COATING OF A STRUCTURED IMPLANT SURFACE

Description

TECHNICAL FIELD

[0001] The present invention relates to an antimicrobial implant component with a coated surface structure and to a method for coating such an implant component provided with a surface structure with an antimicrobial coating. BACKGROUND OF THE INVENTION

[0002] The implant surface plays a crucial role in the integration of an implant component into the anatomical environment of a patient's implantation site. For this reason, many attempts are being made to prepare or modify the implant surface so that an implant component can successfully fulfill its function.

[0003] One possible goal for selecting a specific implant surface might be, for example, that the implant surface promotes the ingrowth of bone or soft tissue at the implantation site. In particular, there are a variety of approaches to influencing the properties of the implant surface. These include, for example, the selection of the material from which the implant surface is made or the creation of the surface structure that comes into contact with the tissue after implantation.

[0004] One approach to creating an implant surface involves providing the material of the implant body with a defined surface structure, for example, to increase the implant surface and thus the contact area with the surrounding tissue. To achieve this, the implant surface itself is structured or additional material is applied. An implant surface created in this way can promote tissue ingrowth and thus the integration of an implant component.

[0005] In addition to creating a surface structure, an implant surface can be modified by applying a coating to enhance its functionality and support the specific treatment goal. However, if the implant surface to be coated is structured, challenges still arise for the coating process. These include, for example, the homogeneity or uniform thickness of the coating. These challenges are caused in particular by edges, peaks, and undercuts in the surface structure.

[0006] From document EP 1 093 384 B1, orthopaedic implants are known which have a biocompatible composite coating which adapts to gaps and undercuts and promotes tissue ingrowth.

[0007] WO 2019 / 214992 A1 discloses a coating for an implant component, in particular a component of a spinal implant, comprising a ceramic titanium nitride coating containing, in addition to an at% Ti and an at% N content, an at% Ag content of 5-30 at%. Due to its resistance, the ceramic titanium nitride coating with a silver content, i.e., titanium nitride-silver coating, is particularly suitable for structural implants that support or replace parts of the skeleton once they have been inserted into a patient's body. This includes, for example, an implant component of a joint implant, a spinal implant, or even a bone implant that replaces at least part of a bone. SUMMARY OF THE INVENTION

[0008] Thus, it was an object of the present disclosure to provide an implant component with a surface structure, wherein the surface structure has undercuts and the surface structure, including the undercuts, is coated with a coating. Furthermore, it was an object of the present disclosure to provide a technical method for producing a coating on this surface structure. A further object was that the coating produced by the method be formed as continuously and homogeneously as possible on the surface and have an antimicrobial effect.

[0009] The claimed invention, as a result of one or more of the objects arising from the prior art, is defined by the appended independent claims. The associated dependent claims further define preferred embodiments.

[0010] In particular, the inventors of the claimed subject matter were confronted with the observation that an antimicrobial effect of coatings on implants with a surface structure but without undercuts is at least not necessarily transferable to a surface structure with undercuts. In particular, it was found that the antimicrobial coating essentially loses the intended effect.

[0011] To counteract this, an implant component is disclosed which has a solid material region and a surface structure connected to the solid material region. A coating is provided on the surface structure which, in addition to an at% Ti content as the main component, has at least one further coating component, wherein the at least one further coating component has silver (Ag) with an at% content of 15-25 at% and an at% Nb content, wherein Ag is arranged predominantly in the form of silver agglomerates next to a lattice of the remaining coating components and is not or only slightly interstitially in the lattice. The surface structure has undercuts which are coated with this coating.

[0012] Experiments conducted by the inventors have shown that the application of a commonly used antimicrobial coating to an implant component with a surface structure does not lead to the desired reduction in pathogens. It is suspected that undercuts in the surface structure, in particular, contribute to this effect by impairing the effectiveness of the antimicrobial coating.

[0013] Despite this experience, further tests surprisingly demonstrated that a silver content within the above-defined range leads to an antimicrobial effect. It is suspected that this may be due to an increased effect of the coating in the area of ​​the undercuts. In other words, the coating defined above presumably ensures that the antimicrobial effect is achieved at least over a larger portion of the implant component's surface area, which is enlarged by the surface structure, particularly in the undercuts.

