RU2737578C2 - Device for bone fracture fixation and method of its manufacturing - Google Patents

Abstract

FIELD: medicine; maxillofacial surgery; surgical dentistry.

SUBSTANCE: group of inventions discloses a bone fracture fixation device and a method for preparing it. Device is characterized by that it comprises plate with through holes installed on bone tissue in area of fracture. Surface of the plate and fastening screws are completely coated with a bioinert, bio-resistant dielectric coating of silicon carbide with thickness of 2 nm to 2 mm. Coating is deposited in vacuum from beam of accelerated charged and/or neutral particles with energy of 30 eV to 15 keV, containing atoms of carbon and silicon. Invention provides barrier function: protection of person from toxic emissions from metal alloys and polymers, protection against biodegradation, biofouling of surfaces of materials of plates and fasteners, protection from galvanism due to dielectric properties of coating, as well as reduced friction coefficient of friction and absence of exfoliation of the coating when screws are screwed into bone tissue.

EFFECT: group of inventions is intended to increase efficiency of treating bone fractures with the help of bone plates.

2 cl, 14 dwg, 3 ex

Description

The invention relates to medicine, in particular, maxillofacial surgery, surgical dentistry, and in particular to devices that allow the successful surgical treatment of bone fractures.

Currently, osteosynthesis is most often used in the surgical treatment of bone fractures using extra-bone fixators made in the form of plates made of titanium alloys containing titanium and alloying additives, and / or stainless steel (iron alloy with alloying additives), with holes, through which the screws (miniplates) are made of stainless steel from Champy (UK) contain 17.2% Cr and 14% Ni [1].

Pure titanium is practically not used for the manufacture of bone plates and other medical devices used for osteosynthesis, due to insufficient physical, mechanical and strength properties.

Titanium alloys 6AL4V and 6AL4V ELI are titanium alloyed with 6% aluminum and 4% vanadium. This alloy is common for medical procedures. [2] From it, in particular, are made medical products containing such structural elements of devices for fixing a bone fracture, such as plates, wires, pins. Alloys Ti-6AL-4V and Ti-6AL-4V ELI can withstand heavy loads, so they are also used in dental prosthetics [2].

Plates used in surgical practice and fasteners for them are made of alloys that reduce the likelihood of metalosis [3, 4, 5].

When human tissues come into contact with the structural elements of devices for fixing a bone fracture, made of alloys containing alloying additives, the content of Fe, Ni, Ti, Cr increases in the body. The combination of different grades of steel and / or titanium in the plate and fasteners increases the likelihood of galvanic effects and metallosis. A number of metals are known that adversely affect the rate of healing of injuries. For this reason, combinations of chromium with cobalt, titanium with vanadium, nickel in a high percentage with any metals are excluded in alloys. Metal parts are particularly susceptible to corrosion, in particular, implants containing iron, sodium, potassium, cobalt, which pass into electrolytes [3, 4, 5].

Galvanic currents arise in the patient's oral cavity when there are structural elements in it, for example, fillings, prostheses, plates, screws containing various metals. Since saliva is an electrolyte with an acidic environment, a constant electric current of various magnitudes arises between the metal structures [5].

The degree of corrosion of plates, fasteners and implants directly affects the pH environment, which can lead to pyoinflammatory complications [3].

Known technical solution, according to which to prevent galvanism, a dielectric coating of tantalum pentoxide is applied to the surface of metal structural elements [5].

The disadvantage of this technical solution is that the composition of the coating includes a metal that is toxic.

A technical solution is known according to which the following structural elements of devices for fixing the fracture are used in the treatment of a fracture of the bones of the maxillofacial region: stainless steel wire of grades 1X18H9T, EP-400, EYAT-1, titanium, tantalum, nylon thread with a diameter of 0.6-0 , 8 mm, fast-hardening plastics, osteoplast glue [6]. In addition, nickel-titanium wire staples are used [6].

The disadvantages of the technical solution, which consists in the use of metal alloys and polymers, is that polymer materials undergo biodegradation, release toxic compounds, and metals are toxic.

Water-soluble compounds have the greatest ability to penetrate into the cell [7]. For example, a water-soluble metal ion such as the chromate ion (CrO ₄ ) ^2- can easily penetrate cells using the (SO ₄ ) ^2- - transport system. Fat-soluble metal compounds, such as nickel carbonyl Ni (CO) ₄ , easily enter the cell and are therefore very toxic [7].

With prolonged contact with the biologically active media of a living organism, medical devices are partially destroyed, and some of the chemical substances that make up their composition migrate into the surrounding human tissues. These substances are mainly metals [7].

The excess content of metal ions in the body produces a toxic effect. Toxicity is explained by the binding of "metal poisons" in the body with functional groups of vital substances, which disrupts the normal functioning of tissue cells [7, 8, 9].

The disadvantage of the known technical solution to use medical products, in particular, elements of devices for fixing a bone fracture, made of metal alloys, is that the metals and alloying elements that make up their composition are toxic to humans.

The technical solution to the issue of blocking the release of ions of toxic elements from metal alloys and toxic components from polymeric materials and alloys used for the manufacture of medical devices, in particular, structural elements of devices for fixing a bone fracture, is the formation on the surface of functional coatings that do not contain metals [5, ten].

Known technical solution, according to which on the surface of medical products, in particular, intraosseous implants from titanium alloys, a titanium oxide layer is formed by the method of microarc oxidation [10].

The disadvantage of the technical solution is that the coating material - titanium dioxide is a genotoxic material [8, 11].

A known method of producing an anodic oxide coating on parts made of titanium alloys [12]. The method includes the operation of obtaining an anodic oxide coating on parts made of titanium alloys by electrochemical treatment at a voltage of at least 200 V in an electrolyte containing phosphoric acid 20-35 g / l, sulfuric acid 365-385 g / l, molybdenum acid sodium 2 , 5-12.0 g / l sodium tungsten acid 3.5-16.5 g / l and rhenic acid 2.5-12.5 g / l. EFFECT: obtaining an anodic-oxide coating consisting of TiO ₂ with anatase structure [12].

The disadvantage of the technical solution is that titanium dioxide is genotoxic [8, 11].

Known technical solution, according to which on the surface of medical products, for example, metal fixed dentures, in a vacuum by arc deposition, a titanium nitride coating is formed [13, 14].

In addition to the traditional method of applying coatings using vacuum-arc installations of the Bulat type, modified versions of the processes have been developed, in particular, methods of plasma-ion implantation and deposition with the supply of a constant or pulsed voltage to the workpiece [15]. The process of applying films in vacuum consists in creating (generating) a stream of particles directed towards the treated surface and subsequent condensation of these particles on the surface to be coated with the formation of thin-film layers. Thus, when applying thin films, three processes occur simultaneously:

1) generation of a directed stream of particles of the deposited substance;

2) the flight of particles in the volume of the technological chamber from the source to the treated surface;

3) contact of particles with the treated surface and the formation of a thin-film coating [15].

Disadvantages of the technical solution: traditional methods and equipment for arc coating require a relatively high application temperature, usually from 300 to 850 ° C. In modernized installations, the temperature of the samples is from 100 to 500 ° C. This causes deformation of products, especially of thin structural elements. In addition, the components of the prosthesis material and titanium from the coating enter the human tissue, which does not always have a beneficial effect on the patient, especially in diseases of the gastrointestinal tract [16].

Known technical solution, according to which the bone plate and fixing spikes are made of a metal alloy grade X25K15YUB or martensitic steel grade EX9K15M with a nickel coating with a thickness of at least 12 microns [17].

The disadvantage of the technical solution: the composition of the materials of the plate and spikes, as well as the coating, include metals that cause undesirable effects in the human body. Nickel is toxic and carcinogenic. Allergic lesions are known among bank tellers who dealt with coins made from alloys containing nickel.

