3D printing bone repair stent
By designing hard and soft interlaced silk structures in the 3D printed bone repair scaffold, the problem of spatial structure of blood vessels and nerves is solved, synchronous regeneration of blood vessels and nerves is achieved, and the repair of bone defects is promoted.
Patent Information
- Application Number
- CN202422095362.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-28
- Publication Date
- 2025-08-26
- Estimated Expiration
- 2034-08-28
AI Technical Summary
The prior art is difficult to provide both spatial structures suitable for vascular and nerve regeneration in 3D printed bone repair scaffolds, resulting in lag in vascular-neural synchronous regeneration repair strategies.
A 3D printed bone repair scaffold was designed, using a harder, rougher, and larger holes as the first silk thread of endothelial cell growth bed, and a softer, smoother and smaller holes as the nerve regeneration bed. The silk threads are arranged in an interlaced manner and form a complex gap structure, which is suitable for loading different cells or substances and promoting blood vessels and nerve regeneration.
It realizes synchronous regeneration of blood vessels and nerves, provides an appropriate spatial structure foundation, and promotes the repair of bone defects.
Smart Images
Figure CN223263068U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a 3D printed bone repair scaffold, belonging to the field of biological scaffolds. Background Art
[0002] Delayed fracture healing and nonunion often result in bone defects. Bone defects are more common in open fractures, severely impacting limb function. Furthermore, non-traumatic aseptic osteonecrosis is often accompanied by bone defects and joint dysfunction. In recent years, with advances in the diagnosis and treatment of bone tumors, more bone defects after tumor surgery require surgical treatment. Bone defects caused by various causes not only cause significant distress to patients but also consume significant medical resources. Recent research has revealed that bone possesses not only an efficient arteriovenous vascular system but also a rich microvascular system, suggesting that angiogenesis is crucial for bone defect repair. Similar to blood vessels, nerve fibers are also abundant in bone tissues, such as the periosteum, bone marrow, and mineralized bone. These nerve fibers connect to the dorsal root ganglion (DRG) and the central nervous system (CNS), and collaborate with the peripheral nervous system (PNS) to regulate bone tissue development and repair. A growing body of research supports the idea that blood vessels and nerves coexist within bone tissue, playing a synergistic role in bone development and fracture repair. Therefore, the simultaneous regeneration of blood vessels and nerves plays a crucial role in the treatment of bone defects, and targeting both may lead to better therapeutic outcomes.
[0003] Cellular feedback to the extracellular microenvironment underlies a series of subtle changes that follow. Designing specialized three-dimensional structures to create and regulate a suitable regenerative microenvironment is beneficial for promoting tissue repair and regeneration. For example, using 3D printing technology to design a three-dimensional space and then loading it with different growth factors, stem cells, or tissue fragments can induce blood vessel growth within a 3D-printed artificial bone repair scaffold.
[0004] Compared with traditional vascularized or neuralized bone defect repair strategies, research on synchronized vascular and neural regeneration strategies has lagged behind. A key reason for this is that vascular and neural regeneration involve different cell types, stem cell niches, and microenvironments. Providing a suitable structure within a 3D-printed bone repair scaffold to facilitate simultaneous loading of different cells or substances, thereby providing the spatial structural foundation for synchronized vascular and neural regeneration, has become a major challenge in this field. Utility Model Content
[0005] In order to overcome the deficiencies of the prior art, the utility model provides a 3D printed bone repair scaffold.
[0006] The technical solution adopted by the utility model to solve its technical problems is:
[0007] A 3D-printed bone repair scaffold comprises a multilayer forming block parallel to a horizontal plane, adjacent forming blocks do not overlap, the forming block comprises a first wire and a second wire arranged in parallel, the first wire is harder than the second wire, the surface of the first wire is rougher than the surface of the second wire, first holes are distributed on the first wire, second holes are distributed on the second wire, and the aperture of the first hole is larger than the aperture of the second hole.
[0008] In the 3D printed bone repair scaffold provided in the present application, a first silk thread that is harder, rougher, and has larger holes can be used as a bed for endothelial cell growth, and a second silk thread that is softer, smoother, and has smaller holes can be used as a bed for nerve regeneration. The first silk thread and the second silk thread in the same layer of forming blocks are arranged side by side, and the silk threads in adjacent forming blocks are staggered to form an artificial bone base. The gaps between the silk threads are conducive to the regeneration of blood vessels and nerves, and silk threads of different high specifications are conducive to loading different cells or substances.
[0009] Furthermore, a first hollow hole coaxial with the first wire is provided in the first wire.
[0010] Furthermore, a second hollow hole coaxial with the second wire is provided in the second wire.
[0011] Furthermore, the compression modulus of the first wire is greater than 20 KPa, and the compression modulus of the second wire is 0.1 KPa to 1 KPa.
