A method for designing and manufacturing an integrated hollow closed obturator using 3D printing

Abstract

The present invention provides a method for designing and manufacturing an integrated hollow closed obturator through 3D printing, which relates to the field of dental technology. The manufacturing method comprises: obtaining a digital model of the patient's dentition and jaw defect area through an intraoral scanner; designing an obturator based on the digital model through a first digital design software to obtain an initial digital model of the obturator; adjusting the position of the initial digital model of the obturator through a second digital design software so that the occlusal plane of the initial digital model of the obturator is parallel to the XY plane, and the tissue surface of the initial digital model of the obturator faces the positive direction of the Z axis. By combining the interlayer pause method with the bottom-up 3D printing method, liquid resin residue in the hollow obturator cavity is avoided, and the direct 3D printing production of the integrated hollow closed obturator can be achieved, providing an effective solution for the direct 3D printing production of hollow structures.

Description

Technical Field

[0001] The present invention relates to the field of dental technology, and in particular to a method for designing and manufacturing an integrated hollow closed obturator through 3D printing. Background Art

[0002] Jaw defects can cause defects in important physiological functions such as speech, chewing, and swallowing, and affect the appearance and aesthetics of the maxillofacial area. Prosthetic restoration is an effective treatment for patients with jaw defects. It often uses a hollow structure to reduce the weight of the prosthesis, thereby achieving good retention and stable repair effects. The traditional method of making hollow prostheses is complicated, time-consuming, and has low precision. It is difficult to ensure that the thickness of the resin wall in the hollow part is uniform. At the same time, it needs to be divided into two parts, an open base and a palate cover, and the two parts are bonded by self-curing resin, or different materials are used as a medium to maintain the hollowness. After opening a hole to remove the internal medium, the part is bonded to obtain the final closed hollow obstructer. In this process, poor sealing is likely to occur, causing liquid infiltration and increasing the weight of the prosthesis. At the same time, the bonding seams are also prone to bacterial adhesion and reproduction, affecting the aesthetics of the prosthesis and the health of the patient.

[0003] Although computer-aided design and computer-aided manufacturing (CAD / CAM) have been gradually applied to the field of maxillofacial prosthetic treatment, especially 3D printing technology for producing objects with complex structures, it can be used to produce hollow obturators. However, the current mainstream 3D printing technology requires sufficient resin in the printing tank to ensure that the liquid resin can smoothly flow back and replenish after the printing platform is lifted for the next curing process. However, this process is likely to cause liquid resin to accumulate inside the cavity when printing the one-piece hollow closed obturator, making it impossible to complete the production of the hollow model. Currently, most hollow obturators produced by 3D printing technology still need to print two parts and then bond them together, which fails to avoid the problems existing in the production of traditional hollow structures. Summary of the Invention

[0004] The present invention provides a method for designing and manufacturing an integrated hollow closed obturator by 3D printing, so as to solve the problem in the prior art that liquid resin is retained in the cavity when the hollow closed obturator is printed and manufactured.

[0005] The present invention provides a method for designing and manufacturing an integrated hollow closed obturator by 3D printing, comprising:

[0006] Obtain a digital model of the patient's dentition and jaw defect area using an intraoral scanner;

[0007] Designing an occluder based on the digital model using a first digital design software to obtain an initial occluder digital model;

[0008] Adjusting the position of the initial digital model of the occluder using a second digital design software so that the occlusal plane of the initial digital model of the occluder is parallel to the XY plane and the tissue surface of the initial digital model of the occluder faces the positive direction of the Z axis; copying the initial digital model of the occluder and offsetting the copied initial digital model inward by a predetermined distance to obtain a digital model of the inner surface of the hollow occluder;

[0009] Using an XY plane, a cutting operation is performed on the top of the tissue surface of the digital model of the inner surface of the hollow obturator and the intersecting surface is closed to obtain a first plane;

[0010] Generating a second plane parallel to the first plane at the bottom of the polished surface of the initial digital model of the obstructer; extending the second plane along the positive direction of the Z axis to a predetermined depth from the boundary and closing the bottom to obtain a printing direction indicator block; performing an additive Boolean operation on the printing direction indicator block and the initial digital model of the obstructer to obtain a digital model of the outer surface of the hollow obstructer; flipping the normal direction of the digital model of the inner surface of the hollow obstructer and combining it with the digital model of the outer surface of the hollow obstructer to generate a hollow obstructer model;

[0011] Slicing the hollow obturator model using slicing software;

[0012] A hollow obturator is manufactured according to the hollow obturator model after slicing.

