Shell for artificial joint and method for producing the same

Abstract

To achieve both antibacterial property and control of adhesion to bone.SOLUTION: A shell for an artificial joint comprises: a cup-shaped base having an outer surface that includes a first region and a second region adjacent to the first region; and a coating film including a calcium phosphate material and an antibacterial material, the coating film being arranged so as to straddle the first region and the second region on the outer surface of the base. The surface of the coating film in the first region has greater surface roughness than the surface of the coating film in the second region.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to shells for artificial joints and methods of making the same. [Background technology]

[0002] The use of bioimplants for the treatment of both bone injuries and diseases is constantly expanding with the increase in the active and elderly population. Among them, bioimplants that are coated with antibacterial agents and coatings that adhere to bone are known.

[0003] For example, Patent Document 1 describes a coating for medical implants that contains a bone bonding agent as a part thereof and also contains an antibacterial metal agent that contains silver. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2011-512959 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above-mentioned conventional techniques leave room for improvement in terms of achieving both antibacterial properties and control of adhesion to bone. [Means for solving the problem]

[0006] The present disclosure provides a shell for an artificial joint, comprising a cup-shaped base having an outer surface including a first region and a second region adjacent to the first region, and a coating including a calcium phosphate material and an antibacterial material, the coating having a surface roughness greater in the first region than in the second region.

[0007] In addition, the manufacturing method of an artificial joint shell according to the present disclosure includes a step of preparing a cup-shaped base body, a step of exposing a portion of the outer surface of the base body and arranging a first protective material so as to protect the other portion of the outer surface, a first roughening step of forming a first rough surface portion on the portion exposed from the first protective material, a step of removing the first protective material, and a coating forming step of forming a coating containing a calcium phosphate material and an antibacterial material on the first rough surface portion and at least a portion of the other portion of the outer surface. Effect of the Invention

[0008] According to the invention of the present disclosure, it is possible to provide a shell for an artificial joint that combines control of adhesion to bone with antibacterial properties. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic diagram showing an artificial joint shell according to one embodiment as viewed from above. [Diagram 2] FIG. 2 is a schematic diagram showing an artificial joint shell according to one embodiment as viewed obliquely from below. [Diagram 3] 2 is a schematic diagram showing a cross section of the artificial joint shell according to one embodiment taken along line AA' in FIG. 1.

[0023] FIG. [Figure 4] 4 is a schematic diagram showing an example of a cross section of the shell for an artificial joint according to one embodiment when a region X in FIG. 3 is enlarged. FIG. [Diagram 5] 4 is a schematic diagram showing an example of a cross section of the shell for an artificial joint according to one embodiment when a region X in FIG. 3 is enlarged. FIG. [Figure 6] 4 is a schematic diagram showing an example of a cross section of the shell for an artificial joint according to one embodiment when a region X in FIG. 3 is enlarged. FIG. [Figure 7] 4 is a schematic diagram showing an example of a cross section of the shell for an artificial joint according to one embodiment when a region X in FIG. 3 is enlarged. FIG. [Figure 8] 2 is a schematic diagram showing an example of a cross section of the artificial joint shell according to one embodiment taken along line BB' in FIG. 1. FIG. [Figure 9]9 is a schematic diagram showing an example of a cross section of the artificial joint shell according to one embodiment when a region Y in FIG. 8 is enlarged. FIG. [Figure 10] FIG. 1 is a schematic diagram showing an artificial hip joint according to one embodiment. [Figure 11] FIG. 13 is a schematic diagram showing an example of connecting an instrument to a shell for an artificial hip joint according to one embodiment. [Figure 12] FIG. 13 is a schematic diagram showing an example of connecting an instrument to a shell for an artificial hip joint according to one embodiment. [Figure 13] 1A to 1C are process diagrams showing a method for manufacturing an artificial joint shell according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An embodiment will be described in detail below. In this specification, unless otherwise specified, "A to B" representing a numerical range means "A or more and B or less."

[0011] [1. Shells for artificial joints] First, the configuration of an artificial joint shell 130 according to one embodiment will be described with reference to Figs. 1 to 4. Fig. 2 is a perspective view of the artificial joint shell 130. As shown in Fig. 2, the artificial joint shell 130 has a hemispherical shape, for example, one half of a spherical member, and a coating 20 is disposed on the outer surface of a hemispherical base body 10. The coating 20 includes a calcium phosphate material and an antibacterial material. The calcium phosphate material has the effect of improving adhesion to bone. The antibacterial material has the effect of reducing adhesion and proliferation of bacteria.

[0012] The substrate 10 is a member in which a liner 120, which will be described later, is disposed. The substrate 10 has a cup shape having a recess including an opening 12 that opens in one direction of the substrate 10. As a result, the liner 120 is disposed in the substrate 10 through the opening 12. The substrate 10 according to this embodiment includes a layer member 30 between the outer surface and the coating 20. The substrate 10 also has a screw hole 31 and a countersunk hole 32. In the present invention, the substrate 10 does not necessarily have to have the layer member 30, the screw hole 31, and the countersunk hole 32.

[0013] 2, in this embodiment, the surface of the shell 130 for artificial joints corresponding to a cross section obtained by dividing a sphere so as to include the center of the sphere is defined as the XY plane, and the direction perpendicular to the XY plane toward the apex of the hemisphere is defined as the Z direction. The Z direction is also referred to as the upper side of the shell 130 for artificial joints.

[0014] FIG. 1 is a schematic diagram showing the artificial joint shell 130 as viewed from above. As shown in FIG. 1, the artificial joint shell 130 has a hemispherical shape as described above. The base 10 has a hemispherical shape, and the outer surface of the base 10 has a first surface 301 (lower surface, see FIG. 2) facing downward (negative direction of the Z axis) of the base 10, and a second surface 302 (outer peripheral surface, see FIG. 2) different from the first surface 301. The first surface 301 is a surface that defines the opening 12, and the second surface 302 is a surface that contacts the pelvis during surgery. In this embodiment, the first surface 301 is a flat surface, and the second surface 302 is a convex curved surface.

[0015] The cup shape of the base 10 may be a hemispherical shape formed by dividing the aforementioned spherical member in half, or may be, for example, a spherical cutout shape obtained by cutting out a region smaller than half of a sphere, or the other half of a spherical cutout shape cut out of a sphere. Also, for example, it may be a semi-ellipsoidal shape formed by dividing an ellipsoid so as to include the center, an elliptical cutout shape obtained by cutting out a region smaller than half of an ellipsoid, or the other half of an elliptical cutout shape cut out of an ellipsoid.

