WO2015177926A1

WO2015177926A1 - Artificial skin for suture training and method for manufacturing same

Info

Publication number: WO2015177926A1
Application number: PCT/JP2014/063711
Authority: WO
Inventors: 治高木; 充正鈴木; 秀明安藤
Original assignee: 株式会社レジーナ; 国立大学法人秋田大学
Priority date: 2014-05-23
Filing date: 2014-05-23
Publication date: 2015-11-26

Abstract

[Problem] To provide an artificial skin for suture training, said artificial skin being less sticky to the skin surface than silicone articles and ensuring the provision of a real surface shape after suturing. [Solution] An artificial skin for suturing and ligating a wound in the skin by sewing with a surgical suture, said artificial skin having a structure consisting of at least three layers formed of a polyurethane-based material and provided with: a flexible epidermal layer (11) that is formed thinly in imitation of the skin epidermis; a flexible dermal layer (12) that is formed thicker than a surface layer in imitation of the skin dermis; and a flexible subcutaneous layer (13) that is formed thicker than an intermediate layer in imitation of the skin subcutaneous tissue.

Description

Artificial skin for practicing suture and method for producing the same

[Technical Field] The present invention relates to an artificial skin for practicing suture for operating a suture using a surgical suture and ligating a wound of a hiff, and a manufacturing method thereof.

Various teaching materials have been used to learn surgical techniques, and various teaching materials have been provided so far for suturing skin wounds, that is, cuts. Conventional artificial skin or similar material used as a teaching material for stitching is made of vinyl chloride or silicone resin, and has a sticky feeling on the surface, and the surface form after stitching has a problem of poor realism. . In addition, if the thread is pulled strongly at the time of suturing, the resin itself may be suddenly cut. In this case, the surface does not wrinkle, so that there is a problem that it is not possible to determine whether the force when pulling the suture is increased or decreased.

Examining the prior art, for example, there is an invention related to a simulated organ tube for suture practice of JP2013-015789A. It is a food-like viscous liquid prepared by mixing raw materials made of food ingredients with water, which is gelled and molded into a shape that mimics the required organs of the human body, while the skin-like film of the human body is formed on the surface. The gel strength and the penetration resistance having the form and feel of the required organs of the human body are described as being adjusted to the degree approximate to the body.

The above-mentioned invention has a layer structure that is very similar to a real skin structure with a hard outer skin and soft contents. Therefore, a suture practice in accordance with the same situation and feel as in an actual operation, that is, a key shape that cannot be obtained with a conventional product, Y It is said that an arbitrary wound such as a letter shape and a debridement edge can be made to perform a stitching practice and a stitching practice to prevent a stitching step and a dog-ear. However, it is difficult to accurately determine whether or not the suture sutures the affected part appropriately.

Also, there is an invention of Japanese Patent Application Laid-Open No. 2010-085512, which describes the use of pig skin as a human skin substitute. However, when the skin of pigs becomes permanent, new problems such as storage and preparation for use appear. Further, it is described that an artificial material made of silicon resin or the like may be used instead of pig skin, but as described above, the resin does not meet the object of the present invention.

JP2013-015789A JP 2010-085512

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and its object is to provide an artificial skin for practicing sutures that does not have a sticky feeling like a silicone product on the surface of the skin and that provides a realistic surface form after stitching. That is. Another object of the present invention is to provide an artificial skin for practicing sutures that facilitates all sutures including dermis sutures.

In order to solve the above-mentioned problems, the present invention is a flexible epidermis that is formed thinly by imitating the epidermis of a hiff as an artificial skin that is carried using a surgical suture and is sutured and ligated. A soft dermis layer formed to have a thickness equal to or greater than the surface layer, imitating the dermis of the hive, and a soft subcutaneous layer formed to have a thickness equal to or greater than the intermediate layer, imitating the subcutaneous tissue of the hive And at least a three-layer structure made of polyurethane-based material. A structure of at least three layers made of a polyurethane-based material is a minimum element, and it is naturally acceptable to fill this element with a more complicated layer structure.