[0013] According to a method for designing and manufacturing an integrated hollow closed obturator by 3D printing provided by the present invention, the step of slicing the hollow obturator model using slicing software includes:

[0014] Importing the hollow obturator model into the slicing software and adding support with the second plane as the bottom surface;

[0015] removing the support of the hollow structure inside the hollow obturator model;

[0016] Get the printing parameters and record the slice layer number where the first plane is located.

[0017] According to a method for designing and manufacturing an integrated hollow closed obturator through 3D printing provided by the present invention, the step of manufacturing the hollow obturator according to the hollow obturator model after slicing includes:

[0018] Printing the sliced ​​hollow obturator model through a 3D printer;

[0019] When the recorded number of layers is printed, the printing platform of the 3D printer is controlled to return to the highest position. After pausing printing for a predetermined time, the printing platform is controlled to descend into the liquid resin to continue printing. The above steps are repeated until the entire model is printed.

[0020] According to the method for designing and manufacturing an integrated hollow closed obturator by 3D printing provided by the present invention, after the step of manufacturing the hollow obturator according to the hollow obturator model after slicing, the method further includes:

[0021] performing post-processing on the hollow obturator;

[0022] A metal wire is bent into a clamping ring and fixed to the hollow obturator with resin.

[0023] According to a method for designing and manufacturing an integrated hollow closed obturator by 3D printing provided by the present invention, the predetermined distance is 1.5 mm to 2.5 mm.

[0024] According to a method for designing and manufacturing an integrated hollow closed blocker by 3D printing provided by the present invention, the first plane is the closed first layer of the hollow structure, and the area of ​​the first plane is less than 30 mm2.

[0025] According to a method for designing and manufacturing an integrated hollow closed blocker by 3D printing provided by the present invention, the second plane is a printing direction indicating plane or a support attachment plane.

[0026] According to a method for designing and manufacturing an integrated hollow closed occluder by 3D printing provided by the present invention, the first digital design software is Exocad DentalCAD ​​software or 3Shape Dental System software.

[0027] According to a method for designing and manufacturing an integrated hollow closed obturator by 3D printing provided by the present invention, the second digital design software is Geomagic Wrap software.

[0028] According to a method for designing and manufacturing an integrated hollow closed obturator by 3D printing provided by the present invention, the thickness of the slice printing layer in the 3D printing process is 50μm-100μm.

[0029] The method for designing and manufacturing an integrated hollow closed obturator by 3D printing provided by the present invention has the following advantages:

[0030] 1. By combining the interlayer pause method with the bottom-up 3D printing method, liquid resin residue in the hollow blocker cavity is avoided, and the direct 3D printing production of the integrated hollow closed blocker can be achieved, providing an effective solution for the direct 3D printing production of hollow structures.

[0031] 2. The hollow blocker made by the interlayer suspension method avoids the current mainstream method of achieving hollow sealing by bonding, which can reduce the problems caused by hollow bonding and ensure the sealing and stability of the blocker while reducing the weight of the blocker.

[0032] 3. The interlayer pause hollow printing technology can reduce the difficulty of manufacturing traditional hollow obturators, improve the production efficiency and quality of obturators, make the production process more convenient and feasible, and facilitate repeated production. At the same time, its production accuracy meets the needs of clinical applications and is easy to promote and apply on a larger scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 It is a flow chart of the method for designing and manufacturing an integrated hollow closed obturator by 3D printing provided by the present invention.

[0035] Figure 2 It is a schematic diagram of the digital model provided by the present invention.

[0036] Figure 3 Schematic diagram of the initial occluder digital model provided by the present invention.

[0037] Figure 4 It is a schematic diagram of a digital model of the inner surface of the hollow obturator after the shell is extracted provided by the present invention.

[0038] Figure 5 It is a schematic diagram of the digital model of the inner surface of the hollow obturator provided by the present invention.

[0039] Figure 6 It is a schematic diagram of the digital model of the outer surface of the hollow obturator provided by the present invention.

[0040] Figure 7 Schematic diagram of the hollow obturator model provided by the present invention.

[0041] Figure 8 Schematic diagram of the hollow obturator provided by the present invention.

[0042] Reference numerals:

[0043] 10. Digital model; 20. Initial occluder digital model; 30. Digital model of the inner surface of the hollow occluder; 40. Digital model of the outer surface of the hollow occluder; 60. Hollow occluder model; 70. Hollow occluder. DETAILED DESCRIPTION

[0044] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0045] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0046] In the description of the embodiments of the present invention, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; and direct connections or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of the present invention based on the specific circumstances.

[0047] In the embodiments of the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," or "above" a second feature may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. A first feature being "below," "below," or "below" a second feature may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0048] The following combination Figures 1-8The present invention describes a method for designing and manufacturing an integrated hollow closed occluder using 3D printing.

