KR20170038444A

KR20170038444A - Manufacturing method of bone fixation device, bone fixation device manufactured by the same, filament for 3D printer and manufacturing method of the same

Info

Publication number: KR20170038444A
Application number: KR1020150137824A
Authority: KR
Inventors: 박찬흠; 이민채; 이옥주; 주형우; 문보미; 이정민; 박현정; 박예리; 김동욱; 김수현; 정주연
Original assignee: 한림대학교 산학협력단
Priority date: 2015-09-30
Filing date: 2015-09-30
Publication date: 2017-04-07

Abstract

The present invention relates to a method and apparatus for performing 3D imaging of a bone fixation device corresponding to a fracture site based on the image data by acquiring tomographic image data by photographing a fracture site of a patient with a medical tomography imaging device, A modeling step, a raw material supplying step of supplying a filament including polylactic acid (PLA) and hydroxyapatite (HA) to a 3D printer, and a step of supplying a bone fixing device to the 3D printer through the 3D printer using the 3D data. The present invention relates to a method of manufacturing a bone fixation device including a step of producing a bone fixation device for printing, a bone fixation device manufactured by the method, and a filament for a 3D printer used for manufacturing the bone fixation device, and a method of manufacturing the same. According to the present invention, it is possible to provide a patient-customized bone fixation device capable of performing bone joint surgery without a surgical procedure for forming a hole in a bone using 3D printing technology, and a biocompatible material such as polylactic acid and hydroxyapatite The bone regeneration can be promoted and the damaged fracture site can be treated more quickly and stably.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of manufacturing a bone fixation device, a bone fixation device manufactured by the method, a filament for a 3D printer used for manufacturing the bone fixation device, and a method of manufacturing the same. , filament for 3D printer and manufacturing method of the same}

The present invention relates to a method of manufacturing a bone fixation device, a bone fixation device manufactured by the method, and a filament for a 3D printer used for manufacturing the bone fixation device and a method of manufacturing the same.

The 3D printing technology is based on three-dimensional design data, and can be applied to a physical model, a prototype type, and a physical model by using a lamination method (lamination method) in which a material such as a polymer substance, a plastic or a metallic powder is layered one by one, It is a technology to shape tools and parts.

The advantage of 3D printing is that even if only one product is produced, the production cost is relatively low, and any shape product can be freely produced. In the conventional model manufacturing technology, since a mold is manufactured and a product is manufactured using a mold, the cost of manufacturing a single product is very high. However, in the 3D printing technology, Therefore, it is very suitable for small quantity production of various kinds. In addition, according to 3D printing technology, it is possible to produce any complex shape product easily, so the kind of products that can be produced using 3D printing technology is virtually unlimited. As a result, 3D printing technology is expected to lead the industry innovation by changing the technology paradigm in various fields such as manufacturing, medical and IT.

In recent years, 3D printing technology has been used in various medical fields and is more efficient in terms of production time, cost, and process than existing cutting processing. Particularly in orthopedics, attention is focused on 3D printing technology as an improvement of operation time, operation accuracy, reduction of patient suffering and minimization of reoperation.

For example, conventionally, as a surgical method for joining a fractured bone, a treatment method for fixing and healing a fractured bone using a bone plate and a screw has been widely used. Specifically, after the fractured bone is aligned, a plate for bone joining made of a titanium or stainless steel-based metal material excellent in biostability and compatibility is placed, and bone fractured through a plurality of holes formed in the bone- It is a method of operation in which a hole is formed using a drill, and then a screw is used to fix the fractured bone. In this case, in order to improve the success rate and accuracy of the operation, it is very important to select a plate suitable for the position and shape of the fracture site.

As a method for solving such a problem, Patent Document 1 (Korean Patent Laid-open Publication No. 10-2013-0045005) discloses a bone bridge plate which is freely deformed by fitting a fracture bone site, position, Discloses a multifunctional bone bonding plate that can be used.

