TWI859523B - Method for preparing a filler body - Google Patents

Abstract

A microchannel scaffold structure which is composed of a composite material is provided. The composite material includes: a biodegradable natural polymer material; and a biodegradable ceramic material. Moreover, the microchannel scaffold structure has at least one microchannel, and the microchannel is directional by extending toward a bottom surface of the microchannel scaffold in a manner that a channel width thereof decreases toward the bottom surface, and extends to and ends at the bottom surface, and has a bottom opening on the bottom surface.

Description

Method for preparing a filling body

The present disclosure relates to a support structure, and in particular to a microchannel support structure and its application and preparation method.

Tooth decay refers to the phenomenon of tooth decomposition caused by bacterial activity. When tooth decay is severe, causing oral bacteria to enter the dental pulp cavity and cause inflammation and pain of the dental pulp nerve, one of the common treatment methods is tooth root canal treatment.

Generally speaking, root canal treatment is achieved by removing the inflamed and necrotic pulp tissue in the pulp cavity. However, since root canal treatment requires the removal of the nerves in the pulp cavity, the tooth will never be able to recover. Therefore, there is an urgent need for a new method of treating caries or severe caries and/or tooth filling materials that can avoid the removal of nerves in the pulp cavity so that the dentin and pulp tissue can be reconstructed.

The present disclosure provides a microchannel support structure, which is composed of a composite material. The composite material includes: a biodegradable natural polymer material; and a biodegradable ceramic material. In addition, the microchannel support structure has at least one microchannel, and the microchannel has directionality by extending toward a bottom surface of the microchannel support structure in a manner that its channel width decreases toward the bottom surface, and extends to the bottom surface, and has an opening on the bottom surface.

The present disclosure also provides a method for preparing a microchannel support structure, comprising: (a) adding an alcohol solvent or an acid solvent into a system and performing a cooling process to make the temperature of the system lower than room temperature; (b) after the cooling process, adding a biodegradable natural polymer material into the system to form a mixed solution with the alcohol solvent or the acid solvent, wherein the content of the biodegradable natural polymer material in the mixed solution is about 0.1-10% (w/v); (c) in the system, performing a static process on the mixed solution; (d) after the static process, in the system (e) subjecting the mixed solution to a first homogenization process to obtain a slurry; (f) adding a biodegradable ceramic material to the system to form a mixture with the slurry, wherein the content of the biodegradable ceramic material in the mixture is about 0.1-10% (w/v); (g) subjecting the mixture to a second homogenization process to obtain a homogenate; (h) subjecting the homogenate to a centrifugation process after the centrifugation process, and (i) subjecting the homogenate to a drying process after the freezing process to obtain the microchannel support structure. The drying process comprises: (1) cooling a drying plate to a temperature of about -50 to 0°C; (2) placing the homogenate on the drying plate after cooling the drying plate to a temperature of about -50 to 0°C; (3) after placing the homogenate on the drying plate, performing a first stage microchannel support structure vacuum drying on the homogenate, wherein in the first stage microchannel support structure vacuum drying, the plate temperature is about -50 to 0°C; 50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the time for performing the first stage of vacuum drying of the microchannel support structure is about 1-24 hours; (4) after the first stage of vacuum drying of the microchannel support structure, the homogeneous material is subjected to a second stage of vacuum drying of the microchannel support structure, wherein in the second stage of vacuum drying of the microchannel support structure, the temperature of the shelf is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the execution time is about 1 to 24 hours; (5) after the second stage of vacuum drying of the microchannel support structure, the homogeneous material is subjected to a third stage of vacuum drying of the microchannel support structure, wherein in the third stage of vacuum drying of the microchannel support structure, the temperature of the shelf is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50Pa, and the execution time is about 1-24 hours; and (6) after the third stage microchannel support structure vacuum drying, the homogenate is subjected to a fourth stage microchannel support structure vacuum drying, wherein in the fourth stage microchannel support structure vacuum drying, the shelf temperature is about 0 to 50°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50Pa, and the execution time is about 1-24 hours. In addition, the microchannel support structure has at least one microchannel, and the microchannel has directionality by extending toward a bottom surface of the microchannel support structure in a manner that its channel width decreases toward the bottom surface, and extends to the bottom surface, and has an opening on the bottom surface.

The present disclosure also provides a filling body, including a double-layer support structure, wherein the double-layer structure includes: a microchannel support structure; and a porous support structure. The microchannel support structure is composed of a composite material, and the composite material includes: a first biodegradable natural polymer material; and a biodegradable ceramic material. The porous support structure is composed of a single type of material, and the single type of material includes: a second biodegradable natural polymer material. A bottom surface of the microchannel support is bonded to a top surface of the porous support structure. The microchannel support structure has at least one microchannel, and the microchannel has directionality by extending toward a bottom surface of the microchannel support structure in a manner that its channel width decreases toward the bottom surface, and extends to the bottom surface, and has an opening on the bottom surface. Furthermore, the porous support structure has at least one hole, and the hole has a diameter larger than the opening.

The present disclosure further provides a method for preparing a filling body, comprising: (A) preparing a microchannel support structure; (B) preparing an uncured body of a porous support structure; (C) directly contacting the bottom surface of the microchannel support structure with the uncured body of the porous support structure to form a double-layer stack; and (D) subjecting the double-layer stack to a freeze-drying process to form the filling body. Step (A) comprises: (A-1) subjecting a first alcohol solvent or an acidic solvent to a first cooling process to make the temperature of the first alcohol solvent or the acidic solvent lower than room temperature; (A-2) after the first cooling process, adding a first biodegradable natural polymer material to the first alcohol solvent or the acidic solvent to form a mixed solution, wherein the content of the first biodegradable natural polymer material in the first mixed solution is about 0.1-10% (w/v); (A-3) subjecting the first mixed solution to a first static process; (A-4) subjecting the first mixed solution to a first saturation process after the first static process; (A-5) adding a biodegradable ceramic material to the first slurry to form a mixture, wherein the content of the biodegradable ceramic material in the mixture is about 0.1-10% (w/v); (A-6) subjecting the mixture to a second homogenization process to obtain a homogenate; (A-7) subjecting the homogenate to a first centrifugation process; (A-8) after the first centrifugation process, subjecting the homogenate to a freezing process; (A-9) after the freezing process, subjecting the homogenate to a microchannel support structure drying process to obtain the microchannel support structure. The microchannel support structure drying process includes: (A-9-1) cooling a first drying plate to a temperature of about -50 to 0°C; (A-9-2) placing the homogenate on the drying plate after cooling the drying plate to a temperature of about -50 to 0°C; (A-9-3) after placing the homogenate on the first drying plate, performing a first stage microchannel support structure vacuum drying on the homogenate, wherein the microchannel support structure is dried in the first stage. During the vacuum drying of the microchannel support structure, the temperature of the shelf is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the time for performing the first stage of vacuum drying of the microchannel support structure is about 1-24 hours; (A-9-4) after the first stage of vacuum drying of the microchannel support structure, the homogeneous material is subjected to a second stage of vacuum drying of the microchannel support structure, wherein during the second stage of vacuum drying of the microchannel support structure, the The temperature of the plate is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours; (A-9-5) after the second stage of vacuum drying of the microchannel support structure, the homogeneous material is subjected to a third stage of vacuum drying of the microchannel support structure, wherein in the third stage of vacuum drying of the microchannel support structure, the temperature of the plate is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours; The vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours; and (A-9-6) after the third stage microchannel support structure vacuum drying, the homogenate is subjected to a fourth stage microchannel support structure vacuum drying, wherein in the fourth stage microchannel support structure vacuum drying, the shelf temperature is about 0 to 50°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours. Step (B) comprises: (B-1) subjecting a second alcohol solvent or an acidic solvent to a second cooling process to make the temperature of the second alcohol solvent or the acidic solvent lower than room temperature; (B-2) after the second cooling process, adding a second biodegradable natural polymer material to the second alcohol solvent or the acidic solvent to form a second mixed solution, wherein the content of the second biodegradable natural polymer material in the second mixed solution is about 0.1-10% (w/v); (B-3) subjecting the second mixed solution to a second static process; (B-4) after the second static process, subjecting the second mixed solution to a third homogenization process to obtain a slurry; and (B-5) subjecting the slurry to a second centrifugation process to form an uncured body of the porous scaffold structure. Furthermore, step (D) includes: (D-1) cooling a second drying plate to a temperature of about -50 to 0°C; (D-2) placing the double-layer stack on the drying plate after cooling the second drying plate to a temperature of about -50 to 0°C; (D-3) performing a third static process on the double-layer stack after stacking the double-layer stack on the second drying plate; (D-4) performing a third static process on the double-layer stack after the third static process. a first stage of vacuum drying of the filling body, wherein in the first stage of vacuum drying of the filling body, the temperature of the shelf is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the time for performing the first stage of vacuum drying of the filling body is about 1-24 hours; (D-5) after the first stage of vacuum drying of the filling body, performing a second stage of vacuum drying of the filling body on the double-layer stack, wherein in the second stage (D-6) after the second stage vacuum drying of the filling body, the double-layer stack is subjected to a third stage vacuum drying of the filling body, wherein in the third stage vacuum drying of the filling body, the temperature of the frozen plate is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours; (D-7) after the second stage vacuum drying of the filling body, the double-layer stack is subjected to a third stage vacuum drying of the filling body, wherein in the third stage vacuum drying of the filling body, the temperature of the frozen plate is about -50 to 0°C, the condensation temperature is about - 90 to 0°C, the vacuum degree is about 1 to 50Pa, and the execution time is about 1-24 hours; and (D-7) after the third stage filling body vacuum drying, the double-layer stack is subjected to a fourth stage filling body vacuum drying, wherein in the fourth stage filling body vacuum drying, the temperature of the plate is about 0 to 50°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50Pa, and the execution time is about 1-24 hours. The formed filling body has the microchannel support and a porous support structure formed by the uncured body of the porous support structure, and a bottom surface of the microchannel support is bonded to a top surface of the porous support structure. The microchannel support structure has at least one microchannel, and the microchannel has directionality by extending toward a bottom surface of the microchannel support structure in a manner that its channel width decreases toward the bottom surface, and extends to the bottom surface, and has an opening on the bottom surface. In addition, the porous support structure has at least one hole, and the hole diameter is larger than the opening.

