Medical material

Abstract

This medical material comprises a hydrogel sheet including a base part, an openable / closable grip part, and a slit for separating a part of the grip part from the base part.

Description

medical supplies

[0001] This application claims priority to Japanese Patent Application No. 2024-005973, filed January 18, 2024, the contents of which are incorporated herein by reference.

[0002] Perforated eardrums caused by otitis media or trauma affect 100,000 people annually in Japan alone. Hearing loss is one of the three major risk factors for dementia, and treatment of perforated eardrums and hearing loss is important for preventing dementia. Hearing aids cannot be used in ears with perforated eardrums because they can be damaged by ear discharge, which not only increases the risk of dementia in patients with perforated eardrums but also significantly reduces their quality of life.

[0003] During tympanic membrane reconstruction surgery, it is necessary to securely attach and adhere a dense collagen membrane to the inside of the eardrum, on the middle ear side. However, conventional dense collagen membranes are difficult to grasp, and there is a risk that they may be sucked in and lost, or may migrate to an unintended location.

[0004] Furthermore, if the defect in the middle ear mucosa (exposed bone surface) is extensive during surgery for otitis media, regeneration of the middle ear mucosa becomes insufficient, leading to complications such as adhesions. However, there are currently no medical materials that can cover the defect in the middle ear mucosa, which is leaking a large amount of exudate, and promote mucosal regeneration.

[0005] In order to improve such uncertainty and poor operability, the inventors have developed a dried vitrigel membrane having a gripping thread portion and a surface portion integrally formed therewith (see, for example, Patent Document 1).

[0006] Patent No. 7350238

[0007] The use of the dried vitrigel membrane described in Patent Document 1 significantly improved handling, but the manufacturing of such a dried vitrigel membrane was difficult, and the grasping thread portion sometimes got in the way, leaving room for further improvement. The present invention has been made in view of the above circumstances, and provides a medical material that is easy to manufacture and has excellent handling properties.

[0008] The present invention includes the following aspects. [1] A medical material comprising a hydrogel sheet including a base, an openable / closable gripping portion, and a slit separating a portion of the gripping portion from the base. [2] The medical material according to [1], wherein the gripping portion is openable / closable in a direction intersecting the sheet surface of the hydrogel sheet. [3] The medical material according to [1], wherein the gripping portion is surrounded by the base. [4] The medical material according to [1], wherein the slit is formed obliquely with respect to the sheet surface in a cross-sectional view of the sheet cut along the direction in which the gripping portion extends from the base. [5] The medical material according to [1], which is for membrane regeneration or mucosa or epithelium regeneration. [6] The medical material according to [1], wherein the slit is U-shaped. [7] The weight per unit area of ​​the hydrogel sheet is 0.1 mg / cm ２ ~50 mg / cm ２ The medical material according to [1],

[0009] According to the present invention, it is possible to provide a medical material that is easy to manufacture and has excellent handling properties.

[0010] 1. A front view of the medical material 100 of this embodiment. 2. A cross-sectional view of the medical material 100 in FIG. 1 taken along line II-II. 3. A cross-sectional view of the medical material 100 in FIG. 1 taken along line III-III. 4. A front view showing an example of a medical material of this embodiment. 5. A cross-sectional view of the medical material 100 taken along line VI-VI. 6. A front view of a medical material with dimples taken along line VIII-VIII. 7. A cross-sectional view of the medical material in FIG. 8 taken along line VIII-VIII. 8. (A-E) Photographs showing a process for confirming the function of a gripping structure using parafilm. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 19. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 19. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 39. 31. 32. 33. 34. 35. 36. 37. 38. 39. 39. 39. 39. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61

[0011] Hereinafter, embodiments of the present invention will be described in detail, with reference to the drawings where necessary. Note that the dimensional ratios in the drawings may be exaggerated for the purpose of explanation and do not necessarily correspond to the actual dimensional ratios.