[0016] The convex curved surface of the second surface 302 may be convex when the second surface 302 is viewed as a whole, and may have locally concave portions. The convex curved surface of the second surface 302 may be curved when viewed as a whole, and may have locally flat portions. The inner surface of the recess of the base 10 has a concave curved surface. This inner surface may be concave when viewed as a whole, and may have locally convex portions. The concave curved surface of this inner surface may be curved when viewed as a whole, and may have locally flat portions.

[0017] Furthermore, opening 12 when base 10 is viewed from the side may be a straight line as shown in FIG. 3, or may be an upwardly convex curved line or a downwardly convex curved line, or may be wavy having two or more upwardly convex and / or downwardly convex portions.

[0018] The outer surface of the base 10 according to this embodiment includes a first region 1 and a second region 2, and also includes a third region 3. The base 10 according to the present embodiment does not necessarily have to include the third region 3. The base 10 according to this embodiment is provided with the above-mentioned screw hole 31 and countersunk hole 32. In this case, the base 10 may further include a fourth region 4 and a fifth region 5. The base 10 according to the present embodiment may not necessarily have the fourth region 4 and the fifth region 5.

[0019] The first region 1 is a region that is located in at least a part of the outer surface of the base 10, excluding the end of the second surface 302. When the base 10 has the screw hole 31 and the countersunk hole 32, the first region 1 is a region that is located in at least a part of the outer surface of the base 10, excluding the end of the second surface 302, the screw hole 31, and the periphery of the countersunk hole 32.

[0020] The second region 2 is adjacent to the first region 1 and is disposed between the first region 1 and the opening 12 of the base 10. The third region 3 is adjacent to the second region 2 and is disposed between the second region 2 and the opening 12. The fourth region 4 is adjacent to the first region 1 and is disposed between the first region 1 and the screw hole 31 or the countersunk hole 32. The fifth region 5 is adjacent to the fourth region 4 and is disposed between the fourth region 4 and the screw hole 31.

[0021] The coating 20 is disposed so as to straddle the first region 1 and the second region 2 on the outer surface of the substrate 10, and the surface of the coating in the first region 1 has a larger surface roughness than the surface of the coating in the second region 2.

[0022] In addition, the coating 20 located in the second region 2 may have an end 21 and a base 22 located closer to the first region 1 than the end 21, and the thickness of the base 22 may be greater than the thickness of the end 21.

[0023] Furthermore, when the third region 3 is disposed on the substrate 10, the outer surface of the substrate 10 located in the third region 3 is exposed from the coating 20. The surface of the coating 20 in the second region 2 has a larger surface roughness than the outer surface in the third region 3.

[0024] Furthermore, when the fourth region 4 is disposed on the substrate 10, the outer surface located in the fourth region 4 has a smaller surface roughness than the surface of the coating in the first region 1. The coating 20 is disposed on at least a portion of the outer surface in the fourth region 4. When the fifth region 5 is disposed on the substrate 10, the entire outer surface in the fifth region 5 is exposed from the coating 20.

[0025] Fig. 3 is a cross-sectional view of the artificial joint shell 130 taken along the line AA' in Fig. 1. Figs. 4 to 7 are schematic views showing an enlarged state of region X in Fig. 3.

[0026] In the substrate 10, the first region 1 and the second region 2 are located in this order, and when the substrate 10 has the third region 3, the first region 1, the second region 2, and the third region 3 are located in this order as shown in Fig. 4. The first region 1 and the second region 2, or the first region 1, the second region 2, and the third region 3 can be understood to be located in this order in a direction parallel to the surface of the substrate 10. When the substrate 10 does not have the third region, the second region 2 corresponds to the end of the substrate 10 on the opening 12 side, and when the substrate 10 has the third region, the third region 3 corresponds to the end of the substrate 10 on the opening 12 side.

[0027] In addition, in Figs. 4 to 7, the first region 1, the second region 2, and the third region 3 are hatched differently for convenience, but they do not need to be different parts. The substrate 10 may be made of one part. The first region 1, the second region 2, and the third region 3 can be distinguished in design, for example, by the presence or absence of a coating or the presence or absence of a rough surface described later. The coating 20 is located so as to straddle the first region 1 and the second region 2. The third region 3 is exposed from the coating 20. Here, when the substrate 10 has the third region 3, the surface of the coating 20 located in the first region 1 has a larger surface roughness than the surface of the substrate 10 in the third region 3.

[0028] An example of the surface roughness index is the arithmetic mean roughness Sa (ISO 25178). The surface roughness (Sa) of the coating 20 located in the first region 1 may be set to, for example, 10 to 80 μm, 20 to 80 μm, or 30 to 70 μm. The surface roughness (Sa) of the substrate 10 in the third region 3 may be set to, for example, less than 1.0 μm.

[0029] The surface roughness Sa of the first region 1 can be determined from the measurement results of the entire first region 1. Similarly, the surface roughness Sa of the second region 2 can be determined from the measurement results of the entire second region 2, and the surface roughness Sa of the third region 3 can be determined from the measurement results of the entire third region 3. For example, the first region 1 may have a portion where the surface roughness is locally smaller than the surface roughness of the substrate 10 in the second region 2, and the second region 2 may have a portion where the surface roughness is locally larger than the surface roughness of the coating 20 in the first region 1.

[0030] The surface roughness of the coating 20 or the surface roughness of the substrate 10 may be measured, for example, by a stylus or optical method. The surface roughness may be measured, for example, in accordance with "ISO 25178." The method for measuring the surface roughness is not limited to the above method.

[0031] Here, conventionally, there has been room for improvement in artificial joint shells from the viewpoint of achieving both antibacterial properties and control of adhesion to bone. That is, for example, when the surface of the artificial joint shell has a region with high surface roughness, the edge of the region with high surface roughness may irritate bone or soft tissue and become a starting point of bacterial infection.

[0032] In the artificial joint shell 130 according to the present disclosure, the surface roughness of the coating 20 in the first region 1 is greater than that in the second region 2. Therefore, adhesion to bone can be sufficiently ensured. Furthermore, the coating 20 spans the first region 1 and the second region 2. Therefore, the end of the first region can be covered with the coating 20 having antibacterial properties, and the artificial joint shell 130 can achieve both adhesion to bone and control of antibacterial properties.

[0033] The substrate 10 may be made of metal, ceramic, or plastic. Examples of metals include stainless steel alloys, cobalt-chromium alloys, titanium, and titanium alloys. Examples of titanium alloys include alloys in which at least one of aluminum, tin, zirconium, molybdenum, nickel, palladium, tantalum, niobium, vanadium, and platinum is added to titanium. Examples of ceramics include alumina, zirconia, and alumina-zirconia composite ceramics. Examples of plastics include polyethylene, fluorine-based resins, epoxy resins, polyether ether ketone (PEEK) resins, and bakelite. In this embodiment, the substrate 10 is made of a titanium alloy.