[0014] The coating for the surface structure features titanium as its main component, as this material has proven particularly effective for bone tissue ingrowth. Depending on the application, titanium can be supplemented with other coating components in addition to silver.

[0015] It was found that, with the at% content of silver, a silver content sufficient for an antimicrobial effect is present not only on the areas visible in plan view, but also on the areas of the surface structure hidden in plan view, i.e. the undercuts.

[0016] An undercut is an area of ​​the surface structure that is hidden from view when looking at an implant component because it is located behind the visible part of the surface structure. An undercut can be caused, for example, by an angled recess or an angled protrusion.

[0017] Such undercuts are formed by creating a surface structure on the solid material area of ​​the implant component. This can be achieved by modifying the solid material by removing material from its surface. Additionally, and preferably alternatively, the surface structure is created on top of the solid material. In other words, material is applied to the surface to create a surface structure.

[0018] The surface structure, with its enlarged surface area, is designed specifically for the ingrowth of bone tissue. This is particularly advantageous for implant components that are to be integrated into the bone tissue to form a strong bond with the bone tissue at an implantation site. For example, such a bond is advantageous for joint implants, joint fusions, or bone replacement parts.

[0019] Preferably, the undercuts of the surface structure are formed at least partially by an open-pore structure.

[0020] In other words, the surface structure bonded to the solid material is porous. The surface structure thus features pores that are open and interconnected. Accordingly, bone tissue is able to grow into this open-pore structure. The pores can thus complement each other to form cavities or connecting channels.

[0021] Such a structure, on the one hand, resembles a cancellous bone structure to a certain extent and promotes bone ingrowth. On the other hand, it has the advantage of serving as a kind of interface between the typically very stiff solid material of the implant component and the relatively much softer bone tissue. The surface structure thus exhibits a structurally lower stiffness than the solid material of the implant component. This can also lead to improved integration of the implant component, especially in the long term.

[0022] Regarding the mechanical resistance of the coating, the silver content reduces its hardness but increases its ductility. This is particularly advantageous for a coated porous surface structure, since, as described above, this is softer and can more easily undergo elastic and / or plastic deformation, especially during implantation. Due to its ductility, the coating can at least adapt better to such deformation.

[0023] In addition, the coating prevents the solid material of the implant component from coming into contact with a patient's body tissue, which could potentially lead to hypersensitivity. This is particularly the case if the surface structure is machined or if an applied surface structure does not completely cover the solid material of the implant component. In this case, the coating in this area ensures that surrounding tissue does not come into contact with the solid material.

[0024] One way to create an open-pore surface structure is through the use of a plasma spray coating, particularly a titanium plasma spray coating. The use of a titanium plasma spray coating has the additional advantage that the coating can form a more durable bond to the surface structure created in this way.

[0025] The open-pore structure may additionally or alternatively comprise substantially regularly arranged unit cells, wherein the unit cells are preferably formed by tetrapod-like basic elements.

[0026] Due to the regularity of this open-pore structure, the stiffness and pore size or pore width of the surface structure can be precisely defined in advance. Accordingly, advantages can be realized both for bone ingrowth and in terms of stiffness behavior. Unit cells formed by tetrapod-like basic elements have proven particularly suitable for this purpose.

[0027] Preferably, the open-pore structure has a porosity of 10 to 80% and / or a pore width of 45 to 1000 µm.

[0028] These properties apply particularly to an uncoated, open-pore structure. They promote the coating of the pore interior surfaces, and thus also of the undercuts, with a sufficiently high silver content. In other words, the penetration of silver ions into the surface structure is supported during the coating process. These values ​​also apply to surface structures that are not necessarily porous but have depressions that form undercuts.

[0029] Depending on its aforementioned configuration, a pore in an open-pore structure can have essentially uniform pores of equal size and / or less uniform pores of varying size. In the latter case, the pore width refers to the widest cross-section. The ratio between the widest and narrowest cross-section of a pore is preferably a maximum of 4:1 or 2:1. Generally, a ratio of approximately 1 is considered particularly advantageous.