In order to make the above and other purposes, features, and advantages of the present invention more clearly understood, the following is a detailed description of the preferred embodiment with accompanying diagrams as follows:

100, 401: Microchannel support structure

100BS: Bottom surface of microchannel support structure

101: Microchannel

101W: Width of microchannel

101BO: The opening of the microchannel 101 on the bottom surface 100BS of the microchannel support structure

2000, 400: Filling body

200, 403: porous scaffold structure

200TS: Top surface of porous support structure

201: Hole

Figure 1 shows a schematic diagram of the microchannel support structure disclosed herein.

Figure 2 shows a schematic diagram of the structure of the filling body disclosed in the present invention.

Figure 3A shows a 40X scanning electron microscope image of a microchannel support structure of an embodiment of the present disclosure. The dotted arrow shows the direction of the microchannel.

FIG. 3B shows a 100X scanning electron microscope image of a microchannel support structure of an embodiment of the present disclosure. The dashed box shows the location of the microchannel, and the dashed arrow shows the width of the microchannel.

Figure 4 shows a micro computed tomography (Micro-CT) scan of a filling body according to an embodiment of the present disclosure.

The present disclosure provides a microchannel support structure having a special structural design that can prevent an undesirable substance and/or cell from entering therein from a specific direction.

The microchannel scaffold structure disclosed above can be applied to tissue engineering and/or tissue regeneration and other related applications, but is not limited thereto. The above-mentioned tissue engineering and/or tissue regeneration related applications may include, but are not limited to, the reconstruction of soft tissue and/or hard tissue, for example, the reconstruction of dentin.

FIG. 1 shows a schematic diagram of a microchannel support structure disclosed in the present invention. See FIG. 1. The microchannel support structure 100 may have at least one microchannel 101. The microchannel 101 may have directionality by extending toward the bottom surface 100BS of the microchannel support structure 100 in a manner that its channel width W decreases toward a bottom surface 100BS of the microchannel support structure 100, and extends to the bottom surface 101BS of the microchannel support structure 100, and has an opening 101BO on the bottom surface 100BS.

In one embodiment, in addition to the at least one microchannel 101, the microchannel support structure 100 may further include at least one hole (not shown) on its surface and/or inside. The hole is not directional. Moreover, the shape of the hole may be regular or irregular without any particular limitation. Moreover, the shapes and sizes of different holes may be the same or different without any particular limitation.

The microchannel support structure 100 disclosed herein can prevent an undesirable substance/cell from entering from the bottom thereof by designing the width W of the microchannel 101 therein to decrease toward its bottom surface.

The microchannel 101 in the microchannel support structure 100 disclosed herein can extend to the bottom surface 100BS of the microchannel support structure 100 in a straight line or a non-straight line manner without any particular limitation. In one embodiment, the microchannel in the microchannel support structure disclosed herein extends to the bottom surface 100BS of the microchannel support structure 100 in a straight line manner.

Furthermore, the width of the microchannel in the microchannel support structure disclosed above can be designed according to the field and/or situation in which the microchannel support structure is to be applied, and there is no special limitation, as long as the width of the microchannel decreases toward the bottom surface of the microchannel support structure, and an undesirable substance/cell in the field and/or situation of the desired application can be prevented from entering the microchannel support structure through the microchannel opening at the bottom surface of the microchannel support structure.

The width of the widest part of the microchannel in the microchannel support structure disclosed above may be about 50-200 μm, for example, about 50-100 μm, about 100-150 μm, about 150-200 μm, about 50 μm, about 55 μm, about 60 μm, about 70 μm, about 75 μm, about 80 μm, about 90 μm, about 100 μm, about 120 μm, about 125 μm, about 150 μm, about 200 μm, etc., but is not limited thereto. Furthermore, the width of the narrowest part of the microchannel in the microchannel stent structure disclosed above can be about 10-50μm, such as about 10-20μm, about 20-40μm, about 40-50μm, about 10μm, about 15μm, about 20μm, about 25μm, about 30μm, about 35μm, about 40μm, about 45μm, about 49μm, about 50μm, etc. In one embodiment, the microchannel stent structure disclosed above is applied to dentin regeneration, and the width of the widest part of the microchannel in the microchannel stent structure can be about 80-90μm, and the width of the narrowest part of the microchannel in the microchannel stent structure can be about 30-40μm.

Similarly, the size of the opening of the microchannel in the microchannel support structure disclosed above on the bottom surface of the microchannel support structure can be designed according to the intended application field and/or context of the microchannel support structure, and there is no special limitation, as long as the opening of the microchannel on the bottom surface of the microchannel support structure is extended toward the bottom surface of the microchannel support structure in a manner that decreases according to the width of the microchannel toward the bottom surface of the microchannel support structure, and an opening formed on the bottom surface of the microchannel support structure can be prevented from an undesirable substance/cell in the intended application field and/or context from entering the microchannel from the bottom surface of the microchannel support structure through the bottom opening of the microchannel, but a desired substance/cell in the intended application field and/or context can be allowed to enter the microchannel from the bottom surface of the microchannel support structure through the bottom opening of the microchannel.

The size of the opening of the microchannel in the microchannel support structure disclosed herein on the bottom surface of the microchannel support structure may be about 0.1-1.0μm, such as about 0.1-0.3μm, about 0.3-0.7μm, about 0.7-1.0μm, about 0.1μm, about 0.2μm, about 0.3μm, about 0.4μm, about 0.5μm, about 0.6μm, about 0.7μm, about 0.8μm, about 0.9μm, about 1.0μm, etc., but not limited thereto.

In one embodiment, the size of the opening of the microchannel in the microchannel support structure disclosed herein on the bottom surface of the microchannel support structure may be larger than the size of an ion but smaller than the size of a cell, so as to allow the above ions to enter the microchannel from the above opening but prevent the above cells from entering the microchannel from the above opening. The ions described herein may include, but are not limited to, calcium ions, phosphorus ions, etc., or any combination thereof. The cells described herein may include, but are not limited to, undifferentiated cells, fibroblasts, immune cells, etc., or any combination thereof. In a specific embodiment, the cells described herein may include cells contained in dental pulp tissue, such as undifferentiated cells, fibroblasts, immune cells, etc., or any combination thereof.

In one embodiment, the microchannel scaffold structure disclosed above is applied to dentin regeneration, and the size of the opening of the microchannel on the bottom surface of the microchannel scaffold structure is larger than the size of calcium ions but smaller than the size of cells contained in the dental pulp tissue, so as to allow calcium ions to enter the microchannel from the opening, but prevent cells contained in the dental pulp tissue from entering the microchannel from the opening.

In addition, the appearance shape of the microchannel support structure disclosed above can also be designed according to the field and/or situation in which the microchannel support structure is to be applied, without special restrictions. Examples of the appearance shape of the microchannel support structure may include, but are not limited to, layers, columns, pyramids, blocks, etc. In addition, the above-mentioned columns may include, but are not limited to, cylinders, triangular columns, square columns, polygonal columns, etc. The above-mentioned pyramids may include, but are not limited to, cones, triangular pyramids, tetrahedral pyramids, polygonal pyramids, etc. In one embodiment, the microchannel support structure disclosed above is used for regeneration and/or reconstruction of dentin in a tooth, and the appearance shape of the microchannel support structure is a cylinder. In this embodiment, the use scenario may be to fill the microchannel support structure disclosed herein into the groove or hole of a tooth with damaged dentin and a groove or hole. Since the structure of the microchannel in the microchannel support structure disclosed herein is mainly designed with reference to the arrangement of the dentin tissue structure, and the calcium ions having the effect of hardening the support structure can enter the microchannel support structure through the microchannel, after the microchannel support structure disclosed herein is filled into the groove or hole of the tooth with damaged dentin, the calcium ions entering the microchannel structure through the microchannel in the microchannel structure will harden the support structure and achieve dentin regeneration and/or reconstruction in the tooth.

Similarly, the appearance dimensions of the microchannel support structure disclosed above can also be designed according to the field and/or situation in which the microchannel support structure is to be applied, without any special restrictions. In addition, the appearance dimensions of the microchannel support structure and the appearance shape of the microchannel support structure can be designed based on each other, but are not limited to this.

The thickness of the microchannel scaffold structure disclosed above can also be designed according to the field and/or situation in which the microchannel scaffold structure is to be applied, without special restrictions. For example, the thickness of the microchannel scaffold structure disclosed above can be about 2-6mm, such as about 2-5mm, about 3-6mm, 4-5mm, about 2mm, about 2.5mm, about 3mm, about 3.5mm, about 4mm, about 4.5mm, about 5mm, about 5.5mm, about 6mm, etc., but not limited thereto. In one embodiment, the microchannel scaffold structure disclosed above is applied to dentin regeneration, and the thickness of the microchannel scaffold structure can be about 4-5mm.

In one embodiment, the appearance of the microchannel support structure may be a cylinder, and the thickness of the cylinder may be about 2-6mm, such as about 2-5mm, about 3-6mm, about 3-5mm, about 2mm, about 2.5mm, about 3mm, about 3.5mm, about 4mm, about 4.5mm, about 5mm, about 5.5mm, about 6mm, etc., but not limited thereto. The diameter of the cylinder may be about 3-6mm, such as about 3-5mm, about 4-6mm, about 4-5mm, about 3mm, about 3.5mm, about 4mm, about 4.5mm, about 5mm, about 5.5mm, about 6mm, etc., but not limited thereto. In a specific embodiment, the appearance of the microchannel support structure may be a cylinder, and the thickness of the cylinder may be about 5mm, and the diameter of the cylinder may be about 5mm.