However, even with the above-described method, it is difficult to manufacture a plate precisely fitted to a fracture site. In addition, since a surgical procedure that forms a hole in the bone is necessary for screw connection during bone graft surgery, it takes a long time for operation, which may impose a burden on the patient's condition, and the healing time is also long.

Therefore, by developing a bone fixation device that can be attached to the fracture site of a patient without the need for a surgical procedure to form a hole in the bone using 3D printing technology, it is possible to shorten the operation time and the healing time, Research is needed.

KR 1020130045005 A

The present invention provides a method of manufacturing a customized bone fixation device for a fractured part of a patient using a 3D printing method and a bone fixation device manufactured by the method.

The present invention is to provide a filament for a 3D printer comprising polylactic acid and hydroxyapatite which can be used in the bone fixation device, and a method for producing the filament.

According to an aspect of the present invention, there is provided a method of manufacturing a bone fixation device using a 3D printing method, including: a tomographic imaging step of acquiring tomographic image data by photographing a fractured portion of a patient with a medical tomographic imaging device; A 3D modeling step of generating 3D data of a bone anchoring device corresponding to the fracture site based on the image data, a 3D modeling step of forming a filament including polylactic acid (PLA) and hydroxyapatite (HAp) And a bone fixation device generating step of 3D printing the bone fixation device through the 3D printer using the 3D data.

The medical tomographic imaging apparatus includes a computer tomography (CT) apparatus, a magnetic resonance imaging (MRI) apparatus, a positron emission tomography (PET) apparatus, and a single photon emission computed tomography (SPECT) device).

The content of HAp in the filament may be 1 to 15 parts by weight based on 100 parts by weight of the PLA, and the diameter of the filament may be 1.0 to 2.0 mm.

The nozzle diameter of the 3D printer may be 0.2 to 0.4 mm.

The present invention also provides a bone fixation device manufactured by the above manufacturing method, and provides a filament for a 3D printer and a method of manufacturing the same, which are used in the method of manufacturing the bone fixation device.

The method for manufacturing a filament for a 3D printer according to the present invention includes a mixing step of mixing HAp with PLA and an extruding step of extruding the PLA and HAp into a filament form.

The PLA may be in the form of a pellet. In this case, the PLA may further include a primary pulverizing step of pulverizing the PLA before the mixing step. In this case, the average size of pulverized PLA is preferably 5 to 50 mu m.

In the mixing step, the HAp may be in powder form, and in the mixing step, the HAp may be mixed in an amount of 1 to 15 parts by weight based on 100 parts by weight of the PLA.

And a second pulverizing step of pulverizing the PLA and the HAp after the mixing step.

The extrusion temperature in the extrusion step may be 170 to 215 캜.

According to the present invention, it is possible to provide a patient-customized bone fixation device capable of performing bone joint surgery without a surgical procedure for forming a hole in a bone using 3D printing technology. Therefore, it is possible to shorten the operation time and the healing time and improve the accuracy of the operation, thereby alleviating the suffering of the patient and minimizing the reoperation due to the operation error.

According to the present invention, by using a biocompatible material such as polylactic acid and hydroxyapatite as a material of a filament for a 3D printer used for manufacturing the above-mentioned bone anchoring device, bone regeneration is promoted and the damaged fracture site is more quickly and stably Can be treated.