[0030] Preferably, the surface structure is formed on the solid material with a thickness of up to 4 mm, 3 mm, 2.5 mm, 2 mm, 1.5 mm, 1 mm or 0.5 mm.

[0031] This ensures sufficiently firm integration of the implant component into the bone tissue and good supply of the bone tissue.

[0032] In particular, the silver content of the coating is at least 18 at%, 20 at% or 22 at% and at most 23 at%, 24 at% or 25 at%.

[0033] In these areas, the silver content in the coating is high enough so that the surface structure of the implant component exhibits an antimicrobial effect.

[0034] The coating has an at% proportion of Nb and optionally an at% proportion of N as a further coating component.

[0035] The use of Nb and optionally N as coating components allows for adaptation of the coating properties.

[0036] In combination with the silver component, this not only results in an antimicrobial effect, but also allows the properties of the coating to be adjusted by including one or both of these coating components. Furthermore, these coating components prevent allergic reactions in patients to the material of the solid portion of the implant component.

[0037] Regardless of the coating components used, the coating is preferably essentially a stoichiometric coating. Such a coating, together with the silver component, forms a particularly uniform, inert layer with antimicrobial effects, thus preventing both hypersensitivity and infection after implantation.

[0038] In particular, nitride coatings can be used to improve the wear properties of implant components. Therefore, they are used, for example, for the running surfaces of joint implants, but also on other surfaces exposed to frictional forces, such as fasteners, clamping surfaces, or implant surfaces that are subject to relative movement in contact with another implant component or bone tissue, especially during implantation.

[0039] By adding an at% Nb to the main component Ti and an at% Ag, a titanium-niobium coating with a silver content can be produced (TiNb-Ag).

[0040] The titanium-niobium coating, similar to titanium, exhibits a high degree of biocompatibility. In particular, the coating has a low degree of hardness and is more ductile than a TiN coating. Consequently, it can adapt better to the elastic and plastic deformations that occur during implant use than the TiN-Ag coating. Like the TiN-Ag coating, it also effectively protects against the occurrence of hypersensitivity in the surrounding tissue.

[0041] Furthermore, it is possible to produce a titanium nitride-niobium coating with a silver component (TiNbN-Ag) in addition to the main component Ti and the at% content Ag by providing an at% content N and an at% content Nb.

[0042] Such a coating is both abrasion-resistant and ductile enough to withstand elastic and even minor plastic deformations, such as those that occur during the adjustment of bone plates or spinal fusion rods. Its properties thus lie essentially between those of a TiN-Ag coating and a TiNb-Ag coating.

[0043] Furthermore, it is possible to combine the above coating types to adjust the properties of the coating.

[0044] Particularly preferably, the coating of the implant component is a PVD coating. This means that the coating is applied by means of physical vapor deposition. Through vapor deposition, the ionized coating components reach any undercuts or pores in the surface structure particularly effectively.

[0045] In the above coatings, the at% silver content in the coating is preferably present in island-like manner.

[0046] With regard to the coating mentioned above, for example, this means that Ag islands are surrounded by Ti, TiN, TiNb and / or TiNbN.

[0047] This allows the Ag component to exert its anti-infective effect particularly effectively. To achieve this adjacent coating structure on the surface and thus direct contact with the patient's tissue or fluids, the coating components are applied simultaneously for at least part of the coating process. This simultaneous application of the coating components also ensures that the coating components are distributed essentially evenly across the implant surface.

[0048] Particularly preferably, the coating has a thickness of 1-6 pm, 2.5-6 µm or 3.5-5.5 µm.

[0049] In these areas, a stable, continuous and resilient coating can be achieved on the surface structure and the solid material of the implant component that may be exposed beneath the surface structure, as described above.

[0050] A thicker coating tends to be advantageous. However, a thickness exceeding the values ​​specified above does not provide any significant advantages and can even promote inhomogeneity and delamination of the coating. It is suspected that the mechanical resistance of the coating at the specified thicknesses is also due to the fact that no continuous silver sections are formed in the thickness direction. In other words, the three-dimensional heterogeneous structure of the silver-containing titanium coating essentially creates a continuous coating of titanium or titanium compound.

