CN114569223A

CN114569223A - Body implant with filler and method for the production thereof

Info

Publication number: CN114569223A
Application number: CN202210087616.1A
Authority: CN
Inventors: 杨玮; 宫海波; 肖杰
Original assignee: Suzhou Zhuoqia Medical Technology Co ltd
Current assignee: Suzhou Zhuoqia Medical Technology Co ltd
Priority date: 2022-01-25
Filing date: 2022-01-25
Publication date: 2022-06-03
Anticipated expiration: 2042-01-25
Also published as: CN114569223B

Abstract

A body implant with filler, comprising: peripheral structure, skeleton texture, filler and injection port. The framework structure comprises a plurality of supporting walls, wherein the supporting walls are mutually spliced to form a honeycomb-shaped structure with an upper top surface and a lower bottom surface; the supporting wall is a porous net structure; the supporting walls positioned at the edges of the framework structures are connected with the peripheral structures, an upper top surface and a lower bottom surface which are communicated are formed in the space surrounded by the peripheral structures and the framework structures, and the filling space which is sealed at the periphery is used for containing the filler. The injection port is arranged on the peripheral structure or the skeleton structure and is used for injecting filler. The invention also discloses a preparation method of the body implant, which comprises the steps of processing and connecting the peripheral structure and the skeleton structure, injecting filler and sintering at low temperature. The body implant disclosed by the invention has excellent mechanical properties, generates less gas during degradation, and has excellent biological activity and osteogenic induction capability.

Description

Body implant with filler and method for the production thereof

Technical Field

The invention relates to the field of medical instruments, in particular to a body implant with a filler for manufacturing a medical instrument and a preparation method thereof.

Background

The honeycomb structure originates from bionics, is a combined structure which is provided with regular hexagons without gaps, has excellent mechanical properties of light weight, small density, high strength, good rigidity, impact resistance and the like, and is widely applied to the aspects of building materials, aerospace manufacturing, transportation equipment and the like. For example, patent CN201710428356.9 discloses a magnesium alloy helmet using honeycomb reinforcing ribs, and the invention adopts a magnesium alloy framework with a honeycomb structure, so as to greatly reduce the weight of the helmet framework on the basis of good impact resistance. If the characteristics of the honeycomb structure are utilized in the field of medical appliances, some metal materials with bioactivity or degradability, such as pure magnesium, magnesium-zinc alloy and the like, are made into the honeycomb structure and then are utilized to make the corresponding medical appliances, so that the consumption of metal can be greatly reduced, and the mechanical strength of the honeycomb structure can be ensured.

However, for some degradable medical devices to be implanted into the body, the honeycomb structure can lead to the accelerated degradation and premature failure of the device, and the pure metal honeycomb structure is not favorable for the regeneration of blood vessels and tissues. When a bioactive material is filled into the honeycomb structure, the above-mentioned problems can be solved, but the filler is discontinuous in the honeycomb structure, and it is difficult to maintain a certain bonding strength with the honeycomb structure.

Disclosure of Invention

In view of the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a body implant with excellent biomechanical properties and both bioactivity and osteogenic induction ability.

To achieve the above object, the present invention provides a body implant with a filler, comprising: a peripheral structure; the framework structure comprises a plurality of supporting walls, and the supporting walls are spliced with each other to form a honeycomb-shaped structure with an upper top surface and a lower bottom surface; the supporting wall is a porous net structure; the supporting walls positioned at the edges of the framework structures are connected with the peripheral structures, and in the space surrounded by the peripheral structures and the framework structures, a filling space with communicated upper top surface and lower bottom surface and closed periphery is formed; the filler is used for filling the filling space formed after the outer supporting wall of the peripheral structure is connected with the framework structure; and the injection port is arranged on the peripheral structure or the skeleton structure and is used for injecting the filler into the filling space.

Furthermore, the materials of the peripheral structure and the framework structure are both metal magnesium or magnesium alloy.

Further, the thickness of the supporting wall is 0.3-3 mm, and the diameter range of the mesh of the porous mesh structure of the supporting wall is 0.1-0.5 mm.

Further, the filler is a porous structure.

Further, the filler is bone cement.

Further, the peripheral structure further comprises an outer support wall and an outer sealing plate; the outer supporting wall is connected with the side face of the framework structure, and the outer sealing plates are connected with the upper top face and the lower bottom face of the framework structure and are connected with the outer supporting wall simultaneously, and the framework structure is sealed.

Furthermore, the injection ports are reserved at four corners and the central position of the outer sealing plate.