The microchannel support structure disclosed above can be composed of a composite material, but is not limited thereto. The composite material can include, but is not limited to, a biodegradable natural polymer material and a biodegradable ceramic material.

In the above composite material, the weight ratio of the biodegradable natural polymer material to the biodegradable ceramic material may be about 1:0.01-10, such as about 1:0.05-5, about 1:0.1-1, about 1:0.1, about 1:0.2, about 1:0.5, about 1:1, etc., but not limited thereto.

The above-mentioned biodegradable natural polymer material may include, but is not limited to, biodegradable unmodified natural polymers and/or biodegradable modified natural polymers. In one embodiment, the above-mentioned biodegradable natural polymer material may include, but is not limited to, natural collagen and/or modified collagen, natural gelatin and/or modified gelatin, natural hyaluronic acid and/or modified hyaluronic acid, natural chitosan and/or modified chitosan, natural alginate and/or modified alginate, etc., or any combination thereof. In a specific embodiment, the above-mentioned biodegradable natural polymer material may be collagen.

Furthermore, the above-mentioned biodegradable ceramic material may include, but is not limited to, hydroxyapatite, calcium sulfate, calcium carbonate, etc., or any combination thereof. In one embodiment, the above-mentioned biodegradable ceramic material may be hydroxyapatite.

In order to make the microchannel support structure disclosed in the present invention have the special structural design to prevent an undesired substance/cell from entering from a specific direction, the microchannel support structure disclosed in the present invention must be formed by a microchannel control system. In this microchannel control system, specific materials, solvents, homogenization methods, freeze-drying methods, etc. must be involved to obtain the above-mentioned microchannel support structure disclosed in the present invention.

That is, the microchannel support structure disclosed in the present invention needs to be formed by the method for preparing the microchannel support structure provided in the present invention as described below. The method for preparing the microchannel support structure provided in the present invention can simultaneously achieve the effects of microchannel formation, microchannel orientation, microchannel shaping and microchannel width control, but is not limited thereto.

The method for preparing the microchannel support structure disclosed above may include, but is not limited to, the following steps.

First, an alcohol solvent or an acidic solvent is added into a system and a cooling process is performed to make the temperature of the system lower than room temperature.

The alcohol solvent may include, but is not limited to, methanol, ethanol, isopropanol, etc., or any combination thereof. In one embodiment, the alcohol solvent is isopropanol. The acid solvent may include, but is not limited to, formic acid, acetic acid, propionic acid, hydrochloric acid, etc., or any combination thereof. In one embodiment, the acid solvent is acetic acid.

In one embodiment, an acidic solvent is added to the above system to cool it down. In a specific embodiment, acetic acid is added to the above system to cool it down.

Furthermore, in one embodiment, the above-mentioned cooling process is performed to reduce the temperature of the system to about 0-10°C, such as about 0°C, about 4°C, about 5°C, about 8°C, about 10°C, etc., but not limited thereto. In a specific embodiment, the above-mentioned cooling process is performed to reduce the temperature of the system to about 4°C.

After the cooling process, a biodegradable natural polymer material may be added to the system to form a mixed solution with the alcohol solvent or the acid solvent. The amount of the biodegradable natural polymer material added relative to the alcohol solvent or the acid solvent may be about 0.1-10% (w/v), such as 0.1-10% (w/v), such as about 0.5-8% (w/v), about 1-10% (w/v), about 0.1% (w/v), about 0.2% (w/v), about 0.25% (w/v), about 0.5% (w/v), about 1% (w/v), about 2% (w/v), about 2.5% (w/v), about 5% (w/v), about 8% (w/v), about 10% (w/v), etc., but not limited thereto. In one embodiment, the content of the above-mentioned biodegradable natural polymer material in the above-mentioned mixed solution may be about 1% (w/v).

In the method for preparing a microchannel stent structure disclosed herein, the above-mentioned biodegradable natural polymer material may include, but is not limited to, a biodegradable unmodified natural polymer and/or a biodegradable modified natural polymer. In one embodiment, the above-mentioned biodegradable natural polymer material may include, but is not limited to, natural collagen and/or modified collagen, natural gelatin and/or modified gelatin, natural hyaluronic acid and/or modified hyaluronic acid, natural chitosan and/or modified chitosan, natural alginate and/or modified alginate, etc., or any combination thereof. In a specific embodiment, the above-mentioned biodegradable natural polymer material may be collagen.

Next, in the system, the mixed solution is subjected to a static process. The time for executing the static process is not particularly limited, and can be determined according to the environmental parameters at the time of operation (such as the temperature, humidity, pressure, etc. of the system), the type, amount (content in the mixed solution) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, etc. In one embodiment, the time for executing the static process can be about 1 to 120 minutes, such as about 1 minute, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, about 30 minutes, about 40 minutes, about 45 minutes, about 60 minutes, about 90 minutes, about 100 minutes, about 120 minutes, etc., but is not limited thereto. In a specific embodiment, the time for executing the above-mentioned static process may be about 20 minutes.

After the above-mentioned static process, in the above-mentioned system, the above-mentioned mixed liquid is subjected to a first homogenization process to obtain a slurry.

The method used in the first homogenization process is not particularly limited, as long as the mixed liquid can be homogenized to obtain the slurry. The method used in the first homogenization process may also be determined based on the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixed liquid) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the state of the mixed liquid, etc. The first homogenization process can be performed at a speed of about 1,000 to 30,000 rpm, such as about 1,000 rpm, about 2,000 rpm, about 3,000 rpm, about 5,000 rpm, about 10,000 rpm, about 12,000 rpm, about 15,000 rpm, about 18,000 rpm, about 20,000 rpm, about 22,000 rpm, about 25,000 rpm, about 30,000 rpm, etc., but is not limited thereto. In one embodiment, the first homogenization process can be performed at a speed of about 22,000 rpm.

The time for executing the first homogenization process is not particularly limited, and may be determined according to the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the state of the mixed solution, etc. In one embodiment, the time for executing the first homogenization process may be about 1 to 180 minutes, such as about 1 minute, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, about 30 minutes, about 40 minutes, about 45 minutes, about 60 minutes, about 90 minutes, about 100 minutes, about 120 minutes, about 150 minutes, about 180 minutes, but not limited thereto. In a specific embodiment, the time for performing the first homogenization process may be about 90 minutes.

Then, after obtaining the above slurry, a biodegradable ceramic material is added to the above system to form a mixture with the above slurry. The amount of the above biodegradable ceramic material added relative to the above alcohol solvent or acidic solvent can be about 0.1-10% (w/v), such as about 0.5-8% (w/v), about 1-10% (w/v), about 0.1% (w/v), about 0.25% (w/v), about 0.5% (w/v), about 1% (w/v), about 2.5% (w/v), about 5% (w/v), about 8% (w/v), about 10% (w/v), etc., but not limited thereto. In one embodiment, the content of the above biodegradable ceramic material in the above mixture can be about 0.5% (w/v).

In the method for preparing the microchannel stent structure disclosed herein, the biodegradable ceramic material may include hydroxyapatite, calcium sulfate, calcium carbonate, etc., or any combination thereof, but is not limited thereto. In one embodiment, the biodegradable ceramic material may be hydroxyapatite.

Then, after the above mixture is formed, the above mixture is subjected to a second homogenization process in the above system to obtain a homogenate.

Similar to the first homogenization process, the method used in the second homogenization process is not particularly limited, as long as the mixture can be homogenized to obtain the homogenate. The method used in the second homogenization process can also be determined based on the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the type, amount (content in the mixture) and/or quality of the biodegradable ceramic material, the state of the mixture, etc. In one embodiment, the second homogenization process can be performed at a speed of about 1,000 to 30,000 rpm, such as about 1,000 rpm, about 2,000 rpm, about 3,000 rpm, about 5,000 rpm, about 10,000 rpm, about 12,000 rpm, about 15,000 rpm, about 18,000 rpm, about 20,000 rpm, about 22,000 rpm, about 25,000 rpm, about 30,000 rpm, etc., but not limited thereto. In a specific embodiment, the second homogenization process can be performed at a speed of about 22,000 rpm.

The time for executing the second homogenization process is not particularly limited and may be determined according to the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the type, amount (content in the mixture) and/or quality of the biodegradable ceramic material, the state of the mixture, the homogenization method to be adopted and/or the stirring speed, etc. In one embodiment, the time for executing the second homogenization process may be about 1 to 180 minutes, such as about 1 minute, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, about 30 minutes, about 40 minutes, about 45 minutes, about 60 minutes, about 90 minutes, about 100 minutes, about 120 minutes, about 150 minutes, about 180 minutes, but not limited thereto. In a specific embodiment, the time for executing the second homogenization process may be about 90 minutes.

After the second homogenization process, the homogenate is subjected to a centrifugation process in the system.

The centrifugal speed used in the above centrifugal procedure is not particularly limited and can be determined based on the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the operating environment), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the type, amount (content in the mixture) and/or quality of the biodegradable ceramic material, the state of the homogenate and/or the desired centrifugal time, etc. In one embodiment, the centrifugation process can be performed at about 100 to 5,000 rpm, such as about 100 rpm, about 200 rpm, about 500 rpm, about 600 rpm, about 800 rpm, about 1,000 rpm, about 1,200 rpm, about 1,500 rpm, about 1,800 rpm, about 2,000 rpm, about 3,000 rpm, about 5,000 rpm, etc., but not limited thereto. In a specific embodiment, the centrifugation process can be performed at a speed of about 2,000 rpm.

The time for performing the above-mentioned centrifugation procedure is not particularly limited, and can be determined according to the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the operating environment, etc.), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the type, amount (content in the mixture) and/or quality of the biodegradable ceramic material, the state of the homogenate and/or the centrifugation speed to be adopted, etc. In one embodiment, the time for performing the above-mentioned centrifugation procedure can be about 1 to 20 minutes, such as about 1 minute, about 2 minutes, about 3 minutes, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, etc., but is not limited thereto. In a specific embodiment, the time for performing the above-mentioned centrifugation process may be about 5 minutes.