The present invention is intended for practicing suturing, and is particularly suitable for practicing general skin suturing, and is an artificial skin suitable for a technique called dermal suturing. For general stitching, the quality of the procedure can be determined by the wrinkle state. Dermal suturing is a method in which a thread is ligated between the dermis and subcutaneous tissue, and the thread does not appear on the surface and the appearance of the wound is clean, but it is a technique that takes time and requires proficiency.

The three-layer structure of the epidermis layer, the dermis layer and the subcutaneous tissue is particularly effective for facilitating suturing and determining the suturing result. The epidermis layer is thinly and flexibly formed by a resin material, imitating the epidermis of Hiff, the dermis layer is flexibly formed to a thickness greater than the superficial layer by imitating the dermis of Hiff, and the subcutaneous layer is the subcutaneous tissue of Hif It is flexibly formed to a thickness of the intermediate layer or more by a resin material. Each of the resin materials is made of a polyurethane-based material.

In the present invention, it is preferable to use a polyurethane-based material for forming each layer. There are many types of polyurethane, the reaction to heat is not uniform, and it can be said that it belongs to two types of thermoplasticity and thermosetting. However, all of them are polyurethane-based materials, and by using these three types to form a three-layer structure, there is also an advantage that a feeling close to the human body can be obtained with rich stretchability. A colorant is blended in the polyurethane material. Moreover, a solvent, a hardening | curing agent, etc. are mix | blended with each layer of an epidermis layer, a dermis layer, and a subcutaneous layer for hardness adjustment.

Specifically, a dispersion system in which a polyether polyol-based or polyester polyol-based polyol is a main agent, an aromatic isocyanate or an aliphatic isocyanate is used as a curing agent, and a cured product obtained by curing these with a solvent is preferably used. Is done. Further, a segmented polyurethane elastomer is preferable. For example, a segmented polyurethane elastomer composed of a soft segment mainly composed of a long-chain polyol and a hard segment composed of a diisocyanate, a chain extender and a crosslinking agent is used. Also, for example, a polyurethane foam obtained by reacting a polyisocyanate and a polyol to form a polyurethane and foaming using a chemical reaction is also used (other gas generation methods include a physical foaming method, and thereby Polyurethane foam can also be used).

In the present invention, in order to reproduce wrinkles at the time of suture ligation, a structure in which the skin layer is made of polyurethane elastomer and has a thickness of 0.03 to 0.1 mm is preferable. By making the skin thinner, wrinkles are generated finely, and by increasing the thickness, the unevenness of the wrinkles increases. However, there is little significance in making wrinkles that can be reproduced by making it thinner than 0.03 mm, but on the other hand, it becomes easy to tear, so a problem in strength must be considered. On the other hand, if it is thicker than 0.1 mm, the wrinkle unevenness becomes too large, which is inappropriate.

It is preferable that the dermis layer is made of a thermosetting urethane elastomer and has a thickness of 1 to 5 mm. The dermis layer generally has a thickness of 2 to 4 mm in order to correspond to each part of the human body. A thickness of 1 mm is necessary as a dermis layer for sewing practice, and a thickness of about 5 mm is required as a dermis layer to perform dermis stitching. On the other hand, even if it exceeds 5 mm, it will depart from the actual structure of the skin structure, so the upper limit is 5 mm. For suturing, it is also useful that the subcutaneous layer is made of foamed urethane and has a thickness of 5 to 20 mm. This is because if the thickness is less than 5 mm, the elasticity is insufficient, and if the thickness exceeds 20 mm, the actual condition is deviated.

In order to manufacture such artificial skin for suture practice, a surface layer forming step of forming a liquid skin layer material on a mold by means such as spraying or brushing, and a fluid dermal layer material on the surface of the cured skin layer It is desirable to use a manufacturing method that includes a dermis layer forming step of stacking layers and a subcutaneous layer forming step of stacking a fluid subcutaneous layer material on the surface of the cured dermis layer. By forming the skin layer first, the thickness of the thinnest skin layer can be controlled relatively easily, and the thickness of the layer overlying it can also be easily controlled.