The invention also provides a preparation method for preparing the body implant, which comprises the following steps: processing and connecting the peripheral structure and the framework structure to form a filling space with a honeycomb structure; injecting a filler, injecting the filler into a filling space through an injection port after the filler is pre-adjusted to be in a flowable state, and then standing and curing the honeycomb structure into which the filler is injected; and (3) low-temperature sintering, namely heating the whole solidified honeycomb structure to 250-450 ℃ for low-temperature sintering to obtain the body implant.

Further, in the step of injecting the filler, the injection pressure is set to be 0.2-0.6 MPa, the injection time is controlled within 30 minutes, the filling rate of the filler is controlled to be 80-99%, and the standing and curing time is 1-2 hours.

Furthermore, in the step of low-temperature sintering, the heat preservation time is 30-120 min.

The advantages of the body implant of the present invention are the following:

(1) the body implant with the filler of the present invention can reduce the amount of the degradable metal material used, and improve the strength and rigidity. When the metal material is degradable material such as magnesium or magnesium alloy, the bone cement filler can prolong the degradation time of the honeycomb structure and reduce the gas generated during degradation.

(2) The inner side plate is designed to be net-shaped, so that the filler can flow in the skeleton structure, and the injection pressure during injection is reduced. Meanwhile, the filler forms a continuous state after being cured, on one hand, after the framework structure is degraded, the filler can maintain a whole body without being broken, and the stability of the honeycomb structure is ensured; on the other hand, the adhesive force between the filler and the skeleton structure is improved, so that even if the body implant with the filler is processed into various shapes, certain mechanical property can be ensured, and the filler cannot fall off.

(3) By adopting the preparation method of the invention and low-temperature sintering, the bone cement can be used as a filler to be filled into a honeycomb structure made of magnesium or magnesium alloy, the internal stress of the magnesium or magnesium alloy is reduced, and the bone cement can be sintered into a porous filler. And thereby, the excellent mechanical property and biochemical property of magnesium or magnesium alloy can be utilized, and the function of guiding blood vessels and tissue regeneration of bone cement can be utilized.

Drawings

FIG. 1 is a schematic view of a honeycomb structure of the present invention.

Fig. 2 is a schematic view of the honeycomb of the present invention with the upper base plate removed.

Detailed Description

The technical means adopted by the invention to achieve the predetermined object of the invention are further described below with reference to the drawings and the preferred embodiments of the invention.

As shown in fig. 1 and 2, the body implant with filler according to the present invention comprises a peripheral structure 1, a skeletal structure 2, a filler 3 and an injection port 4. Wherein the peripheral structure 1 is connected with the framework structure 2, and an upper top surface, a lower bottom surface and a filling space with sealed periphery are formed in the space surrounded by the peripheral structure and the framework structure. The filler 3 is used to fill the filling space. The injection ports 4 are provided on the peripheral structure 1 or the skeletal structure 2 near or at the upper top surface and/or the lower bottom surface of the skeletal structure for injecting the filler 3 into the filling space.

In the preferred embodiment of the invention, the peripheral structure 1 comprises a plurality of outer support walls 11 and two outer closure plates 12. As shown in fig. 1, the outer supporting walls 11 are spliced into a prism structure with a closed periphery and a hollow middle. The two outer sealing plates 12 are connected with the plurality of outer supporting walls 11, and the upper top surface and the lower bottom surface of the prism structure formed by splicing the outer supporting walls 11 are sealed.

In the preferred embodiment of the invention, the skeletal structure 2 comprises a plurality of support walls 21. As shown in fig. 1, a plurality of supporting walls 21 are joined to each other to form a skeleton structure 2 having a honeycomb structure on the upper and lower top surfaces. As shown in fig. 2, the upper surface and the lower surface of the framework structure 2 are connected. The framework structure 2 is arranged in a hollow prism surrounded by the peripheral structure 1, the supporting wall 21 at the edge is connected with the outer supporting wall 11, the two outer sealing plates 12 are respectively connected with the upper top surface and the lower bottom surface of the framework structure 2, and the supporting wall 21 is completely vertical to the outer sealing plates 12. Wherein the supporting wall 21 is a porous net structure with a thickness of 0.3-3 mm. The shape of the mesh 210 on the support wall 21 is circular, the aperture is 0.1-0.5 mm, and the shape of the mesh 210 is not limited thereto, and can be designed to be polygonal such as square, triangle, etc. The mesh of the supporting walls 21 improves the flowability of the filling 3 during filling, facilitating filling of the filling, while ensuring that the filling 3 assumes a continuous state in the skeleton structure 2, whereby the filling 3 remains integral without breaking even if the skeleton structure 2 degrades. On the other hand, the mesh design of the supporting wall 21 is also beneficial to improving the adhesive force between the filler 3 and the skeleton structure 2, thereby improving the mechanical property of the honeycomb structure and being beneficial to manufacturing the honeycomb structure into various shapes.