Furthermore, after the centrifugation process, the homogenate is subjected to a freezing process. The method of subjecting the homogenate to the freezing process is not particularly limited and can be determined as needed. For example, the homogenate can be directly subjected to the freezing process, or the homogenate can be poured into a mold to undergo the freezing process. In one embodiment, the homogenate is poured into a mold to undergo the freezing process. The material forming the mold may include, but is not limited to, rubber material, plastic material, resin material, silicone material, etc. In one embodiment, the material forming the mold is silicone material.

The temperature used in the above freezing process is not particularly limited and can be determined based on the environmental parameters at the time of operation (such as humidity and pressure of the operating environment), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the type, amount (content in the mixture) and/or quality of the biodegradable ceramic material, the state of the homogeneous material and/or the desired freezing time, etc. In one embodiment, the temperature of the above freezing process may be about -80 to 0°C, such as about -80 to -20°C, about -70 to -20°C, about -50 to 0°C, about -80 to -70°C, about -80°C, about -70°C, about -60°C, about -50°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In a specific embodiment, the temperature of the above freezing process may be about -80 to -70°C.

There is no particular limit to the time for performing the above freezing process, which can be determined based on the environmental parameters at the time of operation (such as humidity and pressure of the operating environment), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the type, amount (content in the mixture) and/or quality of the biodegradable ceramic material, the state of the homogeneous material and/or the desired freezing temperature, etc. In one embodiment, the time for executing the above freezing procedure may be about 1 to 24 hours, such as about 2-21 hours, 3-18 hours, about 1 hour, about 2 hours, about 3 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In a specific embodiment, the time for executing the above freezing procedure may be about 12 hours.

Then, after the above-mentioned freezing process, the above-mentioned homogenate is subjected to a drying process to obtain the above-mentioned microchannel support structure disclosed in the present invention.

The above drying process may include, but is not limited to, the following steps:

(1) Cooling a drying plate to about -50 to 0°C, such as about -50 to -5°C, about -40 to -10°C, about -35 to -20°C, about -50°C, about -40°C, about -35°C, -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto;

(2) After cooling a drying plate to about -50 to 0°C, place the homogenate on the drying plate;

(3) After placing the homogenate on the drying plate, the homogenate is subjected to a first-stage microchannel support structure vacuum drying.

In the above-mentioned first stage of vacuum drying of the microchannel support structure, the temperature of the frozen plate can be about -50 to 0°C, such as about -50 to -5°C, about -40 to -10°C, about -35 to -20°C, about -50°C, about -40°C, about -35°C, -30°C, about -20°C, about -15°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the above-mentioned first stage of vacuum drying of the microchannel support structure, the temperature of the frozen plate can be about -35°C.

Furthermore, in the above-mentioned first stage of vacuum drying of the microchannel support structure, the condensation temperature may be about -90 to 0°C, such as about -90 to -5°C, -80 to -10°C, about -40 to -10°C, about -35 to -20°C, about -90 to -80°C, about -90°C, about -80°C, about -70°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the above-mentioned first stage of vacuum drying of the microchannel support structure, the condensation temperature may be about -90 to -80°C.

In the above-mentioned first stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 50Pa, such as about 1-40Pa, about 1-30Pa, about 1-20Pa, about 1-10Pa, about 1Pa, about 5Pa, about 10Pa, about 30Pa, about 50Pa, etc., but not limited thereto. In one embodiment, in the above-mentioned first stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 10Pa.

The time for performing the vacuum drying of the microchannel support structure in the first stage may be about 1-24 hours, such as about 1-21 hours, about 1-18 hours, about 1-15 hours, about 3-15 hours, about 5-12 hours, about 12 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In one embodiment, the time for performing the vacuum drying of the microchannel support structure in the first stage may be about 4 hours.

(4) After the first stage of vacuum drying of the microchannel support structure, the homogenate is subjected to a second stage of vacuum drying of the microchannel support structure.

In the above-mentioned second stage of vacuum drying of the microchannel support structure, the temperature of the shelf can be about -50 to 0°C, such as about -50 to -5°C, about -40 to -10°C, about -35 to -20°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -15°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the above-mentioned second stage of vacuum drying of the microchannel support structure, the temperature of the shelf can be about -15°C.

Furthermore, in the above-mentioned second stage of vacuum drying of the microchannel support structure, the condensation temperature may be about -90 to 0°C, such as about -90 to -5°C, -80 to -10°C, about -40 to -10°C, about -35 to -20°C, -90 to -80°C, about -90°C, about -80°C, about -70°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the above-mentioned second stage of vacuum drying of the microchannel support structure, the condensation temperature may be about -90 to -80°C.

In the above-mentioned second stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 50Pa, such as about 1-40Pa, about 1-30Pa, about 1-20Pa, about 1-10Pa, about 1Pa, about 5Pa, about 10Pa, about 30Pa, about 50Pa, etc., but not limited thereto. In one embodiment, in the above-mentioned second stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 10Pa.

The time for performing the vacuum drying of the microchannel support structure in the second stage may be about 1-24 hours, such as about 1-21 hours, about 1-18 hours, about 1-15 hours, about 3-15 hours, about 5-12 hours, about 12 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In one embodiment, the time for performing the vacuum drying of the microchannel support structure in the second stage may be about 3 hours.

(5) After the second stage of vacuum drying of the microchannel support structure, the homogenate is subjected to a third stage of vacuum drying of the microchannel support structure.

In the above-mentioned third stage of vacuum drying of the microchannel support structure, the temperature of the shelf can be about -50 to 0°C, such as about -50 to -5°C, about -40 to -10°C, about -35 to -20°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -15°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the above-mentioned third stage of vacuum drying of the microchannel support structure, the temperature of the shelf can be about 0°C.

Furthermore, in the above-mentioned third stage of vacuum drying of the microchannel support structure, the condensation temperature may be about -90 to 0°C, such as about -90 to -5°C, -80 to -10°C, about -40 to -10°C, about -35 to -20°C, -90 to -80°C, about -90°C, about -80°C, about -70°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the above-mentioned third stage of vacuum drying of the microchannel support structure, the condensation temperature may be about -90 to -80°C.

In the above-mentioned third stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 50Pa, such as about 1-40Pa, about 1-30Pa, about 1-20Pa, about 1-10Pa, about 1Pa, about 5Pa, about 10Pa, about 30Pa, about 50Pa, etc., but not limited thereto. In one embodiment, in the above-mentioned third stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 10Pa.

The time for performing the vacuum drying of the microchannel support structure in the third stage may be about 1-24 hours, such as about 1-21 hours, about 1-18 hours, about 1-15 hours, about 3-15 hours, about 5-12 hours, about 12 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In one embodiment, the time for performing the vacuum drying of the microchannel support structure in the third stage may be about 16 hours.

(6) After the third stage of vacuum drying of the microchannel support structure, the homogenate is subjected to a fourth stage of vacuum drying of the microchannel support structure.

In the above fourth stage of vacuum drying of the microchannel support structure, the temperature of the shelf can be about 0 to 50°C, such as about 5 to 50°C, about 10 to 45°C, about 15 to 40°C, about 20 to 35°C, about 0°C, about 5°C, about 10°C, about 15°C, about 20°C, about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, etc., but not limited thereto. In one embodiment, in the above fourth stage of freeze vacuum drying of the microchannel support structure, the temperature of the frozen shelf can be about 20°C.

Furthermore, in the fourth stage of vacuum drying of the microchannel support structure, the condensation temperature may be about -90 to 0°C, such as about -90 to -5°C, -80 to -10°C, about -40 to -10°C, about -35 to -20°C, -90 to -80°C, about -90°C, about -80°C, about -70°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the fourth stage of vacuum drying of the microchannel support structure, the condensation temperature may be about -90 to -80°C.

In the fourth stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 50 Pa, such as about 1-40 Pa, about 1-30 Pa, about 1-20 Pa, about 1-10 Pa, about 1 Pa, about 5 Pa, about 10 Pa, about 30 Pa, about 50 Pa, etc., but not limited thereto. In one embodiment, in the fourth stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 10 Pa.

The time for performing the vacuum drying of the microchannel support structure in the fourth stage may be about 1-24 hours, such as about 1-21 hours, about 1-18 hours, about 1-15 hours, about 3-15 hours, about 5-12 hours, about 12 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In one embodiment, the time for performing the vacuum drying of the microchannel support structure in the fourth stage may be about 4 hours.

In addition, the method for preparing the microchannel support structure disclosed herein, in addition to the above steps, may further include, after the above freeze-drying process, cutting the obtained microchannel support structure as needed to obtain the desired appearance shape and size.

In addition, the method for preparing the microchannel support structure disclosed herein may further include, in addition to the above steps, subjecting the microchannel support structure to a structural strengthening heating process after the above freeze drying process to strengthen the structural strength of the microchannel support structure.

The heating temperature of the above-mentioned structural strengthening heating process may be about 50 to 200°C, such as about 60-150°C, about 70-120°C, about 80-110°C, about 60°C, about 70°C, about 80°C, about 90°C, about 100°C, about 105°C, about 110°C, about 120°C, about 150°C, but not limited thereto. In one embodiment, the heating temperature of the above-mentioned structural strengthening heating process may be about 105°C.

The vacuum degree of the above-mentioned structure-enhanced heating process may be about 10 to 76 cmHg, for example, about 10 to 30 cmHg, about 40 to 60 cmHg, about 60 to 76 cmHg, about 10 cmHg, about 20 cmHg, about 50 cmHg, about 60 cmHg, about 76 cmHg, etc., but not limited thereto. In one embodiment, the vacuum degree of the above-mentioned structure-enhanced heating process may be about 60 to 76 cmHg.

