CN114099081A - Medical magnesium alloy bone implant particles and preparation method - Google Patents

Abstract

The invention provides medical magnesium alloy bone implantation particles and a preparation method thereof. The sealing balls are multiple, and the diameter of each sealing ball is larger than that of the base ball; the diameters of the sealing balls are sequentially increased in an increasing mode, and the sealing balls and the base ball are arranged concentrically; the supporting rods are arranged in plurality and are uniformly distributed on the base ball and the sealing ball; each supporting rod is provided with two end parts, wherein one end part is positioned at the center of the base ball, and the other end part sequentially penetrates through the sealing balls along the radius direction of the base ball and extends out of the sealing ball with the largest diameter; the spherical porous layer is sleeved outside the sealing ball with the largest diameter and is fixedly connected with the other end of each supporting rod. The invention provides medical magnesium alloy bone implant particles and a preparation method thereof, aiming at solving the problems of poor adaptability and practicability caused by the fact that the degradation rate of the existing medical magnesium alloy implant is high and the degradation time cannot be regulated.

Description

Medical magnesium alloy bone implantation particles and preparation method thereof

Technical Field

The invention belongs to the technical field of bone scaffold material construction, and particularly relates to medical magnesium alloy bone implantation particles and a preparation method thereof.

Background

Large-area bone defect is generated due to congenital malformation, bone diseases, bone trauma and the like, and serious harm is generated to human bodies. Since the affected part can not be recovered by self healing, the affected part is often repaired or replaced by matching the medical implant through an operation. The traditional treatment method repairs through autologous bone transplantation, but the autologous bone is limited in material obtaining and needs to be additionally operated to take bones, so that bleeding and infection of the postoperative bone taking area are easily caused, and the pain of a patient is aggravated; although the allogeneic bone has wide sources, the allogeneic bone has the defects of disease transmission, immune response induction, poor bone healing and the like. Therefore, the medical magnesium alloy implant is widely applied due to the degradable function.

In the prior art, medical magnesium alloy has a high corrosion rate in a body fluid environment, and the implant often fails prematurely. Therefore, the surface of the magnesium alloy implant is usually coated with a polymer coating and an inorganic coating to regulate the degradation rate of the alloy and improve the biocompatibility. Although the improved structure can prolong a certain degradation rate, the degradation time of the magnesium alloy implant is still relatively fast compared with the self repair rate of a human body, and further the magnesium alloy implant cannot adapt to a part of the human body. Therefore, the existing medical magnesium alloy implant has the advantages of high degradation rate, incapability of regulating and controlling degradation time, poor adaptability and poor practicability.

Disclosure of Invention

The embodiment of the invention provides medical magnesium alloy bone implantation particles and a preparation method thereof, aiming at solving the problems of poor adaptability and practicability caused by the fact that the degradation rate of the existing medical magnesium alloy implant is high and the degradation time cannot be regulated.

In order to achieve the purpose, the invention adopts the technical scheme that: provides medical magnesium alloy bone implantation particles and a preparation method thereof, wherein the medical magnesium alloy bone implantation particles comprise:

a base ball;

the sealing balls are provided with a plurality of spherical cavities, and the diameter of each sealing ball is larger than that of the base ball; the diameters of the sealing balls are sequentially increased in an increasing mode, the sealing balls are concentrically arranged with the base ball, and a sealing cavity is formed between any two adjacent sealing balls;

a plurality of support rods are arranged, and each support rod is uniformly distributed on the base ball and the sealing ball; each supporting rod is provided with two end parts, wherein one end part is positioned at the center of the base ball, and the other end part sequentially penetrates through the sealing balls along the radius direction of the base ball and extends out of the sealing ball with the largest diameter; and

the spherical porous layer is sleeved outside the sealing ball with the largest diameter and is fixedly connected with the other end of each supporting rod; the spherical porous layer is provided with a plurality of holes for eliminating the stress shielding effect.

In one possible implementation, the wall thickness of each sealing ball increases in sequence from the sealing ball with the smallest diameter to the sealing ball with the largest diameter.