[0012] Furthermore, the surface roughness of the first wire Ra>0.067 μm, and the surface roughness of the second wire Ra<0.01 μm.
[0013] Furthermore, the pore size of the first hole is 140 μm to 200 μm, and the pore size of the second hole is 0.3 μm to 0.8 μm.
[0014] Furthermore, the diameter of the second wire is smaller than that of the first wire.
[0015] Furthermore, on the same layer of the forming blocks, at least one first wire is arranged between adjacent second wires.
[0016] Furthermore, each layer of the forming blocks includes a plurality of parallel wire clusters, and each of the wire clusters includes two first wires and one second wire located between the two first wires.
[0017] Furthermore, the first wires on two adjacent layers of the forming blocks form an angle of 60° or 90°.
[0018] The beneficial effects of the present invention are as follows: in the 3D printed bone repair scaffold of the present invention, the first silk thread, which is harder, rougher and has larger holes, is conducive to better adhesion and growth of endothelial cells, and the second silk thread, which is softer, smoother and has smaller holes, is conducive to nerve regeneration. When the 3D printed bone repair scaffold is used for bone defects, it is beneficial for the second silk thread and the first silk thread to carry different substances, promote the synchronous regeneration of blood vessels and nerves, and provide a spatial structural basis for the synchronous regeneration and repair of blood vessels and nerves.
[0019] Other features and advantages of the present application will be described in the following description, and in part will become apparent from the description, or understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained by the structures particularly pointed out in the written description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 This is a schematic structural diagram of a 3D printed bone repair scaffold provided in an embodiment of the present application.
[0021] Figure 2 yes Figure 1 Enlarged view of point A in the middle.
[0022] Figure 3 This is a side view of a 3D printed bone repair scaffold provided in an embodiment of the present application.
[0023] Reference numerals: 1, first wire; 11, first hollow hole; 12, first hole; 2, second wire; 22, second hollow hole. DETAILED DESCRIPTION
[0024] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.
[0025] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include one or more of the specified features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.
[0026] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.
[0027] The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, the components and configurations of specific examples are described below. Of course, these are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or configurations discussed.
[0028] In situ regulation of cell behavior can be achieved by designing specific nanotopological structures, adjusting material toughness, or bonding special functional groups. This strategy has also been proven to be effective in promoting vascularization and neuralization. [1, 2] , a surface with a certain degree of roughness [3] and larger pore size microenvironments show better adhesion, ductility and capillary density; specifically for neurons, they prefer more flexible three-dimensional structures. [4] Therefore, when designing scaffold materials that can promote the synchronous regeneration of blood vessels and nerves, the construction of appropriate three-dimensional spatial structure, pore size and pore structure cannot be ignored. These parameters will directly affect the penetration of new blood vessel bundles and nerve fibers into the scaffold material.
[0029] Reference Figures 1 to 3 The embodiment of the present application provides a 3D printed bone repair scaffold, comprising a multi-layer forming block parallel to a horizontal plane, wherein adjacent forming blocks do not overlap, and the forming block comprises a first wire 1 and a second wire 2 arranged in parallel, wherein the first wire 1 is harder than the second wire 2, and the surface of the first wire 1 is rougher than the surface of the second wire 2, and the first wire 1 is provided with a first hole 12, and the second wire 2 is provided with a second hole (not numbered in the figure, and its position can be referred to as Figure 2 The first hole 12 has a larger aperture than the second hole 12.
[0030] The first and second threads 1 and 2 are printed using a 3D printer. To meet requirements for softness, hardness, and roughness, the material of the first thread 1 can be, for example, polycaprolactone with a molecular weight of 80,000, and the material of the second thread 2 can be, for example, methacrylated gelatin. The compression modulus of the first thread 1 can be greater than 20 kPa, and the compression modulus of the second thread 2 can be between 0.1 kPa and 1 kPa. The surface roughness Ra of the first thread 1 is greater than 0.067 μm, and the surface roughness Ra of the second thread 2 is less than 0.01 μm. The aperture of the first hole 12 is between 140 μm and 200 μm, and the aperture of the second hole is between 0.3 μm and 0.8 μm. This makes the first thread 1 more suitable for vascular endothelial cell growth, and the second thread 2 more suitable for nerve repair.
[0031] The holes in the filaments can be formed by mixing soluble particles into the 3D printing material to serve as a sacrificial template. After printing, the sacrificial template is washed away in a solvent, leaving the holes. It can be seen that the soluble particles used in the first filament material need to be larger than the soluble particles used in the second filament material. This creates the effect that the diameter of the first hole 12 is larger than that of the second hole.
[0032] Preferably, the first thread 1 is provided with a first hollow hole 11 coaxial with the first thread. Similarly, the second thread 2 is provided with a second hollow hole 22 coaxial with the second thread. The first hollow hole 11 can communicate with part of the first hole 12, and the second hollow hole 22 can communicate with part of the second hole, so that the large gaps and small gaps in the 3D printed bone repair scaffold are interconnected.