[0051] Furthermore, the present disclosure relates to a method for applying a coating to an implant component, wherein the method comprises the following steps. First, an implant component, in particular an implant component according to one of the preceding claims, is provided, wherein the implant component is formed with a solid material region and a surface structure connected to the solid material region, and the surface structure has undercuts. The implant component is introduced into a coating chamber. Furthermore, for applying the coating, at least one target made of a metallic material is provided, which target has at least one of the coating components. Before the coating process begins, the coating chamber is closed and locked, and an atmosphere with a pressure of 0.001 to 0.01 mbar is provided.The atmosphere may include a coating component. After the atmosphere is provided, an arc is ignited to vaporize the metallic material of the at least one target and to coat the surface structure (and possibly an exposed area of ​​the solid material beneath the surface structure) with the vaporized metallic material of the at least one target.

[0052] This process enables simultaneous and, above all, continuous coating of the surface structure within the coating chamber. Simultaneous coating and the silver content ensure that silver is exposed to the surface of the coating, allowing the anti-infective effect of the coating to develop. This also applies to any undercuts or pores. Furthermore, by selecting the number of targets of the respective coating components, the at% content can be adjusted, at least in terms of magnitude, to the desired composition of the coating.

[0053] Alternatively or in addition to adjusting the composition of the coating via the number of respective targets, at least one target can be provided that has a predetermined ratio of at least two coating components. In particular, the at least one target comprises silver, titanium, and / or niobium.

[0054] As an alternative to the pressure range above, the atmospheric pressure for the coating process can also be set to a pressure range of 0.003 mbar or 0.005 mbar to 0.1 mbar, 0.05 mbar, 0.02 mbar, 0.015 mbar, or 0.01 mbar. The higher pressure range has the advantage that the coating components can better reach the undercuts or pores, thus ensuring a higher and more uniform coating thickness.

[0055] Furthermore, in the context of providing the implant component, the surface structure can be formed by fused particles which are applied to the solid material of the implant component by means of a plasma spray process, in particular by means of a titanium plasma spray process.

[0056] Such a surface structure promotes the ingrowth of bone tissue through its undercuts and / or porosity and thus ensures stable integration of the implant component.

[0057] Particularly preferably, the surface structure is constructed from unit cells and is preferably formed by means of a layer melting process, in particular an electron beam layer melting process.

[0058] This surface structure also promotes the ingrowth of bone tissue and, as described above, forms a substantially regular surface structure whose properties can be adjusted by the size of the unit cells or the tetrapod-like basic elements underlying them. Furthermore, the regularity of the structure also promotes a uniform coating of the surface structure. DETAILED EXPLANATION OF PREFERRED EMBODIMENTS

[0059] For the purposes of the present invention, a coating is understood to mean a coating applied by a technical process. Examples of such technical processes include chemical vapor deposition (CVD) or physical vapor deposition (PVD) or plasma spraying processes, such as the titanium plasma spray process already mentioned above.

[0060] As described above, a coating according to the invention comprises titanium, silver, and niobium, as well as preferably up to two additional coating components. For the sake of simplicity, such a coating is referred to below as a titanium-silver coating, with the understanding that it may also comprise additional coating components. It is also noted that, due to the technical coating process, the coating may contain up to a proportion of 3%, 2%, or 1% impurities in the form of other elements or compounds. This applies in particular to a coating consisting of certain coating components.

[0061] The coating is applied to a surface structure of the implant component. A preferred method for creating such a surface structure is a plasma spray process. In the plasma spray process, a plasma jet is generated essentially in a vacuum, to which metal particles are fed, which melt and are accelerated in the high-energy jet. The molten metal particles then impact the surface of the implant component and bond with it. The metal particles preferably comprise or consist essentially of titanium or a titanium alloy.

[0062] A surface structure produced by the plasma spray process preferably has a roughness (Ra) in a range of 20 µm to 80 µm. Furthermore, a surface structure produced by this process particularly has undercuts.

[0063] It was found that these undercuts are not sufficiently coated with a commonly used antimicrobial coating to achieve the desired effect. It is now suspected that this is due in particular to a lower silver content in this area.