Furthermore, the time for executing the above-mentioned structure strengthening heating procedure may be about 1-48 hours, such as about 6-48 hours, about 12-36 hours, about 18-24 hours, about 2 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 16 hours, about 24 hours, about 30 hours, about 36 hours, about 48 hours, but not limited thereto. In one embodiment, the time for executing the above-mentioned structure strengthening heating procedure may be about 24 hours.

In addition, the present disclosure can also provide a filling body, which may include a double-layer scaffold structure, and the double-layer scaffold structure has a special structural design, which can prevent an undesirable substance and/or cell from entering one layer into another layer, and can therefore be applied to situations where two types of tissues need to be repaired and/or reconstructed at the same time.

The filling body disclosed above can be applied to a tissue engineering and/or tissue regeneration-related application, but is not limited thereto. The above tissue engineering and/or tissue regeneration-related applications may include, but are not limited to, the reconstruction of soft tissue and/or hard tissue, for example, the reconstruction of dentin and dental pulp.

FIG. 2 shows a schematic diagram of a structure of a filling body disclosed in the present invention. See FIG. 2. The double-layer support structure in the filling body 2000 disclosed in the present invention may include any of the microchannel support structures 100 disclosed in the present invention and a porous support structure 200, but is not limited thereto. In the double-layer support structure in the filling body 2000 disclosed in the present invention, a bottom surface 100BS of the microchannel support structure 100 is bonded to a top surface 200TS of the porous support structure.

For the relevant description of the microchannel support structure in the filling body disclosed in the present invention, please refer to all the relevant descriptions of the microchannel support structure disclosed in the previous paragraph, so it will not be elaborated here.

The porous support structure 200 in the filling body 2000 disclosed in the present invention may have at least one hole 201. The size of the hole 201 is larger than the size of the opening 101BO of the microchannel in the microchannel support structure on the bottom surface 100BS of the microchannel support structure. The hole 201 may not have directionality relative to the microchannel 101 in the microchannel support structure 100 in the filling body 2000 disclosed in the present invention, and may be regular or irregular, without any special restrictions. In addition, the shapes and sizes of different holes may be the same or different, without any special restrictions.

The pore size of the porous scaffold structure may be about 10-200μm, such as about 20-150μm, about 30-120μm, about 40-100μm, about 50-90μm, about 10μm, about 20μm, about 30μm, about 40μm, about 50μm, about 60μm, about 70μm, about 80μm, about 100μm, about 120μm, about 130μm, about 150μm, about 170μm 180μm, about 200μm, etc., but not limited thereto.

By the design of bonding a bottom surface of the microchannel support structure and a top surface of the porous support structure, substances and/or cells that exist in the porous support structure but are not expected to enter the microchannel support structure cannot enter the microchannel support structure. In other words, by the design of the filler disclosed in the present invention, when the filler disclosed in the present invention is used to simultaneously reconstruct different tissues, the growth of the two tissues will not interfere with each other.

In one embodiment, the pores of the porous scaffold structure have a pore size larger than the size of a cell to allow a cell to enter the porous scaffold structure and grow therein. The cells described herein may include undifferentiated cells, fibroblasts, immune cells, etc., or any combination thereof, but are not limited thereto. In a specific embodiment, the cells described herein may include cells contained in dental pulp tissue, such as undifferentiated cells, fibroblasts, immune cells, etc., or any combination thereof.

In a specific embodiment, the filler disclosed herein can be applied to a tooth repair to simultaneously reconstruct the dentin and pulp tissue, wherein the microchannel scaffold structure disclosed herein in the filler disclosed herein is applicable to the reconstruction of the dentin, and the porous scaffold structure disclosed herein is applicable to the reconstruction of the pulp. Due to the design of the filler disclosed herein, when the filler disclosed herein is applied to the tooth repair, the cells of the pulp tissue that grow faster in the porous scaffold structure in the filler disclosed herein will not enter the microchannel scaffold structure in the filler disclosed herein and affect the growth of the dentin tissue in the microchannel scaffold structure.

In addition, the appearance shape of the porous scaffold structure in the filler disclosed above can also be designed according to the field and/or situation in which the porous scaffold structure in the filler disclosed above is intended to be used, without special restrictions. Examples of the appearance shape of the porous scaffold structure may include, but are not limited to, layers, columns, pyramids, blocks, etc. In addition, the above-mentioned columns may include, but are not limited to, cylinders, triangular prisms, square prisms, polygonal prisms, etc. The above-mentioned pyramids may include, but are not limited to, cones, triangular pyramids, tetrahedral pyramids, polygonal pyramids, etc. In one embodiment, the porous scaffold structure in the filler disclosed above is used for dental pulp regeneration, and the appearance shape of the microchannel scaffold structure is a cylinder.

Similarly, the appearance size of the porous support structure in the filler disclosed above can also be designed according to the field and/or situation in which the porous support structure in the filler disclosed above is intended to be applied, without special restrictions. In addition, the appearance size of the porous support structure in the filler disclosed above and the appearance shape of the porous support structure in the filler disclosed above can be designed based on each other, but are not limited to this.

The thickness of the porous scaffold structure in the filler disclosed above can also be designed according to the field and/or situation in which the porous scaffold structure in the filler disclosed above is intended to be applied, without special restrictions. For example, the thickness of the porous scaffold structure in the filler disclosed above can be about 1-5mm, such as about 1-4mm, about 2-4mm, about 1mm, about 1.5mm, about 2mm, about 2.5mm, about 3mm, about 3.5mm, about 4mm, about 4.5mm, about 5mm, etc., but not limited thereto. In one embodiment, the porous scaffold structure in the filler disclosed above is applied to dental pulp regeneration, and the thickness of the porous scaffold structure can be about 2-4mm.

In one embodiment, the porous support structure may be in the shape of a cylinder, and the thickness of the cylinder may be about 1-5 mm, such as about 1-4 mm, about 2-4 mm, about 1 mm, about 1.5 mm, about 2 mm, about 2.5 mm, about 3 mm, about 3.5 mm, about 4 mm, about 4.5 mm, about 5 mm, etc., and the diameter of the cylinder may be about 3-6 mm, such as about 3-5 mm, about 4-6 mm, about 4-5 mm, about 3 mm, about 3.5 mm, about 4 mm, about 4.5 mm, about 5 mm, about 5.5 mm, about 6 mm, etc. In a specific embodiment, the porous support structure may be in the shape of a cylinder, and the thickness of the cylinder may be about 2-4 mm, and the diameter of the cylinder may be about 4-5 mm.

Similarly, the overall appearance and size of the filler disclosed above can also be designed according to the field and/or situation of its intended application, without special restrictions. Examples of the appearance shape of the filler may include, but are not limited to, layers, columns, pyramids, blocks, etc. In addition, the above-mentioned columns may include, but are not limited to, cylinders, triangular prisms, square prisms, polygonal prisms, etc. The above-mentioned pyramids may include, but are not limited to, cones, triangular pyramids, tetrahedral pyramids, polygonal pyramids, etc.

In one embodiment, the overall appearance of the filler may be a cylinder, that is, both the microchannel support structure and the porous support structure in the filler disclosed herein are cylinders. In this embodiment, the thickness of the cylinder of the microchannel support structure may be about 2-6 mm, and the diameter may be about 3-6 mm, while the thickness of the cylinder of the porous support structure may be about 1-5 mm, and the diameter may be about 3-6 mm, but not limited thereto.

The porous scaffold structure in the filler disclosed above may be composed of a single type of material, but is not limited to this. The single type of material may include, but is not limited to, a biodegradable natural polymer material.

The above-mentioned biodegradable natural polymer material may include, but is not limited to, biodegradable unmodified natural polymers and/or biodegradable modified natural polymers. In one embodiment, the above-mentioned biodegradable natural polymer material may include, but is not limited to, natural collagen and/or modified collagen, natural gelatin and/or modified gelatin, natural hyaluronic acid and/or modified hyaluronic acid, natural chitosan and/or modified chitosan, natural alginate and/or modified alginate, etc., or any combination thereof. In a specific embodiment, the above-mentioned biodegradable natural polymer material may be collagen.

In the filler disclosed herein, the biodegradable natural polymer material in the composite material used to form the microchannel support structure and the biodegradable natural polymer material used to form the porous support structure can be independent of each other, that is, the two can be the same or different. In one embodiment, the biodegradable natural polymer material in the composite material used to form the microchannel support structure and the biodegradable natural polymer material used to form the porous support structure are both collagen.

In order to make the filling body disclosed in the present invention maintain the respective functions and characteristics of the above-mentioned microchannel support structure and porous support structure at the same time, and make the two closely bonded without adhesive, the filling body disclosed in the present invention must be formed by a microchannel controlled shaping system. In this microchannel controlled shaping system, specific materials, solvents, homogenization methods, freeze drying methods, bonding methods, etc. must be involved in it to obtain the above-mentioned filling body disclosed in the present invention.

In other words, the microchannel controlled shaping system disclosed in the present invention needs to be formed by the method for preparing the filling body provided in the present invention as described below. The method for preparing the filling body provided in the present invention can simultaneously achieve the effects of forming the microchannel of the microchannel support structure, orienting the microchannel, shaping the microchannel and controlling the width of the microchannel, forming the holes of the porous support structure, shaping the filling body, etc., but is not limited to this.

The method for preparing a filling body provided in the present disclosure may include, but is not limited to, the following steps.

(A) preparing a microchannel support structure; (B) preparing an uncured body of a porous support structure; (C) directly contacting the bottom surface of the microchannel support structure with the uncured body of the porous support structure to form a double-layer stack; and (D) subjecting the double-layer stack to a freeze-drying process to form the filling body.

For the relevant description of step (A) of preparing a microchannel support structure, please refer to all the relevant descriptions of the method for preparing a microchannel support structure disclosed in the previous paragraph, so it will not be elaborated here.

It should be noted that the preparation of a microchannel support structure in step (A) and the preparation of an uncured body of a porous support structure in step (B) can be independent of each other, that is, all the detailed steps and parameters in the preparation of an uncured body of a porous support structure in step (B) may not be affected by all the detailed steps and parameters in the preparation of a microchannel support structure in step (A), or may be adjusted according to all the detailed steps and parameters in the preparation of a microchannel support structure in step (A).

