KR102458881B1 - A porous scaffold comprising a collagen and a polycarprolacton for regenerating the periodontal complex having improved healing characteristics, and method for preparing the same - Google Patents

Abstract

The present invention relates to a porous scaffold for regenerating periodontal tissue with improved healing properties containing collagen and polycaprolactone, and a method for manufacturing the same and, more specifically, to a porous scaffold for regenerating periodontal tissue, in which a periodontal tissue support can be injected into the body without side effects and is also decomposed and absorbed in the body after a certain period of time. Therefore, the porous scaffold effectively provides pores, which are effective spaces for tissue growth into the existing interior and delivery of new bones, and with high bone regeneration ability, bone regeneration is possible in a short time.

Description

A support for regeneration of porous periodontal tissue with improved healing properties including collagen, and polycaprolactone, and a method for manufacturing the same }

The present invention relates to a support for regeneration of porous periodontal tissue with improved healing properties comprising collagen and polycaprolactone, and a method for producing the same.

Bone tissue is the only hard tissue in the body, and new bone is created by filling bone tissue damaged by trauma, tumor, deformity, or physiological phenomenon with bone material. There are an autologous bone graft method in which a part of one's own bone is harvested and transplanted, an allogeneic bone graft method in which another person's bone is chemically treated and then transplanted, and a xenograft method in which a non-human animal bone is chemically treated and then transplanted (e.g., a xenograft method). It can be understood with reference to the thing of the following patent document 1). Autogenous bone transplantation, which is generally the best transplantation method, requires secondary surgery for the patient, and it is difficult to obtain the required amount, and it is difficult to perform at a general clinic. And in the case of the allograft method, secondary surgery is not required, but an immune response may occur, and although the probability is low, there is a risk of introducing a virus such as hepatitis into the patient. The xenograft method also has disadvantages in that it causes problems in use when problems such as immune response and mad cow disease occur. Bone-grafting (bone-grafting) that can easily obtain a sufficient amount of bone, has no possibility of disease transmission, has excellent biocompatibility that can replace existing graft materials, and can be properly absorbed and replaced with regenerated bone during transplantation. ) material is required.

Synthetic bone graft materials developed in response to these needs can be classified into metals, ceramics, and polymers according to materials. Materials such as metals and ceramics are mainly used as substitutes for hard tissues such as teeth and bones. Recently, taking advantage of the advantages of each material, ceramics are complexed with polymers or metals are mixed with ceramics. In particular, ceramic materials have the advantage of chemically bonding well with bones in that apatite, an inorganic component of bones and teeth, is ceramic.

Among the ceramic materials with these characteristics, the bioactive ceramics are bioactive glass, mainly composed of calcium oxide (CaO) and silicon oxide (SiO2), and calcium phosphate, composed of calcium and phosphorus, which are the main components of bone. ceramics, etc. Various calcium phosphate-based ceramic compounds have been developed as artificial bone graft materials, and hydroxyapatite (Ca10(PO4)6(OH)2, hydroxyapatite: HA) has been commercialized as a bone substitute and provided as a variety of products. The hydroxyapatite, which has excellent bone conduction performance, naturally blends with the middle tissue after implantation of the bone defect, and biochemically combines with the remaining bone to repair the shoulder joint. However, as periodic addition is required due to the characteristics of hydroxyapatite remaining in the body semi-permanently, the need for a biodegradable ceramic bone graft material that induces new bone formation while biodegrading and resorbing after transplantation has emerged. Therefore, as it becomes new bone in response to this demand, it tends to be biodegraded in the human body and absorbed into the surrounding tissues. -Ca(PO4)2, β-tricalcium phosphate: β-TCP) has been proposed and is widely used as a hard tissue replacement material used in orthopedics and dentistry. This beta-tricalcium phosphate has the advantage of being decomposed and absorbed within several years after the restoration of the bone defect, and thus is being applied to various products.

On the other hand, the ceramic bone graft material having the above characteristics is a bone substitute material that can be safely used because it does not have an immune response and has no side effects on surrounding tissues, but it is mainly granular ( Granules) form. In addition, a bone graft material of a self-hardening type has been developed due to the absence of shape processing or formability. The initial self-hardening bone graft material was a product containing hydroxyapatite, which is the same mineral component as bone after hardening, as a main component.