In one possible implementation manner, each support rod is of a stepped shaft type appearance structure; the diameter of one end, located at the base ball, of each supporting rod is smaller than that of the extending end of each supporting rod.

In one possible implementation, each support rod is integrally connected with the base ball and each sealing ball.

In one possible implementation, the base sphere is a hollow structure.

In one possible implementation, the pores on the spherical porous layer are triangular pores.

The invention also aims to provide a preparation method of the medical magnesium alloy bone implantation particles, which comprises the following steps:

preparing raw materials, namely preparing Mg-1Zn-0.5Gd alloy powder by mixing pure Mg powder, Mg-5Zn master alloy powder and Mg-15Gd master alloy powder;

test piece testing, namely manufacturing a test piece, putting the test piece into a simulation liquid, and testing whether the corrosion rate meets the requirement;

designing and modeling, designing the medical magnesium alloy bone implant particles as claimed in any one of the claims 1 to 6 to determine parameters of the base ball, each of the sealing balls, each of the support rods and the spherical porous layer, and drawing a model of the medical magnesium alloy bone implant particles; and

printing and manufacturing, namely placing the Mg-1Zn-0.5Gd alloy powder prepared in the raw material preparation step into a closed box, introducing inert gas into the closed box, and forming the Mg-1Zn-0.5Gd alloy powder at a first scanning speed by using a first power laser so as to print and prepare the medical magnesium alloy bone implantation particles drawn in the design modeling.

In one possible implementation, the inert gas is argon;

the printing and manufacturing adopts a 3D printer, wherein the first power is 95W, and the first scanning speed is 350 mm/s.

The medical magnesium alloy bone implantation particles provided by the invention have the beneficial effects that: compared with the prior art, the medical magnesium alloy bone implant particle has the advantages that the sealing balls with the spherical cavities are arranged, the sealing balls and the base ball are concentrically arranged, the diameters of the sealing balls are sequentially increased, the sealing cavity is formed between any two adjacent sealing balls, and the corrosion rate and the residual mechanical property of the medical magnesium alloy bone implant particle are regulated and controlled by regulating and controlling the number of the sealing layers. A plurality of supporting rods are arranged, the supporting rods are uniformly distributed on the base ball and the sealing ball, and the rod diameter of each supporting rod determines the corrosion failure time of the medical magnesium alloy bone implant particles. The spherical porous layer is provided with a plurality of holes, and the hole structure can lead cells to climb and grow to the inside of the medical magnesium alloy bone implant particles, so that the magnesium alloy bone implant particles are melted with the human body structure, the elastic modulus can be reduced, the stress shielding effect is eliminated, and the practicability is strong.

Drawings

Fig. 1 is a schematic structural diagram of medical magnesium alloy bone implant particles provided by an embodiment of the invention;

FIG. 2 is a schematic structural diagram of a spherical porous layer provided in an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a supporting rod according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a sealing ball provided in an embodiment of the present invention;

fig. 5 is a schematic view of a plugging structure according to an embodiment of the present invention.

Description of reference numerals: 10. medical magnesium alloy bone implant particles; 11. a spherical porous layer; 12. a support bar; 13. a sealing ball; 14. and (4) a plugging structure.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It should be noted that the terms "length," "width," "height," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "head," "tail," and the like, indicate orientations or positional relationships that are based on the orientations or positional relationships illustrated in the drawings, are used for convenience in describing the invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore should not be construed as limiting the invention.

It is also noted that, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," "disposed," and the like are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other suitable relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Further, "plurality" or "a plurality" means two or more unless specifically limited otherwise.

Referring to fig. 1 to 5 together, the medical magnesium alloy bone implant particles and the preparation method thereof according to the present invention will now be described. The medical magnesium alloybone implant particle 10 comprises a base ball, asealing ball 13, asupport rod 12 and a sphericalporous layer 11.

