The ceramic foam material based on alumina, the product of the ceramic foam material (options) and the method of their manufacture

 

The invention relates to the production of ceramic foam materials and products made of ceramic foam and composite materials for medical purposes. The ceramic foam material contains not less than 98,0% by weight aluminum oxide, 0.15 to 0.4. % of magnesium oxide, not more than 0.1 wt.% silicon oxide and not more than 0.1 wt.% iron oxide has a melting point 2040oWith the average grain size of the oxide of 0.5 to 15.0 μm. Material and products produced by the refining of alumina in the aquatic environment, preparation of ceramic slurry, molding, sintering-carbonization in an oxidizing atmosphere at 1150-1250oWith and firing in an oxidizing atmosphere at 1750-1790oC. the resulting ceramic foam material and articles thereof have high quality indicators. 3 S. and 14 C.p. f-crystals, 4 Il.

THE TECHNICAL FIELD.

The invention relates to the production of ceramic foam (highly porous, cellular) and composite ceramic materials and products, namely, to obtain ceramics mainly for medical purposes for use in surgery, dentistry, oncologically, trauma, and can be used, in particular, in the manufacture of structural ceramics, endopat the tov development of bone or cartilage having a traumatic or other defects in, or damage to, or destruction of the tumor, or degenerative processes, as well as in the manufacture of various products for structural ceramics, including those used for the implementation of technologies for industrial manufacturing medical ceramics, glass, porcelain, metal alloys and other products.

THE LEVEL OF TECHNOLOGY.

Known ceramic materials based on alumina (aluminum oxide), and implants for surgery approved in 1981 the international standard ISO 6474-81 [1] having the chemical composition: Al2About3- not less than 99,5%, SiO2and alkali metal oxides is not more than 0.1%, a density of not less than 3,9 g/cm3, a bending strength of 400 MPa, the average grain size of not more than 7 μm. Data of ceramic materials and are made of these implants have the properties of a satisfactory biocompatibility and stability in the human body, so they were recommended by the International Organization for Standardization for the manufacture of joint and bone substitutes strips.

However, the physico-chemical properties of ceramic materials according to ISO 6474-81 and the known composition and technological ability, the alumina (white clay) under hydrostatic pressure and subsequent firing made from this material only massive volumetric implants (joint replacements and bone strip) relatively simple geometric shapes to replace or correct defects or deformities of massive rounded joint or skeletal bones, that did not satisfy the increasing demands on the quality of implantable ceramic materials.

In particular, one of the major drawbacks of ceramic of alumina obtained according to previously known technology, is the technical difficulty of obtaining thin-walled implants complex forms under hydrostatic pressure, decreased strength and increased shrinkage (more than 10-11%) while firing. In 1994, the international standard ISO 6474-81 (1981) was cancelled.

1994-02-01 International Organization for Standardization approved a new edition of the international standard ISO 6474, 1994-02-01 [2], where it was recommended to produce ceramic implant materials of aluminum oxide of high purity with prikalivalsa the addition of magnesium oxide for use as a bone spacers, bone substitutes and components orthopaedic joint prostheses.

The chemical composition of the material according to ISO 6474 1994-02-01: main material aluminum oxide, Al2About3high purity > 99.5%, prikalivalsa additive magnesium oxide Content of not higher than 0.3%, limits of impurities in a total amount of silicon oxide SiO2+calcium oxide Cao+oxides of alkali metals not more than 0.1%. The grain size ISO 6474 1994-02-01 for implants, used at high loads (bearing surface, substitutes joints) and for implants used at low loads (implants vernaculus-front and middle ear).

The implant material according to ISO 6474, 994-02-01 usually obtained by preparing a ceramic composition of a mixture of ultrafine exactly fractionated powder of high-purity aluminium oxide and prikalivalsa supplements in powder form of magnesium oxide, molding by pressing and sintering.

Ultra-fine alumina powder of high purity usually get plasmochemical methods and it is very expensive, and forming implants compaction method allows you to get only the thick-solid products simple geometric, often spherical or cylindrical shape. Therefore, manufactured from high-purity alumina implants roads that are inaccessible to a broad spectrum of patients and is currently in practice are mainly used only as substitutes joints massive and thick-walled implants simple geometric shapes.

Known ceramic wear-resistant, high strength, porous materials based on alumina for use in various spare parts of the EP in the textile, for manufacturing siteprovides headset; nozzles and nozzles in engineering cutting tools in the machine tool industry, containing, wt.%: the connection relating to the isomorphic class of pseudobrookite 1,0-30,0; the oxide of the divalent metal is 0.1-0.5; alumina - rest [3] . Products of this ceramic material have high strength (tensile strength in bending of at least 400 MPa); the small size of the crystals (1-2 μm); resistant to abrasion (0,1%); there was no open porosity, but they are not suitable for the manufacture of medical ceramics.