[0049] like Figure 1 As shown, the method for designing and manufacturing an integrated hollow closed occluder by 3D printing includes steps S100 to S800.

[0050] Step S100 : obtaining a digital model 10 of the patient's dentition and jaw defect area through an intraoral scanner.

[0051] Step S200 , designing an occluder based on the digital model 10 using a first digital design software to obtain an initial occluder digital model 20 .

[0052] It should be noted here that the first digital design software is Exocad DentalCAD ​​software or 3ShapeDental System software.

[0053] Step S300: Adjust the position of the initial occluder digital model 20 through the second digital design software so that the occlusal plane of the initial occluder digital model 20 is parallel to the XY plane, and the tissue surface of the initial occluder digital model 20 faces the positive direction of the Z axis; copy the initial occluder digital model 20, and offset the copied initial occluder digital model 20 inward by a predetermined distance to obtain a digital model 30 of the inner surface of the hollow occluder.

[0054] The purpose of offsetting the copied initial occluder digital model 20 inward by a predetermined distance is to make the hollow occluder inner surface digital model 30 have a certain thickness, the thickness of which is specifically determined by the predetermined distance, which is 1.5 mm to 2.5 mm, preferably 2 mm.

[0055] It should be noted here that the second digital design software is Geomagic Wrap software.

[0056] Step S400 : Using the XY plane, a cutting operation is performed on the top of the tissue surface of the digital model 30 of the inner surface of the hollow obturator and the intersecting surface is closed to obtain a first plane.

[0057] It should be noted that the first plane is a closed first floor of a hollow structure, and the area of ​​the first plane is less than 30mm 2 After obtaining the first plane, the design of the digital model 30 of the inner surface of the hollow obturator is completed, and then the design of the digital model 40 of the outer surface of the hollow obturator is carried out. Setting a closed first layer can facilitate the outflow of liquid after pausing printing and has little effect on the curing of the lower layer.

[0058] Step S500, generate a second plane parallel to the first plane at the bottom of the polished surface of the initial blocker digital model 20; extend the second plane along the positive direction of the Z axis to a predetermined depth from the boundary and close the bottom to obtain a printing direction indication block; perform an additive Boolean operation on the printing direction indication block and the initial blocker digital model 20 to obtain a digital model 40 of the outer surface of the hollow blocker.

[0059] It should be noted that the second plane is the printing direction indicating plane or the support attachment plane. The second plane is extended along the positive Z-axis to a predetermined depth from the boundary to ensure that it can penetrate the initial blocker digital model 20. Setting the second plane facilitates determining the location of subsequent support additions.

[0060] It should also be noted that the XY plane and the positive direction of the Z axis in the present invention are both three-dimensional coordinate systems provided in the software.

[0061] In step S600 , the digital model 30 of the inner surface of the hollow occluder is flipped in a normal direction and combined with the digital model 40 of the outer surface of the hollow occluder to generate a hollow occluder model 60 .

[0062] Step S700 , slicing the hollow obturator model 60 using slicing software.

[0063] Step S800 : manufacturing a hollow occluder 70 according to the hollow occluder model 60 after slicing.

[0064] It should be noted here that the slice printing layer thickness in the 3D printing process is 50μm-100μm, which is determined according to the characteristics of different printers and actual application requirements.

[0065] The method for designing and manufacturing an integrated hollow closed obturator by 3D printing provided by the present invention has the following advantages:

[0066] 1. By combining the interlayer pause method with the bottom-up 3D printing method, liquid resin residue in the hollow blocker cavity is avoided, and the direct 3D printing production of the integrated hollow closed blocker can be achieved, providing an effective solution for the direct 3D printing production of hollow structures.

[0067] 2. The hollow blocker 70 produced by the interlayer pause printing method avoids the current mainstream method of achieving hollow sealing by bonding, can reduce the problems caused by hollow bonding, and ensure the sealing and stability of the blocker while reducing the weight of the blocker.

[0068] 3. The interlayer pause hollow printing method can reduce the difficulty of manufacturing the traditional hollow obturator 70, improve the manufacturing efficiency and quality of the obturator, make the manufacturing process more convenient and feasible, and facilitate repeated manufacturing. At the same time, its manufacturing accuracy can meet the needs of clinical applications and is easy to promote and apply on a larger scale.

[0069] In a specific embodiment of the present invention, the step of slicing the hollow obturator model 60 by using slicing software includes steps S710 to S730.

[0070] Step S710 , importing the hollow obturator model 60 into the slicing software and adding support using the second plane as the bottom surface;

[0071] It should be noted here that the direction of adding support is towards the positive direction of the Z axis.

