CN110640950A - Method for manufacturing individualized intestinal fistula stent and applicable die thereof - Google Patents

Method for manufacturing individualized intestinal fistula stent and applicable die thereof Download PDF

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Publication number
CN110640950A
CN110640950A CN201910902856.0A CN201910902856A CN110640950A CN 110640950 A CN110640950 A CN 110640950A CN 201910902856 A CN201910902856 A CN 201910902856A CN 110640950 A CN110640950 A CN 110640950A
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CN
China
Prior art keywords
shell
inner core
mold
intestinal
intestinal fistula
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Granted
Application number
CN201910902856.0A
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Chinese (zh)
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CN110640950B (en
Inventor
任建安
黄金健
蒋运罡
李宗安
吴秀文
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General Hospital Of Eastern War Zone Of Chinese People's Liberation Army
Eastern Theater General Hospital of PLA
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General Hospital Of Eastern War Zone Of Chinese People's Liberation Army
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C39/00—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor
    • B29C39/02—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor for making articles of definite length, i.e. discrete articles
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F5/00—Orthopaedic methods or devices for non-surgical treatment of bones or joints; Nursing devices; Anti-rape devices
    • A61F5/44—Devices worn by the patient for reception of urine, faeces, catamenial or other discharge; Portable urination aids; Colostomy devices
    • A61F5/445—Colostomy, ileostomy or urethrostomy devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C39/00—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor
    • B29C39/22—Component parts, details or accessories; Auxiliary operations
    • B29C39/38—Heating or cooling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
    • B29C64/10—Processes of additive manufacturing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y10/00—Processes of additive manufacturing

Abstract

The invention relates to a method for manufacturing an individual intestinal fistula stent and a suitable mould thereof, wherein the method for manufacturing the individual intestinal fistula stent comprises the following steps: 1) performing meglumine contrast to obtain the size of a far end intestinal canal and a near end intestinal canal; 2) designing a mould by using graphic design software; 3) preparing a die by adopting 3D printing or metal powder printing; 4) and preparing the bracket by adopting a silica gel injection mold. The mould applicable to the method comprises an outer shell and an inner core; the shell and the inner core are both in an inverted L shape; the inner core is disposed within the outer shell such that an injection mold cavity is formed therebetween. The invention has reasonable design and simple operation, can ensure that the height of the prepared bracket is consistent with the anatomical structure of the intestinal fistula of a patient, and can use silica gel to manufacture the bracket, so that the bracket has better elasticity and fully meets the requirement of the intestinal fistula treatment.