1 is a cross-sectional photograph (A) and a longitudinal section photograph (B) of a filament for a 3D printer manufactured according to an embodiment.
2 shows a clip model of a bone anchoring device manufactured according to an embodiment.
FIG. 3 shows a bone fixation device manufactured according to an embodiment.
FIG. 4 is a cross-sectional scanning electron microscope (SEM) image and energy dispersive X-ray spectroscopy (EDS) analysis of the bone fixation device manufactured according to the embodiment ).
Fig. 5 shows a cross-sectional SEM photograph (image) and an EDS analysis result (bottom) of the bone anchor manufactured according to the comparative example.
FIG. 6 is a graph showing the correlation between the compressive strength and the strain of the bone anchoring device manufactured according to the example and the comparative example.
FIG. 7 is a graph showing MTT analysis results of the filaments prepared according to Examples and Comparative Examples by day.
8 is a photograph showing a procedure of implanting a bone fixation device into a laboratory rat.
FIG. 9 is a photograph of the bone anchoring device implanted in the experimental rat of FIG. 8 taken at different angles.
FIG. 10 is a photograph of the bone anchoring device implanted in the experimental rat of FIG. 8 taken at another angle.
In FIG. 11, A is a CT image of a femur of a mouse that has been implanted for 8 weeks after insertion of a bone anchoring device, and B, C, and D are images obtained by changing the CT image to a VR image by changing the size and angle .

First, a method of manufacturing a bone fixation device includes a tomographic imaging step of acquiring tomographic image data by photographing a fracture site of a patient with a medical tomographic imaging device, A 3D modeling step of generating 3D data for a corresponding bone fixation device, a raw material supplying step of supplying a filament containing polylactic acid (PLA) and hydroxyapatite (HAp) to a 3D printer, And a bone fixation device for 3D printing the bone fixation device through the 3D printer using the bone fixation device.

Below. A method of manufacturing a bone anchor according to an embodiment of the present invention will be described in detail.

(1) Tomographic imaging step

This step is to acquire tomographic image data by photographing a fracture site of a patient with a medical tomographic imaging apparatus. At this time, the medical tomographic imaging apparatus used may be a computer tomography (CT) apparatus, a magnetic resonance imaging (MRI) apparatus, a positron emission tomography (PET) apparatus and a single photon- a single photon emission computed tomography (SPECT) apparatus, and preferably a CT apparatus.

The image data obtained from the tomographic imaging apparatus may be a plurality of tomographic image data obtained by photographing a fracture site of a patient at regular intervals. For example, the image data may be digital image and communication in Medicine (DICOM) Data format.

(2) 3D modeling step

This step is a step of generating 3D data for the bone anchoring device corresponding to the fracture site of the patient based on the tomographic image data obtained in the step (1).

For example, the 3D modeling step may include (i) representing the tomographic images obtained from the step (1) by a volume rendering (VR) image, (ii) displaying the VR image on a shaded surface display SSD) image and then storing it as a stereolithography (STL) file, (iii) dividing the STL file into a size that can be output at one time, and then converting the G- and generating a code. Then, the 3D printers output the bone fixation device using the G-code thus generated.

Here, the STL file is a 3D printer standard file format, which is a file storing the position data of each corner point by dividing the surface of the 3D model into a large number of sets of triangles. In order to output the model in the 3D printer, the start and end of printing are controlled, and the direction and order of movement of the nozzle, the speed, the stack height, the thickness of the wall, the temperature of the nozzle and the heat bed, It is called G-code that all the relevant information is included, and the layer is divided in accordance with the stacking height.

(3) Feeding step

This step is a step of supplying the 3D printer with a filament containing polylactic acid (PLA) and hydroxyapatite (HAp), which is used as the material of the bone fixation device.

The bone anchoring device is a biomedical medical device which is inserted into a living body and exhibits a desired function, and must have mechanical strength capable of withstanding repeated loads and momentary pressures, as well as being biocompatible. . Accordingly, in the present invention, filaments including PLA and HAp capable of satisfying these conditions are manufactured and supplied to a 3D printer, and then outputted to a 3D printer to produce a bone fixation device. Herein, " biocompatibility " refers to tissue compatibility and blood compatibility that do not cause necrosis of tissue or coagulation of blood by contact with living tissue or blood, and PLA is a non-toxic polymer capable of decomposing in the body, as a kind of biocompatible polymer , And HAp is a ceramic having the same composition as that of human bone and having excellent biocompatibility and bioaffinity.