The step (B) of preparing an uncured body of a porous scaffold structure may include the following steps, but is not limited thereto.

First, an alcohol solvent or an acidic solvent is added into a system and a cooling process is performed to make the temperature of the system lower than room temperature.

The alcohol solvent may include, but is not limited to, methanol, ethanol, isopropanol, etc., or any combination thereof. In one embodiment, the alcohol solvent is isopropanol. The acid solvent may include, but is not limited to, formic acid, acetic acid, propionic acid, hydrochloric acid, etc., or any combination thereof. In one embodiment, the acid solvent is acetic acid.

In one embodiment, an alcohol solvent is added to the above system to cool it down. In a specific embodiment, isopropanol is added to the above system to cool it down.

The alcohol solvent or acidic solvent used in the above step of preparing a microchannel support structure and the alcohol solvent or acidic solvent used in the above step of preparing an uncured body of a porous support structure can be independent of each other, that is, the two can be the same or different. In one embodiment, the solvent used for the biodegradable natural polymer material used in the above step of preparing a microchannel support structure is acetic acid, and the alcohol solvent or acidic solvent used in the above step of preparing an uncured body of a porous support structure is isopropanol.

Furthermore, in one embodiment, the above-mentioned cooling process is performed to reduce the temperature of the system to about 0-10°C, such as about 0°C, about 4°C, about 5°C, about 8°C, about 10°C, etc., but not limited thereto. In a specific embodiment, the above-mentioned cooling process is performed to reduce the temperature of the system to about 4°C.

Then, after the cooling process, a biodegradable natural polymer material may be added to the system to form a mixed solution with the alcohol solvent or the acid solvent. The amount of the biodegradable natural polymer material added relative to the alcohol solvent or the acid solvent may be about 0.1-10% (w/v), such as about 0.5-8% (w/v), about 1-10% (w/v), about 0.1% (w/v), about 0.2% (w/v), about 0.25% (w/v), about 0.5% (w/v), about 1% (w/v), about 2% (w/v), about 2.5% (w/v), about 5% (w/v), about 8% (w/v), about 10% (w/v), etc., but not limited thereto. In one embodiment, the content of the above-mentioned biodegradable natural polymer material in the above-mentioned mixed solution may be about 2% (w/v).

In the step of preparing an uncured body of a porous scaffold structure, the biodegradable natural polymer material may include, but is not limited to, a biodegradable unmodified natural polymer and/or a biodegradable modified natural polymer. In one embodiment, the biodegradable natural polymer material may include, but is not limited to, natural collagen and/or modified collagen, natural gelatin and/or modified gelatin, natural hyaluronic acid and/or modified hyaluronic acid, natural chitosan and/or modified chitosan, natural alginate and/or modified alginate, etc., or any combination thereof. In a specific embodiment, the biodegradable natural polymer material may be collagen.

The biodegradable natural polymer material used in the step of preparing a microchannel scaffold structure and the biodegradable natural polymer material used in the step of preparing an uncured body of a porous scaffold structure can be independent of each other, that is, the two can be the same or different. In one embodiment, the biodegradable natural polymer material used in the step of preparing a microchannel scaffold structure and the biodegradable natural polymer material used in the step of preparing an uncured body of a porous scaffold structure are both collagen.

Then, in the above system, the above mixed solution is subjected to a static process. The time for executing the above static process is not particularly limited, and can be determined according to the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, etc. In one embodiment, the time for executing the above static process can be about 1 to 120 minutes, such as about 1 minute, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, about 30 minutes, about 40 minutes, about 45 minutes, about 60 minutes, about 90 minutes, about 100 minutes, about 120 minutes, etc., but not limited thereto. In a specific embodiment, the time for executing the above-mentioned static process may be about 20 minutes.

After the above-mentioned static process, the above-mentioned mixed liquid is subjected to a homogenization process in the above-mentioned system to obtain a slurry.

The method used in the above homogenization process is not particularly limited, as long as the above mixed liquid can be homogenized to obtain the above slurry. The method used in the above homogenization process can also be determined according to the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixed liquid) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the state of the mixed liquid and/or the desired homogenization time, etc. The above homogenization process can be performed at a speed of about 1,000 to 30,000 rpm, such as about 1,000 rpm, about 2,000 rpm, about 3,000 rpm, about 5,000 rpm, about 10,000 rpm, about 12,000 rpm, about 15,000 rpm, about 18,000 rpm, about 20,000 rpm, about 22,000 rpm, about 25,000 rpm, about 30,000 rpm, etc., but is not limited thereto. In one embodiment, the above homogenization process can be performed at a speed of about 18,000 rpm.

There is no particular limitation on the time for performing the above homogenization process, and the time may be determined according to the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixture) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the state of the mixed solution, the homogenization method to be adopted and/or the stirring speed, etc. In one embodiment, the time for performing the above homogenization process may be about 1 to 180 minutes, such as about 1 minute, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, about 30 minutes, about 40 minutes, about 45 minutes, about 60 minutes, about 90 minutes, about 100 minutes, about 120 minutes, about 150 minutes, about 180 minutes, but not limited thereto. In a specific embodiment, the time for performing the above first homogenization process may be about 30 minutes.

Then, after the homogenization process, the slurry is subjected to a centrifugation process in the system to obtain an uncured body of the porous scaffold structure.

The centrifugal speed used in the above-mentioned centrifugal process is not particularly limited, and can be determined according to the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixed solution) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the state of the slurry, etc. In one embodiment, the above-mentioned centrifugal process can be performed at a speed of about 100 to 5,000 rpm, such as about 100 rpm, about 200 rpm, about 500 rpm, about 600 rpm, about 800 rpm, about 1,000 rpm, about 1,200 rpm, about 1,500 rpm, about 1,800 rpm, about 2,000 rpm, about 3,000 rpm, about 5,000 rpm, etc., but is not limited thereto. In a specific embodiment, the above centrifugation process can be performed at a rotation speed of about 2,000 rpm.

There is no particular limitation on the time for performing the above centrifugation procedure, and it can be determined according to the environmental parameters at the time of operation (such as the temperature, humidity and/or pressure of the system, etc.), the type, amount (content in the mixed solution) and/or quality of the biodegradable natural polymer material, the type, concentration, amount and/or quality of the solvent, the state of the slurry, etc. In one embodiment, the time for performing the above centrifugation procedure can be about 1 to 20 minutes, such as about 1 minute, about 2 minutes, about 3 minutes, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, etc., but not limited thereto. In a specific embodiment, the time for performing the above centrifugation procedure can be about 5 minutes.

There is no special limitation on the method of directly contacting the bottom surface of the microchannel support structure with the uncured body of the porous support structure in the above step (C), as long as the bottom surface of the microchannel support structure can directly contact the uncured body of the porous support structure without affecting or contacting other surfaces of the microchannel support structure. For example, the uncured body of the porous support structure can be injected into a mold first, and then the bottom surface of the microchannel support structure can be directly contacted with the uncured body of the porous support structure in the mold, but it is not limited to this. The forming material of the above mold can include stainless steel, aluminum alloy, titanium alloy, etc., but it is not limited to this.

The above-mentioned step (D) of subjecting the above-mentioned double-layer stacking to a freeze-drying process to form the above-mentioned filling body disclosed herein may include, but is not limited to, the following steps.

(1) Cooling a freeze-drying plate to about -50 to 0°C, such as about -50 to -5°C, about -40 to -10°C, about -35 to -20°C, about -50°C, about -40°C, about -35°C, -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto.

(2) After cooling a freeze-drying plate to about -50 to 0°C, place the double-layer stack on the freeze-drying plate.

(3) After cooling the temperature of a freeze drying plate to about -50 to 0°C, the double-layer stack is subjected to a quiescent process. There is no particular restriction on the time for executing the quiescent process for the double-layer stack, which can be determined according to the environmental parameters (such as system temperature, humidity and/or pressure, etc.) and the state of the double-layer stack at the time of operation. In one embodiment, the time for executing the above-mentioned static process for double-layer stacking can be about 0.5 to 24 hours, such as about 1 to 21 hours, about 0.5 hours, about 1 hour, about 2 hours, about 2.5 hours, about 3 hours, about 5 hours, about 6 hours, about 8 hours, about 12 hours, about 16 hours, about 18 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In a specific embodiment, the time for executing the above-mentioned static process for double-layer stacking can be about 3 hours.

(4) After the double-layer stack is subjected to a static process, the double-layer stack is subjected to a first-stage filling body vacuum drying.

In the first stage of vacuum drying of the filling body, the temperature of the shelf can be about -50 to 0°C, such as about -50 to -5°C, about -40 to -10°C, about -35 to -20°C, about -50°C, about -40°C, about -35°C, -30°C, about -20°C, about -15°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the first stage of vacuum drying of the filling body, the temperature of the frozen shelf can be about -35°C.

Furthermore, in the first stage of vacuum drying of the filler, the condensation temperature may be about -90 to 0°C, such as about -90 to -5°C, -80 to -10°C, about -40 to -10°C, about -35 to -20°C, about -90 to -80°C, about -90°C, about -80°C, about -70°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the first stage of vacuum drying of the filler, the condensation temperature may be about -90 to -80°C.

In the first stage of vacuum drying of the filling body, the vacuum degree may be about 1 to 50 Pa, such as about 1-40 Pa, about 1-30 Pa, about 1-20 Pa, about 1-10 Pa, about 1 Pa, about 5 Pa, about 10 Pa, about 30 Pa, about 50 Pa, etc., but not limited thereto. In one embodiment, in the first stage of vacuum drying of the filling body, the vacuum degree may be about 1 to 10 Pa.

The time for performing the first stage of vacuum drying of the filling body may be about 1-24 hours, such as about 1-21 hours, about 1-18 hours, about 1-15 hours, about 3-15 hours, about 5-12 hours, about 12 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In one embodiment, the time for performing the first stage of vacuum drying of the filling body may be about 4 hours.