Known technical solution, according to which medical products in contact with human tissues are made of polymer materials, in particular, dentures, bone plates, fixing screws [18, 19].

The disadvantage of the technical solution is that polymer materials in the human body are actively adsorbed by microorganisms, biofouling and biodegradation. In addition, they release toxic components, in particular, unpolymerized monomers, thickeners, polymerizers, dyes, and hardeners [19].

The purpose of the invention is to increase the efficiency of operations for the treatment of bone fractures and reduce the treatment time due to the use of a new coating material, namely silicon carbide formed in vacuum from beams of accelerated particles on the surface of structural elements of devices and a method of manufacturing devices for fixing a bone fracture.

The claimed device contains on the surface of structural elements a new material, namely silicon carbide, obtained by ion-plasma deposition in vacuum from a beam of accelerated particles.

According to clause 10.7.4.3. (2) "... The signs used to characterize devices [20]:

To characterize devices, the following features are used, in particular:

- the material from which the element (s) or the device as a whole is made ... ".

The closest to the claimed device is a technical solution, according to which a device including a bone plate with through holes and fixing screws, characterized in that the plate and screws are made of a polymer material based on lactide [18].

FIG. 1 shows a plate (1) with through holes (2) and fastening screws (3), which are inserted into the through holes of the plate and fasten the plate to the bone fragments.

The disadvantage of the technical solution is that polymers undergo adsorption of microorganisms, biofouling, biodegradation and release toxic substances, in particular, dyes, thickeners, hardeners, polymerizers, unpolymerized monomer molecules [19].

The use of new material and new essential features indicates that the claimed device meets the criteria of "novelty" and "significant differences".

The essence of the proposed invention as a technical solution.

The claimed technical solution is a device for fixing a bone fracture, consisting of a plate with through holes and fasteners, such as screws, and on the entire surface of the plate, including the outer surface of the plate and the inner walls of the holes, as well as the outer surface of the fasteners, for example, screws , an ion-plasma coating of silicon carbide was applied, formed in vacuum by deposition from beams of accelerated particles with energies from 30 electronVolts (eV) to 4 KeV, containing silicon and carbon atoms, in particular, charged ions and / or neutral atoms and / or radicals , and the thickness of the coating is in the range from 0.1 micrometer (0.1 × 10 ^-6 meters) to 0.8 micrometer (0.8 × 10 ^-6 meters). A schematic representation of the claimed device is shown in FIG. 2. Plate of the claimed device (4), fixing screws (5). The screws pass through through holes (6), the walls of which are coated with silicon carbide (7). The outer surfaces of the plate (4) and screws (5) are also coated with silicon carbide (7). The fastening screws (5) coated with silicon carbide (7) are fastened, for example, screwed, into the bone tissue (8) in the area of the bone fracture (9) through the through holes of the plate (6) and reliably fix the position of the bone fragments relative to each other and the extra-bone plates.

The use of this coating, which does not contain metals, dielectric, bioinert, bioresistant, hypoallergenic, ensures the achievement of a technical result.

A dielectric coating with a sufficiently high surface and volumetric resistance can prevent galvanism when two metals with different electrical conductivity come into contact and when a metal comes into contact with an electrically conductive liquid.

In solid dielectrics, there are two paths for the flow of electric current: through the dielectric and along its surface.

Therefore, to assess the ability of a dielectric to conduct electric current in these directions, the concepts of volume and surface resistance are used.

By volumetric is meant the resistance that a dielectric has when a direct current flows through its volume.

Surface resistance is the resistance that a dielectric has when a direct current flows over its surface.

Volume and surface resistances are determined experimentally.

According to GOST 50499-93 (IEC 93-80), surface resistance can be determined by measuring the resistance between two sections of the sample surface, in this case, the surface of a film applied to the sample surface [21]. The scheme for measuring the surface resistance of a silicon carbide film (7) is shown in Fig. 3. As a measuring device - Ohmmeter (10) was used multifunctional Voltmeter V7-40 with a range of DC resistance measurements from 10 milliohm (10 × 10 ^-3 Ohm) to 20 MegaOhm (20 × 10 ⁶ Ohm) and power supply from 220 B (item 10 in Fig. 3.). As a sample, in particular, a stainless steel plate (11) with a silicon carbide coating (7) on one side was used (FIG. 3). The probes of the measuring device (10) were located on the surface of the film (7). The readings of the measuring instruments in the range of values from Ohms to hundreds of Kiloohms were checked using the R35 Precision Resistance Store. The appearance of a set of these two devices is shown in Fig. 4. Additionally, a MASTECH MS8222H multimeter was used to measure the surface and volume resistance of the silicon carbide film to direct current (Fig. 5). The readings of the devices were checked in the range from MegaOhm units to GigaOhm units using high-resistance resistances of the KEV-5 and KVM brands (Fig. 5).

The circuit for measuring bulk resistance is shown in Fig. 6. In this case, one probe of the measuring device (10) was in contact with the surface of the film (7), and the other - with the surface of the reverse side of the plate (11).

The surface resistance to direct current of a stainless steel plate with a thickness of 0.8 mm without coating according to the readings of B7-40 was R _surf = 0.11 Ohm, volumetric R _about = 0.20 Ohm.

Surface resistance of the film constant current of silicon carbide deposited on the surface of the stainless steel plate, and by indications V7-40 multimeter MASTECH MS8222H was _dressings R> 1 mega volume _of R> 1 megohm. In measurements of surface and bulk resistance of the silicon carbide coating deposited on an insulating mylar film, both devices show DC resistance R _dressing 20> and R mega _about> 20 MEGA. These are the maximum resistance readings for these instruments.

Measurements were made of the volume resistance to direct current of a structure of two plates made of stainless steel (11) with a silicon carbide coating (7) on one of the sides connected by the coatings to each other. The measurement scheme is shown in Fig. 7. The value of the volume resistance to direct current according to the readings of B7-40 and MASTECH MS8222H was R _about > 1 MegaOhm.

An E6-3 teraohmmeter was used to measure the surface DC resistance of a silicon carbide film deposited on the surface of dielectric materials, in particular, sitall (ceramic) plates and glass. The appearance of the device and the holder with samples is shown in Fig. 8. The resistance value was 5 TeraOhm (5 × 10 ¹² Ohm), that is, it is a dielectric [21].

In addition, the surface resistance of a silicon carbide film formed in vacuum from a beam of accelerated particles on the surface of an electrically conductive aluminum foil was measured by impedance spectroscopy using an eliko Quadra Impedance Spectroscopy instrument. Measurements of the surface resistance to alternating current of the silicon carbide coating were carried out in the frequency range from 1.0 to 349 kHz. The obtained values of R _pov from 600 to 800 KΩ, that is, this is a dielectric coating [21].

The high DC and AC resistance of the silicon carbide film coating proves that the coating is dielectric and prevents galvanization.

The minimum energy of bombarding particles accelerated corresponds to the maximum cross section of ionization of the atoms and molecules of 30-100 eV electron impact and chemical bonding energy gap E _b ≈22 eV [23] between the silicon atoms and carbon molecules silicon carbide. That is accelerated in the discharge region of the ion source to the energy E _b ≈22 eV ion and / or molecule (neutralized ion) silicon carbide upon hitting the surface of the substrate dissociate into atoms to form a silicon carbide film surface.

The maximum value of 4 keV corresponds to the energy of the maximum operating voltage supplied to the anode of 4 kV.