The content of HAp in the filament is preferably 1 to 15 parts by weight based on 100 parts by weight of the PLA. If the content of HAp is less than 1 part by weight, the cell affinity of the bone fixation device manufactured from the filament may be lowered. On the other hand, when the content of HAp is more than 15 parts by weight, the tensile strength may be lowered during filament production, resulting in frequent occurrence of nozzle clogging when outputting to a 3D printer, and the compressive strength of the bone- .

The filaments may have a diameter of 1.0 to 2.0 mm, preferably 1.7 to 1.8 mm in diameter. If the diameter of the filament is less than 1.0 mm, it is difficult to manufacture the printing head for pushing the filament, and the printing speed may be too late. If the filament is more than 2.0 mm, the solidification speed is slow and the printing line becomes thick.

(4) Bone fixation device creation step

This step is 3D printing of the bone anchoring device through the 3D printer using the 3D data obtained from the step (2).

In the present invention, as the 3D printing method, a fused deposition modeling (FDM) method is used in which a filament, which is a thermoplastic material, is melted by heat and then extruded through a nozzle to form a laminate.

The diameter of the nozzle is an element capable of determining the accuracy of a three-dimensional object, and may preferably be 0.2 to 0.4 mm. If the diameter of the nozzle is less than 0.2 mm, the output speed may be lowered and the productivity may be deteriorated. On the other hand, if the diameter is larger than 0.4 mm, the accuracy of the bone fixation device may decrease. However, since the viscosity of the raw material in the nozzle may vary depending on the blending ratio of PLA and HAp and the heating temperature, the diameter of the nozzle is not limited to the above range, and can be appropriately modified.

As described above, when the 3D printing method is used for manufacturing the bone anchoring device, it is more efficient in terms of manufacturing time, cost, and process than the conventional cutting method.

The present invention provides a bone anchoring device according to the above manufacturing method. The bone fixation device is a customized medical device fitted to the fracture site of individual patients. It can improve the operation time, operation accuracy and the like during the fracture operation, alleviate the pain of the patient, give.

The present invention also provides a filament for a 3D printer and a method of manufacturing the same, which are used in the above-described method for manufacturing a bone anchoring device.

The filament for a 3D printer includes PLA and HAp which are biocompatible materials as described in (3) raw material supplying step, and the content of HAp is preferably 1 to 15 parts by weight based on 100 parts by weight of PLA, The diameter of the filament may be 1.0 to 2.0 mm.

Such a method for producing a filament for a 3D printer includes a mixing step of mixing HAp into PLA and an extrusion step of extruding the PLA and HAp to produce filament.

The PLA may be in the form of a powder or pellet, preferably in the form of a pellet. When the PLA is in the form of a pellet, it may further comprise a primary pulverizing step of pulverizing the PLA of the pellet before the mixing step. In this case, the average size of pulverized PLA may be 5 to 50 탆. When PLA has an average size in the above range, HAp and PLA are uniformly mixed in the mixing step, and HAp is uniformly dispersed in PLA Can be obtained.

The HAp may be in the form of a powder, a granule, a thin film, a porous body, a dense body, a rod or a plate, preferably in the form of a powder.

In the mixing step, the HAp may be mixed in an amount of 1 to 15 parts by weight based on 100 parts by weight of the PLA. When HAp is included in the range, the biocompatibility and tensile strength are advantageous.

After the mixing step, the PLA and the HAp may be further subjected to a second grinding step. As a result, the size of the PLA and the HAp particles is reduced to a minimum, so that the air gap between the PLA and the HAp particles is extruded while filling the filaments, thereby minimizing the formation of pores in the filaments . 4 is a cross-sectional SEM photograph of a bone anchoring device manufactured using a filament including PLA and HAp, and FIG. 5 is a cross-sectional SEM photograph of a bone anchoring device manufactured using a PLA filament. 4 and FIG. 5, it can be seen that the cavity structure is not completely filled in the bone fixation device shown in FIG. 4, but the cavity is observed. This indicates that the filaments are extruded with the pores contained in the HAp during the filament making process, and can be supplemented by making the PLA and HAp particle sizes as small as possible.