(5) After the first stage of vacuum drying of the filling body, the double-layer stack is subjected to a second stage of vacuum drying of the filling body.

In the second stage of vacuum drying of the filling body, the temperature of the shelf may be about -50 to 0°C, such as about -50 to -5°C, about -40 to -10°C, about -35 to -20°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -15°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the second stage of vacuum drying of the filling body, the temperature of the shelf may be about -15°C.

Furthermore, in the above-mentioned second stage of vacuum drying of the filling body, the condensation temperature may be about -90 to 0°C, such as about -90 to -5°C, -80 to -10°C, about -40 to -10°C, about -35 to -20°C, -90 to -80°C, about -90°C, about -80°C, about -70°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the above-mentioned second stage of vacuum drying of the filling body, the condensation temperature may be about -90 to -80°C.

In the above-mentioned second stage of vacuum drying of the filling body, the vacuum degree may be about 1 to 50Pa, such as about 1-40Pa, about 1-30Pa, about 1-20Pa, about 1-10Pa, about 1Pa, about 5Pa, about 10Pa, about 30Pa, about 50Pa, etc., but not limited thereto. In one embodiment, in the above-mentioned second stage of vacuum drying of the filling body, the vacuum degree may be about 1 to 10Pa.

The time for performing the second stage of vacuum drying of the filling body may be about 1-24 hours, such as about 1-21 hours, about 1-18 hours, about 1-15 hours, about 3-15 hours, about 5-12 hours, about 12 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In one embodiment, the time for performing the second stage of vacuum drying of the filling body may be about 3 hours.

(6) After the second stage of vacuum drying of the filling body, the double-layer stacking is subjected to a third stage of vacuum drying of the filling body.

In the third stage of vacuum drying of the filling body, the temperature of the shelf can be about -50 to 0°C, such as about -50 to -5°C, about -40 to -10°C, about -35 to -20°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -15°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the third stage of vacuum drying of the filling body, the temperature of the shelf can be about 0°C.

Furthermore, in the third stage of vacuum drying of the filling body, the condensation temperature may be about -90 to 0°C, such as about -90 to -5°C, -80 to -10°C, about -40 to -10°C, about -35 to -20°C, -90 to -80°C, about -90°C, about -80°C, about -70°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the third stage of vacuum drying of the filling body, the condensation temperature may be about -90 to -80°C.

In the third stage of vacuum drying of the filling body, the vacuum degree may be about 1 to 50 Pa, such as about 1-40 Pa, about 1-30 Pa, about 1-20 Pa, about 1-10 Pa, about 1 Pa, about 5 Pa, about 10 Pa, about 30 Pa, about 50 Pa, etc., but not limited thereto. In one embodiment, in the third stage of vacuum drying of the microchannel support structure, the vacuum degree may be about 1 to 10 Pa.

The time for performing the third stage of vacuum drying of the filling body may be about 1-24 hours, such as about 1-21 hours, about 1-18 hours, about 1-15 hours, about 3-15 hours, about 5-12 hours, about 12 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In one embodiment, the time for performing the third stage of vacuum drying of the filling body may be about 16 hours.

(7) After the third stage of vacuum drying of the filling body, the double-layer stacking is subjected to a fourth stage of vacuum drying of the filling body.

In the fourth stage of vacuum drying of the filling body, the temperature of the shelf may be about 0 to 50°C, such as about 5 to 50°C, about 10 to 45°C, about 15 to 40°C, about 20 to 35°C, about 0°C, about 5°C, about 10°C, about 15°C, about 20°C, about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, but not limited thereto. In one embodiment, in the fourth stage of vacuum drying of the filling body, the temperature of the shelf may be about 20°C.

Furthermore, in the fourth stage of vacuum drying of the filling body, the condensation temperature may be about -90 to 0°C, such as about -90 to -5°C, -80 to -10°C, about -40 to -10°C, about -35 to -20°C, -90 to -80°C, about -90°C, about -80°C, about -70°C, about -50°C, about -40°C, about -35°C, about -30°C, about -20°C, about -10°C, about 0°C, etc., but not limited thereto. In one embodiment, in the fourth stage of vacuum drying of the filling body, the condensation temperature may be about -90 to -80°C.

In the fourth stage of vacuum drying of the filling body, the vacuum degree may be about 1 to 50 Pa, such as about 1-40 Pa, about 1-30 Pa, about 1-20 Pa, about 1-10 Pa, about 1 Pa, about 5 Pa, about 10 Pa, about 30 Pa, about 50 Pa, etc., but not limited thereto. In one embodiment, in the fourth stage of vacuum drying of the filling body, the vacuum degree may be about 1 to 10 Pa.

The time for performing the fourth stage of vacuum drying of the filling body may be about 1-24 hours, such as about 1-21 hours, about 1-18 hours, about 1-15 hours, about 3-15 hours, about 5-12 hours, about 12 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 15 hours, about 16 hours, about 18 hours, about 20 hours, about 21 hours, about 24 hours, etc., but not limited thereto. In one embodiment, the time for performing the fourth stage of vacuum drying of the filling body may be about 4 hours.

Furthermore, the method for preparing the filling body disclosed above may further include, after the above freeze-drying process, cutting the obtained filling body as needed to obtain the desired appearance shape and size.

In addition, the method for preparing the filling body disclosed herein may further include, after the above-mentioned freeze-drying process, subjecting the above-mentioned filling body to a structural strengthening heating process to strengthen the structural strength of the filling body.

The heating temperature of the above-mentioned structural strengthening heating process may be about 50 to 200°C, such as about 60-150°C, about 70-120°C, about 80-110°C, about 60°C, about 70°C, about 80°C, about 90°C, about 100°C, about 105°C, about 110°C, about 120°C, about 150°C, but not limited thereto. In one embodiment, the heating temperature of the above-mentioned structural strengthening heating process may be about 105°C.

The vacuum degree of the above-mentioned structure-enhancing heating process may be about 10 to 76 cmHg, for example, about 10 to 30 cmHg, about 40 to 60 cmHg, about 60 to 76 cmHg, about 10 cmHg, about 20 cmHg, about 50 cmHg, about 60 cmHg, about 76 cmHg, etc., but not limited thereto. In one embodiment, the vacuum degree of the above-mentioned structure-enhancing heating process may be about 60 to 76 cmHg.

Furthermore, the time for executing the above-mentioned structure strengthening heating procedure may be about 1-48 hours, such as about 6-48 hours, about 12-36 hours, about 18-24 hours, about 2 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 8 hours, about 10 hours, about 12 hours, about 16 hours, about 24 hours, about 30 hours, about 36 hours, about 48 hours, but not limited thereto. In one embodiment, the time for executing the above-mentioned structure strengthening heating procedure may be about 24 hours.

Implementation example

Preparation of the filling body disclosed herein

A. Preparation of microchannel support structure

The microchannel support structure was prepared according to the following method.

(1) Add 400 mL of acetic acid solvent (concentration 0.05 M) into a homogenizing device;

(2) Cool the above homogenizing equipment to 4°C;

(3) Add 4.0g of collagen into the above homogenizing device to form a mixed solution with acetic acid solvent;

(4) Place the above mixed solution in the above homogenizing equipment for 20 minutes;

(5) Homogenize the above mixed solution at a speed of 22,000 rpm for 90 minutes to form a slurry;

(6) Add 2.0 g of hydroxyapatite to the above homogenizing device to form a mixture with the above slurry;

(7) Homogenize the slurry at a speed of 22,000 rpm for 90 minutes to form a homogenous body;

(8) Centrifuge the above homogenate at a speed of 2000 rpm;

(9) Inject the centrifuged homogenate into a silicone mold;

(10) Place the silicone mold containing the above homogenate in a freezing device at -80 to -70°C for more than 12 hours;

(11) After cooling down, place the silicone mold containing the above homogenate on the drying equipment shelf (the shelf has been cooled to -35°C);

(12) Carry out the first stage of vacuum drying. Shelf temperature: -35°C, condensation temperature: -90 to -80°C, vacuum degree: 1 to 10pa, vacuum drying time: 4 hours;

(13) After the first stage of vacuum drying, the second stage of vacuum drying is carried out. Shelf temperature: -15°C, condensation temperature: -90 to -80°C, vacuum degree: 1 to 10pa, vacuum drying time: 3 hours;

(14) After the second stage of vacuum drying, the third stage of vacuum drying is carried out. Shelf temperature: 0°C, condensation temperature: -90 to -80°C, vacuum degree: 1 to 10pa, vacuum drying time: at least 16 hours;

(15) After the third stage of vacuum drying, the fourth stage of vacuum drying is performed to obtain a microchannel support structure. Shelf temperature: 20°C, condensation temperature: -90 to -80°C, vacuum degree: 1 to 10 Pa, vacuum drying time: 4 hours;

(16) After the fourth stage of vacuum drying, the microchannel support structure is subjected to a structural strengthening heating procedure. Heating temperature: 105°C, vacuum degree: 60~76cmHg, execution time: 24 hours.

(17) A reinforced microchannel support structure is obtained.

The reinforced microchannel support structure was subjected to scanning electron microscopy (SEM) analysis, and the results are shown in Figures 3A and 3B.

Figure 3A shows a 40X scanning electron microscope image of the microchannel support structure, where the dashed arrow shows the directionality of the microchannel. Figure 3B shows a 100X scanning electron microscope image of the microchannel support structure, where the dashed box shows the position of the microchannel and the dashed arrow shows the width of the microchannel.

According to Figures 3A and 3B, the above disclosed method for preparing a microchannel support can indeed generate a directional microchannel in the microchannel support structure, in which the width of the microchannel decreases toward a specific direction (such as the bottom surface of the microchannel support structure) and extends toward the specific direction.

B. Preparation of filling body

The filling body disclosed herein is prepared according to the following method.

