 12 - film thickness, microns fifty - radiopacity, mm one - compressive strength, MPa 45 - solubility,% 3.0

The resulting mass on the basis of the composition for retrograde filling of the root canals of the teeth has low fluidity, reduced hardening time, maximum allowable solubility, low radiopacity, unsatisfactory handling properties due to insufficient fluidity.

Example No. 5. The preparation of the composition for retrograde filling of the root canals of the teeth was performed according to example No. 1, but differs in that the content of calcium oxide powder is taken according to the maximum content within the claimed composition, polysorbate-40 is introduced as a plasticizing component, metronidazole is introduced as a bactericidal substance in the following ratio components, wt.%:

Calcium Oxide Powder 50,0 Alumina powder 10.0 Silica powder 10.0 Technological Additive: - polysorbate-40 4.0 - titanium dioxide 3,5 Functional Additive: - metronidazole 1,0 X-ray contrast filler: - zirconium oxide 21.5

To obtain a cement paste, the composition is mixed with distilled water in a ratio of 3: 1 and a cement mass with the characteristics:

- working time, min 10.0 - hardening time, min 20,0 - fluidity, mm 27 - the value of the hydrogen index, units pH 12 - film thickness, microns 57 - radiopacity, mm 2 - compressive strength, MPa 40 - solubility,% 4,5

The resulting mass based on the composition for retrograde filling of the root canals of the teeth has a sufficient working time, but an extended hardening time, a large film thickness and high solubility.

Example No. 6. The preparation of the composition for retrograde filling of the root canals of the teeth was carried out according to example No. 1, but differs in that the composition of the silicon oxide powder is lower than stated, and the components of the technological additive are introduced in amounts exceeding the maximum, and miramistin is introduced as a bactericidal additive, and as zinc oxide is introduced in the following ratio, wt.%:

Calcium Oxide Powder 40,0 Alumina powder 35.0 Silica powder 4.0 Technological Additive: - methyl cellulose 6.6 - zinc oxide 5,0 Functional Additive: - miramistin 2.0 X-ray contrast filler: - barium sulfate 7.4

To obtain a cement paste, the composition is mixed with distilled water in a ratio of 3: 1 and a cement mass with the characteristics:

- working time, min 30,0 - hardening time, min 360.0 - fluidity, mm 17 - the value of the hydrogen index, units pH 12 - film thickness, microns 64 - radiopacity, mm one - compressive strength, MPa 5 - solubility,% 3,5

The resulting mass on the basis of the composition for retrograde filling of the root canals of the teeth forms a paste of prolonged curing. After curing, a material of low strength with increased solubility and low radiopacity is obtained.

Example No. 7. Preparation of the composition for retrograde filling of the root canals of the teeth was carried out according to example No. 1, but differs in that methyl cellulose and polysorbate-80 plasticizers were introduced as a technological additive, titanium dioxide was taken, metronidazole and copper-calcium hydroxide were introduced as anti-inflammatory ingredients, as anti-inflammatory the ingredients introduced hydrocortisone acetate and dexamethasone, and the ratio of the components for the preparation of the composition corresponds to the average value of the declared limits, wt.%:

Calcium Oxide Powder 30,0 Alumina powder 15.0 Silica powder 20,0 Technological Additive: - polysorbate-80 0.3 - methyl cellulose 0.5 - titanium dioxide 1,5 Functional Additive: - metronidazole 0.5 - copper-calcium hydroxide 0.2 - hydrocortisone acetate 0.5 - dexamethasone 0.5 X-ray contrast filler: - zirconium oxide 31,0

To obtain a cement paste, the composition is mixed with distilled water in a ratio of 3: 1 and a cement mass with the characteristics:

- working time, min 5,0 - hardening time, min fourteen - fluidity, mm 26 - the value of the hydrogen index, units pH 12 - film thickness, microns 42 - radiopacity, mm four - compressive strength, MPa 44 - solubility,% 1,2

The resulting mass on the basis of the composition for retrograde filling of the root canals of the teeth has characteristics that fully comply with the stated standards of the technical result for all indicators.