If the extrusion temperature is less than 170 ° C, the melt of the raw material may be insufficient to cause difficulty in forming filaments. On the other hand, if the extrusion temperature is higher than 215 ° C, the processability and mechanical The physical properties may be deteriorated.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these embodiments.

Example

Experimental rats (male, 8 weeks old) were prepared and subjected to respiratory anesthesia using a ventilator. At this time, isoflurane was used as the anesthetic agent, and its capacity was 4% at the initial anesthesia and 2.5% at the maintenance. Hair removal was performed at the position where the bone anchoring device was inserted, and the skin was disinfected using alcohol cotton and betadine. The outer skin and fascia of the thighs of the rat were cut and the femur of the rat was cut with a dental carving machine (hand cutter: circular disc of 1 cm in diameter) to make a bone defect area of 1 mm in size.

10 g of pellet-shaped PLA (Nature Works LLC, Ingeo ^® 3001D) was firstly pulverized in a blender. At this time, the average size of pulverized PLA was 32 탆.

0.3 g of HAp in powder form was mixed into a blender containing pulverized PLA, and the blender was operated for 2 minutes to be secondarily pulverized.

The PLA and the HAp, which have been subjected to the second pulverization step, And a filament having a diameter of 1.75 mm and a length of 30 cm was produced at an extrusion temperature of 170 ° C. A cross-sectional photograph (A) and a longitudinal section photograph (B) of the filament thus produced are shown in Fig. At this time, as the filament maker, an in-house manufactured by using open source was used.

&Lt; Preparation of bone fixation device >

CT scans of 1 mm intervals were obtained by computer tomography (CT) of the entire femur of the prepared experimental rats.

The captured CT DICOM image was expressed as a VR image using a program called InVesalius. It is converted into SSD image and saved as STL file. The stored STL file was loaded in the 3D MAX 2014 program and a clip model of the bone anchoring device to be mounted on the bone defect site was prepared. At this time, the thickness of the clip model is 1.45 cm. The clip model thus produced is shown in Fig.

Then, the created clip model was converted through the G-code conversion program creator K.

The fabricated filament was supplied to a 3D printer (3DKON PLUS, Inc.) and output in accordance with G-codes to produce a bone-fixing device. At this time, the output speed was 20 mm / sec and the nozzle diameter was 0.2 mm. FIG. 3 shows a bone fixation device manufactured in this manner.

Comparative Example

A bone fixation device was manufactured in the same manner as in the above example except that a filament for a 3D printer was produced according to the following method.

Ten grams of PLA (Nature Works LLC, Ingeo ^® 3001D) in the form of pellets was placed in a self-made filament maker and a filament having a diameter of 1.75 mm and a length of 30 cm was produced at an extrusion temperature of 170 ° C.

Assessment Methods

1. SEM-EDS Analysis

The bone fixation device manufactured according to Examples and Comparative Examples was cut and coated with Au-Pd, and then cross section of the bone fixation device was observed using a scanning electron microscope (manufacturer: Carl Zeiss Germany, Model: RUPRA55V VP-FESEM) And the surface was analyzed with the same microscope to show in FIGS. 4 and 5.

4 shows a cross-sectional SEM photograph (top) and an EDS analysis result (bottom) of the bone fixation device manufactured according to the embodiment, and FIG. 5 shows a cross-sectional SEM photograph of the bone fixation device manufactured according to the comparative example Phase) and the EDS analysis result (bottom).

The cross-sectional SEM photographing was carried out in order to check whether the bent portion of the outputted bone fixing device was correctly output. Referring to FIGS. 4 and 5, it can be seen that both curved surfaces of both of the two bone fixing devices are accurately displayed. In addition, it can be seen that the thickness of the bone fixation device on the SEM photograph is about 1.45 cm, which is the same as the thickness of the clip model shown in Fig. 4 and FIG. 5, it can be confirmed that voids are observed in the cross section of FIG. 4. This is because in the process of filament production, air is injected into fine gaps between PLA and HAp particles, , Which can be supplemented by reducing the PLA and HAp particle size.