In a preferred embodiment of the present invention, the material of the skeleton structure 2 may be a degradable metal material, preferably a pure magnesium or magnesium alloy material, because pure magnesium or magnesium alloy has good biomechanical compatibility, biodegradability, bioactivity and osteoinductivity, and its elastic modulus is closer to that of normal bone tissue than the currently commonly used implant material, so as to avoid the influence of stress shielding effect on new bone generation and shaping, and simultaneously, magnesium ions can stimulate the generation of hard callus at the fracture end, induce bone formation, promote fracture healing and stimulate cartilage generation.

In the preferred embodiment of the present invention, the filler 3 is a porous structure, which is advantageous for the generation of tissues such as blood vessels in the filler. Preferably, the filler is degradable bone cement, because the bone cement has the advantages of self-curing, strong plasticity and good bioactivity, and has the function of guiding blood vessels and tissue regeneration. Wherein the degradable bone cement comprises: calcium phosphate bone cement, magnesium phosphate bone cement or bone cement compounded by calcium phosphate bone cement and magnesium phosphate bone cement.

In the preferred embodiment of the present invention, as shown in fig. 1, the injection port 4 is disposed at the four corners and the center of the upper and lower outer sealing plates 12, so that the gravity can promote the filler to flow in the skeleton structure 2, thereby facilitating the injection of the filler.

In another aspect, the present invention also relates to a method of making a preferred embodiment of the present invention, comprising:

the method comprises the following steps: the peripheral structure 1 and the framework structure 2 are processed by magnesium or magnesium alloy, and the peripheral structure 1 and the framework structure 2 are connected and built into a honeycomb structure with closed periphery and filled space.

Step two: and injecting the filler 3, namely mixing and stirring the filler 3, namely the bone cement, injecting the mixture into a filling space formed by the peripheral structure 1 and the framework structure 2 through five injection ports 4 on the upper outer sealing plate 12, and standing and curing for 1-2 hours. Wherein the injection pressure is 0.2-0.6 MPa, the injection time is controlled within 30min, and the filling rate of the bone cement is 80-90%. Due to the mesh design of the supporting wall 21, the injection pressure can be reduced to 0.2-0.6 MPa, and the leakage of bone cement caused by too large injection pressure can be prevented.

Step three: and (3) sintering at low temperature, namely putting the cured honeycomb structure into an atmosphere furnace, setting the temperature rise rate at 5 ℃/min, heating the honeycomb structure to 250-450 ℃, and then preserving the heat for 30-120 min, wherein the vacuum pressure is set to be 0.1MPa, and the sintering atmosphere is nitrogen. The preferred embodiment of the present invention is finally obtained after the sintering.

In the third step, the low-temperature sintering temperature is set to be 250-450 ℃, so that the magnesium or magnesium alloy and bone cement can be sintered, on one hand, the stress relief annealing effect can be realized on the peripheral structure 1 and the framework structure 2 of the magnesium or magnesium alloy material, and the residual internal stress of the magnesium or magnesium alloy is reduced; on the other hand, the hydration reaction of the bone cement is stopped at the temperature of 250-450 ℃, unreacted water and phosphate are removed, and holes are formed, so that the preparation of a porous structure is facilitated, and the generation of blood vessels is facilitated. The mechanical property of magnesium or magnesium alloy is affected by the temperature which is too high and is close to the melting point of magnesium or magnesium alloy. At too low a temperature, the cement needs to be sintered at a higher pressure, which deforms the peripheral structure 1 and the skeleton structure 2 made of magnesium or magnesium alloy.

The body implant with filler of the present invention has the following advantages:

(2) The inner side plate 21 of the present invention is designed in a net shape to facilitate the flow of the filler in the skeleton structure 2, thereby reducing the injection pressure during injection. Meanwhile, the filler 3 forms a continuous state after being cured, on one hand, after the framework structure 2 is degraded, the filler 3 can maintain a whole without being broken, and the stability of the honeycomb structure is ensured; on the other hand, the adhesion between the filler 3 and the skeleton structure 2 is improved, whereby even if the body implant with the filler of the present invention is processed into various shapes, a certain mechanical property can be secured and the filler does not fall off.