[0012] Medical Material In one embodiment, the present invention provides a medical material comprising a hydrogel sheet including a base, an openable and closable gripping portion, and a slit separating a portion of the gripping portion from the base.

[0013] 1 is a front view of a medical material 100. The medical material 100 has a base 103 and an openable / closable gripping portion 102 on a hydrogel sheet. A slit 101 provided in the hydrogel sheet separates a portion of the gripping portion 102 from the base 103. This separation defines the gripping portion 102.

[0014] FIG. 2 is a cross-sectional view of the medical material 100 taken along line II-II in FIG. 1 . In a cross-sectional view of the hydrogel sheet cut along the direction in which the gripping portion 102 extends from the base 103, the slits 101 are formed at an angle relative to the surface of the hydrogel sheet. This strengthens the bond between the gripping portion 102 and the base 103 and maintains the gripping structure in this embodiment. In this embodiment, the slits are formed at an angle and the front and back slits are offset, allowing the gripping portion to automatically retract when released after gripping. Furthermore, the slits close completely, resulting in a flat surface (on both sides) and no gaps remaining. In other words, in this embodiment, the regenerated cell sheet is smooth and has no steps. FIG. 3 is a cross-sectional view of the medical material 100 taken along line III-III in FIG. 1 . In a cross-sectional view of the hydrogel sheet cut along a direction perpendicular to the direction in which the gripping portion 102 extends from the base portion 103, the slit 101 is formed perpendicular to the surface of the hydrogel sheet.

[0015] As shown in FIG. 1 , the portion separated by the slit 101 functions as a gripping portion 102. The gripping portion 102 can be opened and closed in a direction intersecting the sheet surface of the hydrogel sheet. The gripping portion 102 is surrounded by a base 103 and has an openable and closable valve structure. The shape of the slit 101 is not particularly limited as long as it can form the gripping portion 102, and examples include a square shape, a U-shape (arc-shaped / semicircular shape), or a triangle, with a U-shape being preferred. The shape of the slit 101 may be any shape that allows for gripping, and may be linear, for example, wavy, or rectangular, for example, straight.

[0016] The size of the gripping portion formed by the slit is not particularly limited. For example, if the gripping portion has a U-shape, the diameter is preferably 0.5 to 30 mm, and more preferably 1.5 to 3.0 mm. For example, a gripping portion having such a diameter can be formed by post-processing, such as by pressing a 23G needle with a U-shaped tip against the needle. In this case, the width of the slit depends on the width of the needle and is less than 1 mm.

[0017] The number of slits in the medical material of this embodiment is not particularly limited and may be increased or decreased depending on the area of ​​the hydrogel sheet. When the medical material is for human eardrums or animals, the number of slits is preferably one, as shown in FIG. 1. When the medical material is for the human middle ear, the number of slits is preferably multiple, as shown in FIG. 4. The arrangement of the slits in the medical material of this embodiment is adjusted as appropriate depending on the convenience of the surgery or treatment. Because the hydrogel sheet is cut to fit the shape of the patient's affected area, it is preferable that the slits be evenly arranged, as shown in FIG. 4, so that the biomedical material will have slits regardless of the shape it is cut into.

[0018] The shape of the hydrogel sheet in the medical material of this embodiment is not particularly limited, and examples include polygons such as triangles, quadrilaterals (including squares, rectangles, and trapezoids), pentagons, hexagons, heptagons, and octagons; circles, ellipses, nearly circles, ellipses, nearly ellipses, semicircles, and sector shapes. The shape and size of the hydrogel sheet are appropriately cut depending on the shape of the affected area. For example, for use in human eardrums, a circular medical material with a diameter of 8 mm is envisioned, and for use in human middle ears, a circular medical material with a diameter of 3 cm is envisioned.

[0019] The area of ​​the medical material of this embodiment can be appropriately set as needed, for example, 1 mm ２ ~400cm ２ For example, 20 mm ２ ~40cm ２ For example, 80 mm ２ ~4cm ２ may be.