Thesealing ball 13 is provided in plurality. Each of thesealing balls 13 has a spherical cavity, and the diameter of each of thesealing balls 13 is larger than that of the base ball. The diameters of thesealing balls 13 are increased in sequence, thesealing balls 13 are arranged concentrically with the base ball, and a sealing cavity is formed between any twoadjacent sealing balls 13.

A plurality ofsupport rods 12 are arranged, and all thesupport rods 12 are uniformly distributed on the base ball and thesealing ball 13. Eachsupport rod 12 has two ends, one of which is located at the center of the base ball, and the other of which sequentially passes through therespective sealing balls 13 in the radial direction of the base ball and protrudes outside thesealing ball 13 having the largest diameter.

The sphericalporous layer 11 is sleeved outside thesealing ball 13 with the largest diameter and is fixedly connected with the other end of each supportingrod 12. The sphericalporous layer 11 is provided with a plurality of holes for eliminating the stress shielding effect.

Compared with the prior art, the medical magnesium alloy bone implantation particles provided by the embodiment of the invention have the advantages that the plurality of sealing balls with spherical cavities are arranged, the sealing balls and the base ball are concentrically arranged, the diameters of the sealing balls are sequentially increased, the sealing cavity is formed between any two adjacent sealing balls, and the corrosion rate and the residual mechanical property of the medical magnesium alloy bone implantation particles are regulated and controlled by regulating and controlling the number of the sealing layers. A plurality of supporting rods are arranged, the supporting rods are uniformly distributed on the base ball and the sealing ball, and the rod diameter of each supporting rod determines the corrosion failure time of the medical magnesium alloy bone implant particles. The spherical porous layer is provided with a plurality of holes, and the hole structure can lead cells to climb and grow to the inside of the medical magnesium alloy bone implant particles, so that the magnesium alloy bone implant particles are melted with the human body structure, the elastic modulus can be reduced, the stress shielding effect is eliminated, and the practicability is strong.

It should be noted that the stress shielding effect is that when two materials with different elastic moduli are put together and subjected to a force, the material with the larger elastic modulus carries a larger stress. Because the elastic modulus of the magnesium alloy is far greater than that of human bones, the medical magnesium alloybone implant particles 10 bear more stress action after being implanted into human bodies, human bones cannot be exercised, and growth and recovery of new bones are not facilitated, so that a plurality of holes for eliminating the stress shielding effect are arranged on the sphericalporous layer 11.

In some embodiments, referring to fig. 1, as the diameter of the sealingball 13 increases, the wall thickness of the sealingball 13 increases. In the embodiment, the corrosion rate and the residual mechanical property of the medical magnesium alloybone implant particles 10 are controlled by regulating and controlling the number and the thickness of the sealingballs 13.

As a specific embodiment of the examples of the present invention, the base sphere had a diameter of 4.1mm and a layer thickness of 400 μm. The sealingball 13 and the base ball are concentrically arranged, the sealingball 13 is sleeved inside the medical magnesium alloybone implantation particle 10 layer by layer, the diameter is 13.5mm and 8.6mm from outside to inside respectively, and the layer thickness is 800 μm and 600 μm respectively.

In some embodiments, referring to fig. 4, two taper holes are symmetrically formed on the surface of the sealingball 13, the diameter of the taper hole is 400 μm, and the taper is 30 °. In this embodiment, a taper hole is provided on the surface of the sealingball 13, and the residual powder in the sealingball 13 is removed through the taper hole.

In some embodiments, referring to fig. 5, the medical magnesium alloybone implant particle 10 provided by the embodiment of the present invention further includes a blockingstructure 14, where the blockingstructure 14 is adapted to the tapered hole on the surface of the sealingball 13, and is used to fill the tapered hole on the surface of the sealingball 13. In this embodiment, the pluggingstructure 14 is used to plug the taper hole on the surface of the sealingball 13, so that when the sealingball 13 is not corroded, the supportingrod 12 in the cavity of the sealingball 13 is prevented from being corroded, and the corrosion rate of the medical magnesium alloybone implantation particles 10 is controlled.