Since the present invention is configured and operates as described above, the artificial skin for stitching practice that the skin surface does not have a sticky feeling like a silicon product and that a realistic surface form can be obtained after stitching. There is an effect that can be provided. In addition, what is said to be sticky, for example, it is not indicated by numericalization, but since it is a sense that it is relatively easy to determine whether there is a sticky feeling, it is sufficiently clear even in subjective evaluation Conceivable. In addition, according to the present invention, since it has a three-layer structure having a dermis layer and a subcutaneous layer of appropriate thicknesses in particular, it is possible to provide an artificial skin for suture practice that facilitates dermis sutures. In order to practice the suture, it is necessary to form a wound on the surface of the artificial skin using a scalpel. However, the artificial skin for the suture practice according to the present invention has no stickiness and is used when a wound is formed by the scalpel. Excellent sensory reproducibility.

Hereinafter, the present invention will be described in more detail with reference to the illustrated embodiment. FIG. 1 shows an example of an artificial skin 10 for practicing sutures according to the present invention. 11 is a soft epidermis layer that is thinly modeled after the epidermis of a hiff, and 12 is a superficial layer that mimics the dermis of a hiff. A soft dermis layer formed to a thickness, and 13 represents a soft subcutaneous layer formed to have a thickness equal to or greater than the intermediate layer, imitating the subcutaneous tissue of Hif.

In this embodiment, the blending ratio of the resin or the like constituting each of the skin layer 11, the dermis layer 12, and the subcutaneous layer 13 is as follows.
Table 1

-Polyurethane elastomer was used for the skin layer.
A mixture containing a polyol as a main component was used as the main component of the dermis layer, and a modified polyisocyanate was used as the curing agent.
A mixture containing polyol and triethanolamine was used as the main agent for the subcutaneous layer, and modified polyisocyanate was used as the curing agent.

Next, the ratio of the coloring agent added to the skin layer 11 and the dermis layer 12 is shown. For the subcutaneous layer, a white or tan color was used for distinction.
Table 2

-White is a commercially available titanium oxide colorant containing 45-55% titanium oxide.
-Yellow is a commercially available iron oxide colorant containing 35-45% iron oxide.
-Red is a commercially available iron oxide colorant containing 40-50% iron oxide and 1-5% silica.
-Black is a commercially available carbon black colorant containing 20-30% carbon black.

<Example 1>
The polyurethane elastomer shown in Table 1 and the colorant shown in Table 2 were mixed to form a skin layer material. Further, 60% of the main agent shown in Table 1 and 40% of the curing agent were mixed, and a dermis layer material was formed using the coloring material shown in Table 2. Further, 80% of the main agent shown in Table 1 and 20% of the curing agent were mixed, and a subcutaneous layer material was formed using a yellowish brown colorant.

<Example 2>
The polyurethane elastomer shown in Table 1 and the colorant shown in Table 2 were mixed to form a skin layer material. Further, 80% of the main agent shown in Table 1 and 20% of the curing agent were mixed, and a dermis layer material was formed using the colorant shown in Table 2. Further, 80% of the main agent shown in Table 1 and 20% of the curing agent were mixed, and a subcutaneous layer material was formed using a yellowish brown colorant.

<Manufacturing method>
1: The artificial skin 10 for suture practice of the present invention having such a configuration is manufactured according to the process shown in FIG. A concave mold 14 made of a material inert to the polyurethane material is prepared. In the present invention, the concave mold 14 is formed using silicon resin, and the skin layer material described in Example 1 is sprayed evenly on the bottom surface of the concave mold 14 using the spray gun 15 (processes A and B). A uniform skin layer 11 having a thickness of 0.05 mm (lower limit) is formed. Next, after the skin layer 11 is cured, the dermis layer material described in Example 1 is stacked on the surface of the skin layer 11 in a layer shape having an equal thickness using an appropriate nozzle (process C). A uniform dermis layer 12 having a thickness of 2 mm (lower limit) is formed, and further, after waiting for the dermis layer 12 to harden, the subcutaneous layer material described in Example 1 is uniformly laminated on the surface (process D). An artificial skin 10 was manufactured by forming a uniform subcutaneous layer 13 having a thickness of 4 mm (lower limit) on the bottom surface. The obtained artificial skin 10 had a sticky feeling with an image color of young skin.