During the implementation of the method of manufacturing the device as a source of accelerated particles was used, in particular, a commercially available ion source II-4.0-0.15 ("Radical"), used in industrial vacuum installations for ion-plasma processing [Ion source II-4 , 0-0.15 ("Radical"). Technical description and instruction manual. OTM3.152.001]. The source is an end-Hall accelerator, that is, an End-Hall type accelerator with a “cold” cathode, crossed electric and magnetic fields. It is used as a source of accelerated positive ions and neutral particles for ion-beam etching with ions of inert gases, in particular, argon [ion-beam etching (IBE)], reactive ion beam etching [RIBE] with reactive gases for example oxygen, and ion beam deposition (IBD). Such sources are used for the deposition of chemical compounds from beams of ions of gaseous compounds of complex composition. In particular, for obtaining films of silicon dioxide from a mixture of monosilane and argon. [24] Silicon-containing carbon coatings were obtained from ion beams of organosilicon compounds: hexamethyldisilazane and vinyltrimethoxysilane. [25] Thin films obtained by deposition from ion beams of these compounds are multicomponent coatings, the basis of which is a Si-C matrix.

Ion sources with a "cold" cathode form accelerated particles in the discharge gap with a wide range of energy values: from zero to maximum values corresponding to the value of the accelerating voltage:

where Ε is the energy of singly charged ions when the accelerating voltage is applied to the anode of the source of the accelerating voltage U _yc , keV;

e is the electron charge;

U _accele - accelerating voltage, KV.

The energy distribution of ions and neutral particles is characterized by the distribution function f (E). The probability that ions and / or neutral particles have energies from 0 to ∞ (infinity) is equal to 1 (unity) [26, 27]:

An example of a graph of the distribution function of ions and / or neutral particles formed by an II-4-0.15 source ("Radical") at an accelerating voltage U _accele = 4 KV is shown in Fig. nine.

The distribution function characterizes the fraction of ions dl of the total number of ions (total ion current) Ι ₀ , the energy of which is in the range dE:

where dI is the fraction of ions from the total number with energy dE;

Ι ₀ - total ion current corresponding to the total number of singly charged ions;

dE - energy range.

The most probable energy, expressed in keV, in this source corresponds to approximately half the value corresponding to the value of the accelerating voltage applied to the anode and expressed in volts. The most probable energy E _{nv of} singly charged ions and neutral particles formed during the neutralization of singly charged ions, if an accelerating voltage U _accele = 4 KV is applied to the anode, corresponds to E _nv = 2 keV. [28] Ideally, the energy of all ions Ε should be in the range of values from E = 0 to the energy corresponding to the accelerating voltage U _accele = 4 KV, that is, E = 4 KeV. Consequently, the integral of the distribution function in the energy range from E = 0 to E = 4 keV should be equal to 1 (unity) [26, 27]:

However, experimental measurements have shown that a small part of ions can have a slightly higher energy due to pulsations of the accelerating voltage in the power supply unit (source), from which the accelerating voltage was applied to the anode of the accelerated particle source.

In the source of the accelerating voltage, in particular, in the serial power supply unit BP-94, which was used in this work, there is voltage ripple, therefore, there are particles with an energy slightly exceeding the value corresponding to the accelerating voltage. (Power supply unit BP-94. Technical description and operating instructions. OTM3.508.016). This fraction of accelerated particles in the graph of FIG. 9 is shown by a shaded area.

Part of the accelerated ions is neutralized by the space charge and turns into accelerated neutral particles, for example, radicals. The proportion of compensated ions in the total number depends on the operating mode of the source, the pressure in the volume of the process chamber, and the distance between the ion-optical system of the source and the sample surface. In the case under consideration, this is usually from 1 to 10%. If necessary, a neutralization cathode can be used, for example, a heated tungsten filament cathode, for full compensation (100% neutralization) of the ion charge on the sample surface. Since ions with the same energies are neutralized, the distribution functions coincide and Fig. 9 also characterizes the energy distribution of accelerated neutral particles:

where dN is the fraction of neutral particles with energy dE;

N ₀ - the total number of particles;

dE - energy range.

An example of a graph of the ion energy distribution function shown in FIG. 9 is a continuous line for a continuous function.

According to Wikipedia: “A continuous function is a function that changes without instantaneous“ jumps ”(called discontinuities), that is, such that small changes in the argument of which lead to small changes in the value of the function. A continuous function graph is a continuous line. The function is continuous on a (mathematical) segment, it is limited in it and reaches the maximum and minimum values on this segment. In addition, it takes on this segment all values lying between its smallest and largest values. "

Consequently, when a voltage of 4.0 KV is applied to the anode of the Radical source, accelerated particles can have any energy value in the range from 0 (zero) to a maximum 4.0 keV.

The main recommended operating mode of the source is II-4.0-0.15 ("Radical") 4.0 kW. The plate with the mode numbers is riveted to the body. The maximum ion energy can slightly exceed the energy corresponding to the voltage at the anode, due to voltage ripples in the anode power supply (Fig. 9).

Ionization of atoms and molecules by electron impact occurs in the discharge zone at equipotential lines with the same electric field potential. The maximum voltage (potential) in the "Radical" is at the anode, then the equipotentials are distributed over the volume of the discharge zone, the minimum values are near the output aperture, which is at zero potential, and sag into the hole of the output aperture. An example of the distribution of equipotentials in the discharge zone of the ion source is shown in Fig. 10 [29].

Ionization of molecules in sources with a cold cathode occurs throughout the entire volume of the discharge chamber. Equipotentials are distributed over the entire volume of the discharge zone, therefore, the beam will always contain ions with a range of energy values from 0 (zero) to the maximum value corresponding to the voltage applied to the anode. For the source II-4.0-0.15 ("Radical"), the recommended voltage is 4.0 KV, that is, the maximum energy will be 4.0 KeV.

The literature contains the results of measurements of ion energy distribution functions by the probe method in the positive column of a low-pressure glow discharge in mercury. The discharge current varied in the range from 0.05 to 0.5 A [30]. The following are examples of graphs of ion and atomic energy distribution functions. The results of measurements in a gas discharge of the distribution of ions and atoms of He, Hg and Ar in terms of energies and velocities (Figs. 11-13) showed, first of all, that the distribution differs from the known equilibrium Maxwell distribution [30]. It is also noted that the group of slow ions, which form the energy distribution function, in the region of its maximum has a characteristic velocity of the order of the atomic velocity [30]. The most probable ion velocity is equal in order of magnitude to the most probable velocity of neutral atoms. With the smallest anisotropy of the distribution function, which corresponds to the minimum of the taken energies of 0.05 eV, the coincidence of all three functions is very good [30].

It should be noted that the plots of all energy distribution functions for ions and atoms start from zero, increase smoothly without jumps, reach a maximum, and decrease smoothly. The continuity of the function indicates that accelerated particles can have any value from zero to the corresponding voltage at the anode. These experimental data confirm the results of experimental measurements of the ion energy distribution functions formed by the sources II-4.0-0.15 ("Radical") and "Radical-M-100" and presented in Fig. 14 [28]. The measurements were carried out using a quadrupole mass spectrometer without its own ion source, capable of analyzing only ions due to its combined sweep electric field and decelerating potential.

The ionization energy of silicon carbide molecules according to reference data, in particular, Wikipedia - Ε _ion = 9.3 ± 0.1 eV.

The bond energy between carbon and silicon atoms in a silicon carbide molecule according to the Chemist's Handbook is Ε _sv = 318.2 kJ ≈22 eV [31]. That is, the ion and / or the silicon carbide molecule accelerated in the discharge zone of the ion source to this energy (E≈22 eV) upon impact on the substrate surface dissociates into atoms with the formation of a silicon carbide film on the surface. According to the graph (Fig. 9) of the energy distribution function of accelerated particles, the beam can contain particles with energies from zero to 20 eV. However, silicon carbide molecules with such an energy will not be able to dissociate when hitting the surface with the formation of a silicon carbide film due to the fact that this energy is not enough to break the chemical bond between silicon and carbon atoms.

In addition, the beam always contains ionized carbon and silicon atoms. They ionize according to reference data, in particular, from the Internet, at energies C-E _ion = 11.25 eV, Si-E _ion = 8.15 eV.