[0064] Furthermore, a surface structure produced using a plasma spray process is preferably porous. The porosity is preferably in a range of 10% to 60%, and more preferably in a range of 15% to 60% or in a range of 20% to 50% (measured according to ASTM F1854).

[0065] In these areas, a sufficient pore width can also be provided for the ingrowth of tissue, especially bone tissue. Thus, the surface structure has pore widths in a range of approximately 45 µm to 80 µm, and preferably in a range of 50 µm to 70 µm. The average pore width of all pores is also preferably within this range (arithmetic mean).

[0066] Another, particularly preferred method creates the surface structure using an additive process. Layer melting processes, such as the electron beam layer melting process mentioned above, are particularly suitable for this purpose. The advantage of additive processes is that the surface structure can be defined and uniformly formed on the implant component. Particularly preferably, in such an additive process, the solid material and the surface structure of the implant component are produced essentially in the same manufacturing step.

[0067] As explained above, the surface structure preferably comprises unit cells from which it is constructed. Even more preferably, the unit cells are in turn constructed from at least one, and in particular precisely one, basic element type, such as a tetrapod-like basic element. In this regard, particular reference is made to the porous structures disclosed in patent application WO 2017 / 005514 A1.

[0068] One advantage of a porous structure manufactured using an additive process is that the porosity, pore width, pore size, and / or pore shape can be consistently produced. Furthermore, the formation of the surface structure enables predetermined mechanical properties, such as (directional) elasticity. This allows the surface structure to be tailored specifically to a specific tissue, such as bone or connective tissue.

[0069] A predefined and, in particular, higher porosity of the surface structure can also be achieved through an additive process. The porosity is preferably between 50% and 80%, and even more preferably between 65% and 75% (measured according to ASTM F1854).

[0070] Furthermore, an additive process can easily provide a sufficient pore width for the ingrowth of tissue, particularly bone tissue. Thus, the surface structure has, in particular, pore widths in a range of approximately 100 µm to 1000 µm, preferably in a range of 300 µm to 900 µm, and even more preferably in a range of 500 µm to 800 µm. Due to the regularity of the structure, the average pore width is also essentially predetermined and deviates only slightly from the target dimension due to manufacturing (e.g., the arithmetic mean can deviate by less than 50 µm). In other words, the variance is lower with additive processes than with other processes, such as the plasma spray process mentioned above.

[0071] The pore sizes produced by the above processes preferably have a widest to narrowest pore size ratio that is less than 4:1, 3:1, and more preferably 2:1.

[0072] The coating of the surface structure has one, two, or three layers of the coating in which silver is embedded. The silver is present in the form of silver islands (silver agglomerates), meaning that silver or silver atoms are arranged adjacent to the lattice of the remaining coating components. Due to the size of the silver atoms, it is assumed that only a small proportion, if any, of the silver is interstitially arranged within the lattice.

[0073] In particular, it has been observed that the silver is present in the form of silver agglomerates in the titanium-silver coating. In other words, the silver is present in the coating's lattice but is not integrated into it. The silver agglomerates are preferably in a range of 1 µm to 50 µm, and more preferably in a range of 5 µm to 30 µm.

[0074] Furthermore, it is assumed that the effectiveness of silver is primarily due to the fact that, in the implanted state of the implant component, it transforms into the ionic state upon contact with body fluid through local element formation, thus exerting its antimicrobial effect. This local element formation is enabled very effectively by an arrangement of these islands on the surface of the coating. This arrangement is achieved by at least partially coating the implant component simultaneously with titanium nitride and silver.

[0075] The coating has an antimicrobial effect due to its antimicrobial properties. It is suspected that the silver content of the coating disrupts the formation of a biofilm that these bacteria develop. Due to this disruption, the protection provided by this biofilm no longer functions sufficiently for the bacteria, making them more vulnerable to the patient's immune system or even to active substances.

[0076] Furthermore, it has been observed that the silver can be released from the coating in ionic form. It is assumed that these silver particles, ionized on the surface of the coating, form an inhibition zone in the immediate vicinity of the implant component, where they exert an antimicrobial effect. Consequently, the coating can not only prevent infections spreading directly from the surface of the implant component, but also, in particular, prevent infections in the patient's tissue adjacent to the implant component.