[0034] The first region 1 is at least partially covered with the coating 20. That is, the first region 1 may be entirely or partially covered with the coating 20. The surface of the coating 20 located in the first region 1 has a larger surface roughness than the surface of the coating 20 in the second region 2. By providing a region with such a large surface roughness, the adhesion to the bone can be improved. For example, by forming a rough surface in the first region 1 and covering the rough surface with the coating 20, the surface roughness of the coating 20 located in the first region 1 can be increased.

[0035] The surface roughness of the rough surface formed in the first region 1 is set to be larger than that of the second region 2. Therefore, the surface roughness of the coating 20 located in the first region 1 can be made larger than that of the coating 20 located in the second region 2. The surface roughness of the rough surface formed in the first region 1 may be set to, for example, 10 to 80 μm, 20 to 80 μm, or 30 to 70 μm. The surface roughness of the rough surface can be measured, for example, by cutting the shell for artificial joint 130 and observing the cut surface by SEM or the like. The shell for artificial joint 130 according to the present invention is not limited to the case where the surface roughness of the first region 1 is larger than that of the second region 2.

[0036] The artificial joint shell 130 may further include a layer member 30. The layer member 30 may be disposed on the first region 1. As a result, as shown in FIG. 4, the first region 1 is higher than a region (e.g., the second region 2) where the layer member 30 is not provided. Therefore, when the artificial joint shell 130 is embedded in a bone, the first region 1 can be mainly in contact with the bone. In this specification, the "layer member" means a member laminated on the base body 10 and different from the coating 20. For example, the surface of the layer member 30 may be roughened. This allows the region that mainly contacts the bone to be roughened. The layer member 30 may be formed by a thermal spraying method as described later. Alternatively, the layer member 30 may be formed as a porous structure. In this embodiment, the surface roughness of the layer member 3 is set to be larger than the surface roughness of the second region 2.

[0037] The height of the layer member 30 may be set, for example, to a lower limit of 100 μm or more, or may be set to 300 μm or more. The upper limit may be set, for example, to 1000 μm or less, or may be set to 700 μm or less. The surface roughness of the layer member 30 may be set, for example, to 10 to 80 μm, 20 to 80 μm, or 30 to 70 μm.

[0038] Alternatively, the base 10 may have a shape that allows the first region 1 to mainly contact the bone without providing the layer member 30. For example, the first region 1 may have a shape that is raised with respect to the second region 2 and the third region 3.

[0039] The layer member 30 may be made of the same material as that of the base body 10. For example, the layer member 30 may be made of a metal. The layer member 30 and the base body 10 may be made of the same material or different materials. This ensures sufficient strength. In this embodiment, the layer member 30 is made of the same material as that of the base body 10. In this embodiment, the layer member 30 is made of a titanium alloy.

[0040] The layer member 30 may have an edge that is shorter than the inside of the layer member 30. In this specification, the "inside of the layer member" means the inside in the plane direction of the layer member 30. Figure 5 shows a layer member 30 having an edge that is shorter than the inside. This can reduce the concentration of stress on the edge of the layer member 30.

[0041] The coating 20 includes a calcium phosphate-based material and an antibacterial material. The calcium phosphate-based material may be, for example, one or a mixture of two or more selected from the group consisting of hydroxyapatite, α-tricalcium phosphate, β-tricalcium phosphate, quaternary calcium phosphate, octacalcium phosphate, and calcium phosphate-based glass. The antibacterial material may be a natural antibacterial agent, an organic antibacterial agent, or an inorganic antibacterial agent. The natural antibacterial agent may be, for example, hinokitiol, the organic antibacterial agent may be, for example, benzalkonium chloride, and the inorganic antibacterial agent may be a metal, for example, silver, copper, zinc, or the like. In addition to the calcium phosphate-based material and the antibacterial material, the coating 20 may also include glass ceramics and may also include an antibacterial drug such as penicillin or vancomycin.

[0042] The concentration of the antibacterial material in the coating 20 may be, for example, 0.05% to 3.00% by weight, 0.05% to 2.50% by weight, 0.05% to 1.00% by weight, or 0.1% to 1.00% by weight. If the concentration of the antibacterial material is 0.05% by weight or more, sufficient antibacterial properties can be obtained. Also, if the concentration of the antibacterial material is 3.00% by weight or less, the burden on living tissue can be reduced.

[0043] The coating 20 may be disposed on the layer member 30. As described above, the layer member 30 may be in primary contact with bone. The presence of the coating 20 on the layer member 30 can further improve adhesion to bone and antibacterial properties.

[0044] The height of the layer member 30 may be greater than the thickness of the coating 20. This makes the region where the layer member 30 is formed higher than the region where only the coating 20 is formed, allowing the region where the layer member 30 is formed to mainly come into contact with the bone. The thickness of the coating 20 may be set to less than 100 μm, for example, or less than 50 μm. The thickness of the coating 20 may be set to 5 μm or more, for example.

[0045] The second region 2 is at least partially covered by the coating 20. That is, the second region 2 may be entirely covered by the coating 20, or only partially covered by the coating 20. In this specification, the coating 20 "straddles the first region and the second region" means that at least a part of the boundary between the first region 1 and the second region 2 is covered by the coating 20. That is, the boundary between the first region 1 and the second region 2 may be entirely covered by the coating 20, or only a part of the boundary may be covered by the coating 20. When the layer member 30 is disposed in the first region 1, the coating 20 may extend from the first region 1 to the second region 2 so as to cover the edge of the layer member 30. That is, it is possible to prevent the edge of the layer member 30 from being exposed from the coating 20. This can further reduce the proliferation of bacteria.

[0046] The coating 20 located in the second region 2 may have an end 21 and a base 22 located closer to the first region 1 than the end 21. In this specification, the "end of the coating located in the second region" means a region of the coating 20 located in the second region 2 that is closer to the boundary between the second region 2 and the third region 3. Also, the "base of the coating located in the second region" means a region of the coating 20 located in the second region 2 that is closer to the boundary between the first region 1 and the second region 2. Here, the thickness of the base 22 may be greater than the thickness of the end 21. FIG. 6 shows a coating 20 in which the thickness of the base 22 is greater than the thickness of the end 21. This can reduce stress concentration near the boundary between the first region 1 and the second region 2, and as a result, peeling of the coating 20 can be reduced. When the layer member 30 is disposed in the first region 1, stress concentration near the edge of the layer member 30 can be reduced.