The applicants believe that the energy value of particles containing silicon and carbon, E≈30 ± 5 eV, is the lower threshold energy value required for the dissociation of accelerated ions and / or molecules containing carbon and silicon atoms upon impact on the surface and is sufficient to form on the surface of the silicon carbide film.

The exact value can be influenced by many factors, in particular:

- fluctuations in the accelerating voltage,

- instability of the gas supply system,

- errors of measuring systems,

- fluctuations in discharge parameters,

- distribution of ions in the chamber space,

- pressure in the chamber, which changes the number and nature of collisions of ions with gases at the boundary of the discharge zone.

A wide range of energy values due to the nature of the ion energy distribution function, which always starts from zero for sources with a cold cathode, passes through a maximum corresponding to the most probable energy (often 0.3-0.5 of the maximum) and reaches values corresponding to maximum anode voltage (4.0 keV), guarantees that in the beam formed by the source II-4.0-0.15 ("Radical") ions with energies in the range from 30 eV to 4 keV are always present, that is, in the entire declared range of values.

However, it should be noted that a discharge is not formed in the Radical source at an anode voltage of 30 Volts.

An important parameter is the energy of the ionizing electrons. The description gives the range of values from 30 to 100 eV.

This energy range is used to ionize working substances in mass spectrometers.

The ionic current reaches its maximum at electron energies of about 50 eV. Standard mass spectra obtained by electron impact ionization are usually recorded using electrons with an energy of 70 eV [32].

The use of electrons with an energy of 70 eV, in addition to the high ionization efficiency, is also explained by the greater stability of the mass spectrum, that is, the composition of the ion beam. The electron beam is not monochromatic, and the energy spread is very large and can reach 5 eV. [32].

The disadvantage of the technical solution is that a single ionization by electron impact is used, therefore the ion currents are 10 ^-9 - 10 ^-17 A and such ion sources cannot be used for the industrial manufacture of medical devices. [32].

In general, in each application of ion beams, different requirements are applied to the types of sources and parameters of the beams. The most important operating parameters of sources are: ion beam current, type of ions, energy spread [29].

The most commonly used method of producing ions for processing materials with an ion beam is electron impact ionization. This type of ionization is characterized by the transfer of energy to a gas molecule from accelerated electrons. They are formed, in particular, in a gas discharge. Electrons are accelerated by an electric field, and held by a magnetic field [29].

The number of ionizing collisions that an electron undergoes when passing a unit path in a gas at unit pressure is called the differential ionization coefficient S _e . The value of this coefficient depends on the electron energy U _e and the type of gas [29].

To increase the path of ionization and the lifetime of electrons, the forces created by magnetic fields are often used, as in the source II-4.0-0.15 ("Radical"). In ion sources with cold cathodes, a positive potential is applied to the anode with respect to the electrodes of the output aperture, which are at zero potential. The electrons generated in the discharge zone pass through the plasma layer, where the potential changes both in the radial and longitudinal directions. By applying an axial magnetic field, electrons can be kept from hitting the anode [29]. In such crossed electric and magnetic fields, electrons spiral around the lines of force of the magnetic field and oscillate in the longitudinal direction. As a result of ionizing collisions between electrons, atoms and gas molecules, the plasma is constantly replenished with electrons and ions. Primary electrons lose energy and diffuse across the magnetic field lines to the anode. There they collect, resulting in a current between the anode and the electrodes of the output aperture. Plasma completely fills the discharge chamber [29].

Thus, the use of electrons with energies from 30 to 100 eV together with a confining magnetic and accelerating electric fields ensures the stable operation of the ion source, the formation of a beam of accelerated particles suitable for the industrial production of bone plates and fastening screws coated with silicon carbide, and the achievement of the technical result.

The claimed device significantly differs from the prototype in that a new material is applied to the entire surface of each of the structural elements, namely, silicon carbide obtained by the method of ion-plasma deposition in vacuum by deposition from at least one beam (flow) of accelerated particles with energy from 30 eV to 4 KeV, in particular charged ions and / or neutral atoms and / or radicals.

It is the use of a new material - silicon carbide, deposited in vacuum from a beam of accelerated particles, deposited or formed on the outer surfaces of structural elements of the device from all sides, including the inner walls of the holes, is necessary to achieve a technical result, in particular:

- Preventing toxic components of metal alloys and polymers from entering human tissues;

- prevention of galvanic effects in direct contact and / or contact through electrically conductive human fluids, in particular blood, saliva, structural elements made of electrically conductive materials with different electrical conductivity;

- prevention of biodegradation of materials of structural elements;

- reducing the adhesion of microorganisms to the surfaces of structural elements of the device for fixing a bone fracture;

- prevention of biofouling of product surfaces;

- obtaining good adhesion of the coating to the surfaces of materials of structural elements,

- preventing the coating from peeling off the surfaces of fasteners, such as screws, when screwed into bone tissue,

- a decrease in the coefficient of sliding friction of the surface of fasteners, in particular, screws in the bone tissue, and, consequently, a decrease in pressure forces during screwing.

In the claimed device, screws made of metals, alloys and / or polymer materials can be used as fasteners.

The use of new material and new essential features indicates that the claimed device meets the criteria of "novelty" and "significant differences".

Description of the device in statics:

- a plate with through holes, on the entire surface of which, including the inner walls of the holes, coated with silicon carbide, is installed on the bone fracture area directly on the bone tissue;

- through the holes in the plate, fasteners - screws are passed, and the entire surface of the fasteners is coated with silicon carbide. In this case, the dielectric coating protects against the occurrence of galvanic effects when metal parts with different electrical conductivity come into contact with each other, as well as with electrically conductive body fluids;

- fasteners - screws, screwed into the bone tissue in such a way that they hold (fix) the plate and bone fragments together.

Description of the device in action:

- a plate with through holes, completely covered with silicon carbide, is installed directly on the bone tissue in the area of the bone fracture, holes for fasteners are placed along the edges of the fracture;

- fasteners are passed through the holes in the plate - screws completely covered with silicon carbide;

- fasteners such as screws are screwed into the bone and

- the plate is fixed on the bone in the area of the fracture, connecting (fixing) the bone fragments and the plate together.

Closest to the claimed method of manufacturing a device for fixing a bone fracture is a method of forming a thin-film protective coating on the bases of removable dentures, obturators and components of maxillofacial prostheses. RF patent No. 2540227 [33].

Claim of the Prototype Method.

1. A method of forming a thin-film protective coating on products in the form of bases of removable dentures or obturators, or components of maxillofacial prostheses, characterized in that the coating is formed on the basis of silicon carbide (Si _x C _y ) by ion-plasma spraying, while carrying out:

a) loading of pre-prepared samples of products into the volume of the technological vacuum chamber of the ion-plasma treatment unit;

b) pumping out air from the volume of the technological vacuum chamber to a pressure below atmospheric, and not higher than P≈8-9 * 10 ^-3 Pa;

c) cleaning the surface of product samples by supplying an ion source to the discharge zone to a working pressure from P≈1.0 * 10 ^-2 Pa to Ρ≈1.0 * 10 ^-1 Pa working gas, which is used as an inert gas and / or reactive gas and / or mixture of inert and reactive gases;

d) supplying a voltage ion source to the electrodes of the ion-optical system, while turning on the discharge, ionizing the atoms and molecules of the working gas and forming a beam of accelerated ions of inert gases, and / or ions of chemically active gases, and / or ions of mixtures of inert and chemically active gases ;

e) cleaning the surface of product samples and activating it with a beam of accelerated positive ions;

f) stopping the supply of working gas to clean the surface of the prostheses;

g) feeding into the discharge zone of an ion source of an organosilicon compound and / or a mixture of compounds in the gas phase, which contains at least one organosilicon compound containing carbon (C) and silicon (Si) atoms in the molecule, at an operating pressure of P = 1.0 * 10 ^-2 Pa to P = 1.0 * 10 ^-1 Pa;

h) supply of a voltage ion source to the electrodes of the ion-optical system, while the discharge is switched on, the atoms and molecules of the organosilicon compound in the gaseous phase in the discharge zone are ionized and a beam of accelerated ions is formed, which includes carbon (C) and silicon (Si) atoms ;

i) obtaining a film with a thickness of h _min = 2.5 * 10 ^-10 m or a thickness from h = 10 * 10 ^-10 m to h = 1.0 * 10 ^-6 m.