In addition, the EDS analysis was performed to determine whether HAp was distributed on the surface of the bone fixation device. In FIG. 4, phosphorus and calcium (calcium) were analyzed in addition to carbon and oxygen On the other hand, in FIG. 5, only carbon and oxygen are confirmed. As a result, it can be seen that HAp is outputted like PLA without sticking to the inside of the nozzle due to the characteristic of the 3D printer output process which is outputted to the nozzle.

2. Compressive Strength and Compressive strain measurement

A compressive strength machine (manufactured by Qmesys Korea, model name: QM100S) was used to measure the compressive strength and strain of the bone fixation specimen prepared according to Examples and Comparative Examples. In order to measure the strength of the teeth of the bone fixation device, it was measured vertically and averaged with a limiting load of 200 Kgf and a limited displacement of 10 mm. Then, the bone-anchoring apparatus, which was allowed to stand for 24 hours at a temperature of 24 ° C ± 2 ° C and a humidity of 40%, was attached to a compressive strength device, and then the compressive force was measured. The crosshead speed was 5 mm / min when measuring compressive strength. The compressive strength was evaluated by the maximum stress until the specimen was broken and measurement was impossible, and the degree of deformation until the specimen was broken was expressed by the strain (see Equation 1 below). The compression test was carried out using five bone fixation specimens prepared according to Examples and Comparative Examples, and the obtained values were statistically processed.

Strain (%) = [(L ₁ - L ₀ ) / L ₀ ] × 100 ... (One)

In the above equation (1), L ₁ represents the height of the bone anchoring device after compression, and L ₀ represents the height of the bone anchoring device before compression.

Table 1 and FIG. 6 show the compressive strength and strain of the bone fixation device manufactured according to the above Examples and Comparative Examples.

Filament configuration Compressive strength Strain Example PLA + HAp 11.18 MPa 0.7% Comparative Example PLA 12.86 MPa 0.7%

Referring to Table 1 and FIG. 6, it can be seen that the bone anchoring device manufactured according to the embodiment exhibits a similar level of compressive strength and strain to that of the bone anchoring device manufactured according to the comparative example. It can be seen that the internal voids observed in the SEM image (see FIG. 4) do not significantly affect the compressive strength or strain.

3. Cell Proliferation Test

The cell proliferation test method for examining the cell affinity of the bone fixation device manufactured according to the above-described Examples and Comparative Examples was performed with respect to the filament used for each test.

Specifically, a circular sample having a diameter of 6 mm and a height of 0.5 mm was prepared from filaments prepared according to the above Examples and Comparative Examples, and each sample was placed in a 96-well cell culture plate, Bone Marrow Stem Cell (BMSC) was inoculated and cultured for 7 days. After 7 days of culture, MTT (3- (4,5-Dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide) solution (5 mg / ml) was added to each sample in order to examine the cytotoxicity of each filament. And incubated in an incubator for 2 hours. Then, each of the above samples was transferred to a 1.5 ml tube, and 1 ml of dimethyl sulfoxide (DMSO, Sigma) solution was added thereto to dissolve the solution in an ultrasonic washing machine until the purple crystals were completely dissolved. After the purple crystals were completely dissolved, the solution was dispensed into 96 wells in an amount of 100 μL, and the resultant solution was added to the solution at 540 nm using an enzyme-linked immunosorbent assay (ELISA) plate reader (Molecular Devices Corp., Sunnyvale, California, USA) Absorbance was measured.