[0047] The third region 3 is exposed from the coating 20. The part where the coating 20 is disposed and the part where the coating 20 is exposed can be distinguished by elemental analysis of the surface of each region. The elemental analysis can be performed, for example, by mapping the surface elements using an energy dispersive X-ray analyzer (EDX) that is an auxiliary device of a general scanning electron microscope (SEM). Surface analysis methods such as X-ray photoelectron spectroscopy, Auger electron spectroscopy, and secondary ion mass spectrometry may also be used. The elements may also be confirmed by chemically analyzing the samples obtained by mechanically scraping off the surface of each region. For example, phosphorus, calcium, antibacterial components, etc. are detected on the surface of at least a part of the first region 1 and at least a part of the second region 2 where the coating 20 is disposed. On the surface of the third region 3, elements constituting the substrate 10 are detected, and phosphorus, calcium, antibacterial components, etc. are not detected or are below the noise level.

[0048] The surface of the coating 20 located in the second region 2 may have a smaller surface roughness than the surface of the coating 20 located in the first region 1. Fig. 7 shows an embodiment in which the surface roughness of the coating 20 located in the second region 2 is smaller than the surface roughness of the coating 20 located in the first region 1. This makes it possible to sufficiently ensure adhesion to bone and antibacterial properties in the first region 1. Also, physical irritation to soft tissues in the second region 2 can be reduced.

[0049] The surface roughness (Sa) of the coating 20 located in the first region 1 may be set to, for example, 10 to 80 μm, 20 to 80 μm, or 30 to 70 μm. The surface roughness (Sa) of the coating 20 located in the second region 2 may be set to, for example, 0.1 to 10 μm.

[0050] Furthermore, the surface of the coating 20 located in the second region 2 may have a larger surface roughness than the outer surface of the substrate 10 in the third region 3. FIG. 7 is also a diagram showing an embodiment in which the surface roughness of the coating 20 located in the second region 2 is larger than the surface roughness of the substrate 10 in the third region 3. This improves the adhesion between the coating 20 and the substrate 10 in the second region 2, thereby ensuring sufficient adhesion to bone and antibacterial properties. Furthermore, physical irritation to soft tissues in the third region 3 can be reduced. The surface roughness (Sa) of the substrate 10 in the third region 3 may be set to less than 1 μm, for example.

[0051] 7, the surface roughness of the outer surface of the base 10 in the second region 2 may be made larger than the surface roughness of the outer surface of the base 10 in the third region 3. This improves the adhesion between the coating 20 and the base 10 in the second region 2, thereby reducing peeling of the coating 20. The surface roughness (Sa) of the base 10 in the second region 2 may be set to be 0.1 μm or more and less than 10 μm, and may be set to less than 2.0 μm.

[0052] In this embodiment, the surface roughness of the rough surface of the base 10 in the first region 1 (including the rough surface of the layer member 30 ) is set to be greater than the surface roughness of the base 10 in the third region 3 .

[0053] Fig. 8 is a diagram showing a cross section of the artificial joint shell 130 taken along line B-B' in Fig. 1. Fig. 9 is a schematic diagram showing an enlarged state of region Y in Fig. 8. As shown in Fig. 9, the countersunk hole 32 has a through portion 321 (second through portion) on the outer surface side smaller in width than a through portion 322 (first through portion) on the opening 12 side. That is, the countersunk hole 32 has a through portion 322 and a through portion 321 that is connected to the through portion 322 and the outer surface and has a smaller width than the through portion 322.

[0054] That is, the base 10 may have at least one through hole (screw hole 31, countersunk hole 32) penetrating the outer surface and the inner surface (opening 12 side) of the base 10. At least one of the through holes (screw hole 31) is disposed at a position farther away from the opening 12 than the other position (countersunk hole 32). The other through hole, countersunk hole 32, can be said to have a through portion 322 and a through portion 321 that is connected to through portion 322 and the outer surface and has a narrower width than through portion 322.

[0055] Additionally, the artificial joint shell 130 may be configured to have one or more fins.

[0056] [Screw hole 31 and countersunk hole 32] The screw hole 31 is used, for example, during surgery to connect an instrument to the artificial joint shell 130. For example, as shown in Fig. 11, by fixing the tip of a holder 310 to the screw hole 31 of the artificial joint shell 130, the artificial joint shell 130 can be held by the holder 310 and the artificial joint shell 130 can be moved to a desired position.

[0057] The countersunk hole 32 can be used to fasten the prosthesis shell 130 to the hip bone 93 with a screw 320, as shown in FIG.

[0058] With the above configuration, the shell 130 for artificial joint according to the present disclosure has a rough surface portion, which can further improve bone conduction and bone fixation. Furthermore, since the coating covers the edge of the rough surface portion so that it is not exposed, it is possible to prevent bacteria from growing on the edge of the rough surface portion.

[0059] In addition, the cup-shaped edge, which is susceptible to stress, is not roughened, which reduces physical irritation to soft tissues. Also, the edge of the shell is lowered by one level, which reduces irritation at the edge.

[0060] Furthermore, by making the layered member from metal, sufficient strength can be ensured, and by providing a coating on the layered member, adhesion to bone and antibacterial properties are improved.

[0061] In addition, since the height of the edge of the metal layer is lower than the inside, stress concentration at the edge of the rough surface portion can be prevented.

[0062] Also, peeling off from the edges of the overcoat can be prevented.

[0063] In addition, while the second region 2 ensures sufficient adhesion to bone and antibacterial properties, the surface roughness of the third region 3 is small, so that irritation to soft tissues can be further reduced.

[0064] In addition, by providing the coating on the outer surface of the substrate 10 in the second region, which has a greater surface roughness than the outer surface of the substrate 10 in the third region 3, the adhesion between the coating and the substrate is improved, and the coating is less likely to peel off from the substrate.

[0065] It can also be fixed to a fixture or acetabulum at the desired location.

[0066] When the screw hole 31 and the countersunk hole 32 are arranged in the base 10, the first region 1, the fourth region 4, the screw hole 31 or the countersunk hole 32 are located in this order in the base 10. When the base 10 has the fifth region 5, the first region 1, the fourth region 4, the fifth region 5, and the screw hole 31 are located in this order in the base 10. It can be understood that the first region 1, the fourth region 4, the screw hole 31 or the countersunk hole 32, or the first region 1, the fourth region 4, the fifth region 5, and the screw hole 31 are located in this order in a direction parallel to the surface of the base 10. Therefore, when the base 10 does not have the fifth region 5, the fourth region 4 corresponds to the end of the base 10 on the screw hole 31 and the countersunk hole 32 side. When the base 10 has the fifth region 5, the fifth region 5 corresponds to the end of the base 10 on the screw hole 31 side, and the fourth region 4 corresponds to the end of the base 10 on the countersunk hole 32 side. The fourth region may be entirely or partially covered by the coating 20. The boundary between the first region and the fourth region may not be covered by the coating 20, but may be entirely or partially covered by the coating 20. When the boundary between the first region and the fourth region 4 is covered by the coating 20, if the layer member 30 is disposed in the first region 1, the coating 20 may extend from the first region 1 to the fourth region 4 so as to cover the edge of the layer member 30. That is, the edge of the layer member 30 can be prevented from being exposed from the coating 20. This can further reduce the proliferation of bacteria.