A method of obtaining corundum ceramic material intended for the manufacture of products of structural ceramics: abrasion and chemical resistant parts, can withstand high statistical load, namely, that upon receipt of the charge corundum ceramics with low sintering temperature 1500-1550oWith the used alumina (92-96 wt. %), which is mixed with pre-sintered at 900 to 1000oWith stekloduvnoe - mineralizer (3-6 wt.%) and fluoride containing additive (0.5-1 wt. %), and steklomozaika contains the components CaO, SiO2In2O3taken in the mass soraneniyu main strength characteristics at the level of structural corundum ceramics type GB-7, which is also not suitable for the manufacture of medical ceramics [4].

Therefore intensively developed different ways of getting fit for medicine corundum ceramics based on aluminum oxide, but known technology does not allow to produce acceptable quality ceramic material of the cheap and available raw materials.

Known industrial application of powder of aluminum oxide (alumina) for the manufacture of ceramic products [5]. The disadvantage of these ceramics of alumina is reduced Flexural strength (405-420 MPa), due to krupnoporistogo feedstock - alumina, which is 85% consists of particles down to 5 µm [GOST 6912.1-93. The alumina. Technical conditions], as well as the inconsistency of this material ceramic materials permitted for use in medical technology.

Known ceramic material and method for producing ceramic products based on alumina according to GOST 6912.1-93 modifying additive-containing alumina obtained by plasma-chemical method, and including these components in the following ratio, wt.%: alumina - 70,0-97,0; plasma obtained alumina - 3,0-30,0. Mixing promyshlenniki surface energy, provided activation subsequent sintering process of ceramics, which increased its density, improved strength characteristics [6]. Plasma obtained alumina produced by plasma-chemical installation in which the air stream is heated in a high frequency induction electric discharge. A hot air stream was applied to the reaction chamber in which through dispersal device was injected atomized aqueous solution of aluminium nitrate. From the drops, which received heat hot air flow, evaporated water, and the dry residue was decomposed to aluminum oxide with a particle size of 0.2-0.6 μm. The aluminum oxide was isolated from palaeohistology mixture in the vortex dust collector. When implementing this method, the aluminum oxide obtained by plasma-chemical method, was added in a predetermined ratio to the standard powder of alumina of GK mark, GOST-6912.1-93, this alumina was not less than 85% of monsere to 5 μm. The powders were mixed for 64 hours. From a mixture of hydraulic press extruded billet samples for strength tests. Blanks were specaly in a vacuum furnace type microwave tungsten heaters at a residual pressure of about 30 to 40 PA and a temperature of 1500oWith over 4 cha is meant for filtering molten metals, in which to improve mechanical strength and heat resistance of the ceramic foam filters while maintaining air permeability and porosity, as well as utilization of costly waste FSC, raw material mixture containing phosphate binder, aluminum hydroxide, smoothly, potassium salt and the refractory filler further comprises a waste PCF in the following ratio, wt.%: phosphate binder - 2,5-30; aluminum hydroxide 1-3; flux - 1-12; potassium salt is 0.5 - 10; wastes from the production of FSC - 10-30; refractory filler - rest [7].

A known method of manufacturing a porous ceramic filter elements of the mass, including the filler from the group of chamotte, corundum, porcelain, glass, and clay and organic bunch, whereby the weight further comprises hydrophilizing graphite in the following ratios, wt.%: clay 0.5 to 45, 0mm; organic bond of 0.1 to 7.0; hydrophilizing graphite (in terms of dry substance) of 0.5 to 50.0; filler rest, and hydrophilizing graphite represented by particles with size less than 5 microns, and the filler particles with the size less than 50 microns. Porous ceramic filter elements obtained from the mass according to the JV the East of cellular materials such as glass carbon, including the application of thermosetting resin foam and the subsequent three-stage heat treatment of the obtained preparations: polymerization at 150oWith carbonation, carried out in the temperature range 150-1000oC and heat treated at 2000-2500o[9].

A method of obtaining highly porous cellular ceramic materials for thermal protection and filtering, including the application of a suspension of ceramic powders SiO2, Al2O3, ZrO2and a binder on a foamed polyurethane polymer and subsequent heat treatment, in which the sintering of the ceramic powder and burnout polyurethane foam [10].

The closest in technical essence and the achieved when using the result (the prototype) is a porous ceramic material and method for producing the porous ceramic of aluminum oxide with a particle size of from 1 to 200 μm and mineral bundles of compounds based on simple or complex oxides of aluminum, silicon, calcium and magnesium, having an open porosity of not lower than about 48. % and mainly over 55 vol.%, a narrow distribution of pore size is the coefficient of variation of the pore size does not exceed 0.2. The method of obtaining porous Carmichael as a source of mineral components ligament using a mixture of simple or complex oxides of silicon, aluminum, calcium and magnesium in hydraulic or easily gidratirovana form, preferably with a particle size of not more than 1 μm, mixing them with the filler is carried out in aqueous medium prior to the formation of a suspension with a concentration of water of 20-40 wt.%, followed by exposure of the obtained aqueous suspension at 50-120oFor 3-20 h for formation of the crystalline structure, then a structured mixture reinforce to obtain the target product or a thermal treatment 120-400oWith, or by hydrothermal treatment at a temperature of 180-220o[11].