Description

Method for manufacturing individualized intestinal fistula stent and applicable die thereof
Technical Field
The invention relates to a manufacturing method of a medical apparatus, in particular to a manufacturing method of an intestinal fistula stent and a mold suitable for the method, and specifically relates to a manufacturing method of an individual intestinal fistula stent and a mold suitable for the method.
Background
At present, in the treatment of intestinal fistula, a bracket is mainly used for temporarily repairing a damaged intestinal canal to prevent intestinal juice from overflowing. Most of the current brackets are produced in a standardized way, and the specifications and the models are limited. The individual conditions of patients are different, so that the stent can not be well matched with the intestinal fistula of the patients frequently, and the using effect is influenced. Therefore, improvements are urgently needed in order to meet the needs of individualized intestinal fistula treatment.
Disclosure of Invention
The invention aims to provide a method for manufacturing an individualized intestinal fistula stent and an applicable mold thereof aiming at the problems in the intestinal fistula treatment at present, so that the manufactured stent is highly consistent with the anatomical structure of the intestinal fistula of a patient, has better elasticity and fully meets the requirement of the intestinal fistula treatment.
The technical scheme of the invention is as follows:
a method for manufacturing an individualized intestinal fistula stent comprises the following steps:
1) carrying out meglumine diathesis on a patient with intestinal fistula, carrying out three-dimensional reconstruction on an angiography image by using high-resolution CT (computed tomography), knowing an anatomical structure around a fistula orifice, and acquiring the size of a far-end intestinal canal and a near-end intestinal canal;
2) using graphic design software to design a mould and converting the mould into an STL file;
3) preparing a die by adopting 3D printing or metal powder printing;
4) mixing the food-grade silica gel A and the silica gel B according to the ratio of 0.1:1 to 10:1, injecting the mixture into a mold, placing the mixture in an oven at 100 ℃ for 15 to 20 minutes, or standing the mixture at room temperature for 6 to 24 hours, and removing the mold after the silica gel is solidified to obtain the bracket.
Further, in the step 3), polylactic acid, polyurethane or polycaprolactone is selected for 3D printing.
Further, in the step 3), iron powder, titanium powder or aluminum powder is selected for metal powder printing.
In the step 4), the mixed silica gel is poured into any one of a 10mL syringe, a 20mL syringe or a 50mL syringe, and then is injected into a mold.
A mold suitable for individualized intestinal fistula scaffold fabrication, the mold comprising an outer shell and an inner core; the shell is in a reverse L-shaped cylinder shape, the upper end of the shell is closed, the lower end of the shell is open, the corner is in a circular arc shape, and the side wall of the shell is provided with an injection hole; the diameters of the two ends of the shell are the same or different; the shell is split into two halves along the axis of the shell, and the edge of the split part is provided with a flash; the flash is provided with corresponding screw holes, and the two halves of the shell can be connected through screws; the inner core is cylindrical, the shape of the inner core is the same as that of the outer shell, and a base is arranged at the lower end of the inner core; the inner core is arranged in the shell, and the upper end of the inner core is abutted against the upper end of the shell; the base blocks the lower port of the shell, so that an injection molding cavity is formed between the inner core and the shell.
Furthermore, a positioning column is arranged at the upper end of the inner core; a positioning groove is formed in the inner side of the upper end of the shell; the positioning column and the positioning groove are matched in position and size, so that the positioning column is inserted into the positioning groove, and the accuracy of the shape of the injection molding cavity is ensured.
Furthermore, a bulge is arranged on the base; the lower end of the shell is provided with a step-shaped groove; the sizes of the bulges and the grooves are matched with each other, so that the bulges can be clamped into the grooves to plug the lower port of the shell, and the base abuts against the lower end of the shell.
Furthermore, the injection holes are two and are respectively and correspondingly arranged on the side walls of the two half parts of the shell for injecting the mold material and exhausting.
The invention has the beneficial effects that:
the invention has reasonable design and simple operation, can ensure that the height of the prepared bracket is consistent with the anatomical structure of the intestinal fistula of a patient, and can use silica gel to manufacture the bracket, so that the bracket has better elasticity and fully meets the requirement of the intestinal fistula treatment.
Drawings
FIG. 1 is a schematic structural view of the mold core of the present invention.
Fig. 2 is a schematic structural view of a mold shell of the basic invention.
Wherein: 1-kernel; 2-a base; 3-projection; 4-a positioning column; 5-a housing; 6-screw hole; 7-flashing; 8-an injection hole; 9-positioning grooves; 10-a groove; 11-notch.
Detailed Description
The invention is further described below with reference to the figures and examples.
A method for manufacturing an individualized intestinal fistula stent comprises the following steps:
1) carrying out meglumine diathesis on a patient with intestinal fistula, carrying out three-dimensional reconstruction on an angiography image by using high-resolution CT (computed tomography), knowing an anatomical structure around a fistula orifice, and acquiring the size of a far-end intestinal canal and a near-end intestinal canal;
2) carrying out die design by using graphic design software such as 3D max software or solidwork software and the like, and converting into an STL file; the STL file may be recognized by 3D printers and metal powder printers;
3) preparing a die by adopting 3D printing or metal powder printing; wherein, polylactic acid, polyurethane or polycaprolactone can be selected for 3D printing; or, selecting iron powder, titanium powder or aluminum powder to print metal powder;
4) mixing food-grade silica gel A and silica gel B according to the proportion of 0.1:1 to 10:1, pouring the mixed silica gel into any one of a 10mL syringe, a 20mL syringe or a 50mL syringe, injecting the mixed silica gel into a mold, placing the mold in an oven at 100 ℃ for 15-20 minutes, or standing the mold at room temperature for 6-24 hours, and removing the mold after the silica gel is solidified to obtain the stent.
Preferably, in order to conveniently take out the bracket, the surface of the inner core of the mold can be coated with grease before injection molding; alternatively, after removal of the mold, the stent may be peeled from the core by cutting along one side of the stent.
As shown in fig. 1 and 2, a mold suitable for individualized fistula stent fabrication comprises an outer shell 5 and an inner core 1. The housing 5 is in the shape of an inverted L cylinder, the upper end of the housing is closed, the lower end of the housing is open, the corner is in the shape of an arc, and the sidewall of the housing is provided with an injection hole 8. The diameters of the two ends of the shell 5 are the same or different so as to adapt to the specific conditions at intestinal fistulas of different patients. The shell 5 is split in half along its axis and is provided with fins 7 at the edges of the split. The flash 7 is provided with corresponding screw holes 6, and the two halves of the housing 5 can be connected together by screws. The inner core 1 is cylindrical, the shape of the inner core is the same as that of the outer shell 5, and the lower end of the inner core is provided with a base 2. The inner core 1 is arranged in the outer shell 5, the upper end of the inner core abuts against the upper end of the outer shell 5, and the base 2 blocks the lower port of the outer shell 5, so that an injection molding cavity is formed between the inner core 1 and the outer shell 5. Preferably, the diameters of the upper end and the lower end of the inner core 1 are respectively 1-3mm smaller than the inner diameters of the upper end and the lower end of the outer shell. The angles of the corners of the core 1 and the shell 5 are the same.
The upper end of the inner core 1 is provided with a positioning column 4. And a positioning groove 9 is formed in the inner side of the upper end of the shell 5. The positioning column 4 is matched with the positioning groove 9 in position and size, so that the positioning column 4 is inserted into the positioning groove 9, and the accuracy of the shape of the injection molding cavity is ensured.
The base 2 is provided with a bulge 3. The lower end of the shell 5 is provided with a step-shaped groove 10. The sizes of the protrusion 3 and the groove 10 are matched with each other, so that the protrusion 3 can be clamped into the groove 10 to plug the lower port of the shell 5, and the base 2 is abutted against the lower end of the shell 5.
The two injection holes 8 are correspondingly arranged on the side walls of the two halves of the shell 5 respectively and used for injecting the mold material and exhausting air.
Still be equipped with a plurality of breachs 11 on the base 2, can conveniently be right through bolt etc. base 2 is fixed.
The parts not involved in the present invention are the same as or can be implemented using the prior art.