In addition, the most important component of a bone graft material is porosity, and a graft material containing pores with an average diameter of 150 to 850 μm is the most preferable because it helps the growth of new bone and the formation of surrounding tissues and blood vessels. Therefore, most ceramic bone graft materials are commercially available porous products regardless of their composition, and self-hardening bone graft materials are being developed in a form with high porosity. The ceramic bone graft material manufactured by sintering can form macropores with a diameter of 50 μm or more by using a sponge manufacturing method or a foaming method. However, since the final structure of the self-hardening bone graft material is determined by the hydration reaction, artificial macropores cannot be formed inside the product. This has the disadvantage of not being able to provide macropores, which are effective spaces for tissue growth into the bone graft material and delivery of new bone, so structural improvement is required for use as a bone substitute.

In addition, there is a disadvantage that the healing time after transplantation is long due to the low bone regeneration ability, so improvement is needed.

US 10-1574646 B1 (2015.11.30.)

The present invention is a problem with the existing scaffolds for periodontal tissue regeneration, which is a problem that has hardening properties but does not have macropores, so the bone regeneration effect is lowered, and has macropores but does not have sclerosis through the sponge manufacturing method or foaming method, so the material is lost. Accordingly, research was repeated to solve the problem of poor bone regeneration effect and long healing time due to low healing ability.

Therefore, by mixing beta-tricalcium phosphate, a ceramic material for regeneration of holding tissues, and polycaprolactone, a synthetic polymer material, in a specific content, and then proceeding with the process of imparting porosity, implant placement with high porosity and macropores The present invention was completed by confirming that a periodontal tissue scaffold capable of bone regeneration in a short time was formed due to its high bone regeneration ability.

Accordingly, it is an object of the present invention to provide a periodontal tissue support composition made of polycaprolactone as a structural material for collagen hardening, wherein the periodontal regeneration support composition is a new bone regeneration inducing material.

Another object of the present invention is to (a) solution the periodontal regeneration support composition; (b) mixing the solution support composition at a low temperature to form a slurry; And (c) to provide a method for preparing periodontal regeneration tissue comprising the step of freeze-drying the slurry composition.

The periodontal tissue support of the present invention relates to a support for regeneration of porous periodontal tissue that can be injected into the body without side effects and is decomposed and absorbed in the body after a certain period of time. It effectively provides artificial pores and enables bone regeneration within a short time due to its high bone regeneration ability.

1 is an SEM photograph of Example 1-1 of the present invention.
2 is an SEM photograph of Example 2-1 of the present invention.
3 is an SEM photograph of Example 3-1 of the present invention.
4 is an SEM photograph of Example 4-1 of the present invention.
5 is an SEM photograph of Example 5-1 of the present invention.
6 is an SEM photograph of Example 6-1 of the present invention.
7 is an FT-IR graph of Example 2-1 of the present invention.
8 is a photograph showing the cell proliferation test results of Examples 2-1, 3-1, 4-1, 5-1, and 6-1 of the present invention.

Hereinafter, the present invention will be described in detail.

One aspect of the present invention is

As a periodontal regeneration support made of a structural material and a new bone regeneration inducer, the structural material includes polycaprolactone, and the new bone regeneration inducer includes collagen.

The new bone regeneration inducer of the present invention can use collagen, which is a biopolymer excellent for biocompatibility and bone regeneration, and is mixed with polycaprolactone, an excellent biodegradable synthetic polymer, to prevent the loss of collagen, which is a more suitable support for periodontal tissue regeneration. can be manufactured.

In particular, polycaprolactone: collagen = 1: 0.9 to 1.1 weight ratio, more preferably polycaprolactone: collagen = 1: 1 weight ratio, which can exhibit excellent cell proliferation, improved healing properties porous periodontal formula A delay for regeneration may be provided.

The collagen has a molecular weight within a range of 5 to 15 kDa, more preferably within a molecular weight of about 10 kDa, and has a favorable decomposition period and excellent cell proliferation while exhibiting high tensile strength suitable for a support role.

The porous structure of the support body for periodontal tissue regeneration of the present invention is preferably in the form of a sponge.

Another aspect of the present invention is

A method for manufacturing a periodontal regeneration support composed of a structural material and a new bone regeneration inducing material, the method comprising:

(a) dissolving the periodontal regeneration support composition;

(b) mixing the solution support composition at a low temperature to form a slurry; and

(c) lyophilizing the slurry composition,

In step (a), polycaprolactone:collagen = 1:0.9 to 1.1 by weight, polycaprolactone and collagen are mixed in an organic solvent to form a solution.