[0067] The fifth region 5 is exposed from the coating 20. The part where the coating 20 is disposed and the part where the coating 20 is exposed can be distinguished by elemental analysis of the surface of each region. The elemental analysis can be performed, for example, by mapping the surface elements using an energy dispersive X-ray analyzer (EDX) that is an auxiliary device of a general scanning electron microscope (SEM). Surface analysis methods such as X-ray photoelectron spectroscopy, Auger electron spectroscopy, and secondary ion mass spectrometry may also be used. The elements may also be confirmed by chemically analyzing a sample obtained by mechanically scraping off the surface of each region. For example, phosphorus, calcium, antibacterial components, etc. are detected on the surface of at least a part of the first region 1 and at least a part of the fourth region 4 where the coating 20 is disposed. On the surface of the fifth region 5, elements constituting the substrate 10 are detected, and phosphorus, calcium, antibacterial components, etc. are not detected or are below the noise level.

[0068] The surface of the coating 20 located in the fourth region 4 may have a smaller surface roughness than the surface of the coating 20 located in the first region 1. This makes it possible to reduce physical irritation to the soft tissue in the fourth region 4.

[0069] The surface roughness (Sa) of the coating 20 located in the fourth region 4 may be set to, for example, 0.1 to 10 μm.

[0070] Furthermore, the surface of the coating 20 located in the fourth region 4 may have a surface roughness greater than that of the outer surface of the base 10 in the fifth region 5. The surface roughness (Sa) of the base 10 in the fifth region 5 may be set to less than 1 μm, for example.

[0071] Furthermore, the surface roughness of the outer surface of the base 10 in the fourth region 4 may be greater than the surface roughness of the outer surface of the base 10 in the third region 3 or the fifth region 5. This improves the adhesion between the coating 20 and the base 10 in the fourth region 4, thereby reducing peeling of the coating 20. The surface roughness (Sa) of the base 10 in the fourth region 4 may be set to be 0.1 μm or more and less than 10 μm, and may be set to less than 2.0 μm.

[0072] 2. Manufacturing method of shell for artificial joint A manufacturing method for an artificial joint shell according to one embodiment includes the steps of preparing a cup-shaped base body, exposing a portion of the outer surface of the base body and arranging a first protective material to protect the remaining portion of the outer surface (S101), forming a first roughening portion on the portion exposed from the first protective material (S102), removing the first protective material (S103), and forming a coating 20 containing a calcium phosphate-based material and an antibacterial material on at least a portion of the first roughening portion and the remaining portion of the outer surface (S108).

[0073] This makes it possible to obtain a shell for an artificial joint, as described above, in which the coating 20 is positioned so as to straddle the first region 1 and the second region 2, and the surface of the coating 20 positioned in the first region 1 has a greater surface roughness than the surface of the base body 10 in the second region 2.

[0074] When the cup-shaped base is made of a metal, for example, it can be formed by molding such as casting, plastic processing, or sintering. After being formed by the molding process, the shape may be further adjusted by removal processing such as cutting, grinding, or electric discharge processing. The screw hole 31 or the countersunk hole 32 may be formed during the molding process, or may be formed during removal processing without being formed during the molding process.

[0075] In the first roughening step, the rough surface can be formed by at least one of a thermal spraying method, an additive manufacturing method, a chemical etching method, and a blasting method. Compared to the blasting method, the thermal spraying method, the additive manufacturing method, and the chemical etching method can increase the surface roughness. As the thermal spraying material and the additive manufacturing material, the materials exemplified as the material of the base body 10 can be used. The layered structure described above may be formed by the thermal spraying method or the additive manufacturing method. As the chemical etching method, an alkali treatment or the like can be used. As the blasting method, a sandblasting or the like can be used. The rough surface can be formed before the coating 20 is formed.

[0076] The coating 20 can be formed by a thermal spraying method such as flame spraying, high velocity flame spraying, plasma spraying, etc. It can also be formed by a physical vapor deposition method or a chemical vapor deposition method such as sputtering, ion plating, ion beam deposition, ion mixing, etc. It can also be formed by a wet coating method such as a sol-gel method.

[0077] A protective material may be used to form the rough surface or coating 20 only in a desired area. For example, a masking tape or a screen may be used as the protective material. Alternatively, a jig that covers the substrate 10 may be used as the protective material. Examples of materials for these protective materials include metal, glass, resin, and composite materials thereof.

[0078] The protective material may or may not be in contact with the substrate 10. If the protective material is not in contact with the substrate 10, the spray material or coating material may wrap around the edge of the protective material and adhere to the area covered by the protective material to some extent. This may result in the formation of a layered member 30 having an edge with a lower height compared to the inside, and / or a coating 20 in which the thickness of the base 22 is greater than the thickness of the end 21, as described above. As the protective material, for example, a masking tape that has adhesiveness and can be attached to the substrate 10, or a jig for covering the substrate 10, which will be described later, may be used.

[0079] When a partition is arranged, the position of the partition can be moved each time the rough surface or coating 20 is formed, thereby forming the rough surface or coating 20 in a specific region. When a jig is used, the region covered by the jig can be changed each time the rough surface or coating 20 is formed, thereby forming the rough surface or coating 20 in a specific region. In this case, for example, by adjusting the positional relationship between the discharge nozzle that discharges the thermal spray material or coating material and the partition, the rough surface or coating 20 can be selectively formed only in a desired region. In this case, the tip of the discharge nozzle may be arranged, for example, in a straight line with the surface of the desired region without a partition. The coating material means a material that constitutes the coating. In the first roughening step, the surface of the first region 1 and the tip of the discharge nozzle may be arranged in a straight line without a partition. In the coating forming step, the surface of the region that straddles the first region 1 and the second region 2 and the tip of the discharge nozzle may be arranged in a straight line without a partition. When the base 10 has a screw hole 31 and / or a countersunk hole 32, the surfaces of the first region 1, the region spanning the second region 2, and the fourth region 4 may be arranged in a straight line with the tip of the discharge nozzle without a partition between them. In addition, when the coating 20 is formed simultaneously on the first region 1 and the second region 2, the tip of the discharge nozzle may be arranged in a straight line with the surface of the first region 1 without a partition between them, taking into account the diffusion of the material. Without being limited thereto, the rough surface or coating 20 may be formed with the base 10, the partition, and the discharge nozzle fixed, or the rough surface or coating 20 may be formed while at least one of them is moved. In addition, the angle of the discharge nozzle may be fixed, or the rough surface or coating 20 may be formed while changing it.