[0077] Preferably, the at% content of silver is lower than the at% content of titanium. In other words, a stoichiometric distribution is not required. The distribution can be super- or sub-stoichiometric.

[0078] The silver content, together with the titanium content and possibly other coating components, not only provides the antimicrobial effect mentioned above, but also changes the mechanical properties compared to a coating without silver. In particular, this structure makes the coating softer and more ductile.

[0079] It is assumed that, due to the associated ductility, the mechanical resistance or strength of the coating is still sufficient to withstand the mechanical influences that occur during implantation of the implant component. Such mechanical influences arise, for example, when creating a press fit of an implant component in the bone tissue, through contact of an implant component with a fastening element, such as when screwing in bone screws to attach a plate, or during assembly with another implant component, such as in a spinal fusion abutment.

[0080] For this reason, this coating is particularly suitable for implant components that, after implantation, support a patient's skeleton or replace parts of that skeleton. With such implant components, mechanical stress on the coating generally occurs during implantation and the assembly of multiple implant components. After implantation, stresses and strains in the coating due to elastic deformations arise, particularly from the everyday stresses the implant component is subjected to in the patient's body. Here, too, this coating is advantageous because it withstands these stresses without losing its protective effect.

[0081] As described above, the coating components can be selected so that the coating is particularly suitable for implant components where abrasion occurs, particularly during implantation of the implant component and / or the assembly of multiple implant components. It has been found that a coating thickness of less than 10 μm, in particular 2.5-6 μm, preferably 3.5-5.5 μm, and even more preferably approximately 4.5 μm, is sufficient for this purpose. This also applies to the TiNb-Ag coating described above, which exhibits particularly high adaptability to deformation of the surface structure.

[0082] Furthermore, the silver content of this coating can partially reduce the difference in its material properties, particularly its elasticity, compared to the underlying material of the surface structure. This can also promote sufficient mechanical resistance and adhesion of the coating.

[0083] In summary, the present coating for the surface structure of an implant component thus shows both advantageous antimicrobial and advantageous mechanical properties, which are beneficial for an implant component coated with this coating, at least in sections.

[0084] Such a coating is preferably produced using the physical vapor deposition (PVD) process mentioned above. Before being introduced into the coating chamber, the implant component to be coated, including its surface structure, can be cleaned with water.

[0085] The implant component is then introduced into the coating chamber, which is subsequently evacuated. For subsequent processes, the implant component is preferably heated to 400 to 600 °C to improve the mobility of ions on the surface structure of the implant component and thus achieve better adhesion and distribution of the coating on the surface structure and any underlying surface of the solid material to be coated.

[0086] It is also possible to clean the implant surface using ion etching. This involves bombarding the implant component with ions (e.g., titanium ions, argon ions) under an inert atmosphere, particularly an argon atmosphere, to remove any oxide layer that may be present on the surface of the uncoated surface structure. This also improves the adhesion of the coating to the surface structure of the implant component.

[0087] After this optional cleaning, the coating is applied to the implant component under an atmosphere. If nitrogen is used as the coating component, the atmosphere used is one that contains at least nitrogen. Otherwise, the coating is applied under an atmosphere that essentially consists of an inert gas.

[0088] As already described above, this coating can be implemented, depending on its desired composition, with at least one silver target, at least one titanium target, and at least one further target with an additional coating component. It is equally possible to use one or more targets that have the at% proportions of silver, titanium, and possibly other coating components intended for the coating. Consequently, the composition of the coating is determined in particular by the composition of the at least one target.

[0089] In order to cause the vaporized target material to scatter on gas particles in the coating chamber so that they can more easily reach the surfaces of undercuts or pores, the coating is carried out under the negative pressure ranges listed above.

[0090] Once the desired atmosphere has been established, the evaporation process of at least one target begins. An arc is particularly preferably used for this purpose, which uses a strong current to release material from the targets by means of an electrical discharge and transfer it into the gas phase. During this discharge, voltages in the range of 15-30 V, preferably in the range of 20-25 V, and currents in the range of 40-70 A are used. However, those skilled in the art will understand that other methods for evaporating the targets can also be used, such as thermal evaporation, electron beam evaporation, or laser beam evaporation.