[0072] Step S720, removing the support of the hollow structure inside the hollow blocker model 60;

[0073] Step S730 , obtaining printing parameters and recording the slice layer number where the first plane is located.

[0074] In a specific embodiment of the present invention, the step of making the hollow occluder 70 according to the sliced ​​hollow occluder model 60 includes steps S810 to S820.

[0075] Step S810: Print the sliced ​​hollow obturator model 60 using a 3D printer.

[0076] Step S820: When the recorded number of layers is printed, the printing platform of the 3D printer is controlled to return to the highest position. After pausing printing for a predetermined time, the printing platform is controlled to descend into the liquid resin to continue printing. The above steps are repeated until the entire model is printed.

[0077] In this embodiment, the predetermined time is 60 seconds. Of course, the predetermined time is not limited thereto and is determined according to actual needs. The printing platform of the 3D printer is controlled to return to the highest position and printing is paused for a predetermined time to fully flow out the liquid resin remaining in the hollow cavity.

[0078] The processing and manufacturing method of the hollow blocker 70 of the present invention adopts a 3D printing device that can print from the bottom up; different types of printing devices such as stereolithography (SLA), digital light processing (DLP) and liquid crystal display (LCD) can be used. During the printing process, the bottom layer of the model is immersed in the resin liquid, and the lifting height of the printing device needs to meet the requirement that the bottom layer of the model is completely away from the resin liquid surface. The slicing software provided by the 3D printing device can be used to design the printing parameters; different printing devices can edit and delete the hollow internal support according to their characteristics or choose not to generate internal support when setting the support; check the blocker with the hollow internal support structure removed, and observe whether there are isolated points in each layer of the slice. For the blocker model with isolated points, it is necessary to pre-process the position of the model or add individual supports to ensure the printing effect.

[0079] In a specific embodiment of the present invention, after the step of manufacturing the hollow obturator 70 according to the sliced ​​hollow obturator model 60, the method of designing and manufacturing an integrated hollow closed obturator by 3D printing further includes steps S910 to S920.

[0080] Step S910, post-processing the hollow obturator 70;

[0081] In step S920 , the metal wire is bent into a clamping ring and fixed on the hollow obturator 70 with resin.

[0082] The following combination Figures 2 to 8 Describe a specific embodiment of the present invention, such as Figures 2 to 8 As shown, the method for designing and manufacturing an integrated hollow closed blocker by 3D printing further includes steps S100 to S900.

[0083] Step S100: Obtain a digital model 10 of the patient's dentition and jaw defect area through an intraoral scanner. The digital model 10 is exported in STL format. Figure 2 shown.

[0084] Step S200: import the digital model 10 into the dental design software Exocad, design the occluder based on the digital model 10, and export the obtained initial occluder digital model 20 in STL format. Figure 3 shown.

[0085] Step S300: Import the initial occluder digital model 20 into the reverse engineering software Geomagic Wrap, adjust the position of the initial occluder digital model 20 so that the occlusal plane of the initial occluder digital model 20 is parallel to the XY plane, and make the tissue surface of the initial occluder digital model 20 face the positive direction of the Z axis; copy the initial occluder digital model 20, and offset the copied initial occluder digital model 20 inward by a predetermined distance to obtain a digital model 30 of the inner surface of the hollow occluder, as shown in FIG. Figure 4 shown.

[0086] Step S400, using the XY plane to perform a cutting operation on the top of the tissue surface of the digital model 30 of the inner surface of the hollow obturator and close the intersecting surface to obtain a first plane, such as Figure 5 shown.

[0087] Step S500: Generate a second plane parallel to the first plane at the bottom of the polished surface of the initial digital model 20 of the obturator, with a length and width of 8 mm and 4 mm respectively; extend the second plane out of the boundary by a predetermined depth along the positive direction of the Z axis and close the bottom to obtain a printing direction indicator block; perform an addition Boolean operation on the printing direction indicator block and the initial digital model 20 of the obturator to obtain a digital model 40 of the outer surface of the hollow obturator, as shown in FIG. Figure 6 shown.

[0088] Step S600: flip the inner surface digital model 30 of the hollow obstructer to its normal direction and combine it with the outer surface digital model 40 of the hollow obstructer to generate a hollow obstructer model 60. Figure 7 shown.

[0089] In step S700, the hollow blocker model 60 is imported into the slicing software (PreForm). Internal support is not generated, and support is added with the second plane as the bottom surface. The layer thickness is set to 50 μm in the slicing software, and the model is sliced ​​into 1031 layers in total. The last layer before the hollow structure begins to be closed corresponds to the 971th layer.