In some embodiments, referring to fig. 1 and 3, eachsupport rod 12 has a stepped shaft-type configuration. The diameter of eachsupport rod 12 at one end of the base ball is smaller than the diameter of the extending end of thesupport rod 12. In this embodiment, each of thesupport rods 12 has a stepped shaft-shaped configuration, and the diameter of the end of eachsupport rod 12 located at the base ball is smaller than the diameter of the extended end of thesupport rod 12, so that the corrosion rate and the residual mechanical properties of the medical magnesium alloybone implant particles 10 are controlled according to the rod diameter adjustment of different portions of eachsupport rod 12.

As a specific implementation manner of the embodiment of the present invention, eachsupport rod 12 has a stepped shaft-shaped configuration, and the outer diameters of the support rods are 800 μm, 600 μm, 400 μm, and 200 μm, respectively.

In some embodiments, referring to fig. 1, thesupport rods 12 are integrally formed with the base ball and the sealingballs 13. In this embodiment, after the sealingball 13 is damaged by corrosion layer by layer, the rod diameter outside the sealingball 13 is close to the rod diameter inside the sealingball 13, the sealingball 13 slows down the corrosion of the supportingrod 12 inside the cavity, and the residual mechanical properties of the medical magnesium alloybone implant particles 10 are improved.

In some embodiments, referring to fig. 1, the base sphere has a hollow structure.

In some embodiments, referring to fig. 1 and 2, the holes of sphericalporous layer 11 are triangular holes, which enhances the structural stability of sphericalporous layer 11.

Based on the same inventive concept, the embodiment of the application also provides a preparation method of the medical magnesium alloy bone implantation particles, which comprises the following specific steps:

s100, preparing raw materials, namely preparing Mg-1Zn-0.5Gd alloy powder by mixing pure Mg powder, Mg-5Zn intermediate alloy powder and Mg-15Gd intermediate alloy powder.

The particle size range of the Mg-1Zn-0.5Gd alloy powder is 15 to 53 mu m.

S200, testing the test piece, manufacturing the test piece, and putting the test piece into the simulation liquid to test whether the corrosion rate meets the requirement.

The test specimens were designed to have dimensions of 10mm by 3 mm. The edge of the test specimen is provided with a through hole with the distance of 1mm, and the through hole is used for hanging cotton threads. By the formula V ═ W-W₁) The average corrosion rate after immersion in the simulated solution for 72 hours was calculated.

Wherein V is the average corrosion rate of Mg-1Zn-0.5Gd alloy, and the unit is Mg/cm²A/day; w is the weight of the test piece before soaking, and the unit is mg; w₁The weight of the test piece after soaking is mg; a is the surface area of the test piece before soaking, and the unit is cm²(ii) a And T is the immersion time of the test piece in the simulation liquid, and the unit is d.

The average corrosion rate of the Mg-1Zn-0.5Gd alloy powder in 72 hours of soaking is 14.933Mg/cm²/day。

The surface area and the volume of the medical magnesium alloybone implantation particle 10 are calculated in CAD software, and the theoretical corrosion failure time of each structure of the medical magnesium alloybone implantation particle 10 is calculated.

S300, designing the medical magnesium alloybone implantation particle 10 to determine parameters of the base ball, the sealingballs 13, thesupport rods 12 and the sphericalporous layer 11, and drawing a model of the medical magnesium alloybone implantation particle 10.

And respectively establishing three-dimensional models of the base ball, the sealingball 13, the supportingrod 12 and the sphericalporous layer 11 in Solidworks software according to the calculated parameters, and combining the models of the base ball, the sealingball 13, the supportingrod 12 and the sphericalporous layer 11 through a Boolean summation function to form the medical magnesium alloybone implant particle 10. Exporting the designed model of the medical magnesium alloybone implantation particles 10 into an STL format file, and carrying out processing operations such as support adding, slicing and the like on the model of the medical magnesium alloybone implantation particles 10 in Magics software.