[0020] The medical material of this embodiment may have a flat, curved, or textured surface, and can be used depending on the application. The thickness of the medical material of this embodiment can be appropriately set as needed, and may be, for example, 0.1 μm to 5 mm, for example, 2 μm to 1 mm, or for example, 20 μm to 400 μm. Furthermore, the thickness of the medical material of this embodiment may be uniform or non-uniform.

[0021] The weight per unit area of ​​the medical material of this embodiment is 0.1 mg / cm ２ ~50 mg / cm ２ is preferred, and 0.5 mg / cm ２ ~5 mg / cm ２ The thinner the hydrogel sheet, the softer it is, and the easier it is to fit the uneven surface of the wound, and the easier it is to transmit moisture such as exudate, but the sheet tends to curl up, making it difficult to handle. ２ More than 1 mg / cm is preferred. ２ More preferably, 1.4 mg / cm ２　 The weight is more preferably 2 mg / cm for eardrum regeneration. ２ More than 3 mg / cm is preferred.２ More preferably, 4 mg / cm ２　 On the other hand, as will be described later in the Examples, Neoveil Sheet (registered trademark; PGA) has coarse fibers that are unable to cover the wound surface and do not promote mucosal regeneration.

[0022] The medical material 100 has a gripping portion 102, which significantly reduces surgical time and makes it easier to fix the medical material to the wound surface without being washed away by exudate. Furthermore, even if exudate seeps from a wound in a living body, the formation of the gripping portion allows the exudate to pass through holes created in the medical material 100. Furthermore, the examples described below have confirmed that the regeneration of the middle ear mucosa and tympanic membrane can be significantly promoted. The development of a new medical material with this high exudate permeability and gripping mechanism will enable more reliable, rapid reconstructive surgery and procedures that are less invasive.

[0023] The medical material of this embodiment preferably does not have through-holes (perforations). When the medical material of this embodiment is implanted into the middle ear bone wall, if the medical material has through-holes, as shown in Figures 5 and 6, the medical material will fit and adhere to the irregularities of the middle ear bone wall, allowing exudate from the bone to pass through the through-holes, but this will result in unevenness in the regenerated mucosal tissue. If it is desired to increase the permeability of exudate, the medical material of this embodiment preferably has dimples rather than through-holes, as shown in Figures 7 and 8.

[0024] In this specification, the term "sol," which is the raw material for "hydrogel," refers to a substance in which dispersoid colloidal particles (size: approximately 1 to several hundred nm) in a liquid as a dispersion medium are composed, in particular, of polymer compounds. More specific examples of sols include aqueous solutions of natural polymer compounds and synthetic polymer compounds. When these polymer compounds are crosslinked by chemical bonding to form a network structure, the sol transitions to a "hydrogel," which is a semi-solid substance that retains a large amount of water in the network. In other words, a "hydrogel" refers to a sol that has been gelled.

[0025] The sol used as the raw material for the hydrogel may be any biocompatible material, and examples thereof include natural polymer compounds such as gelling extracellular matrix-derived components, fibrin, agar, agarose, and cellulose, and synthetic polymer compounds such as polyacrylamide, polyvinyl alcohol, polyethylene oxide, and poly(II-hydroxyethylmethacrylate) / polycaprolactone.

[0026] Examples of gelling extracellular matrix-derived components include, but are not limited to, collagen (type I, type II, type III, type V, type XI, etc.), basement membrane components reconstituted from mouse EHS tumor extract (including type IV collagen, laminin, heparan sulfate proteoglycan, etc.) (trade name: Matrigel), glycosaminoglycans, hyaluronic acid, proteoglycans, and gelatin. The desired hydrogel can be produced by selecting the optimal salts and other components for gelation, their concentrations, pH, etc. Furthermore, by combining raw materials, hydrogels that mimic various in vivo tissues can be obtained.