[0080] It is also possible to form the roughened surface or coating 20 only in the desired region without using a protective material. For example, the shape, angle, or position of the discharge nozzle that discharges the thermal spray material or coating material can be adjusted to selectively form the roughened surface or coating 20 only in the desired region. For example, the thermal spray material or coating material may be discharged in a state where the discharge nozzle is positioned above the surface of the desired region. In the first roughening step, the thermal spray material may be discharged in a state where the discharge nozzle is positioned above the surface of the first region 1. In the coating forming step, the coating material may be discharged in a state where the discharge nozzle is positioned above the surface of the region that straddles the first region 1 and the second region 2. In the case where the base 10 has a screw hole 31 and / or a countersunk hole 32, the coating material may be discharged in a state where the discharge nozzle is positioned above the region that straddles the first region 1 and the second region 2 and the surface of the fourth region 4. In this case, the rough surface or coating 20 may be formed while fixing the substrate 10 and changing the position and angle of the discharge nozzle, or the rough surface or coating 20 may be formed while fixing the discharge nozzle and changing the position and angle of the substrate 10. The discharge nozzle may be moved at a constant speed or may be moved at a variable speed. The discharge direction of the spray material or coating material may be at an angle of 90° or less with respect to a vector extending from the tip of the discharge nozzle toward the surface of the substrate 10 or the rough surface that is closest to the tip of the discharge nozzle.

[0081] For example, in the first roughening step, a first protective material may be disposed on the base 10 so as to protect the second region 2 while exposing the first region 1, and a rough surface may be formed in the exposed first region 1. When the base 10 is provided with a screw hole 31 and / or a countersunk hole 32, a first protective material may be disposed so as to protect the second region 2, the fourth region 4, and the fifth region 5 while exposing the first region 1, and a rough surface may be formed in the exposed first region 1.

[0082] Moreover, the manufacturing method according to the present disclosure may further include a step of removing the first protective material after the first roughening step and before the coating forming step.

[0083] In addition, after removing the first protective material, a step of scraping the edge of the rough surface, for example the edge of the layer member 30, may be performed. This makes it possible to avoid the concentration of stress on the edge of the layer member 30 and reduce irritation to biological tissue.

[0084] A first masking tape may be used as the first protective material. In this case, the manufacturing method according to the present disclosure may further include a step of attaching the first masking tape to the second region 2 while exposing the first region 1, before the first roughening step. In addition, when the base 10 has a screw hole 31 and / or a countersunk hole 32, the manufacturing method may further include a step of attaching the first masking tape to the second region 2, the fourth region 4, and the fifth region 5 while exposing the first region 1.

[0085] The manufacturing method according to the present disclosure may further include, after the step of removing the first protective material and before the step of forming the coating, a step (S104) of arranging a second protective material so as to expose a part of the other part of the outer surface and protect the other part of the other part of the outer surface, and a second roughening step (S105) of forming a second rough surface portion on at least a part of the other part of the outer surface, and the second rough surface portion may be formed on the part exposed from the second protective material. Also, after the second roughening step, a step (S106) of removing the second protective material may be included.

[0086] In the second roughening step, the rough surface may be formed by at least one of a chemical etching method and a blasting method. The second roughening step may be performed so that the surface of the second rough surface portion formed in the second roughening step has a smaller surface roughness than the surface of the first rough surface portion in the first region 1. When the second rough surface portion is formed, the rough surface in the first region 1 may also be called the first rough surface portion.

[0087] A second masking tape may be used as the second protective material. In this case, the manufacturing method according to the present disclosure may further include, before the second roughening step, a step of attaching a second masking tape to the third region 3 while exposing the first region 1 and the second region 2. In addition, when the base 10 has a screw hole 31 and / or a countersunk hole 32, the manufacturing method may further include a step of attaching a masking tape to the third region 3 and the fifth region 5 while exposing the first region 1 and the fourth region 4.

[0088] The manufacturing method according to the present disclosure may further include a step (S107) of exposing the first rough surface portion and a part of the second rough surface portion and arranging a third protective material to protect the other part of the second rough surface portion and the outer surface after the step of removing the second protective material and before the coating forming step. In this way, in the coating forming step, the coating can be formed on the first rough surface portion and the part of the second rough surface portion exposed from the third protective material. When the base body 10 has a screw hole 31 and / or a countersunk hole 32, the manufacturing method according to the present disclosure may further include a step (S107) of exposing a part of the second rough surface portion and the fourth region 4 and arranging a third protective material to protect the other part of the second rough surface portion, the fifth region 5, and the outer surface. In this way, in the coating forming step, the coating can be formed on the first rough surface portion, the part of the second rough surface portion, and the fourth region 4 exposed from the third protective material.

[0089] A third masking tape may be used as the third protective material. In this case, the manufacturing method according to the present disclosure may further include a step of attaching a third masking tape to another part of the second region 2 while exposing the first region 1 and a part of the second region 2, before the coating formation step. When the base 10 has a screw hole 31 and / or a countersunk hole 32, the method may further include a step of attaching a masking tape to another part of the second region 2 and the fifth region 5 while exposing the first region 1, a part of the second region 2, and the fourth region.

[0090] Moreover, the manufacturing method according to the present disclosure may include a hole forming step of forming holes in the base in the step of preparing the base.

[0091] In the second roughening step, the first region 1 may or may not be covered by a protective material. The first region 1 may be protected, and at least one of the processing by the chemical etching method and the processing by the blasting method may be performed only on the second region 2. When the base 10 has the screw hole 31 and / or the countersunk hole 32, at least one of the processing by the chemical etching method and the processing by the blasting method may be performed on the second region 2 and the fourth region. Alternatively, a second protective material may be disposed so as to expose the first region 1, and at least one of the processing by the chemical etching method and the processing by the blasting method may be performed on the exposed rough surface of the first region 1 and the second region 2. When the base 10 has the screw hole 31 and / or the countersunk hole 32, at least one of the processing by the chemical etching method and the processing by the blasting method may be performed on the rough surface of the first region 1, the second region 2, and the fourth region. This allows excess sprayed material remaining on the rough surface of the first region 1 to be removed, and also allows a rough surface to be formed in the second region 2. If the base 10 has a screw hole 31 and / or a countersunk hole 32, a rough surface can also be formed in the second region 2 and the fourth region.