The disadvantage of ceramic of alumina is the complexity of technology, the duration of the manufacturing operations, as well as the discrepancy of the obtained material parameters of ceramic materials permitted for use in medical technology.

TASKS AND TECHNICAL RESULT.

The objectives of the present invention and the required technical result achievable with the use of the invention is to simplify the technology for obtaining high-quality ceramic materials and ceramic products based on alumina with providing possible application of new ceramic foam material and products of medical purpose is logicnet ceramic medical devices from the available cheap raw materials while increasing quality indicators ceramic material and enable the manufacture of ceramic products in particular implants and implants with complex anatomical shape of the surface and the required parameters of the ceramic material, while ensuring the possibility of manufacturing a structural ceramics used in the industrial production of medical ceramics, glass, porcelain, metal melts and other products.

THE ESSENCE OF THE INVENTION.

The tasks are solved and the required technical result from the use of the invention is achieved in that according to the invention the ceramic foam material based on alumina, has the structure of a solid ceramic foam and contains not less than 98,0% by weight aluminum oxide, 0.15 to 0.4 wt.% magnesium oxide, not more than 0.1 wt.% silicon oxide and not more than 0.1 wt.% iron oxide, while the ceramic foam material has a bulk density of 0.1-2.4 g/cm3open porosity 40-96%, macropores in the range of 0.1-15 mm, and the micropore size of 0.0001 to 0.1 mm.

This material retains its shape when heated to temperatures of 1700-1800oC and the melting temperature of the material is 2040oWith, the material is white or white-yellowish or white-grayish color with an average grain size of the oxide of 0.5 to 15.0 μm.

When used in medical izdeliya 0.4 to 2.5 mm, micropore size of 0.001-0.1 mm and contains a minimum of 99.5 wt.% aluminum oxide, 0.2 to 0.4 wt.% magnesium oxide, not more than 0.1 wt.% silicon oxide and not more than 0.05 wt.% iron oxide.

The ceramic foam material is obtained on the basis milled in an aqueous medium containing at least 90 wt.% alumina in the alpha phase of alumina by preparing a ceramic slurry, forming organic foam or molded with vigorem filler or molded by foaming ceramic slurry, drying, sintering-carbonization and calcination or on the basis of ground in the aquatic environment contained alumina in the alpha phase of alumina by preparing a ceramic slurry, forming by foaming ceramic suspension lacanfora emulsion, drying, sintering-carbonization in an oxidizing atmosphere, and firing in an oxidizing atmosphere.

One or more surface or the inner layers of material have a monolithic structure without open porosity and water absorption, bulk density of the layer of material with a monolithic structure of 3.80 3.98 g/cm3, bending strength 150-750 MPa, compressive strength of 1000-7500 MPa identical chemical composition.

The tasks are solved and the desired tekhnicheskogo material made of ceramic foam material, obtained on the basis of containing alumina in the alpha phase of alumina containing at least 98 wt.% aluminum oxide, 0,15-0,40 wt.% of magnesium oxide and not more than 0.1 wt.% silicon oxide and not more than 0.1 wt.% iron oxide having a bulk density of 0.1-2.4 g/cm3open porosity 40-96%, macropores in the range of 0.1-15 mm, the micropore size of 0.0001 to 0.05 mm, and the ceramic material is described above.

This ceramic material has at least one surface or inner layer with a monolithic structure without open porosity and water absorption with a volume weight of 3.80 3.98 g/cm3, a Flexural strength of 150-750 MPa, compressive strength 1500-7500 MPa and an average grain size of the oxide of 0.5 to 15.0 μm.

While the ceramic foam material of the product has alternating layers of ceramic foam and a monolithic ceramic material.

In addition, the product is made in the form of medical devices, for example in the form of the endoprosthesis or the implant for contouring, repair, correction, replacement or removal of defects, damage or deformation of facial or cranial, or joints, or other bone or cartilage, while the product has a layer of penetrates or cartilaginous tissue and a layer of a monolithic ceramic material, located from the contact of the endoprosthesis or the implant after implantation of the soft tissues, for example, in the form of the endoprosthesis or the implant is performed with anatomical form or anatomical surface profile that is identical or similar anatomical shape, or anatomical surface profile of the lower jaw or mandibular angle, or articular process with the angle of the mandible, or alveolar process, or the masking of the zygomatic bone, or mental chin bone, or top-side edge of orbit, or the lateral edge of the eye socket or the bottom of the eye socket or bone paranasales area, or bone zygomatic bone, or bone skolealderen ridge, or the bridge of the nose, or nose ear curl, or other bone or cartilage, or their separate parts, while the ceramic material contains a minimum of 99.5 wt.% aluminum oxide, 0.2 to 0.4 wt.% magnesium oxide, not more than 0.1 wt. % silica and not more than 0.05 wt.% iron oxide, and the product has a layer of ceramic foam material located at the side of contact of the endoprosthesis or the implant after implantation with bone, or contact the endoprosthesis or the implant after implantation with bone or cartilage tissue and a layer of monolithic ceramics is their tissues.