Example No. 8. The preparation of the composition for retrograde filling of the root canals of the teeth was carried out according to example No. 1, but differs in that the composition contains calcium oxide powder below the stated limits, and zinc oxide is used as a whitening component, the radiopaque filler is in the form of zirconium oxide and barium sulfate, and the ratio of components for the preparation of the composition corresponds to the following composition, mass. %:

Calcium Oxide Powder 10.0 Alumina powder 20,0 Silica powder 25.0 Technological Additive: - methyl cellulose 0.5 - zinc oxide 2.9 Functional Additive: - miramistin 1,0 X-ray contrast filler: - zirconium oxide 20,0 - barium sulfate 20.6

To obtain a cement paste, the composition is mixed with distilled water in a ratio of 3: 1 and a cement mass with the characteristics:

- working time, min 10.0 - hardening time, min 60.0 - fluidity, mm 24 - the value of the hydrogen index, units pH 9 - film thickness, microns 45 - radiopacity, mm 5 - compressive strength, MPa 12 - solubility,% 5.2

The resulting mass based on the composition for retrograde filling of the root canals of the teeth is characterized by a long hardening time, low strength, high X-ray contrast, slightly alkaline reaction of the medium and high solubility.

Only when using the components in the stated ratio (examples No. 1, No. 3, No. 7) is a material obtained with high fluidity and alkalinity, sufficient working time, optimal hardening time, high strength, high x-ray contrast and low solubility. Cement dough, obtained by the compositions of the above examples No. 1, 3, 7, has excellent handling properties, is easily inserted into the root canal with the help of a root needle or canal filler, tightly seals the root system of canals, and is easily applied to hard tooth tissues as a medical-lining material. Long-term alkalinity and bactericidal properties of the components of the composition provide suppression of intracanal microflora and stimulate recovery processes.

Thus, the solution of the problem of creating a composition with universal properties for retrograde filling of the root canals of the teeth, for filling the apical part of the canal with incomplete root formation, for closing perforations (bi- and trifurcations) of the root canal, for treating the pulp in the treatment of deep caries and pulpitis resolved. The achieved result complies with the requirements for materials used in dentistry for retrograde filling of the root canals of teeth and medical materials for covering tooth pulp in the treatment of deep caries.

Claims (2)

1. The composition for retrograde filling of the root canals of the teeth, including calcium oxide, silicon, aluminum and radiopaque filler, characterized in that it contains calcium oxide powder with a basic substance content of 98.0%, obtained by calcining clay with lime and magnesium oxide in a weight ratio 0.1: 9.8: 0.1, silica powder with a basic substance content of 98.5%, obtained by calcining clay with lime in a weight ratio of 9.9: 0.1, and aluminum oxide powder with a basic substance content of 99 5% obtained by roasting hl aliens with alumina in a weight ratio of 0.1: 9.9, additionally contains technological and functional additives, while the technological additive includes plasticizing and water-retaining ingredients in the form of compounds from a number of cellulose and / or its esters and / or polysorbates, and also bleaching inert ingredients in the form of titanium dioxide, as a functional additive, the composition contains bactericidal ingredients from a number of dioxidine, and / or metronidazole, and / or silver, and / or copper-calcium hydroxide and anti-inflammatory ing edienty a glucocorticosteroid selected from hydrocortisone acetate and / or dexamethasone, and as the radiopaque filler - zirconia, with the following ratio of ingredients in mass%:.
Calcium Oxide Powder Containing 98.0% calcium oxide and 1.0% magnesium oxide, based on the content of the main component 20.0-50.0 Alumina powder based on the content of the main component 10.0-30.0 Silica powder based on the content of the main component 5.0-40.0 Technological Additive: plasticizing and water-holding ingredients in the form of compounds from the range of cellulose and / or its esters, and / or polysorbates, 0.2-3.0 inert whitening ingredient in the form of titanium dioxide 0.3-2.0 Functional Additive: dioxidine bactericidal ingredients, and / or metronidazole and / or silver, and / or copper-calcium hydroxides 0.005-2.0 anti-inflammatory ingredients in the form of glucocorticosteroids selected from hydrocortisone acetate and / or dexamethasone 0.005-1.0 X-ray contrast filler: zirconium oxide rest 2. The composition according to claim 1, characterized in that the technological additive further comprises calcium salts in an amount of 0.1-4.5 wt.%.