The organic solvent may be at least one selected from acetic acid, chloroform, dichloromethane, tetrahydrofuran, dimethylformamide, and dimethylsulfoxide. and, preferably, acetic acid may be selected.

The freeze-drying step (c) may affect the final physical properties of the support. Unlike general drying, in freeze-drying, even if the solvent is evaporated and dried, the solvent remains as a void without changing the volume of the material, resulting in uniform and high-quality pores. It may be advantageous to obtain

In the present invention, freeze-drying conditions are not particularly limited, and those skilled in the art can set appropriate freeze-drying conditions, but it is preferable to proceed under vacuum conditions of -40°C and 5 mTorr, and from 24 to It may proceed for 122 hours, more preferably 48 to 96 hours, still more preferably 72 hours to 96 hours.

Hereinafter, the present invention will be described in detail through examples. However, it is clear that the following examples are only for the detailed description of the invention, and are not intended to limit the scope of the rights by this.

Example

polycaprolactone ( PCL : Polycarprolactone ) Molecular weight selection

It was confirmed that polycaprolactone (PCL) had a different decomposition period depending on the molecular weight, and accordingly, polycaprolactone sponge was prepared to select polycaprolactone suitable for the purpose of the support for regeneration of porous periodontal tissue of the present invention. It was measured by a method conventional in the art.

The results are shown in Table 1.

Molecular Weight (Da) decomposition period PCL sponge 10,000 6 months 20,000 8 months 40,000 1 year 80,000 1 year and 6 months

Considering various conditions such as implant operation period and cell regeneration time, the decomposition period of PCL forming the scaffold structure can be considered to be about 6 months to 1 year, and it is preferable that it is about 8 months, Polycaprolactone (PCL) of about 20,000 was selected and used.

Collagen, polycaprolactone ( PCL : Polycarprolactone ) solution preparation

In the present invention, the components were mixed according to the ratios shown in Table 2 below and homogenized by stirring in an acetic acid solvent at 25 °C for one day.

(1) Structural material: Polycaprolactone (PCL) was used as a material that prevents the loss of new bone regeneration material and imparts self-hardening.

(2) Organic solvent: Acetic acid was used to prepare a solution for preparing a support for periodontal regeneration.

(3) New bone regeneration material: Collagen was used as a material for alveolar bone regeneration effect, but five types of different molecular weights were used.

Example Acetic acid (mL) Polycaprolactone (mg) Collagen (mg)* 1-1 40 200 400 (1 kDa) 1-2 400 (3 kDa) 1-3 400 (5 kDa) 1-4 400 (10 kDa) 1-5 400 (30 kDa) 2-1 400 400 (1 kDa) 2-2 400 (3 kDa) 2-3 400 (5 kDa) 2-4 400 (10 kDa) 2-5 400 (30 kDa) 3-1 800 400 (1 kDa) 3-2 400 (3 kDa) 3-3 400 (5 kDa) 3-4 400 (10 kDa) 3-5 400 (30 kDa) 4-1 1200 400 (1 kDa) 4-2 400 (3 kDa) 4-3 400 (5 kDa) 4-4 400 (10 kDa) 4-5 400 (30 kDa) 5-1 1600 400 (1 kDa) 5-2 400 (3 kDa) 5-3 400 (5 kDa) 5-4 400 (10 kDa) 5-5 400 (30 kDa) 6-1 2000 400 (1 kDa) 6-2 400 (3 kDa) 6-3 400 (5 kDa) 6-4 400 (10 kDa) 6-5 400 (30 kDa) * Five types of collagen with different molecular weights were used, and the numbers of collagens with different molecular weights are the branch numbers of each example (1: 1 kDa, 2: 3 kDa, 3: 5 kDa, 4: 10 kDa, 5: 30 kDa)

In the step of preparing the solution, polycaprolactone was added to the organic solvent and stirred at a speed of 300 to 500 rpm for 12 to 72 hours. The organic solvent added to the polycaprolactone was acetic acid, chloroform ( chloroform), dichloromethane, tetrahydrofuran, dimethylformamide, or dimethylsulfoxide may be used, but acetic acid is preferably used.

polycaprolactone ( PCL : Polycarprolactone ), Collagen Low Temperature mix

In order to slurry the periodontal regeneration support prepared above, each example was added to a 100 ml glass bottle and stirred at a speed of 300 to 500 rpm for 12 to 72 hours at 4°C.

freeze drying

Using the frozen periodontal regeneration support solution prepared above, freeze-drying was carried out for 72 to 96 hours under vacuum conditions of -40°C and 5 mTorr using the freeze-drying machine to give the pores in the form of sponges.