While the product in the form of the endoprosthesis or the implant includes means for fixing its position on the bone or cartilage or soft tissue, made for example in the form of holes and/or protrusions and/or depressions or other similar purpose funds are committed.

In addition, the product is made in the form of cylindrical or spherical grinding media for ball mill or in the form of the element facing a ball mill or an element of the protective lining or stand high temperature of the device or in the form of a protective case for thermocouples or other probe or device or in the form or capacity of the channel for fused or corrosive materials or in the form of item high temperature devices.

The tasks are solved and the required technical result from the use of the invention is also achieved by the fact that according to the invention Panoramico made of alumina, containing not less than 98,0% by weight aluminium oxide, including those containing not less than 93 wt.% alumina in the alpha phase, 0,15-0,45 wt.% magnesium oxide, not more than 0.1 wt.% silicon oxide and not more than 0.1 wt.% iron oxide by grinding of alumina in water to an average particle size of 0.5-3.5 μm, pany with vigorem filler or molding foaming ceramic suspension lacanfora emulsion or molding in plaster moulds, sintering-carbonization in an oxidizing atmosphere at a temperature of 1150-1250oWith and firing in an oxidizing atmosphere at a temperature of 1750-1790oC.

This is made of ceramic material or the products described above composition and quality.

THE LIST OF DRAWINGS.

Disclosure of the invention illustrated by the drawing, which shows products from medical ceramics according to the invention.

In Fig.1 shows a section of a layer of the combined ceramic material according to the invention, consisting of a surface of a monolithic layer of ceramic material 1 and a porous or foam-ceramic layer of the ceramic material 2.

In Fig.2 depicts a photo with three variants of the structural design of filters for cleaning of metal, made of porous ceramic foam material according to the invention.

In Fig. 3 shows a photograph of the fabricated according to the invention of item based heat insulation ceramic foam material according to the invention with an operating temperature of 2000oWith, volumetric weight 0.1-1 g * cm3open porosity 65-85%, the size of the macropores of 0.4-2.5 mm and the size of the pores in the walls of the macropores 0,001-0,1 mm

In Fig. 4 shows a photograph of the different variants of filters for deep the ical material according to the invention.

INDUSTRIAL FEASIBILITY.

Disclosure of the invention is illustrated on the example of the disclosure manufacture, as well as experimental and clinical studies of the effectiveness of the use of medical ceramics according to the invention, showing the industrial feasibility of the invention and the possibility of realization of the invention industrially.

Ceramic implants made of alumina brand PMK on TU-48-5-200-79 production of JSC "Boksitogorsk Alumina Leningrad region by preparing slurry (ceramic slurry), molding, drying, pre-sintering-carbonization and calcination in an oxidizing atmosphere.

Thus it is established experimentally that the ceramic material is required according to the invention and quality medical products from it can be obtained on the basis of containing not less than 93 wt.% alumina in the alpha phase of alumina in the presence of material not less than 98,0% by weight aluminium oxide, preferably 99,5-of 99.85 wt.% aluminum oxide, 0.15 to 0.4 wt.% magnesium oxide, not more than 0.1 wt.% silicon oxide and not more than 0.1 wt.% iron oxide, preferably not more than 0.05 wt.% iron oxide, not more than 0.1 wt.% the sum of the oxides of sodium and potassium in terms of oxide n the infernal region or similar in composition alumina according to GOST 30559-98.

It is found experimentally that for ceramic material of the required quality containing alumina in the alpha phase alumina appropriate composition to activate the surface of its particles, the optimum shaping, reducing shrinkage during firing and sintering, as well as to improve the quality, you must first grind in the aquatic environment to an average particle size of 0.5-3.5 μm, to produce implants in plaster moulds with getting compacted due to partial dehydration of gypsum form the surface layer of the slurry, drying, annealing and sintering in the above process parameters.

Thus it is established experimentally that the preliminary sintering in an oxidizing atmosphere at a temperature of 1150-1250oWith allows to produce billets implants, implants and structural ceramics that can be processed using mechanical methods to give them the desired shape and size, preliminary quality control of material structure and integrity of its surface, and the final calcination in an oxidizing atmosphere at a temperature of 1750-1790oWith lets get ready implants required quality and size.

Entativ and structural ceramics according to the invention it is expedient to use alumina brand PMK on TU-48-5-200-79 production of JSC "Boksitogorsk Alumina Leningrad oblast or alumina of similar quality or GOST 30559-98.