[0033] Specifically, a 3D-Bioplotter printer can be used. It can be equipped with a three-channel printhead system. By combining different nozzles, it can achieve controlled distributed printing within a single component, enabling the production of a range of heterogeneous composite porous scaffolds. However, this solution only requires two channels, making this printer fully capable. When used in conjunction with a hollow nozzle, heterogeneous composite porous scaffolds with hollow pore structures can be produced.
[0034] During 3D printing, one layer of building blocks is always printed before the next layer (the "next" layer in terms of process, the "upper" layer in terms of orientation) is printed at a certain angle on the already printed building blocks. Specifically, the first wires 1 on two adjacent layers of building blocks form a 60° or 90° angle, which can create a stable structure.
[0035] Preferably, the diameter of the second wire 2 is smaller than the diameter of the first wire 1. Figure 3 ( Figure 3(Showing four layers of forming blocks), the first threads 1 are thicker, supporting the next layer of forming blocks. This prevents the threads of the next layer from pressing on the softer second threads 2. The first threads 1, as the primary mechanical structure, provide excellent protection for the second threads 2. More preferably, on the same layer of forming blocks, at least one first thread 1 is arranged between adjacent second threads 2. Specifically, each layer of forming blocks includes multiple parallel thread clusters, each of which includes two first threads 1 and a second thread 2 positioned between the two first threads 1, which helps strengthen the protective effect of the first threads 1 on the second threads 2.
[0036] Throughout this specification, references to terms such as "one embodiment," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" indicate that a specific feature, structure, material, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
[0037] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.
[0038] References:
[0039] [1] Yeung T, Georges PC, Flanagan LA, et al. Effects of substratestiffness on cell morphology, cytoskeletal structure, and adhesion. Cellmotility and the cytoskeleton, 2005, 60 (1):24-34.
[0040] [2] Byfield FJ, Reen RK, Shentu TP, et al. Endothelial actin and cell stiffness is modulated by substrate stiffness in 2D and 3D. Journal of biomechanics, 2009, 42 (8):1114-1119.
[0041] [3] Webster TJ, Waid MC, McKenzie JL, et al. Nano-biotechnology:carbon nanofibres as improved neural and orthopaedic implants.Nanotechnology, 2003, 15 (1):48.
[0042] [4] Huebsch N, Arany PR, Mao AS, et al. Harnessing traction-mediatedmanipulation of the cell / matrix interface to control stem-cell fate. Naturematerials, 2010, 9 (6):518-526。
Claims
1. A 3D printed bone repair scaffold, characterized in that: The invention comprises a multi-layer forming block parallel to a horizontal plane, wherein adjacent forming blocks do not overlap, and the forming block comprises a first wire (1) and a second wire (2) arranged in parallel, wherein the first wire (1) is harder than the second wire (2), and the surface of the first wire (1) is rougher than the surface of the second wire (2), and a first hole (12) is distributed on the first wire (1), and a second hole is distributed on the second wire (2), and the aperture of the first hole (12) is larger than the aperture of the second hole.
2. The 3D printed bone repair scaffold according to claim 1, characterized in that: A first hollow hole (11) coaxial with the first wire is provided in the first wire (1).
3. The 3D printed bone repair scaffold according to claim 1, characterized in that: A second hollow hole (22) coaxial with the second wire is provided in the second wire (2).
4. The 3D printed bone repair scaffold according to claim 1, wherein: The compression modulus of the first wire (1) is greater than 20 KPa, and the compression modulus of the second wire (2) is 0.1 KPa to 1 KPa.
5. The 3D printed bone repair scaffold according to claim 1, characterized in that: The surface roughness of the first wire (1) is Ra>0.067 μm, and the surface roughness of the second wire (2) is Ra<0.01 μm.
6. The 3D printed bone repair scaffold according to claim 1, characterized in that: The pore size of the first hole (12) is 140 μm to 200 μm, and the pore size of the second hole is 0.3 μm to 0.8 μm.
7. The 3D printed bone repair scaffold according to claim 1, characterized in that: The diameter of the second wire (2) is smaller than the diameter of the first wire (1).
8. The 3D printed bone repair scaffold according to claim 7, characterized in that: On the same layer of the forming blocks, at least one first wire (1) is arranged between adjacent second wires (2).
9. The 3D printed bone repair scaffold according to claim 8, characterized in that: Each layer of the forming block comprises a plurality of parallel wire clusters, and each of the wire clusters comprises two first wires (1) and one second wire (2) located between the two first wires (1).
10. The 3D printed bone repair scaffold according to claim 1, characterized in that: The first threads (1) on the two adjacent layers of the forming blocks are at an angle of 60° or 90°.