2. The method according to claim 1, characterized in that the coating is carried out on the bases of removable dentures, obturators and components of maxillofacial prostheses made of acrylic plastics;

3. The method according to claim 1, characterized in that the coating is carried out on the bases of removable dentures, obturators and components of maxillofacial prostheses made of silicone materials;

4. The method according to claim 1, characterized in that the coating is carried out on the bases of removable dentures, obturators and components of maxillofacial prostheses made of thermoplastic materials;

5. The method according to claim 1, characterized in that the coating is carried out on the bases of removable dentures, obturators and components of maxillofacial prostheses made of polyurethane materials;

6. The method according to claim 1, characterized in that the coating is carried out on the metal parts of removable dentures, obturators and components of maxillofacial prostheses;

7. The method according to claim 1, characterized in that the artificial teeth or part of the bases of removable dentures, obturators and components of maxillofacial prostheses that do not require coating are pre-screened or protected with caps or plates made of thermoplastic materials, curved in the shape of the artificial teeth or bases of removable dentures, or obturators, or components of maxillofacial prostheses in a vacuumformer installation, or wrapped in a thin metal foil, or covered with an insulating varnish, while retainers are attached to them.

According to clause 10.7.4.3 (8) of the Requirements for the description of the invention [20]:

“... The signs used to characterize the ways.

To characterize the methods, the following features are used, in particular:

- the presence of an action or a set of actions;

- the order of performing actions in time,

- conditions for the implementation of actions; mode; use of substances, devices ... ".

A method of manufacturing bases of removable dentures (prototype) is used to form a coating on non-separable structures, namely bases with fixedly attached structural elements, in particular, metal. Such constructions constitute a single whole; the prototype method does not provide for the technological operation of assembling the device from separate structural elements, and the screwing of the screws in the claimed Method is carried out directly into the patient's bone tissue. This technological operation is necessary for the device to perform the function of fixing a bone fracture.

Denture bases and structural elements of prostheses are other medical devices used for other purposes and are not applicable for the treatment of bone fractures.

The structural elements of the device for fixing a bone fracture according to the proposed Method are processed separately, as separate elements, and then they are connected together. Thus, to obtain the technical result, an operation of assembling the device from individual elements is required, and directly on the patient's bone tissue. This is a necessary condition for the manufacture of the claimed device and a new set of essential features, which is necessary and sufficient to achieve the technical result.

Thus, the claimed Method has new essential features and significant differences from the Prototype Method.

The claimed Method is intended for the manufacture of the claimed Device, thus the claimed technical solution meets the requirement of unity of invention.

One of the essential features of the prototype method is the shielding of a part of the treated surface from the coating, in particular, the surface of artificial teeth, so that they remain the original white color. That is, the prototype method provides for the following operations:

- fixing screens and protecting part of the surface of the processed device,

- applying the coating not to the entire surface, but only to the unshielded part of the surface and

- subsequent removal of shielding elements and / or shielding coatings.

These essential features and their combination are inapplicable in the claimed method of manufacturing a device for fixing a bone fracture, since it is necessary to completely cover the entire surface of the structural elements of the device to achieve the technical result. This is only possible if the structural elements are processed separately, and then combined into a single structure. This confirms the significant differences between the two methods.

The method of manufacturing a device for fixing a bone fracture is carried out as follows:

a) maxillofacial plates and fasteners - the device screws are prepared for coating, if necessary, cleaned, washed, degreased;

b) clamps are attached to the structural elements of the device;

c) samples of structural elements of the device, fixed with clamps on holders, are placed on the pins of the carousel disk in the technological vacuum chamber of the ion-plasma treatment unit;

d) pump out atmospheric air from the volume of the technological vacuum chamber to a pressure not higher than P≈8-9 * 10 ^-3 Pa according to the indications of a commercially available vacuum gauge, in particular, VMB-14 with a PMM-32-1 sensor, which are used in industry, then eat until the required vacuum is created;

e) an accelerating voltage is applied to the electrodes of the ion-optical system of at least one source of accelerated particles, for example, II-4-0.15 ("Radical"), from a power source (unit), for example, BP-94. The ion source forms a partially neutralized ion beam, which can be neutralized, for example, by a space charge by 1-10%, and by a neutralization cathode by 100%;

f) a working gas is supplied through the leak valve or another device for precise metering of the gas flow of the inlet system into the discharge zone of the source of accelerated particles to clean the surface of the samples, for example, an inert gas, usually argon, until the working pressure is reached in the pressure range from P≈1.0 * 10 ^-2 Pa to P≈, 0 * 10 ^-1 Pa or a mixture of inert and chemically active gases, for example, an inert gas argon Ar - 80% and a reactive oxygen gas O ₂ -20%;

g) form at least one beam of accelerated particles of the working gas;

h) turn on the rotation of the carousel disc, and the structural elements of the device for fixing bone fractures begin to perform a planetary rotational movement, simultaneously rotating in the horizontal plane with the disc and around the vertical axis together with the pins;

i) cleaning and activating the surface of product samples for a given time, usually τ≈30-60 minutes, with a beam of accelerated particles, for example, inert gases, in particular argon Ar, or a mixture of inert and chemically active gases, for example, an inert gas argon Ar - 80% and reactive oxygen gas O ₂ - 20%;

j) stop cleaning and activation of the surface of product samples and stop supplying a working gas, that is, an inert gas or a mixture of gases, and start feeding an organosilicon compound in the gas phase and / or a mixture of compounds in the gaseous phase into the discharge zone of the source (or sources) of accelerated particles, which contains at least one organosilicon compound containing carbon (C) and silicon (Si) atoms in the molecule, for example, gaseous vapors of a liquid organosilicon compound;

k) supply voltage to the electrodes of the ion-optical system of the source (or sources) of accelerated particles;

m) the discharge is switched on, the gas molecules are ionized in the discharge gap of the source (or sources) of accelerated particles and a beam of accelerated particles with energies from 30 eV to 4 KeV is formed in the discharge zone from the molecules of the organosilicon compound, in particular, charged ions and / or neutral atoms and / or radicals containing silicon (Si) and carbon (C) in various combinations, charged ions Si _x C _y ⁺ and / or neutral radicals Si _x C _y ;

m) bombarding the surface of the workpiece with a beam (or beams) of accelerated particles, which contain ions and / or neutral particles, radicals of organosilicon compounds, as a result, a film of organosilicon compounds Si _x C _y is formed on the surface of structural elements of the device for fixing bone fractures;

n) a thin-film coating based on Si _x C _y is formed on the surface of the product samples by deposition from at least one beam of accelerated ions and / or neutral particles of an organosilicon compound, this occurs due to the dissociation of accelerated particles on the surface of the product containing silicon and carbon Si _x C _y ⁺ and / or Si _x C _y ;

n) where the minimum film thickness h _min corresponds to the layer thickness that depends on a specific product, for example, h _min ≈0.1 * 10 ^-6 m on the sample surface, while the process of forming a thin-film coating based on Si _x C _y on the surface of the product samples by deposition from a beam of accelerated particles, it can continue until a given film thickness required for a specific product is obtained, in particular, up to h≈0.8 * 10 ^-6 m;

p) after reaching the specified film thickness h, usually after τ≈30 minutes-10 hours, the process is stopped, the voltage supply to the electrodes of the ion-optical system of the source of accelerated particles, in particular, ions, is turned off (if a charge neutralizer is used, then the voltage supply is turned off to the charge neutralizer), stop the gas supply to the source of accelerated particles, close the shutter of the turbomolecular pump, let atmospheric air into the volume of the technological vacuum chamber, open the door of the technological vacuum chamber, remove the holders with products on the surface of which a silicon carbide coating is applied;

c) the extraal plate is installed directly on the bone tissue in the area of the bone fracture;

r) pass the fixing screws through the through holes of the plate,

y) screw the fixing screws into the bone tissue;

f) fix the position of the extraal plate relative to the bone fragments.