The body implant with filler of the present invention can be processed into various shapes in use to make bone-implanted medical devices with various functions, including but not limited to bone plates, implants, spinal fixation implants, artificial joints, etc. The following is a description of specific examples.

The first embodiment is as follows:

in this embodiment, the skeleton structure 2 and the peripheral structure 1 are made of pure magnesium material, and the filler 3 is calcium phosphate cement

In this example, the formulation of the calcium phosphate cement is: the weight ratio of the powder is as follows: 30-40% of tetracalcium phosphate, 30-40% of anhydrous calcium hydrophosphate, 1-5% of boric acid, and liquid: 10% -30% of deionized water; the purity of the tetracalcium phosphate is 99%, and the powder granularity is 30-70 μm; the purity of the anhydrous calcium hydrophosphate is 99 percent, and the granularity is 30-70 mu m; the conductivity of the deionized water is less than 0.5 us/cm; the purity of the boric acid (retarder) is 99%, and the granularity is 30-70 mu m.

Example two:

in the embodiment, the skeleton structure 2 and the peripheral structure 1 are both made of magnesium alloy materials, and the filler 3 is magnesium phosphate cement.

In this embodiment, the formulation of the magnesium phosphate cement is: the magnesium phosphate bone cement comprises the following powder in parts by weight: 33-55% of magnesium oxide, 10-15% of monopotassium phosphate, 5-10% of sodium dihydrogen phosphate, 1-5% of boric acid and the following liquid in percentage by weight: 10 to 20 percent of deionized water; the magnesium oxide is fused magnesium oxide, the purity of the magnesium oxide is 98%, the sintering temperature is 2700 ℃, and the particle size of magnesium oxide powder is 30-70 mu m; the purity of the sodium dihydrogen phosphate is 99 percent, and the granularity is 30-70 mu m; the purity of the sodium dihydrogen phosphate is 99 percent, and the granularity is 30-70 mu m; the conductivity of the deionized water is less than 0.5 us/cm; the purity of the boric acid (retarder) is 99%, and the granularity is 30-70 mu m.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A body implant with filler, comprising:

a peripheral structure;

the framework structure comprises a plurality of supporting walls, and the supporting walls are spliced with each other to form a honeycomb-shaped structure with an upper top surface and a lower bottom surface; the supporting wall is a porous net structure; the supporting walls positioned at the edges of the framework structures are connected with the peripheral structures, and in the space surrounded by the peripheral structures and the framework structures, a filling space with communicated upper top surface and lower bottom surface and closed periphery is formed;

the filler is used for filling the filling space formed after the peripheral structure is connected with the framework structure;

and the injection port is arranged on the peripheral structure or the skeleton structure and is used for injecting the filler into the filling space.

2. The bodily implant of claim 1, wherein the material of both the peripheral structure and the skeletal structure is metallic magnesium or a magnesium alloy.

3. The body implant of claim 1, wherein said support wall has a thickness of 0.3 to 3mm and said porous network of said support wall has a mesh diameter in the range of 0.1 to 0.5 mm.

4. The bodily implant of claim 1 wherein the filler is a porous structure.

5. The bodily implant of claim 1, wherein the filler is a bone cement.

6. The bodily implant of any of claims 1-5, wherein the peripheral structure further comprises an outer support wall and an outer flap; the outer supporting wall is connected with the side face of the framework structure, the outer sealing plates are connected with the upper top face and the lower bottom face of the framework structure, and are connected with the outer supporting wall and seal the framework structure.

7. The body implant of claim 6, wherein said injection ports are reserved at four corners and at a central position of said outer sealing plate.

8. A method for producing a body implant with a filler according to any one of claims 1 to 7, comprising:

processing and connecting the peripheral structure and the framework structure to form a filling space with a honeycomb structure;

injecting a filler, injecting the filler into the filling space through an injection port after the filler is pre-adjusted to a flowable state, and then standing and curing the honeycomb structure into which the filler has been injected;

and (3) low-temperature sintering, namely heating the whole solidified honeycomb structure to 250-450 ℃ for low-temperature sintering to obtain the body implant.

9. The method according to claim 8, wherein in the step of injecting the filler, an injection pressure is set to 0.2 to 0.6MPa, an injection time is controlled within 30 minutes, a filling rate of the filler is controlled to 80 to 99%, and a standing and curing time is 1 to 2 hours.

10. The preparation method according to claim 8, wherein in the step of low-temperature sintering, the holding time is 30-120 min.