Claims (8)

1. A method for manufacturing an individual intestinal fistula stent is characterized by comprising the following steps: the method comprises the following steps:
1) carrying out meglumine diathesis on a patient with intestinal fistula, carrying out three-dimensional reconstruction on an angiography image by using high-resolution CT (computed tomography), knowing an anatomical structure around a fistula orifice, and acquiring the size of a far-end intestinal canal and a near-end intestinal canal;
2) using graphic design software to design a mould and converting the mould into an STL file;
3) preparing a die by adopting 3D printing or metal powder printing;
4) mixing the food-grade silica gel A and the silica gel B according to the ratio of 0.1:1 to 10:1, injecting the mixture into a mold, placing the mixture in an oven at 100 ℃ for 15 to 20 minutes, or standing the mixture at room temperature for 6 to 24 hours, and removing the mold after the silica gel is solidified to obtain the bracket.
2. The method of claim 1, wherein the method further comprises: in the step 3), polylactic acid, polyurethane or polycaprolactone is selected for 3D printing.
3. The method of claim 1, wherein the method further comprises: and in the step 3), iron powder, titanium powder or aluminum powder is selected for metal powder printing.
4. The method of claim 1, wherein the method further comprises: in the step 4), the mixed silica gel is poured into any one of a 10mL syringe, a 20mL syringe or a 50mL syringe, and then is injected into a mold.
5. The utility model provides a mould suitable for individuation intestines fistula support preparation, characterized by: the mold comprises an outer shell and an inner core; the shell is in a reverse L-shaped cylinder shape, the upper end of the shell is closed, the lower end of the shell is open, the corner is in a circular arc shape, and the side wall of the shell is provided with an injection hole; the diameters of the two ends of the shell are the same or different; the shell is split into two halves along the axis of the shell, and the edge of the split part is provided with a flash; the flash is provided with corresponding screw holes, and the two halves of the shell can be connected through screws; the inner core is cylindrical, the shape of the inner core is the same as that of the outer shell, and a base is arranged at the lower end of the inner core; the inner core is arranged in the shell, and the upper end of the inner core is abutted against the upper end of the shell; the base blocks the lower port of the shell, so that an injection molding cavity is formed between the inner core and the shell.
6. The mold suitable for individualized intestinal fistula stent fabrication according to claim 5, wherein: the upper end of the inner core is provided with a positioning column; a positioning groove is formed in the inner side of the upper end of the shell; the positioning column and the positioning groove are matched in position and size, so that the positioning column is inserted into the positioning groove, and the accuracy of the shape of the injection molding cavity is ensured.
7. The mold suitable for individualized intestinal fistula stent fabrication according to claim 5, wherein: a bulge is arranged on the base; the lower end of the shell is provided with a step-shaped groove; the sizes of the bulges and the grooves are matched with each other, so that the bulges can be clamped into the grooves to plug the lower port of the shell, and the base abuts against the lower end of the shell.
8. The mold suitable for individualized intestinal fistula stent fabrication according to claim 5, wherein: the injection holes are two and are respectively and correspondingly arranged on the side walls of the two half parts of the shell and used for injecting the mold material and exhausting.
CN201910902856.0A 2019-09-24 2019-09-24 Method for manufacturing individualized intestinal fistula stent and applicable die thereof Active CN110640950B (en)

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Cited By (1)

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Publication number Priority date Publication date Assignee Title
CN115091776A (en) * 2022-06-29 2022-09-23 大连理工大学 Personalized silica gel valve and manufacturing method of calcified silica gel valve physical model

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