[0092] It is also possible to form the second rough surface portion only in the desired region without using a protective material. For example, the shape, angle, or position of the discharge nozzle that discharges the chemical etching material or blasting material can be adjusted to selectively form the second rough surface portion only in the desired region. The chemical etching material means a material that is discharged toward the base 10 when processing is performed by the chemical etching method. Similarly, the blasting material means a material that is discharged toward the base 10 when processing is performed by the blasting method. For example, the chemical etching material or blasting material may be discharged in a state where the discharge nozzle is positioned above the surface of the desired region. When the second rough surface portion is formed only in the second region 2, the chemical etching material or blasting material may be discharged in a state where the discharge nozzle is positioned above the surface of the second region 2. When the second rough surface portion is formed in the first region 1 and the second region 2, the chemical etching material or blasting material may be discharged in a state where the discharge nozzle is positioned above the surfaces of the first region 1 and the second region 2. In the case where the base 10 is provided with a screw hole 31 and / or a countersunk hole 32, and the second rough surface portion is formed in the first region 1, the second region 2, and the fourth region 4, the chemical etching material or the blasting material may be discharged with the discharge nozzle positioned above the surfaces of the first region 1, the second region 2, and the fourth region 4. In this case, the base 10 may be fixed and the second rough surface portion may be formed while moving the position and angle of the discharge nozzle, or the discharge nozzle may be fixed and the second rough surface portion may be formed while moving the position and angle of the base 10. The discharge nozzle may be moved at a constant speed or may be moved at a variable speed. In addition, the discharge direction of the chemical etching material or the blasting material may be at an angle of 90° or less than 90° with a vector extending from the tip of the discharge nozzle toward the surface of the base 10 or the rough surface that is the shortest distance from the tip of the discharge nozzle.

[0093] For example, the first roughening step and the coating forming step may use a thermal spraying method, and the second roughening step may use a blasting method. In this case, the first protective material may have a higher heat resistance than the second protective material. The first protective material may have a higher heat resistance than the third protective material. The third protective material may have a higher heat resistance than the second protective material. In order to satisfy such a relationship, for example, a material that does not melt or pyrolyze for 1 minute under thermal spraying conditions of 8000°C may be used as the first protective material, a material that does not melt or pyrolyze for 1 minute under thermal spraying conditions of 3000°C may be used as the third protective material, and a material that does not melt or pyrolyze at room temperature may be used as the second protective material. Specifically, such materials may be a composite material of glass and resin as the first protective material, a composite material of glass and resin as the third protective material, and a resin as the second protective material.

[0094] When a jig that covers the base body 10 is used as the protective material, the shape of the jig is not particularly limited, but may be, for example, cylindrical. The cross section of the cylindrical jig may be polygonal or circular.

[0095] To sum up the above, each step can be performed in the order shown in Fig. 13, for example. Fig. 13 is a process diagram showing a method for manufacturing an artificial joint shell according to one embodiment. First, a first protective material is placed, then a first surface roughening step is performed, and then the first protective material can be removed. Then, a second protective material is placed, then a second surface roughening step is performed, and then the second protective material can be removed. Then, a third protective material is placed, and then a coating formation step is performed.

[0096] Furthermore, the manufacturing method according to the present disclosure may or may not include a cleaning step between each step. For example, the manufacturing method according to the present disclosure may include a step of cleaning the substrate 10, or the substrate 10 and the layered member 30 disposed on the first region 1, after the first roughening step. Also, the manufacturing method according to the present disclosure may further include a step of cleaning the substrate 10, or the substrate 10 and the layered member 30 disposed on the first region 1, after the second roughening step. The cleaning method is not particularly limited, and may be, for example, a method of immersing in a liquid such as water or an organic solvent such as alcohol, or showering using the liquid. Alternatively, it may be a method of blowing a gas such as air, nitrogen, or argon. This makes it possible to remove excess spray material generated by the first roughening step and / or shavings generated by the second roughening step.

[0097] [3. Use of shells for artificial joints] 1 has a shape mainly intended for use as a shell for an artificial hip joint, but the artificial joint to which the artificial joint shell according to the present disclosure is applied is not limited to an artificial hip joint. Examples of artificial joints include an artificial hip joint, an artificial shoulder joint, and an artificial elbow joint.

[0098] An example of using the artificial joint shell 130 as a part of an artificial hip joint 1000 will be described below with reference to FIG. 10. The artificial hip joint 1000 may include an artificial joint stem 100, a femoral head 110, and a liner 120 in addition to the artificial joint shell 130. The artificial joint stem 100 and the femoral head 110 may be made of the same material as the base body 10 of the artificial joint shell 130, or may be made of a different material. The artificial joint stem 100 is embedded in the femur 91. The femoral head 110 is placed in the exposed part of the artificial joint stem 100. The artificial joint shell 130 is fixed to the acetabulum 94 of the hip bone 93, and functions as a hip joint by fitting and sliding the femoral head 110 into a recess in the artificial joint shell 130. More precisely, the femoral head 110 is fitted and slid into a recess in a liner 120 fitted into the opening 12 of the artificial joint shell 130, thereby functioning as a hip joint.

[0099] The invention according to the present disclosure has been described above based on the drawings and examples. However, the invention according to the present disclosure is not limited to the above-mentioned embodiments. In other words, the invention according to the present disclosure can be modified in various ways within the scope of the present disclosure, and the embodiments obtained by appropriately combining the technical means disclosed in the different embodiments are also included in the technical scope of the invention according to the present disclosure. In other words, it should be noted that a person skilled in the art can easily make various modifications or corrections based on the present disclosure. It should also be noted that these modifications or corrections are included in the scope of the present disclosure. [Explanation of symbols]

[0100] 1 1st area 2 Second area 3 Third area 4 4th area 5 5th area 10 Base 20 Coating 21 Edge of the coating 22 Base of the capsule 30 Layered Members 100 Artificial joint stem 110 femoral head 120 Liner 130 Artificial joint shells 1000 Artificial Hip Joint

Claims

1. a cup-shaped substrate having an outer surface including a first region and a second region adjacent to the first region; a coating including a calcium phosphate-based material and an antibacterial material, the coating being disposed across the first region and the second region of the outer surface of the substrate; the surface of the coating in the first region has a greater surface roughness than the surface of the coating in the second region; the second region is disposed between the first region and the opening of the base, the exterior surface of the substrate further includes a third region adjacent to the second region and located between the second region and the opening; the outer surface of the substrate located in the third region is exposed from the coating; An artificial joint shell, wherein at least a portion of the third region of the artificial joint shell having the base body is embedded and fixed in the acetabulum of the hip bone of a human body.

2. The artificial joint shell according to claim 1 , wherein the base body further comprises a layer member disposed in the first region.

3. The artificial joint shell of claim 2 , wherein the layered member is made of metal.

4. The artificial joint shell according to claim 2 or 3, wherein the coating disposed in the first region is disposed on the layer member.

5. 5. The shell for an artificial joint according to claim 2, wherein the layer member has a thickness on the side of the third region that is thinner than the other portions.

6. the coating located in the second region has an end portion and a base portion located closer to the first region than the end portion, The shell for an artificial joint according to any one of claims 1 to 5, wherein the thickness of said base portion is greater than the thickness of said end portion.