[0027] Among these, gelling extracellular matrix-derived components are preferred as the sol, with collagen being more preferred. Among collagen, examples of more preferred raw materials include native collagen and atelocollagen, with atelocollagen being even more preferred.

[0028] The term "vitrigel" refers to a stable gel obtained by vitrifying a conventional hydrogel, in which free water is completely removed from the hydrogel and then the bound water is partially removed, followed by rehydration. The inventors have named this gel "vitrigel (registered trademark)." In this specification, a dried hydrogel immediately after the vitrification process and without a rehydration process is simply referred to as a "dried hydrogel." A gel obtained by a rehydration process after the vitrification process is referred to as "vitrigel," and a dried vitrigel obtained by vitrifying the vitrigel is referred to as a "dried vitrigel." Therefore, "vitrigel" is a hydrated form. In this specification, the term "vitrigel" may be omitted. In this specification, the term "hydrogel" conceptually includes "vitrigel." In this specification, the term "hydrogel sheet" conceptually includes a "dried hydrogel sheet."

[0029] <Uses> The medical material of this embodiment has an openable and closable gripping portion defined by a slit, and is therefore suitable for use in, for example, surgery that requires complex manipulations before reaching the application site. Specifically, the medical material of this embodiment is suitable for application to the inner wall of the esophagus via the esophagus, application to the eardrum via the external auditory canal, and fixation to various wounds.

[0030] The medical material of this embodiment is preferably used for membrane regeneration or mucosal or epithelial regeneration. Examples of application locations for the medical material of this embodiment include the middle ear, tympanic membrane, external auditory canal, nasal cavity, and paranasal sinuses. When the medical material of this embodiment is applied to the middle ear, tympanic membrane, or external auditory canal, the medical material of this embodiment is preferably used for tympanic membrane regeneration or middle ear mucosa regeneration. The medical material of this embodiment can also be used for oral mucosa, pharyngeal mucosa, oral mucosa, or gastrointestinal mucosa. The medical material of this embodiment is suitable for use in the treatment of tympanic membrane perforation. In intractable otitis media, tympanic membrane perforations do not heal spontaneously, and fascia is usually used, but this is highly invasive to the patient and requires difficult surgical procedures. Since the tympanic membrane regenerates by extending into the air, the presence of a scaffold promotes regeneration. Furthermore, the properties of the epithelial layer (stratified squamous epithelium) and the mucosal layer (mucosa) of the tympanic membrane differ significantly. The epithelial layer of the tympanic membrane constantly migrates from the center to the periphery and then outward from the ear canal at a rate of 0.07 mm / day. Therefore, if a scaffold is applied to the epithelial layer, i.e., the outer surface of the tympanic membrane, it will shift at a rate of 0.07 mm / day. Therefore, by using the underlay method, in which the medical material of this embodiment is applied to the middle ear side, where migration does not occur, the medical material of this embodiment functions as a scaffold for a long period of time. Even in animal experiments, tympanic membrane reconstruction must be performed using the underlay method, just like in human surgery. Tympanic membrane reconstruction in tympanic membrane reconstruction procedures such as endoscopic tympanoplasty requires a skin incision and the collection of tympanic membrane reconstruction materials such as subcutaneous connective tissue, perichondrium, or cartilage. However, the medical material of this embodiment allows tympanic membrane reconstruction without a skin incision.

[0031] Furthermore, when applied to a defective area of ​​middle ear mucosa during middle ear surgery, the medical material of this embodiment functions as an absorbable artificial middle ear mucosa that promotes autologous middle ear mucosal regeneration. The medical material of this embodiment, which has an openable and closable gripping portion defined by a slit, is an optimal solution for middle ear mucosal regeneration therapy. It is suitable for use not only in chronic otitis media, but also in tympanic membrane regeneration due to adhesive otitis media and cholesteatoma. It can also provide an innovative new treatment for intractable otitis media that cannot be fully addressed by tympanic membrane regeneration alone. The medical material of this embodiment is minimally invasive to the patient, facilitating surgery.