It was established experimentally that, in order to obtain a monolithic ceramic material without open porosity and water absorption of the required quality and strength characteristics alumina appropriate composition of soybean holding not less than 93 wt.% alumina in the alpha phase to activate the surface of its particles, the optimum shaping and sintering must be pre-grind in the air or in the water environment with getting ultradistance polyrational ceramic suspension (slurry) density of 2.2-2.8 g/cm3to produce billets implants in plaster moulds, drying, annealing in an oxidizing atmosphere at a temperature of 1150-1250oWith and sintering in an oxidizing atmosphere at a temperature of 1750-1790oC.

With experimental medical devices in the form of endoprotheses (implants) were all required for medical devices and materials of sanitary-chemical testing, Toxicological-hygienic and clinical trials.

Thus it is established experimentally that the ceramic material of the endoprosthesis of the required quality can be obtained on the basis of containing alumina in the alpha phase of alumina in the presence of the material of 99.5-of 99.85 wt.% aluminium oxide is inazuma brand PMK on TU-48-5-200-79 production of JSC "Boksitogorsk Alumina Leningrad oblast or other similar composition of alumina.

It is found experimentally that for ceramic material of the required quality containing alumina in the alpha phase alumina appropriate composition to activate the surface of its particles, the optimum shaping, reducing shrinkage during firing and sintering, as well as to improve the quality, you must first grind in the aquatic environment, to mould, drying, annealing and sintering in the above process parameters.

The results of extensive testing of the new ceramic material implants of him in the all-Russian scientific-research and testing Institute of medical technology of the Ministry of health of the Russian Federation showed that the used ceramic material and implants (implants) from Toxicological-hygienic and sanitary-chemical indicators meet all the requirements of the medical devices of similar purpose.

Studies have been conducted of bioinertness and biocompatibility of implatation with dense, porous and composite structure of this ceramic material in RIICO them. P. P. Yet. The object of the study was ceramic implant the manufacture of implants made of ceramic material according to the invention was used alumina brand PMK on TU-48-5-200-79 production of JSC "Boksitogorsk Alumina Leningrad region.

In experiments were used 72 animals, divided into two series. The number of animals at time of observation - 4. The timing of breeding animals from the experiment: 1, 2, 3, 4 weeks and 2, 3, 4, 5, 6 months. Electron microscopic examination was used for a detailed study of the contact of the ceramic incantatem with the bone tissue. The study was performed on a scanning electron microscope ISM-840 A (Jeol, Japan). For elemental analysis and generation of distribution maps elements used energy dispersive analyzer'AN 10/85S (Link Analitical, England). When conducting the research were used the most informative and modern research methods with the volume of material sufficient to justify the following conclusions: - In the experiment on animals proved bioinert and biocompatibility with respect to bone implants made of ceramic material, the claimed composition and the technology of production.

In the course of research on any term monitoring of laboratory animals was not observed the formation of a connective tissue capsule around the implant, revealed the absence of all periods of observation, both local and General inflammatory response to the implanted ceramic obrazcy and installed, when intramedullary implantation of ceramic monolithic rod in the femur of rats around it was observed the formation of bone capsules for 3 months. At follow-up bone tissue consistently transformed into neobrazovannoe spongy bone, and then the plate tightly in contact with the implant. However at no time was found to education components of the connective tissue (fibroblasts, collagen fibers and cellular structures) between bone and ceramics.

- When an intramedullary implant stem from a combination of ceramics in the femur of the rat-side thick part (as in the first series) was observed the formation of bone capsules to 3 months; bone tissue consistently transformed into the newly formed spongy bone and then into the plate and her tight contact with the implant. Side porous portion from the second week was observed ingrowth of newly formed bone beams deep into the pores of the implant with subsequent restructuring in Mature bone tissue. In the same way as in the first series of experiment, on any observation period was not observed the formation of elements of connective tissue (fibroblasts, collagen is scientist positive results allowed to conclude about the feasibility of conducting a clinical trial implants of similar ceramics, ceramic implants made of the material of this composition is suitable for use in traumatology, orthopedics, reconstructive Oncology, maxillofacial surgery and can be used in clinical practice on the basis of compatibility with bone and soft tissues, bioinertness and biocompatibility, nontoxicity, and ease of sterilization in air at 180oC.

Clinical trials of this ceramic material and ceramic implants according to the invention were carried out in the prescribed manner at the St. Petersburg state medical University named after academician I. P. Pavlov. Ceramic implants have been used for defects and deformation of the bones of the facial skull and brain in 12 patients (3 women and 9 men) aged from 20 to 62 years. In 3 patients the defects of the mandible, the zygomatic bone was the result of surgical intervention regarding tumors, the remaining patients deformation of the facial bones, the frontal bone has arisen as a result of trauma, childhood osteomyelitis of the mandible, or was a congenital malformation.