<Manufacturing method>
No. 2: As in No. 1, the concave mold 14 is formed using silicon resin, and the skin layer material described in Example 1 is sprayed evenly using the spray gun 15 on the bottom surface of the concave mold 14 (process A). B), a uniform skin layer 11 having a thickness of 0.08 mm (upper limit) is formed on the bottom surface. Next, after the skin layer 11 is cured, the dermis layer material described in Example 1 is stacked on the surface of the skin layer 11 in the form of a layer having an equal thickness using an appropriate nozzle (process C). A uniform dermis layer 12 having a thickness of 5 mm (upper limit) is formed, and after waiting for the dermis layer 12 to harden, the subcutaneous layer material described in Example 1 is uniformly laminated on the surface (Process D). An artificial skin 10 was manufactured by forming a uniform subcutaneous layer 13 having a thickness of 16 mm (upper limit) on the bottom surface. The obtained artificial skin 10 had a non-sticky feeling with an image color of middle-aged and older skin.

When the artificial skin 10 is manufactured using the concave mold 14 as described above, the planar size is determined by the bottom area of the concave mold 14, and in the case of using another manufacturing method, the artificial skin 10 is formed to have an arbitrary planar size. Will be. Therefore, it is desirable to cut the artificial skin 10 manufactured in consideration of the use situation into an arbitrary planar size and provide it as a plate of a certain size suitable for medical students and the like.

Suture practice using the above artificial skin 10 for suture practice will be described with reference to FIGS. The artificial skin 10 for suture practice of FIG. 2 is formed as a plate of a certain size, and in order to perform the suture practice, first, a wound 16 is formed on the surface of the artificial skin 10 using a scalpel. (FIG. 2A). There is a method called a full-thickness nodule suture that stitches the entire epidermis, dermis, and subcutaneous tissue as the most standard suture performed in the suture of the skin. 2 and 3 illustrate this method. This method is the basis of the nodule suture, and the needle 16 is pierced at right angles to the epidermis layer 11 and moved to wrap up to the subcutaneous layer 13 so that the facing portions of the wound 16 are appropriately aligned. The suture thread 17 is tied on the epidermis (indicated by a knot 17a). As a result of the suturing, wrinkles 18 are generated on the surface of the epidermis layer 11. By observing the form of the wrinkles 18, the suitability of the suturing can be determined.

全 There are vertical mattress stitches and horizontal mattress stitches for all-layer knot stitches. In the vertical mattress suture, the needle is pierced shallowly from one side of the wound surface, and one end of the wound surface is extracted onto the epidermis. Next, from the outside of the extracted site, the needle is again pierced to the subcutaneous layer 13 and the other side. Extract to the epidermis at the outer part. The suture 17 is called in this way because it is sutured at two positions below and below the epidermis and below the subcutaneous tissue. The horizontal mattress stitching punctures the needle from one side of the wound surface to the required layer to some extent, and then punctures the other side of the wound surface and then pulls it out onto the epidermis, and then a suitable distance parallel to the wound direction from the extracted site. From the distant position, the needle is again pierced to the required layer, and extracted from the epidermis at the other site and ligated. As for the vertical and horizontal mattress stitches, the suitability of the stitches can be determined in the same manner as described above. There are various other techniques for suturing, but the present invention is applicable to almost all techniques.

Thread knots, called ligatures, break even if a strong suture is used, if they are pulled suddenly or tied roughly, so it is necessary to tie them with an appropriate force. Also, when pulling away a strained tissue, the tissue may be avoided if the tissue is pulled with the force of a thread. Overtightening of the suture may impede tissue blood flow, impair engraftment (the wound will heal and connect the tissues), and may cause tissue necrosis in some cases. On the other hand, if the suture is too loose, the wound may not be formed.