[0032] [Method for treating tympanic membrane perforation] The method for treating tympanic membrane perforation in this embodiment includes the steps of grasping the gripping portion of the medical material and passing the medical material through the tympanic membrane perforation from the outer ear side to the middle ear side, and pulling the medical material that has passed through the tympanic membrane perforation from the middle ear side to the outer ear side, and attaching the surface of the medical material to the middle ear side of the tympanic membrane.

[0033] <<Manufacturing Method>> The medical material of this embodiment is manufactured by post-processing a hydrogel sheet, such as by pressing it with a needle having a U-shaped tip. Examples of methods for manufacturing a hydrogel sheet include the following methods.

[0034] First, a sol is prepared. When the sol to be injected is a collagen sol, the collagen sol can be prepared using a solution having an optimal salt concentration, such as physiological saline, phosphate-buffered saline (PBS), HBSS (Hank's Balanced Salt Solution), a basal culture medium, a serum-free culture medium, or a serum-containing culture medium. The pH of the solution during collagen gelation can be set to, for example, 6 to 8. The collagen sol can be prepared at, for example, about 4°C.

[0035] In particular, when a serum-free culture medium is used, it is possible to avoid the inclusion of substances contained in other animal serum components that are unsuitable for application to wounds in living bodies (e.g., antigens, pathogenic factors, etc.) in the hydrogel, making the hydrogel membrane obtained using the serum-free culture medium suitable for medical use.

[0036] Furthermore, the concentration of the collagen sol used to produce the hydrogel is preferably 0.1 to 1.0% by mass, and more preferably 0.2 to 0.6% by mass. When the collagen sol concentration is equal to or higher than the above-mentioned lower limit, gelation is not too weak, and when the collagen sol concentration is equal to or lower than the above-mentioned upper limit, a hydrogel consisting of a uniform collagen gel can be obtained.

[0037] The sol is then allowed to stand to gel, yielding a hydrogel sheet. The temperature at which the sol is kept warm can be adjusted appropriately depending on the type of sol used. For example, when the sol is a collagen sol, the temperature at which gelation occurs can be lower than the denaturation temperature of the collagen, which depends on the animal species of the collagen used. Generally, gelation can be achieved within a few minutes to a few hours by keeping the temperature at 20°C or higher and 37°C or lower.

[0038] Next, the hydrogel sheet may be irradiated with ultraviolet light. A known ultraviolet light irradiation device can be used for ultraviolet light irradiation. The irradiation energy is set so that the total irradiation amount per unit area is 0.1 mJ / cm. ２ ~6000mJ / cm ２ and preferably 10 mJ / cm ２ ~4000mJ / cm ２ More preferably, 100 mJ / cm ２ ~3000mJ / cm ２ More preferably, 200 mJ / cm ２ ~1500mJ / cm ２ It is particularly preferable that the total irradiation amount is within the above range. When the total irradiation amount is within the above range, the transparency and strength of the hydrogel sheet can be particularly preferable. If the transparency of the hydrogel sheet hinders operability, the ultraviolet irradiation step may be omitted.

[0039] When the total amount of ultraviolet light irradiated per unit area is the same, the transparency and strength of the hydrogel sheet can be further improved by dividing the ultraviolet light irradiated onto the hydrogel sheet and repeating the process multiple times.

[0040] Next, the hydrogel sheet is dried. By drying the hydrogel sheet, free water in the hydrogel sheet can be completely removed and further partial removal of bound water can be promoted. The longer the period of this vitrification process (a process of completely removing free water in the hydrogel sheet and then partially removing bound water) is, the stronger the vitrigel sheet can be obtained when rehydrated.

[0041] Various drying methods can be used, such as air drying, drying in a sealed container (air is circulated in the container to constantly supply dry air), drying in an environment with silica gel placed, etc. Examples of air drying methods include drying for two days in an incubator kept sterile at 10°C and 40% humidity, or drying at room temperature for one day and one night in a sterile clean bench.