Examples of implementation of a Device for fixing a bone fracture and a Method for manufacturing this device.

At the end of 2018, more than 40 miniplate plates and more than 70 silicon carbide coated titanium alloy screws were manufactured. Coating thickness varied from 0.1-0.3 micrometers (0.1-0.3 × 10 ^-6 meters) to 0.6-0.8 micrometers (0.6-0.8 × 10 ^-6 meters ). The application was carried out with one and / or two sources of accelerated particles II-4.0-0.15 ("Radical"), the accelerating voltage was supplied through the power supply unit BP-94. Products (devices) were used in the course of maxillofacial operations for the treatment of fractures of the jaws in the District Hospital No. 2.

Operation No. 1 Case history of patient D

Patient G. was admitted for treatment on 12.11.2018.

COMPLAINTS at admission: pain in the lower jaw in the frontal part on the right, in the upper part of the parotid region on the right, painful opening of the mouth.

ANAMNESIS OF ILLNESS (according to the patient): considers himself ill from 3.11.18, when he was injured as a result of a fight. Was sober. I did not lose consciousness, there was no nausea or vomiting. He independently applied to the Volokolamskaya Central Regional Hospital, an X-ray of the skull bones in frontal and lateral projections was performed, on which a fracture of the lower jaw was found. On 12.11.18 the patient applied to ChLH RB # 2. After examination, he was hospitalized in XO-3 for urgent indications.

LOCAL STATUS on admission: an external examination determines the edema of the soft tissues of the parotid-masticatory region on the right and the chin region on the right. The skin is physiological in color. On palpation of the anterior wall of the external auditory canal during lowering, lifting and displacement towards the lower jaw, the movements of the articular heads are significantly limited, while the patient notes pain in these areas. The symptom of loading is positive in the area of the condylar process on the right and in the frontal part. In the oral cavity, there is a violation of the bite: there is no contact of the teeth in the frontal part - there is a gap of up to 0.6 cm, molars are in contact on both sides. The mucous membrane of the oral cavity is hyperemic, edematous. There is a rupture of the mucous membrane in the area of the teeth 4.1- 4.3

On the roentgenogram of the skull in frontal projection, a fracture of the condylar process on the right with displacement of fragments inward, a fracture of the lower jaw in the frontal region in the area of 4.1-4.3 teeth is determined.

Based on complaints, anamnesis, physical examination data,

DIAGNOSIS: Fracture of the condylar process of the lower jaw on the right and the body of the lower jaw in the area of teeth 4.1-.4.3 with displacement of fragments.

On November 14, 2018, a surgical intervention was performed under endotracheal anesthesia in the volume: reduction and osteosynthesis of the fragments of the lower jaw with titanium miniplates and screws coated with silicon carbide.

Operation # 1. Operation progress

Under endotracheal anesthesia with intubation of the trachea through the nose, the oral cavity was treated three times with 0.05% chlorhexidine bigluconate solution and three times the skin of the operating field was treated with an aqueous solution of iodopyrone 1%.

A skin incision was made, a 5 cm long incision was made, bordering the corner of the lower jaw on the right, 2 cm apart from the last. The tissues were dissected in layers to the base of the lower jaw. The chewing muscle was cut off and detached, the outer surface of the mandible branch was highlighted. In the depth of the wound, a fragment of the condylar process was found, which was isolated and set in the correct position. Bone fragments were compared and fixed with a titanium plate and 4 screws coated with silicon carbide. The wound was sutured in layers with interrupted sutures. The skin was sutured with polyamide thread, and a rubber drain was introduced into the wound. An aseptic bandage was applied.

Next, the mucous membrane of the body of the lower jaw was made on the right in the area of the teeth 3.2-4.4. The lower jaw was skeletonized in the area of the fracture, and the fracture line was revealed. Granulations were removed from the fracture line with a curette spoon. Reposition of bone fragments. Bone fragments were matched and fixed with a titanium plate and 4 screws coated with silicon carbide. The wound was sutured with catgut. Sanitation, hemostasis during the operation.

The operation and the postoperative period were normal. The patient was discharged with improvement on November 15, 2018.

Operation No. 2. Patient K's medical history

Patient K. was admitted for treatment on 12.11.2018.

COMPLAINTS at admission: pain and swelling in the lower jaw on the left, painful opening of the mouth, inability to chew food.

ANAMNESIS OF ILLNESS (according to the patient): considers himself ill for 2 weeks, when he hit the corner of the wall in alcoholic intoxication. There was no nausea or vomiting. I didn’t lose consciousness. There was no bleeding. I did not go to the doctor. The next day, painful swelling appeared in the lower jaw area on the left. He took Cephalexin on his own. The edema has slightly decreased. The pain persisted. On 12.11.18 I applied to the FGBU FNKTs FHM FMBA of Russia Clinical Hospital No. 123, Odintsovo, where an X-ray examination was performed. After that he was sent to the department of the ChLH RB # 2. After examination, he was hospitalized in XO-3 for urgent indications.

LOCAL STATUS on admission: On external examination: there is a slight swelling of soft tissues in the area of the corner of the lower jaw on the left. The skin over the edema is cyanotic in color, gathers freely in a fold, while there is a slight soreness in the corner of the lower jaw. On palpation of the base of the lower jaw and the branch on the left, traumatic edema is noted. Violations of the continuity of the base cannot be determined due to pronounced edema. The symptom of loading is sharply positive in the area of the lower jaw angle on the left. In the oral cavity: the bite is broken, there is no contact in the area of the premolars and molars on the left. The gum is torn along the transitional fold in the area of 3.8. When swaying, pathological mobility of the fragments of the lower jaw is noted in the area 3.8

On OPTG: Tooth 3.8 rests on the medial tubercles against the distal root of tooth 3.7. Resorption of bone tissue in the distal alveolar bone is noted.

Based on complaints, anamnesis, physical examination data,

DIAGNOSIS: Fracture of the lower jaw in the corner on the left with displacement of fragments.

On November 14, 2018, a surgical intervention was performed under endotracheal anesthesia in the amount of: reduction and osteosynthesis of fragments of the lower jaw with titanium miniplates and screws coated with silicon carbide, tooth extraction 3.8.

In the postoperative period, a course of antibacterial anti-inflammatory therapy (ceftriaxone 1.0 i / m 2 w.d.), a course of symptomatic therapy was carried out. Also in the postoperative period, there was a postoperative hematoma of the left buccal region. The course of the disease with positive dynamics. After the treatment, there was a clinical improvement.

The patient was discharged with improvement on November 15, 2018.

Operation No. 2. Operation progress

Under endotracheal anesthesia with intubation of the trachea through the nose, the oral cavity was treated three times with 0.05% chlorhexidine bigluconate solution and three times the skin of the operating field was treated with an aqueous solution of iodopyrone 1%.

An incision was made in the mucous membrane of the lower jaw body on the left in the area of the fracture. The mucoperiosteal flap was detached and folded back. Then, using a piezotome, an osteotomy was performed, part of the cortical plate covering the crown of tooth 3.8 was removed. The crown of tooth 3.8 is visualized, tooth 3.8 is removed with the help of an elevator. Curettage, antiseptic treatment.