S400, printing, namely placing the Mg-1Zn-0.5Gd alloy powder prepared in the raw material preparation step into a closed box, introducing inert gas into the closed box, and forming the Mg-1Zn-0.5Gd alloy powder at a first scanning speed by using first power laser to print and prepare the medical magnesium alloybone implantation particles 10 drawn in the design modeling.

Before forming, placing Mg-1Zn-0.5Gd alloy powder prepared in the raw material preparation step in a closed box, introducing inert gas (serving as protective gas) into the closed box, reducing the oxygen content to be below 7000ppm, screening out powder with the particle size of more than 60 mu m and impurities by using a vibrating screen, and introducing the file obtained in S300 into an equipment host to generate a laser processing path. And in the forming process, introducing inert gas into the closed box to reduce the oxygen content to be below 250ppm, and printing and forming the magnesium alloy powder by using a first power laser at a first scanning speed.

In some embodiments, the inert gas is argon. The printing manufacture adopts a 3D printer, wherein the first power is 95W, and the first scanning speed is 350 mm/s.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims (8)

1. The medical magnesium alloy bone implant particles are characterized by comprising the following components:

a base ball;

the sealing balls are provided with a plurality of spherical cavities, and the diameter of each sealing ball is larger than that of the base ball; the diameters of the sealing balls are sequentially increased in an increasing mode, the sealing balls are concentrically arranged with the base ball, and a sealing cavity is formed between any two adjacent sealing balls;

a plurality of support rods are arranged, and each support rod is uniformly distributed on the base ball and the sealing ball; each supporting rod is provided with two end parts, wherein one end part is positioned at the center of the base ball, and the other end part sequentially penetrates through the sealing balls along the radius direction of the base ball and extends out of the sealing ball with the largest diameter; and

the spherical porous layer is sleeved outside the sealing ball with the largest diameter and is fixedly connected with the other end of each supporting rod; the spherical porous layer is provided with a plurality of holes for eliminating the stress shielding effect.

2. The medical magnesium alloy bone implant particles according to claim 1, wherein the wall thickness of each of the sealing balls increases in order from the sealing ball with the smallest diameter to the sealing ball with the largest diameter.

3. The medical magnesium alloy bone implant particles according to claim 1, wherein each of the support rods has a stepped shaft-shaped configuration; the diameter of one end, located at the base ball, of each supporting rod is smaller than that of the extending end of each supporting rod.

4. The medical magnesium alloy bone implant particles according to claim 3, wherein each of the support rods is integrally connected with the base ball and each of the sealing balls.

5. The medical magnesium alloy bone implant particle according to claim 1, wherein the base sphere has a hollow structure.

6. The medical magnesium alloy bone implant particle according to claim 1, wherein the pores on the spherical porous layer are triangular pores.

7. The preparation method of the medical magnesium alloy bone implantation particles is characterized by comprising the following steps:

preparing raw materials, namely preparing Mg-1Zn-0.5Gd alloy powder by mixing pure Mg powder, Mg-5Zn master alloy powder and Mg-15Gd master alloy powder;

test piece testing, namely manufacturing a test piece, putting the test piece into a simulation liquid, and testing whether the corrosion rate meets the requirement;

designing and modeling, designing the medical magnesium alloy bone implant particles as claimed in any one of the claims 1 to 6 to determine parameters of the base ball, each of the sealing balls, each of the support rods and the spherical porous layer, and drawing a model of the medical magnesium alloy bone implant particles; and

printing and manufacturing, namely placing the Mg-1Zn-0.5Gd alloy powder prepared in the raw material preparation step into a closed box, introducing inert gas into the closed box, and forming the Mg-1Zn-0.5Gd alloy powder at a first scanning speed by using a first power laser so as to print and prepare the medical magnesium alloy bone implantation particles drawn in the design modeling.

8. The method for preparing magnesium alloy bone implant particles for medical use according to claim 7, wherein the inert gas is argon;

the printing and manufacturing adopts a 3D printer, wherein the first power is 95W, and the first scanning speed is 350 mm/s.

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