Examination of patients before surgery included: x-ray facial bones and Cerebro is research - clinical analysis of urine and blood tests, blood tests, ECG, chest x-ray, consultation of experts in the presence of concomitant pathology.

All surgical interventions were performed under General anesthesia. In 12 patients was performed 14 surgical intervention. In 5 cases a surgical procedure, the introduction of ceramic implant was carried out from the oral cavity, i.e. in terms of an infected receiving bed. In the postoperative period, all patients underwent prophylactic antibiotic therapy.

All operated patients were able to compensate for the defect and fully or partially eliminate the deformation, i.e. to get a good or satisfactory aesthetic effect from the treatment. Any reactions to the ceramic implant in the early postoperative period and in the long term after surgery (up to 1.5 years) was not observed.

As a result of clinical trials, it was found that the ceramic material and articles thereof meet all the requirements for medical and technical requirements. They are recommended for production and use in medical practice and in nastawienie testing new ceramic implants in the Military medical Academy, clinic of maxillofacial surgery and dentistry in the prescribed manner to explore new used in dentistry materials when performing operations with the aim of defects, remove the deformations of osseous structures, resulting from injury and inflammation, showed that the samples of ceramic implants and elements of the jaw bones and jaw all medical tests have passed and can be recommended for the organization of their production and application in medical practice. It was held on 31 operative intervention in patients with injuries of the facial skeleton, including deformities and defects of all areas of the face and complications in neither case was not identified. It is established that the prosthesis is stable, effective upon the replacement of defects and correcting deformities of the facial skeleton with good cosmetic and functional result can be shown for reconstructive maxillofacial surgery.

Clinical trials of prototypes implants in the clinic of maxillofacial surgery and dentistry, Moscow regional research Institute. M EOF.Vladimir (MONICA) for 32 patients aged from 17 to 53 years with injuries of the facial skeleton, including deformities and defects of the middle and lower areas of the face showed that implants resistant to stress, recently applications in reconstructive maxillofacial surgery and can be recommended for mass production and application in medical practice.

The results of extensive testing of the ceramic material of the implant in the all-Russian scientific-research and testing Institute of medical technology of the Ministry of health of the Russian Federation showed that the used ceramic material and implants from the Toxicological-hygienic and sanitary-chemical indicators meet all the requirements of the medical devices of similar purpose.

As a result of clinical trials, it was found that the ceramic material and articles thereof meet all the requirements for medical and technical requirements. They are recommended for production and use in clinical practice and is currently preparing their industrial production for wide use in medical practice.

Clinical studies have confirmed the use of implants and implant of a new ceramic material for a number of diseases, in particular if microgenia, secondary deformities of the lower jaw after childhood osteomyelitis and burn, the deformation of the frontal region with the retraction in the compression re the cosmetic result.

In addition were made and samples obtained ceramic foam material petrographic method. The results of petrographic studies on some of the samples are shown in the following examples.

Example 1. Sample 1. Section 7. Large pores are spherical in shape, are connected with each other. Size you can select the 2nd class day. Large pores (macropores) have a size of 1-4 mm, small pores (micropores) in the range of 0.1-0.3 mm, located in the walls of the macropores. The total porosity is 95%. Grains of corundum are mostly wrong isometric shape and size of 10-40 microns, an average of 13 μm. Intergranular pores wrong isometric form, the size of 5-30 microns.

Example 2. Sample 2. Section 8. Large pores are spherical, rather oval in shape, are connected with each other, the pore size of 0.5 to 1.2 mm, there are only a few small spherical pores in the walls of the macropores, the Total porosity is 95%. Grains of corundum are mostly wrong isometric shape and size of 10-30 μm, about 12 μm. Intergranular pores wrong isometric shape, size 1-25 microns.

Example 3. Sample 3. Section 9. Large pores are greatly elongated or rectangular shape, the pores are communicated between somaticheskoe and tabular form, the size of 5-25 μm, about 12 μm. There are 3 types of intergranular pores: 1) incorrect isometric shape, size 5-35 microns, 2) spherical shape, the size of 20-50 microns, 3) channel, partially interconnecting pores of a width of 10-20 μm and a length of more than 60 μm.

Example 4. Sample 4. Cut 10. Large pores are elongated or rectangular irregular shape, the pores are connected with each other. Width of the pores is from 0.2 to 1.0 mm, the Total porosity is 60%. Grains of corundum are isometric polygonal and tabular form, the size of 5-30 microns, an average of 14 μm. Intergranular pores: 1) incorrect isometric form, the size of 2-30 μm, an average of 8 μm and 2) the channel pore width of 20-30 microns.

Example 5. Sample 5. Cut 11. Large pores are spherical in shape, are communicated between a size of 0.4 to 1.2 mm, the Total porosity is 80-90%. In the walls of the macropores are sporadic spherical pore size on the order of magnitude smaller. Grains of corundum are mostly polygonal isometric and size of 5-30 μm. Intergranular pores wrong isometric shape, size 2-35 μm.