Next, the lower jaw was skeletonized in the area of the fracture, and the fracture line was revealed. Granulations were removed from the fracture line with a curette spoon. Reposition of bone fragments. Bone fragments were matched and fixed with a titanium plate and 4 screws coated with silicon carbide. The wound was sutured with catgut. Sanitation, hemostasis during the operation.

Operation No. 3. Patient T's medical history

Patient T. was admitted for treatment and examined on 07.11.2018.

COMPLAINTS at admission: headache, pain in the lower jaw when throwing back the head and when chewing food.

ANAMNESIS OF DISEASE (according to the patient): considers herself ill from 5.11.18, when due to a household injury (falling from a ladder) she hit her chin on the floor. Was sober. After the nausea fell, there was no dizziness. She noted bleeding when bending her head down. I didn't lose consciousness. She turned to the State Budgetary Healthcare Institution of the Ministry of Regional Development of the Republic of Belarus, where she underwent an X-ray and prescribed drugs: Diacarb 1 t 3 r / day, Glycine 1 t 3 r / day. After that she was sent to the department of ChLH RB №2. After examination, she was hospitalized in XO-3 for urgent indications.

LOCAL STATUS on admission: The configuration of the face was changed due to edema of the soft tissues of the infraorbital, zygomatic and mandibular regions on the right and left. The skin over the edema is cyanotic, gathers freely in a fold, while slight soreness is noted. On palpation of the base of the lower jaw and the branch on the left, traumatic edema is noted. Violations of the continuity of the base cannot be determined due to pronounced edema. The symptom of loading is sharply positive in the area of the lower jaw angle on the left and right. The interpupillary line is uneven. Retraction of soft tissues in the zygomatic regions on the right and left. The stair symptom is positive on both sides. Palpation of the zygomatic regions on the right and left is sharply painful. In the oral cavity: opening of the mouth is difficult up to 2.5 cm. The gums are torn along the transitional fold in the area of the molars of the lower jaw on the right and left, hemorrhage into the mucous membrane and edema are noted. When rocking, pathological mobility of the fragments of the lower jaw in the region of the molars on the left and right is noted. In the sublingual region on the left, imbibition of the mucous membrane with blood and its edema are also noted.

Based on complaints, anamnesis, physical examination data,

DIAGNOSIS: Fracture of the zygomatic bone with displacement to the right and left. Fracture of the body of the lower jaw with displacement of fragments to the right and left. Fracture of the bottom of the orbit on the right. Bilateral hemosinus.

On November 12, 2018, a volume of surgical intervention was performed: reduction and osteosynthesis of the fragments of the lower jaw with titanium miniplates and screws coated with silicon carbide. In the postoperative period, a course of antibacterial anti-inflammatory therapy (ceftriaxone 1.0 i / m 2 w.d.), a course of symptomatic therapy was carried out. The course of the disease with positive dynamics. After the treatment, there was a clinical improvement. The patient was discharged with improvement on November 16, 2018.

Operation progress # 3

Under endotracheal anesthesia with intubation of the trachea through the nose, the oral cavity was treated three times with 0.05% chlorhexidine bigluconate solution and three times the skin of the operating field was treated with an aqueous solution of iodopyrone 1%.

An incision was made in the mucous membrane of the lower jaw body on the right in the area of the fracture. The lower jaw was skeletonized in the area of the fracture, and the fracture line was revealed. Granulations were removed from the fracture line with a curette spoon. Reposition of bone fragments. Bone fragments were matched and fixed with a titanium miniplate with a "Carapace" coating and 4 screws. The wound was sutured with catgut.

Next, an incision was made in the mucous membrane of the lower jaw body on the left in the area of the fracture. The lower jaw was skeletonized in the area of the fracture, and the fracture line was revealed. Granulations were removed from the fracture line with a curette spoon. Reposition of bone fragments. Bone fragments were juxtaposed and fixed with a titanium miniplate with "Armor" coating and 4 screws. The wound was sutured with catgut. Sanitation, hemostasis during the operation.

Graphic materials

FIG. 1. Schematic representation of a device for fixing a bone fracture (prototype).

FIG. 2. Schematic representation of the claimed device for fixing a bone fracture.

FIG. 3. Scheme for measuring the surface resistance of a sample of a stainless steel plate coated with a silicon carbide film.

FIG. 4. Appearance of the multifunctional voltmeter V7-40 and resistance box R35.

FIG. 5. External view of the MASTECH MS8222H multimeter and high-resistance resistances of the KEV-5, KVM brands.

FIG. 6. Scheme of measurements of the volume resistance of a stainless steel plate with a silicon carbide film deposited on the surface.

FIG. 7. Scheme of measurements of the volume resistance of a structure of two stainless steel plates with a silicon carbide film applied to the surface of each sample. The samples are in contact through a silicon carbide film.

FIG. 8. External view of the E6-3 teraohmmeter and holder with samples coated with a silicon carbide film.

FIG. 9. Graph of the energy distribution function of accelerated particles of ions and / or neutrals formed by the source II-4.0-0.15 ("Radical").

FIG. 10. Diagram of the discharge gap of the ion source [29].

FIG. 11. Graphs of distribution functions of atoms and ions [30]

FIG. 12. Graphs of distribution functions for various parameters of the fields [30].

FIG. 13. Graphs of the dependences of the distribution functions of He + ions [30].

FIG. 14. Graphs of the distribution functions of ions of individual mass numbers of CF ₄ gas by energy during the formation of the beam by the "Radical" source [28].

Information sources

1. Loukota R.A., Shelton J.C. Mechanical analysis of maxillofascial miniplates. Britisch Journal of Oral and Maxillofascial Surgery, 1995 (Vol. 33). - P / 174-179.

2. What are titanium plates used for in fractures? http://bezperelomov.com/obshee/titanovaya-plastina-pri-perelomax.html.

3. Removal of the plate, pins and screws after ankle fracture: surgery and rehabilitation period, http://nogostop.ru/golenostop/lodyzhka/udalenie-plasttiny-posle-pereloma-lodyzhki.html.

4. What is galvanism in dentistry: treatment, symptoms, photos. http://topdent.ru/articles/galvanism-v-polosti-rta/html.

5. Zaitseva A.G. Diagnostics and treatment of galvanism in the oral cavity. Abstract of the dissertation for the degree of candidate of medical sciences. St. Petersburg, 2005 http://dissercat.com/content/diagnostika-i-lechenie-galvanizma-v-polosti-rta.

6. Surgical dentistry from A to Z. Injuries of the MAP. Non-gunshot wounds of the ChLO. Osteosynthesis of the jaw, surgical methods of treating jaw fractures http://hirstom.ru/neognestrelnie-povrezhdeniya-chlo/osteosintez -chelusti-operativnie-metodi-lecheniya-perelomov-chelustey.

7. Grebenshchikova M.M., R.A. Nigmatullina R.A., Khaidarova L.M. Toxicity study of materials for orthopedics with coatings obtained by the ion-plasma method, https://cyberleninka.ru/article/v/issledovanie-toksichnosti-materialov-dlya-ortopedii-s-pokrytyami-poluchennymi-ionno-plasmennym-sposobom.

8. Korolev Ε. Titanium nanoparticles can cause cancer! - Notes of a provincial journalist-Forum orbita96.

9. Bronstein D.A. Fixed prosthetics in the complete absence of teeth using intraosseous implants in the anterior part of the jaw (clinical, biomechanical and economic aspects). Dissertation for the degree of Doctor of Medical Sciences. Moscow 2017.