[0042] A hydrogel sheet or a dried hydrogel sheet can be obtained through the above steps. When a thicker hydrogel sheet or a dried hydrogel sheet is desired to be produced, it is preferable to repeat the steps of layering a sol on the hydrogel sheet, leaving the layered sol to gel, and drying the layered hydrogel sheet.

[0043] The dried hydrogel sheet described above is hydrated to obtain a vitrigel sheet, and the dried vitrigel sheet is then dried to obtain a vitrigel sheet. Examples of aqueous solutions used for hydration include sterilized water, physiological saline, and PBS. It is preferable to repeat the hydration by appropriately replacing the aqueous solution.

[0044] The present invention will be described below with reference to examples, but the present invention is not limited to the following examples.

[0045] [Verification of the function of the gripping structure using parafilm] Parafilm was cut into a circle with a diameter of 6 mm (see FIG. 9(A)), and slit using a slit-making device (see FIG. 9(B)). As shown in FIGS. 9(C) and (D), gripping portions were formed by the slitting, and the piece could be held with forceps. As shown in FIG. 9(E), it was confirmed that the circular parafilm after the manipulation was almost completely intact and had returned to its original state.

[0046] [Production of Vitrigel Membrane with Grip Portions] The revitrified dried atelocollagen vitrigel sheet was cut into a circle with a diameter of 6 mm, and slit using a slit-making device. As shown in Figure 10, grip portions were formed by slitting, and a vitrigel membrane with grip portions was obtained. This vitrigel membrane with grip portions could be held with forceps.

[0047] [Rat middle ear mucosal regeneration experiment] The above-mentioned vitrigel membrane with gripping parts was used as a collagen membrane for tympanic membrane reconstruction, and endoscopic otologic surgery was performed on a temporal bone surgery model. The surgical conditions were as follows. As a control, a conventional PGA sheet (Neoveil (registered trademark); circular, 6 mm diameter) was used.

[0048] Perforation size: 4 mm diameter Vitrigel membrane: 6 mm diameter, 1.4 mg / cm ２ Endoscope used: 4mm diameter rigid scope Olympus ear forceps Rosen probe weakly curved

[0049] Figure 11 shows a photograph of the wound four days after implantation. The vitrigel membrane with grips fit the target. On the other hand, the Neoveil membrane had coarse fibers and failed to cover the wound surface. Furthermore, the results of HE staining of tissue sections are shown in Figure 12. In rats treated with Neoveil, mucosal defects were observed, and mucosal cells were not aligned. In contrast, in rats treated with the vitrigel membrane with grips, mucosal cells were clearly aligned. Neoveil's coarse fibers were unable to cover the wound surface, and it was confirmed that it was unable to adequately promote middle ear mucosal regeneration. On the other hand, the vitrigel membrane with grips was confirmed to cover and protect the middle ear mucosal defect and promote middle ear mucosal regeneration. By providing slits in the vitrigel membrane, exudate from the middle ear bone wall was able to pass through, allowing the vitrigel to maintain adhesion to the middle ear bone surface (mucosal defect surface). It was also confirmed that the slits did not adversely affect mucosal cell proliferation.

[0050] [Rat Tympanic Membrane Perforation Regeneration Experiment] Using a rat model of tympanic membrane perforation created by heat, tympanic membrane regeneration was performed using the underlay method with a vitrigel membrane to examine its effectiveness. Tympanic membrane regeneration was also performed using a conventional collagen sponge using the underlay method, and its effectiveness was compared. Results of tympanic membrane perforation size on the seventh day of treatment are shown in Figures 13 and 14. When collagen sponge was used, the tympanic membrane perforation could not be closed, and granulation tissue was observed. On the other hand, the tympanic membrane perforation was able to be closed with a vitrigel membrane.