Besides ceramics material according to the invention were made and tested in production environment the production of glass and porcelain in the form of various what samostojnost when heating a portable gas burner up to t=1000oWith 1 minute, wear resistance and resistance to 1700oC - crucibles for the synthesis of pilot lots of Windows, providing the melting of low-melting and high-melting glass to a temperature of 1700oWith, withstand, without fracture, 20-30 bottoms in the air - porous ceramic trays for transporting molten glass drops, which proved highly resistant products to alternating thermal loads, chemical resistance against molten glass, high wear resistance at room temperature, and under conditions of exposure to high temperatures, high temperature stands for charge porcelain that can withstand up to t=1700oWith both on the air and in a reducing atmosphere, is a highly effective insulation on the basis of the ceramic foam material with an operating temperature up to 2000oWith bulk density of 0.1 to 1 g/cm3open porosity 65-85% and the size of the macropores of 0.4-2.5 mm and a pore size in the lintels of 0.001-0.1 mm in blocks that are installed in the space between the heaters and sintered products. Due to the cellular structure of the blocks is heated from the heater, creating a uniform temperature field in the furnace as height and width, and the entire volume is ravnomernogo heating products decreases marriage porcelain deformations and leashes. Of particular interest they represent the firing dimensional shaped articles of porcelain (floor vases, decorative panels and other). In this case, porous blocks on the basis of aluminum oxide play a role of heat shields, and every product from all sides obkladyvaetsja these blocks. The resource of their work with careful handling shows a possible implementation of the invention industrially, as well as possible solutions to the tasks and confident of achieving the desired technical result.

All that proves the possibility of realization of the invention industrially, the possibility of solving problems and achieving the required technical result.

THE CRITERIA FOR ELIGIBILITY.

The above detailed description of the features of the new ceramic foam material based on alumina and design features manufactured ceramic products't leave any doubt as to their feasibility - all elements of the technical methods of manufacture and use of ceramic materials and ceramic materials known in the art of ceramics and medical technology, well-developed modern techniques of ceramic materials and MEA by well-known experts and widely used in practice, the manufacture of ceramic products separate techniques, described, for example, in the book of Balcewicz C. L. Technical ceramics. M.: Stroiizdat, 1984.

In the manufacture of porous ceramic foam material can be applied known in the art and widely used in the practice of separate technological methods of manufacturing porous and foamed materials are described, for example, in the book of O. G. Tarakanov, I. C. Shamov and C. D. Alpern. Filled foams. M.: Chemistry, 1989, 216 S.-depth look at techniques for the production of filled composites containing particulate fillers.

Detailed analysis of the existing prior art shows a lack of open and accessible sources of information unique set of features which would be identical with the whole set of essential features of the invention. Therefore, the claimed technical solution meets the criteria of "novelty."

The tasks are solved in the original, simple, but not previously known method, the invention enables to solve tasks and to provide a new previously unknown positive result.

Ceramic materials and products according to the invention can be manufactured from readily available and cheap andáspecial equipment. When using inventions in medicine and in other fields they produce the required technical result. Therefore, the proposed technical solution meets the criterion of "industrial applicability".

In General, given the novelty and non-obviousness of the invention, the materiality of all the General and specific features of the invention (shown in the section "summary of the invention"), and also shows the industrial feasibility of the invention, a solid solution of the tasks and achieving the desired technical result of the claimed technical solution of the urgent tasks meets all requirements for eligibility requirements for inventions.

In addition, analysis of the essential features of the invention group and the unity achieved when using the technical result shows the existence of a single General inventive concept, the close and indissoluble connection between the invention of the group. This allows you to combine the three inventions in one application.

SOURCES OF INFORMATION 1. International standard ISO 6474-81, 1981, 5 C.

2. International standard ISO 6474 1994-02-01, 1994, 6 S.

3. RF application 92006759, 04 35/46, 35/10, publ. 1995.04.20.

4. RF patent 2119901, With>7. RF application 93008852, 04 38/00, publ. 1995.05.20.

8. RF application 94040010, 04 38/00, publ. 1996.11.10.

9. U.S. patent 3574548, 01 31/02, publ. 1971.

10. Patent UK 2168337, 04 35/00, publ. 1986.

11. RF application 95101198, 04 38/00, publ. 1996.12.10 (prototype).

Claims

1. The ceramic foam material, wherein the material based on alumina, the material has the structure of a solid ceramic foam and contains not less than 98,0% by weight aluminum oxide, 0.15 to 0.4 wt.% magnesium oxide, not more than 0.1 wt.% silicon oxide and not more than 0.1 wt.% iron oxide, the material has a bulk density of 0.1-2.4 g/cm3open porosity 40-96%, macropores in the range of 0.1-15 mm, and the micropore size of 0.0001-0.1 mm, melting point material is 2040With, the material is white or white-yellowish, or white-grayish color, the average grain size of the oxide material is 0.5 to 15.0 μm.