[0090] In step S800, the sliced ​​hollow obstructer model 60 is printed using an SLA printer (Form3B+) and a base material (Denture Base RP Resin). When printing reaches the 971th recorded slice layer, the printing platform of the 3D printer is controlled to return to the highest position. After pausing printing for 60 seconds, the printing platform is controlled to descend into the liquid resin to continue printing. The above steps are repeated until the entire model is printed.

[0091] Step S900: Remove the support from the processed hollow obturator 70 and place it in a Form Wash machine and clean it with 90% isopropyl alcohol for 10 minutes to remove excess resin on the surface. After drying, immerse it in a glass container filled with glycerin and place it in a post-curing box for 60 minutes to completely cure the remaining liquid resin in the cavity. Bend the metal wire (diameter 0.9mm) of the hollow obturator 70 into a clamping ring and fix it to the hollow obturator with resin. Figure 8 shown.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for designing and manufacturing an integrated hollow closed obturator by 3D printing, characterized in that: include: Obtain a digital model of the patient's dentition and jaw defect area using an intraoral scanner; Designing an occluder based on the digital model using a first digital design software to obtain an initial occluder digital model; Adjusting the position of the initial digital model of the occluder using a second digital design software so that the occlusal plane of the initial digital model of the occluder is parallel to the XY plane and the tissue surface of the initial digital model of the occluder faces the positive direction of the Z axis; copying the initial digital model of the occluder and offsetting the copied initial digital model inward by a predetermined distance to obtain a digital model of the inner surface of the hollow occluder; Using an XY plane, a cutting operation is performed on the top of the tissue surface of the digital model of the inner surface of the hollow obturator and the intersecting surface is closed to obtain a first plane; Generating a second plane parallel to the first plane at the bottom of the polished surface of the initial digital model of the obturator; extending the second plane out of the boundary by a predetermined depth along the positive direction of the Z axis and closing the bottom to obtain a printing direction indicator block; performing an additive Boolean operation on the printing direction indicator block and the initial digital model of the obturator to obtain a digital model of the outer surface of the hollow obturator; Flipping the digital model of the inner surface of the hollow obstructer in a normal direction and combining it with the digital model of the outer surface of the hollow obstructer to generate a hollow obstructer model; Slicing the hollow obturator model using slicing software; making a hollow obturator according to the hollow obturator model after slicing; The step of making a hollow obturator according to the hollow obturator model after slicing comprises: Printing the sliced ​​hollow obturator model through a 3D printer; When the recorded number of layers is printed, the printing platform of the 3D printer is controlled to return to the highest position. After pausing printing for a predetermined time, the printing platform is controlled to descend into the liquid resin to continue printing. The above steps are repeated until the entire model is printed.

2. The method for designing and manufacturing an integrated hollow closed obturator by 3D printing according to claim 1, characterized in that: The step of slicing the hollow obturator model using slicing software includes: Importing the hollow obturator model into the slicing software and adding support with the second plane as the bottom surface; removing the support of the hollow structure inside the hollow obturator model; Get the printing parameters and record the slice layer number where the first plane is located.

3. The method for designing and manufacturing an integrated hollow closed obturator by 3D printing according to claim 2, characterized in that: After the step of making a hollow obturator according to the hollow obturator model after slicing, the method further includes: performing post-processing on the hollow obturator; A metal wire is bent into a clamping ring and fixed to the hollow obturator with resin.

4. The method for designing and manufacturing an integrated hollow closed obturator by 3D printing according to any one of claims 1 to 3, characterized in that: The predetermined distance is 1.5 mm to 2.5 mm.

5. The method for designing and manufacturing an integrated hollow closed obturator by 3D printing according to any one of claims 1 to 3, characterized in that: The first plane is the closed first floor of the hollow structure, and the area of ​​the first plane is less than 30 mm 2 .

6. The method for designing and manufacturing an integrated hollow closed obturator by 3D printing according to any one of claims 1 to 3, characterized in that: The second plane is a printing direction indicating plane or a support attachment plane.

7. The method for designing and manufacturing an integrated hollow closed obturator by 3D printing according to any one of claims 1 to 3, characterized in that: The first digital design software is Exocad DentalCAD ​​software or 3Shape DentalSystem software.

8. The method for designing and manufacturing an integrated hollow closed obturator by 3D printing according to any one of claims 1 to 3, characterized in that: The second digital design software is Geomagic Wrap software.

9. The method for designing and manufacturing an integrated hollow closed obturator by 3D printing according to claim 2 or 3, characterized in that: The slice printing layer thickness in the 3D printing process is 50 μm-100 μm.

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