FIG. 7 is a graph showing MTT analysis results of filaments prepared according to Examples and Comparative Examples. In the graph, the abscissa indicates the absorbance and the ordinate indicates the absorbance. MTT analysis is a method for measuring the number of living cells using the ability of intracellular mitochondria to reduce the yellow water-soluble substrate MTT tetrazolium to purple, non-aqueous MTT formazan crystals by dehydrogenase action . The higher the number of living cells, the higher the absorbance measured at 540 nm and thus the cell affinity can be confirmed.

7, the filament samples (PLA + HAp) according to the examples show higher absorbance than the filament samples (PLA) of the comparative example at 1, 3, and 7 days, so that the cell affinity is higher . This is due to the fact that HAp fuses well in tissue and in vivo.

4. Animal experiments

Using the bone fixation device manufactured according to the example, two broken femurs of the experimental rat were joined together, and the incision was closed. FIG. 8 shows a procedure of implanting a bone fixation device into a laboratory mouse. FIGS. 9 and 10 are photographs showing bone grafting devices implanted in the experimental rats at different angles, respectively.

FIG. 11A shows a CT image of a mouse's femur taken 8 weeks after insertion of a bone anchoring device, and B, C, and D show a modified InVesalius CT image obtained by changing the CT image to a VR image at various angles As shown in Fig. Referring to FIG. 11, it can be clearly seen that the cut-off image is clearly seen during the operation and that the two cut femurs are connected to the date. This confirms that the bone anchoring device is fixed to the femur size.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the invention is not limited to the disclosed exemplary embodiments but is to be construed as being limited only by the appended claims. Should be construed as being included in the scope of the present invention.

Claims

A method of manufacturing a bone fixation device using a 3D printing method,
A tomographic imaging step of acquiring tomographic image data by photographing a fracture site of a patient with a medical tomographic imaging apparatus,
A 3D modeling step of generating 3D data for a bone anchoring device corresponding to the fracture site based on the image data,
A raw material supplying step for supplying filaments containing polylactic acid (PLA) and hydroxyapatite (HA) to a 3D printer; and
And a bone fixation device for 3D printing the bone fixation device through the 3D printer using the 3D data.

The method according to claim 1,
The medical tomographic imaging apparatus includes a computer tomography (CT) apparatus, a magnetic resonance imaging (MRI) apparatus, a positron emission tomography (PET) apparatus, and a single photon emission a computed tomography (SPECT) device, and a computed tomography (SPECT) device.

The method according to claim 1,
Wherein the content of the hydroxyapatite in the filament is 1 to 15 parts by weight based on 100 parts by weight of the polylactic acid.

The method according to claim 1,
Wherein the diameter of the filament is 1.0 to 2.0 mm.

The method according to claim 1,
Wherein the nozzle diameter of the 3D printer is 0.2 to 0.4 mm.

A bone anchoring device manufactured by the method for manufacturing a bone anchor according to any one of claims 1 to 5.

A filament for a 3D printer used in a method of manufacturing a bone anchor according to any one of claims 1 to 5.

A method for producing a filament for a 3D printer according to claim 7,
A mixing step of mixing polylactic acid with hydroxyapatite and
And extruding the polylactic acid and the hydroxyapatite to form a filament.

9. The method of claim 8,
Wherein the polylactic acid is in the form of pellets.

10. The method of claim 9,
Further comprising a first pulverizing step of pulverizing the polylactic acid having a pellet shape before the mixing step.

11. The method of claim 10,
Wherein the average size of the polylactic acid after the first pulverization step is 5 to 50 mu m.

9. The method of claim 8,
Wherein the hydroxyapatite is in powder form in the mixing step.

9. The method of claim 8,
Wherein the hydroxyapatite is mixed in an amount of 1 to 15 parts by weight based on 100 parts by weight of the polylactic acid in the mixing step.

9. The method of claim 8,
Further comprising, after the mixing step, a second pulverization step of pulverizing the polylactic acid and the hydroxyapatite.

9. The method of claim 8,
And the extrusion temperature in the extrusion step is 170 to 215 ° C.