(1) Add 300 mL of isopropyl alcohol solvent (concentration 10%) into a homogenizing device;

(2) Cool the above homogenizing equipment to 4°C;

(3) Add 6.0g of collagen into the above homogenizing device to form a mixed solution with isopropyl alcohol solvent;

(4) Place the above mixed solution in the above homogenizing equipment for 20 minutes;

(5) Homogenize the mixed solution at 18,000 rpm for 30 minutes to form a slurry;

(6) Centrifuge the above slurry at 2,000 rpm for 5 minutes;

(7) Inject the centrifuged slurry into a stainless steel mold;

(8) The bottom surface of the microchannel support structure prepared above is directly contacted with the slurry in the stainless steel mold to form a double-layer stack;

(9) The above-mentioned stainless steel mold is placed on the shelf of the freeze drying equipment (the shelf has been cooled to -35℃);

(10) Leave it alone for 3 hours;

(11) Carry out the first stage of vacuum drying. Shelf temperature: -35°C, condensation temperature: -90 to -80°C, vacuum degree: 1 to 10pa, vacuum drying time: 4 hours;

(12) After the first stage of vacuum drying, the second stage of vacuum drying is carried out. Shelf temperature: -15°C, condensation temperature: -90 to -80°C, vacuum degree: 1 to 10pa, vacuum drying time: 3 hours;

(13) After the second stage of vacuum drying, the third stage of vacuum drying is carried out. Shelf temperature: 0°C, condensation temperature: -90 to -80°C, vacuum degree: 1 to 10pa, vacuum drying time: at least 16 hours;

(14) After the third stage of vacuum drying, the fourth stage of vacuum drying is carried out to obtain the filling body. Shelf temperature: 20°C, condensation temperature: -90 to -80°C, vacuum degree: 1 to 10pa, vacuum drying time: 4 hours;

(15) After the fourth stage of vacuum drying, the obtained filling body is subjected to a structural strengthening heating procedure. Heating temperature: 105°C, vacuum degree: 60~76cmHg, execution time: 24 hours.

(16) A reinforced filling body is obtained.

Then, the reinforced filling body was subjected to micro computed tomography (Micro-CT) analysis, and the results are shown in Figure 4.

According to FIG. 4, the filling body 400 obtained by the method for preparing the filling body disclosed above does have two layers of microchannel support structure 401 and porous support structure 403 with different appearances, and the appearance of the porous support structure 403 has obvious holes.

Although the present invention has been disclosed as above with the preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined in the attached patent application.

100: Microchannel support structure

100BS: Bottom surface of microchannel support structure

101: Microchannel

101W: Width of microchannel

101BO: The opening of microchannel 101 on the bottom surface 100BS of the microchannel support structure

Claims (6)

A method for preparing a filling body, comprising: (A) preparing a microchannel support structure; (B) preparing an uncured body of a porous support structure; and (C) directly contacting the bottom surface of the microchannel support structure with the uncured body of the porous support structure to form a double-layer stack; (D) subjecting the double-layer stack to a freeze-drying process to form the filling body; wherein step (A) comprises: (A-1) placing a first (A-2) after the first cooling process, adding a first biodegradable natural polymer material to the first alcohol solvent or the acidic solvent to form a mixed solution, wherein the amount of the first biodegradable natural polymer material added relative to the first alcohol solvent or the acidic solvent is about 0.1-10% (w/v) ); (A-3) subjecting the first mixed solution to a first static process; (A-4) subjecting the first mixed solution to a first homogenization process after the first static process to obtain a first slurry; (A-5) adding a biodegradable ceramic material to the first slurry to form a mixture, wherein the amount of the biodegradable ceramic material added is about 0.1-10% (w/v) relative to the first alcohol solvent or acidic solvent; (A-6) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-7) adding a biodegradable ceramic material to the first alcohol solvent or acidic solvent; (A-8) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-9) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-10) adding a biodegradable ceramic material to the first alcohol solvent or acidic solvent; (A-11) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-12) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-13) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-14) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-15) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-16) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-17) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-18) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-19) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-20) adding a biodegradable ceramic material to the first slurry to form a mixture; (A-21) adding a biodegradable ceramic material to -6) subjecting the mixture to a second homogenization process to obtain a homogenate; (A-7) subjecting the homogenate to a first centrifugation process; (A-8) subjecting the homogenate to a freezing process after the first centrifugation process; and (A-9) subjecting the homogenate to a microchannel support structure drying process after the freezing process to obtain the microchannel support structure; wherein the microchannel support structure drying process includes: (A-9- 1) cooling a first drying plate to a temperature of about -50 to 0°C; (A-9-2) placing the homogenate on the drying plate after cooling the drying plate to a temperature of about -50 to 0°C; (A-9-3) performing a first stage microchannel support structure vacuum drying on the homogenate after placing the homogenate on the first drying plate, wherein the plate temperature during the first stage microchannel support structure vacuum drying is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the time for performing the first stage of vacuum drying of the microchannel support structure is about 1-24 hours; (A-9-4) after the first stage of vacuum drying of the microchannel support structure, the homogeneous material is subjected to a second stage of vacuum drying of the microchannel support structure, wherein in the second stage of vacuum drying of the microchannel support structure, the temperature of the shelf is about - 50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 pa, and the execution time is about 1-24 hours; (A-9-5) after the second stage of vacuum drying of the microchannel support structure, the homogeneous material is subjected to a third stage of vacuum drying of the microchannel support structure, wherein in the third stage of vacuum drying of the microchannel support structure, the temperature of the shelf is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 pa, and the execution time is about 1-24 hours. The vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours; and (A-9-6) after the third stage of vacuum drying of the microchannel support structure, the homogenate is subjected to a fourth stage of vacuum drying of the microchannel support structure, wherein in the fourth stage of vacuum drying of the microchannel support structure, the temperature of the shelf is about 0 to 50° C., the condensation temperature is about -90 to 0° C., the vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours; wherein step (B) includes: (B-1) subjecting a second alcohol solvent or an acidic solvent to a second cooling process to make the temperature of the second alcohol solvent or the acidic solvent lower than room temperature; (B-2) after the second cooling process, adding a second biodegradable natural polymer material to the second alcohol solvent or the acidic solvent to form a second mixed solution, wherein the second biodegradable natural polymer material The amount of the second alcohol solvent or the acidic solvent added is about 0.1-10% (w/v); (B-3) subjecting the second mixed solution to a second static process; (B-4) subjecting the second mixed solution to a third homogenization process after the second static process to obtain a slurry; and (B-5) subjecting the slurry to a second centrifugation process to form an uncured body of the porous scaffold structure; wherein step (D) comprises: ( D-1) cooling a second freeze-drying plate to a temperature of about -50 to 0°C; (D-2) placing the double-layer stack on the freeze-drying plate after cooling the second freeze-drying plate to a temperature of about -50 to 0°C; (D-3) performing a third static process on the double-layer stack after stacking the double-layer stack on the second freeze-drying plate; (D-4) performing a third static process on the double-layer stack after the third static process a first stage of vacuum drying of the filling body, wherein in the first stage of vacuum drying of the filling body, the plate temperature is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the time for performing the first stage of vacuum drying of the filling body is about 1-24 hours; (D-5) after the first stage of vacuum drying of the filling body, performing a second stage of vacuum drying of the filling body on the double-layer stack, wherein in the second stage (D-6) after the second stage vacuum drying of the filling body, the double-layer stack is subjected to a third stage vacuum drying of the filling body, wherein in the third stage vacuum drying of the filling body, the temperature of the shelf is about -50 to 0°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours; (D-7) after the second stage vacuum drying of the filling body, the double-layer stack is subjected to a third stage vacuum drying of the filling body, wherein in the third stage vacuum drying of the filling body, the temperature of the shelf is about -50 to 0°C, the condensation temperature is about - 90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours; and (D-7) after the third stage filling body vacuum drying, the double-layer stack is subjected to a fourth stage filling body vacuum drying, wherein in the fourth stage filling body vacuum drying, the shelf temperature is about 0 to 50°C, the condensation temperature is about -90 to 0°C, the vacuum degree is about 1 to 50 Pa, and the execution time is about 1-24 hours. The formed filling body comprises the microchannel support and a porous support structure formed by the uncured body of the porous support structure, and a bottom surface of the microchannel support is bonded to a top surface of the porous support structure, and the microchannel support structure has at least one microchannel, and the microchannel extends toward the bottom surface of the microchannel support structure in a manner that its channel width decreases toward the bottom surface. It is directional and extends to the bottom surface, and has an opening on the bottom surface, and the size of the opening is larger than the size of an ion but smaller than the size of a cell to allow the ion to enter the microchannel from the opening, but prevent the cell from entering the microchannel from the opening, and wherein the porous support structure has at least one hole, and the hole has a pore size larger than the opening, and the hole is non-directional relative to the microchannel. A method for preparing a filling body as claimed in claim 1, wherein the first alcohol solvent and the second alcohol solvent independently include at least one of the following: methanol; ethanol; and isopropanol. A method for preparing a filling body as claimed in claim 1, wherein the first acidic solvent and the second acidic solvent independently include at least one of the following: formic acid; acetic acid; propionic acid; and hydrochloric acid. A method for preparing a filling body as claimed in claim 1, wherein the first biodegradable natural polymer material and the second biodegradable natural polymer material independently include a biodegradable unmodified natural polymer and/or a biodegradable modified natural polymer. A method for preparing a filling body as claimed in claim 1, wherein the first biodegradable natural polymer material and the second biodegradable natural polymer material independently contain at least one of the following components: natural collagen and/or modified collagen; natural gelatin and/or modified gelatin; natural hyaluronic acid and/or modified hyaluronic acid; natural chitosan and/or modified chitosan; and natural alginate and/or modified alginate. A method for preparing a filler as claimed in claim 1, wherein the biodegradable ceramic material comprises at least one of the following components: hydroxyapatite; calcium sulfate; and calcium carbonate.