[0051] [Study on the thickness of the vitrigel membrane with gripping parts] If the vitrigel membrane with gripping parts used in middle ear surgery is too thin, it will bend, and if it is too thick, it will not adhere well to the middle ear bone wall. The vitrigel membrane with gripping parts needs to be permeable to exudate. Therefore, the thickness of the vitrigel membrane with gripping parts was studied. The dense collagen sheet used in the study is shown below.

[0052] Atelocollagen vitrigel diameter 1.5 mm 1.4 mg / cm ２ (for eardrum experiments) 0.7 mg / cm ２ 0.5 mg / cm ２

[0053] When the vitrigel membrane with grip parts was thin, it tended to stick to the petri dish due to the effects of static electricity and was easily affected by the surface tension of the aqueous solution. On the other hand, when the vitrigel membrane with grip parts was thin, the aqueous solution penetrated quickly. ２ When placed in saline, the vitrigel membrane with gripping parts tended to become transparent and lose its visibility, and curled up into a ball. ２ The vitrigel membrane with gripping parts spread when placed in saline, and was easy to handle when using an applicator.

[0054] Next, UV irradiation of the vitrigel membrane with gripping parts was examined. The vitrigel membrane with gripping parts used in the examination is shown below.

[0055] Atelocollagen vitrigel diameter 1.5 mm 0.7 mg / cm ２　 No UV irradiation 0.7 mg / cm ２　 UV 80mJ / cm ２0.7 mg / cm ２　 UV800mJ / cm ２ 0.5 mg / cm ２　 No UV irradiation 0.5 mg / cm ２　 UV 80mJ / cm ２ 0.5 mg / cm ２　 UV800mJ / cm ２

[0056] 0.5 mg / cm ２　 UV800mJ / cm ２ The vitrigel membrane with gripping parts became even more transparent. The hardness of the 1.5 mm diameter vitrigel membrane did not change much compared to that without UV irradiation.

[0057] 0.7 mg / cm ２ Regarding the effect of UV irradiation on the grip-equipped vitrigel membrane, the one without UV irradiation was more flexible and had properties somewhat similar to jelly. It was easier to fit uneven surfaces and to place on the applicator. The water content also seemed to be higher without UV irradiation, and it became slightly thicker, making it easier to use. 0.7 mg / cm ２　 UV800mJ / cm ２ The membrane itself was easy to handle, but nearly transparent. It was somewhat hard and less flexible, making it difficult to fit to uneven surfaces, and sometimes it would repel when trying to place it on the applicator, making it impossible to place. The water content seemed to be somewhat low. For middle ear mucosa regeneration, 0.7 mg / cm ２　 A vitrigel membrane with a gripper without UV irradiation is preferred, and 1.4 mg / cm ２　 The vitrigel membrane with gripping parts without UV irradiation was more preferable. For tympanic membrane regeneration, a 4.2 mg / cm thick membrane with a three times thicker membrane was used. ２ It was confirmed to be preferable.

[0058] According to the present invention, it is possible to provide a medical material that is easy to manufacture and has excellent handling properties.

[0059] 100...medical material, 101...slit, 102...gripping portion, 103...base portion.

Claims

1. A medical material comprising a base portion, an openable and closable gripping portion, and a slit that separates a part of the gripping portion from the base portion.

2. The medical material according to claim 1, wherein the gripping portion is openable and closable in a direction intersecting the sheet surface of the hydrogel sheet.

3. The medical material according to claim 1, wherein the gripping portion is surrounded by the base portion.

4. The medical material according to claim 1, wherein the slit is formed obliquely with respect to the sheet surface in a cross-sectional view of the sheet cut along the direction in which the gripping portion extends from the base portion.

5. The medical material according to claim 1, which is for membrane regeneration or mucosal or epithelial regeneration.

6. The medical material according to claim 1, wherein the slit is U-shaped.

7. The weight per unit area of the hydrogel sheet is 0.1 mg / cm ２ to 50 mg / cm ２ The medical material according to claim 1.

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