As described above, ligation is an important technique, and wrinkles that can be formed in the epidermis layer 11 by ligation of the suture thread 17 are useful materials for determining whether or not the technique is complete. That is, if there are few wrinkles 18 in the ligation part of the epidermis layer 11, it can be judged that appropriate sewing is performed, and it is judged that it is improper stitching, so that the wrinkle 18 of a ligation part increases. In addition to the above, there is also a method of continuous suturing using a long suture called continuous suturing, which is applied to unimportant suturing, but even in that case, by observing the wrinkles formed in the epidermis layer 11, The state of the procedure can be determined appropriately.

FIG. 4 shows a dermal suture, where a wound 16 is first opened to apply suture 17 from the subcutaneous tissue in the direction of the dermis, and then the needle is moved from one subcutaneous layer 13 to the dermal layer 12 on one side of the opened wound 16. And sew from the dermis layer 12 to the subcutaneous layer 13 on the opposite side of the wound 16, and then the suture 17 is ligated subcutaneously while tightening the wound 16 to close. Such a procedure is performed over the entire wound 16, and the suture 17 is cut subcutaneously to complete the suture. In the actual procedure, the tape is further bonded to the wound portion formed in the epidermis layer 11 to complete the procedure.

In the present invention, a flexible dermis layer 12 having a thickness equal to or greater than the surface layer imitating the hive dermis and a soft subcutaneous layer 13 having a thickness equal to or greater than the intermediate layer imitating the subcutis of the hiff. Dermal suture can be easily performed. If the procedure is ideally performed, the epidermal layer 11 is closed and the appearance of the wound surface is also beautiful. In the above description, the matter of suturing and ligating a wound formed on a human hiff has already been described. However, it is clear that the present invention can be applied to skin other than human.

It is a partial cross section explanatory drawing which expands and shows an example of the artificial skin for suture practice which concerns on this invention. 1 shows an example of full-layer knot suture performed using the artificial skin for suture practice same as above, wherein A is a plan view at a wound formation stage, and B is a plan view at a suture end stage. FIG. It is a section explanatory view expanding and showing an example of a stitching part of Drawing 2B. It is a partial cross section explanatory drawing which expands and shows an example of a dermis suture performed using the artificial skin for suture practice same as the above. It is explanatory drawing which followed the process A, B, C, D, and showed the manufacturing method of the artificial skin for suture practice which concerns on this invention.

10 Artificial Skin for Suture Practice 11 Epidermis Layer 12 Dermis Layer 13 Subcutaneous Layer 14 Concave 15 Spray Gun 16 Wound 17 Suture 18 Wrinkle

Claims

An artificial skin for carrying a needle using a surgical suture, and suturing and ligating a wound of Hif,
A flexible skin layer that is thinly modeled after the skin of the hiff,
A flexible dermis layer that is thicker than the surface layer, imitating the dermis of Hif,
It has a flexible subcutaneous layer formed to have a thickness equal to or greater than that of the intermediate layer, imitating the subcutaneous tissue of Hif,
An artificial skin for practicing stitching characterized by at least a three-layer structure made of a polyurethane material.
The artificial skin for suture practice having a three-layer structure according to claim 1, wherein the skin layer is made of polyurethane elastomer and has a thickness of 0.03 to 0.1 mm in order to reproduce wrinkles during suture ligation.
The artificial skin for suture practice having a three-layer structure according to claim 1 or 2, wherein the dermis layer is made of a thermosetting urethane elastomer and has a thickness of 1 to 5 mm.
The artificial skin for practicing suture having a three-layer structure according to claim 1 or 2, wherein the subcutaneous layer is made of urethane foam and has a thickness of 5 to 20 mm.
A method for producing the artificial skin according to claim 1,
A surface layer forming step of forming a liquid skin layer material on the mold;
A dermis layer forming step of superimposing a fluid dermis layer material on the surface of the cured epidermis layer;
A method for producing artificial skin for suture practice through a subcutaneous layer forming step of laminating a fluid subcutaneous layer material on the surface of a cured dermis layer.