[0091] At least during part of the coating process, when targets with different materials are used, the coating is carried out simultaneously to create the Ag island structure described above.

[0092] Depending on the material of the surface structure to be coated, a negative voltage of 100 V to 1500 V can also be applied to improve adhesion and layer homogeneity. To achieve the most uniform coating of the surface structure possible, the targets and the implant component can also be moved relative to each other during the coating process.

[0093] After the coating is complete and a cooling phase is completed, the coating chamber is vented again, and the coated implant component can be removed. Cooling is preferably carried out with the assistance of a gas atmosphere (e.g., nitrogen or an inert gas) for improved heat dissipation, thus accelerating the cooling process.

Claims

1. An implant component, comprising: a solid material region; a surface structure connected to the solid material region; a coating which is provided on the surface structure; and wherein the surface structure comprises undercuts which are coated with the coating, characterized in that the coating, as a main component, comprises an atomic proportion in % of Ti and as a further coating component Ag having an atomic proportion in % of 15-25 at% and an atomic proportion in % of Nb, wherein Ag is predominantly arranged in the form of silver agglomerates next to a lattice of the remaining coating components and not or only slightly interstitial in the lattice.

2. The implant component according to claim 1, wherein the undercuts of the surface structure are at least partially formed by an open-pore structure.

3. The implant component according to claim 1 or 2, wherein the open-pore structure was generated by means of a plasma spray coating, in particular a titanium plasma spray coating.

4. The implant component according to any one of the preceding claims, wherein the open-pore structure comprises substantially regularly arranged unit cells and the unit cells are formed preferably as tetrapod-like basic elements.

5. The implant component according to any one of claims 2 to 4, wherein the open-pore structure has a porosity of 10% to 80% and / or a pore width of 45 to 1000 µm.

6. The implant component according to any one of the preceding claims, wherein the surface structure is formed with a thickness of up to 4 mm, 3 mm, 2.5 mm, 2 mm, 1.5 mm, 1 mm or 0.5 mm.

7. The implant component according to any one of the preceding claims, wherein the silver proportion of the coating is at least 18 at%, 20 at% or 22 at% and at most 23 at%, 24 at% or 25 at%.

8. The implant component according to any one of the preceding claims, wherein the coating comprises an atomic proportion in % of N as a further coating component.

9. The implant component according to any one of the preceding claims, wherein the coating is a PVD coating.

10. The implant component according to any one of the preceding claims, wherein the silver agglomerates are present in a range from 1 um to 50 µm, preferably from 5 um to 30 µm.

11. The implant component according to any one of the preceding claims, wherein the coating has a thickness of 1-6 um, 2.5-6 um or 3.5-5.5 µm.

12. The implant component according to any one of the preceding claims, wherein the solid material region comprises or consists of an alloy and the alloy preferably comprises titanium as a main alloy component.

13. A method for applying a coating onto an implant component, wherein the method comprises the steps of: - providing an implant component, in particular an implant component according to any one of the preceding claims, wherein the implant component is formed with a solid material region and with a surface structure connected to the solid material region, and the surface structure comprises undercuts; - introducing the implant component into a coating chamber; - providing at least one target made of a metallic material which comprises at least one of the coating components; - locking the coating chamber; - providing an atmosphere with a pressure of 0.001 to 0.01 mbar; - igniting an electric arc for evaporation of the metallic material of at least one target; and - coating the surface structure with the evaporated metallic material of the at least one target, wherein the coating, as a main component, comprises an atomic proportion in % of Ti and as a further coating component Ag having an atomic proportion in % of 15-25 at% and an atomic proportion in % of Nb, wherein Ag is predominantly arranged in the form of silver agglomerates next to a lattice of the remaining coating components and not or only slightly interstitial in the lattice.

14. The method according to claim 13, wherein the surface structure is formed by fused particles, which is applied by means of a plasma spraying method, in particular by means of a titanium plasma spraying method onto the solid material of the implant component.

15. The method according to claim 13 or 14, wherein the surface structure is constructed of unit cells and is preferably formed by means of a layer melting method, in particular an electron-beam layer melting method.