SEM and surface confirmation via FT-IR

The porosity of the prepared periodontal regeneration scaffold was confirmed through SEM.

In Examples 1-1 to 1-5, when the ratio of collagen to polycaprolactone was 50% or less, collagen could not be bound, and a powder form, not a sponge form, appeared (see FIG. 1 ).

Conversely, in Examples 2-1 to 2-5, 3-1 to 5, 4-1 to 4-5, 5-1 to 5-5, and 6-1 to 6-5, a sponge-type pore structure was shown ( 2 to 6). However, there were some differences between the Examples in the size of the average pore size, porosity, pore shape, etc., which is expected to affect cell proliferation, which will be described later.

On the other hand, in order to confirm that the prepared periodontal regeneration support is a well-mixed support, the components were confirmed through FT-IR analysis (FIG. 7).

The peak shown at 2900 1700 shows the presence of PCL, and the peak at 1500 was confirmed, confirming the presence of collagen. This shows good mixing.

Confirmation of cell proliferation

In order to confirm the cell proliferative properties of the prepared periodontal regeneration scaffold, it was confirmed by performing a cell experiment. However, in the case of Examples 1-1 to 1-5, it was excluded from the cell experiment in the form of powder.

The results were as shown in FIG. 8, and it was confirmed that the cell proliferation was the best in Example 2-1, and the only tissue differentiation occurred after the 3rd day. Accordingly, it was confirmed that the polycaprolactone:collagen = 1:1 ratio is the most preferable in terms of cell proliferation.

Check tensile strength and decomposition period

Physical properties such as tensile strength and decomposition period, which are important physical properties for commercialization, were measured for Examples 2-1 to 2-5, which are most effective in terms of cell proliferation.

The measurement results are shown in Table 3 below.

Example molecular weight [kDa] Tensile strength [MPa] Decomposition period [weeks] cell proliferation [%] 2-1 One One One 120 2-2 3 2 2 130 2-3 5 3 4 140 2-4 10 6 12 160 2-5 30 6 22 130

As shown in Table 3, although the tensile strength of collagen shows a tendency to increase according to the molecular weight, it is not directly proportional.

In addition, it was confirmed that the molecular weight of about 10 kDa is suitable as a cell support, and 10 kDa with a decomposition period of 12 weeks is most suitable for use as a bone graft material.

Claims (10)

In the periodontal regeneration support consisting of a structural material and a new bone regeneration inducing material,
The structural material includes polycaprolactone,
The new bone regeneration inducer includes collagen,
Polycaprolactone: Collagen = 1: 0.9 to 1.1 as a weight ratio,
The support has a porous structure,
The collagen is a support for periodontal tissue regeneration, characterized in that within the molecular weight range of 5 ~ 15 kDa. The support for periodontal tissue regeneration according to claim 1, wherein polycaprolactone:collagen = 1:1 by weight. delete The support for periodontal tissue regeneration according to claim 1, wherein the collagen has a molecular weight of 10 kDa. The support for periodontal tissue regeneration according to claim 1, wherein the porous structure is in the form of a sponge. The support for periodontal tissue regeneration according to claim 1, wherein the polycaprolactone has a molecular weight of 20,000 Da. A method for manufacturing a periodontal regeneration support composed of a structural material and a new bone regeneration inducing material, the method comprising:
(a) dissolving the periodontal regeneration support composition;
(b) mixing the solution support composition at a low temperature to form a slurry; and
(c) comprising the step of freeze-drying the slurried periodontal regeneration support composition,
The step (a) is to mix polycaprolactone and collagen in an organic solvent at a weight ratio of polycaprolactone:collagen = 1:0.9 to 1.1 to form a solution,
The collagen is a method of producing a periodontal regeneration scaffold, characterized in that within the molecular weight range of 5 ~ 15 kDa. The method according to claim 7, wherein the organic solvent is selected from acetic acid, chloroform, dichloromethane, tetrahydrofuran, dimethylformamide, and dimethylsulfoxide. A method of manufacturing a periodontal regeneration support, characterized in that at least one type. The method according to claim 7, wherein the step (c) comprises freeze-drying at -40°C under vacuum conditions of 5 mTorr. The method according to claim 7, wherein the step (c) is freeze-dried for 24 to 122 hours.

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