10. Erubaev Ε.A. Cyclic deformation and thermomechanical stability of titanium and its alloys for medical use. Abstract of dissertation for the degree of candidate of technical sciences, Belgorod 2017

11. Abilev S.K., Glazer V.M. Mutagenesis with the basics of genotoxicology: study guide: - M .; SPb .: Nestor-Istoriya, 2015 .-- 304 pp. 178-179.

12. A method of obtaining an anodic-oxide coating on parts made of titanium alloys. RF patent No. 2383664. IPC class: C25D 11/26. Authors: Pivovarova L.N., Zakharova L.V., Fadeev A.V. Application filing 2009-03-31, patent publication 10.03.2010. http://www.freepatent.ru/patents/2383664.

13. GOST Ρ 51058-97 Metal dental prostheses with protective coatings. Technical conditions.

14. Application of titanium nitride to metal surfaces https://kvadra-tools.ru/a50966-nanesenie-nitrid-titana.html.

15. Technology. Vacuum spraying laboratory. http://n-titana.ru/technology

16. Starchenko T.P. Influence of dentures with titanium nitride coating on the morpho-functional state of the oral cavity and the upper segment of the gastrointestinal tract. Abstract of the dissertation for the degree of candidate of medical sciences. Krasnodar, 1996.http: //medical-diss.com/medicina/vliyanie-zubnyh-protezov-s-nitrid-tytanovim-pokrytiem-na-morfo-funktsionalnoe-sostoyanie-polosti-rta-i verhnego otrezka-z.

17. Extra bone plate for osteosynthesis. Copyright certificate No. 1502020 A1 dated 23.08.89. Bul. No. 31 Cl A61V 17/58. R.R. Khadzhaev and B.V. Shavarin.

18. Device for fixing a bone fracture. Patent of Belarus BY 3111 U dated 30.10.2006. Application number: and 20060199 from 03.04.2006.

19. Voronov I.A. Development, scientific substantiation and introduction into practice of coating with silicon nanocarbide of dentures and dentures. Dissertation for the degree of Doctor of Medical Sciences. Moscow 2016.

20. Administrative regulations for the execution by the Federal Service for Intellectual Property, Patents and Trademarks of the state function of organizing the receipt of applications for an invention and their consideration, examination and issuance in the prescribed manner of patents of the Russian Federation for an invention. Registered in the Ministry of Justice of the Russian Federation on February 20, 2009 Registration No. 13413.

21. GOST Ρ 50499-93 (IEC 93-80) Solid electrical insulating materials. Methods for determining the specific volume and surface resistance.

22. Conductors, dielectrics and electron flow. www.radiomexanik.spb.ru/1.-osnovvyi-elektroniki/2.-provodniki-dielektriki-i-potok-elektronov.html/

23. Chemist's Handbook (Internet)

24. Telesh E.V., Dostanko A.P., Vashurov A.Yu. Optical characteristics of thin silicon dioxide films obtained by direct deposition from ion beams. https: //cyberleninka.m/article/n/opticheskie-harakteristiki-tonkih-plenok-dioksida-krerrmiya-poluchermyh-pryam

25. Ion-plasma methods for the formation of thin-film coatings. https://otherreferats.allbest.ru/radio/00130398_0.html

26. I. V. Radchenko. Molecular Physics, Moscow: Nauka, 1965, 479 p. 34-35.

27. Revinskaya OG, Kravchenko N.S. Maxwell's distribution. Study guide. Tomsk: Publishing house of Tomsk Polytechnic University, 2012. - 33 p. From 11.

28. Mitrofanov E.A., Maishev Yu.P. Mass-spectrometric methods of control of technological processes of etching and formation of films .. Vacuum equipment and technology, 1992, Volume P. No. 4, S 59-68.

29. Broday I., Merey J. Physical foundations of microtechnology: Per. from English. - M .: Mir, 1985. - 496 p., Ill.

30. Mustafaev A.S., Sukhomlinov B.C., Ainov M. A. Experimental and theoretical determination of the strongly anisotropic ion velocity distribution function in the plasma of its own gas at high fields.- Journal of technical physics, 2015, volume 85, issue. 12, p. 45-55.

31. Chemist's Handbook (Internet).

32. Mass spectrometry in organic chemistry / А.Т. Lebedev. - M .: BINOM. Knowledge Laboratory, 2003. - 493 p., Ill. - (Methods in chemistry).

33. A method of forming a thin-film protective coating on the bases of removable dentures, obturators and components of maxillofacial prostheses. RF patent No. 2540227.

Claims (21)

1. A device for fixing a bone fracture, consisting of a plate with through holes and screws, characterized in that an ion-plasma coating of silicon carbide is applied to the entire surface of the plate, including the walls of the holes and fasteners of the screws, formed in vacuum by deposition from a beam of accelerated particles with an energy of 30 ± 5 eV to 4 ± 0.2 keV, containing silicon and carbon atoms, charged ions and / or neutral atoms and / or radicals, the thickness of the coating being in the range from 0.1 micrometer to 0.8 micrometer. 2. A method of manufacturing a device for fixing bone fractures according to claim 1, wherein: a) preliminary preparation of the surface of individual structural elements of the device for fixing a bone fracture, for example, washing, degreasing, b) loading of preliminary prepared samples of structural elements of the device for fixing bone fractures into the volume of the technological vacuum chamber of the ion-plasma treatment unit, c) pumping out air from the volume of the technological vacuum chamber to a pressure below atmospheric, and not higher than P≈8-9 * 10 ^-3 Pa, d) supplying the discharge zone of the ion source to the working pressure from P≈1.0 * 10 ^-2 Pa to P≈1.0 * 10 ^-1 Pa of the working gas, which is used as an inert gas and / or a reactive gas, and / or a mixture of inert and reactive gases, e) supplying a voltage ion source to the electrodes of the ion-optical system, while turning on the discharge, ionizing the atoms and molecules of the working gas and forming a beam of accelerated ions of inert gases and / or ions of chemically active gases, and / or ions of mixtures of inert and chemically active gases, f) cleaning the surface of product samples and activating it with a beam of accelerated positive ions, g) stopping the supply of working gas for cleaning the surface of the prostheses, h) supplying an ion source of an organosilicon compound and / or a mixture of compounds in the gas phase, which contains at least one organosilicon compound, to the discharge zone, containing carbon (C) and silicon (Si) atoms in the molecule, at an operating pressure of P = 1.0 * 10 ^-2 Pa to P = 1.0 * 10 ^-1 Pa, i) supplying a voltage ion source to the electrodes of the ion-optical system, while turning on the discharge, ionizing the atoms and molecules of the organosilicon compound in the gaseous phase in the discharge zone and forming a beam of accelerated ions, which include carbon (C) and silicon (Si) atoms , j) obtaining a film with a thickness of h _min = 2.5 * 10 ^-10 m or a thickness from h = 1.0 * 10 ^-10 m to h = 1.0 * 10 ^-6 m, characterized in that l) voltage is applied to the electrodes of the ion-optical system of the source of accelerated particles, while the discharge is switched on, the atoms and molecules of the organosilicon compound in the gaseous phase in the discharge zone are ionized and a beam of accelerated particles is formed: ions and / or neutral particles with an energy of 30 ± 5 eV up to 4 ± 0.2 keV, which include carbon (C) and silicon (Si) atoms, m) carry out obtaining on the entire surface of each of the products a silicon carbide film with a thickness from h = 0.1 * 10 ^-6 m to h = 0.8 * 10 ^-6 m, m) disconnect the accelerating voltage, stop the supply of the working gas for coating, close the shutter of the high-vacuum pump, let atmospheric air into the volume of the process chamber, remove the structural elements of the device for fixing the bone fracture with a silicon carbide coating on the entire surface, o) apply a silicon carbide coated plate directly to the bone tissue in the fracture area, n) screw the fastening screws coated with silicon carbide through the through holes of the plate into the bone tissue, p) fix the position of the plate and bone fragments using fasteners.

Images