2. The ceramic foam material under item 1, characterized in that the material has a bulk density of 0.1-1.5 g/cm3open porosity 65-85%, macropores with a size of 0.4-2.5 mm micropore size 0,001-0,1 mm

3. The ceramic foam material according to any one of paragraphs.1 and 2, characterized in that the material contains a minimum of 99.5 wt.% oxide lumicisi material according to any one of paragraphs.1-3, characterized in that the material obtained on the basis milled in an aqueous medium containing at least 90 wt.% alumina in the alpha phase of alumina by preparing a ceramic slurry, forming organic foam, or molding with vigorem filler, or molded by foaming ceramic slurry, drying, sintering-carbonization and calcination.

5. The ceramic foam material on p. 4, characterized in that the material obtained on the basis milled in an aqueous medium containing alumina in the alpha phase of alumina by preparing a ceramic slurry, forming by foaming ceramic suspension lacanfora emulsion, drying, sintering-carbonization and calcination.

6. The ceramic foam material according to any one of paragraphs.1-5, characterized in that one or more surface or the inner layers of material have a monolithic structure without open porosity and water absorption with a volume weight of 3.80 3.98 g/cm3and a Flexural strength of 150-750 MPa.

7. The product of a ceramic material, characterized in that the product is made of ceramic foam material based on alumina, containing not less than 98,0% by weight aluminum oxide, 0.15 to 0.4 wt.% magnesium oxide, not belorizonte 40-96 %.

8. The product under item 7, characterized in that the product is made of ceramic foam material according to any one of paragraphs.1-6.

9. Product according to any one of paragraphs.7 and 8, characterized in that the product has at least one surface or inner layer with a monolithic structure without open porosity and water absorption, bulk density of 3.80 3.98 g/cm3, a Flexural strength of 150-750 MPa, compressive strength 1500-7500 MPa and an average grain size of the oxide of 0.5 to 15.0 μm and a chemical composition identical to the ceramic foam material.

10. The product under item 9, characterized in that the product has alternating layers of ceramic foam material and a monolithic ceramic material.

11. Product according to any one of paragraphs.9 and 10, characterized in that the product is made in the form of medical devices in the form of the endoprosthesis or the implant for contouring, repair, correction, replacement or removal of defects, damage or deformation of maxillo-facial or cranial or articular bone or cartilage, while the ceramic material contains a minimum of 99.5 wt.% aluminum oxide, 0.2 to 0.4 wt.% magnesium oxide, not more than 0.1 wt.% silicon oxide and not more than 0.05 wt.% iron oxide, and the product has a layer of the ceramic foam mevoi cloth and a layer of a monolithic ceramic material, located from the contact of the endoprosthesis or the implant after implantation of the soft tissues.

12. The product is made of ceramic material on p. 11, characterized in that the product is in the form of the endoprosthesis or the implant is performed with anatomical form or anatomical surface profile that is identical or similar to the anatomical shape or anatomical surface profile of the lower jaw or mandibular angle, or articular process with the angle of the mandible, or alveolar process, or the masking of the zygomatic bone, or mental chin bone, or top-side edge of orbit, or the lateral edge of the eye socket or the bottom of the eye socket or bone paranasales area, or bone zygomatic bone, or bone skolealderen crest, or the bridge of the nose, or nose, ear curl or portions thereof.

13. The product of the ceramic foam material on PP.11 and 12, characterized in that the product is in the form of the endoprosthesis or the implant includes means for fixing its position on the bone or cartilage or soft tissue, in the form of holes and/or protrusions and/or depressions.

14. The product of a ceramic material according to any one of paragraphs.7-9, characterized in that the product is made in the form of the element of the protective cover for the measuring sensor or device, or in the form of a ceramic filter, or in the form of ceramic tooling porcelain or glass production, or capacity, or channel, or structural element of the device for processing molten, heated or chemically aggressive materials.

15. A method of manufacturing a foam ceramics, characterized in that Panoramico made by grinding of alumina in water to an average particle size of 0.5-3.5 μm, preparation of ceramic slurry, forming organic foam, or molding with vigorem filler, or molding foaming ceramic suspension lacanfora emulsion, or molding in plaster moulds, sintering-carbonization in an oxidizing atmosphere at a temperature of 1150-1250With and firing in an oxidizing atmosphere at a temperature of 1750-1790With Panoramico made from containing alumina in the alpha-phase alumina, including not less than 98,0% by weight aluminum oxide, 0.15 to 0.4 wt.% magnesium oxide, not more than 0.1 wt.% silicon oxide and not more than 0.1 wt.% iron oxide.

16. The method according to p. 15, characterized in that it is made of ceramic foam material according to any one of paragraphs.1-6.

17. The method according to any of paragraphs.15 and 16, otlichuy the

 

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