7. The artificial joint shell according to any one of claims 1 to 6, wherein the surface of said coating in said second region has a greater surface roughness than the outer surface in said third region.

8. The shell for an artificial joint according to any one of claims 1 to 7, wherein the outer surface in the first region has a greater surface roughness than the outer surface in the second region.

9. The shell for an artificial joint according to any one of claims 1 to 8, wherein the outer surface in the second region has a greater surface roughness than the outer surface in the third region.

10. 10. The artificial joint shell according to claim 1, wherein said base body has at least one through hole passing through said outer surface of said base body and said inner surface of said base body.

11. a cup-shaped substrate having an outer surface including a first region and a second region adjacent to the first region; a coating including a calcium phosphate-based material and an antibacterial material, the coating being disposed across the first region and the second region of the outer surface of the substrate; the surface of the coating in the first region has a greater surface roughness than the surface of the coating in the second region; the second region is disposed between the first region and the opening of the base, the substrate has at least one through hole extending through the outer surface and the inner surface of the substrate; the outer surface of the substrate further includes a fourth region adjacent to the first region and located between the first region and the through hole; A shell for an artificial joint, wherein the outer surface located in the fourth region has a surface roughness smaller than that of the surface of the coating in the first region.

12. At least one of the through holes is disposed at a position farther from the opening than the other through holes, and is a screw hole; The artificial joint shell of claim 11, wherein at least one of the other through holes is a countersunk hole having a first through portion and a second through portion connected to the first through portion and the outer surface and narrower than the first through portion.

13. The artificial joint shell according to claim 12, wherein the coating is disposed on at least a portion of the outer surface of the fourth region.

14. the outer surface of the base further includes a fifth region adjacent to the fourth region and located between the fourth region and the screw hole; The artificial joint shell according to claim 13 or 13, wherein the outer surface of the fifth region is entirely exposed from the coating.

15. The prosthetic shell of claim 12 , wherein the fourth region is adjacent the counterbore.

16. Providing a cup-shaped substrate; disposing a first protective material so as to expose a portion of an outer surface of the substrate and protect another portion of the outer surface; a first roughening step of forming a first rough surface portion on a portion exposed from the first protective material; removing the first protective material; a coating forming step of forming a coating containing a calcium phosphate-based material and an antibacterial material on the first rough surface portion and a part of the other portion of the outer surface, A method for manufacturing a shell for an artificial joint, wherein at least a portion of the other portion of the artificial joint shell having the base body, where the coating is not formed, is embedded and fixed in the acetabulum of the hip bone of a human body.

17. After the step of removing the first protective material and before the step of forming the coating film, The method for producing an artificial joint shell according to claim 16, further comprising a second roughening step of forming a second rough surface portion on at least a part of said other portion of said outer surface.

18. After the step of removing the first protective material and before the second roughening step, The method further includes a step of disposing a second protective material so as to expose a portion of the other portion of the outer surface and protect the other portion of the other portion of the outer surface, 18. The method for producing an artificial joint shell according to claim 17, wherein in the second roughening step, a second rough surface portion is formed on the portion exposed from the second protective material.

19. After the second roughening step and before the coating step, removing the second protective material; A method for producing a shell for an artificial joint according to claim 18.

20. After the step of removing the second protective material and before the step of forming the coating film, The method further includes a step of arranging a third protective material so as to expose the first rough surface portion and a portion of the second rough surface portion and protect the other portion of the second rough surface portion and the outer surface, 20. The method for producing an artificial joint shell according to claim 19, wherein in the coating forming step, the coating is formed on a portion of the first rough surface portion and the second rough surface portion exposed from the third protective material.

21. In the step of arranging the second protective material, the second protective material is arranged so that the first rough surface portion is exposed; A method for manufacturing an artificial joint shell according to any one of claims 18 to 20, wherein in the second roughening step, the first rough surface portion exposed from the second protective material is processed by a blasting method.

22. The method for manufacturing an artificial joint shell according to any one of claims 18 to 21, wherein the first protective material has a higher heat resistance than the second protective material.

23. After the step of removing the second protective material and before the step of forming the coating film, and arranging a third protective material so as to expose the first rough surface portion and a part of the second rough surface portion and to protect the other part of the second rough surface portion and the outer surface, The method for manufacturing an artificial joint shell according to any one of claims 20 to 22, wherein the first protective material has a higher heat resistance than the third protective material.

24. After the step of removing the second protective material and before the step of forming the coating film, and arranging a third protective material so as to expose the first rough surface portion and a part of the second rough surface portion and to protect the other part of the second rough surface portion and the outer surface, The method for manufacturing an artificial joint shell according to any one of claims 20 to 23, wherein the third protective material has a higher heat resistance than the second protective material.

25. A first masking tape is used as the first protective material, A method for manufacturing an artificial joint shell as described in any one of claims 18 to 24, wherein the step of placing the first protective material further includes a step of attaching the first masking tape to other parts of the outer surface so as to expose a portion of the outer surface.

26. A second masking tape is used as the second protective material, A method for manufacturing an artificial joint shell according to any one of claims 18 to 25, further comprising the step of attaching the second masking tape to another part of the other part of the outer surface so as to expose a part of the other part of the outer surface in the step of arranging the second protective material.

27. After the step of removing the second protective material and before the step of forming the coating film, and arranging a third protective material so as to expose the first rough surface portion and a part of the second rough surface portion and to protect the other part of the second rough surface portion and the outer surface, A third masking tape is used as the third protective material, A method for manufacturing an artificial joint shell according to any one of claims 20 to 26, further comprising the step of attaching the third masking tape to other parts of the second rough surface portion and the outer surface so as to expose a portion of the second rough surface portion in the step of placing the third protective material.

28. The method for producing an artificial joint shell according to any one of claims 18 to 27, wherein the step of preparing a base body includes a hole forming step of forming a hole in the base body.

29. After the step of removing the first protective material and before the step of forming the coating, a step of disposing a second protective material so as to expose a part of the other portion of the outer surface and to protect another part of the other portion of the outer surface; a second roughening step of forming a second rough surface portion on the portion exposed from the second protective material; and a step of arranging a third protective material so as to expose the first rough surface portion and a portion of the second rough surface portion and to protect the other portion of the second rough surface portion and the outer surface, In the first roughening step, an edge of the hole is protected by the first protective material, and in the second roughening step, an edge of the hole is exposed from the second protective material; 29. The method for manufacturing an artificial joint shell according to claim 28, wherein in the coating forming step, the edge of the hole is exposed from the third protective material.

30. 30. The method for producing an artificial joint shell according to claim 17, wherein the first surface roughening step is carried out by at least one of a thermal spraying method and a blasting method.

31. The method for producing an artificial joint shell according to any one of claims 17 to 30, wherein the second roughening step is carried out by a blasting method.

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