Implantable prosthesis holder, use thereof and arrangement comprising a prosthesis holder and a prosthesis

Abstract

Patient-specific, pre-molded, implantable epithesis holder (1), made of a biocompatible, artifact-free or low-artifact material, such as a plastic or a ceramic, wherein the epithesis holder (1) has at least one attachment point (6, 6.1, 6.2) for attaching it to a patient's own support structure, such as a bone structure, and first connection means (4, 4.1) to which an external epithesis (8) equipped with second connection means complementary to the first connection means (4, 4.1) is held when placed in intervention with the first connection means (4, 4.1).

Description

[0001] The invention relates to an implantable epithesis holder. The invention further relates to the use of such an epithesis holder and also to an arrangement comprising such an epithesis holder and an epithesis belonging to the epithesis holder.

[0002] Implantable prosthesis retainers are needed to hold and support external prostheses. These retainers are typically bone-anchored implants equipped with connectors for attaching the prosthesis. Magnetic systems or bar-and-rider constructions are frequently used for this purpose.

[0003] Titanium meshes are typically used as implantable prosthesis holders, serving as carriers for the connecting element(s), such as retention magnets. These titanium meshes are made of a titanium alloy and feature structures designed for anchoring fasteners to the bone. They are either inserted into the bone or screwed to the bone externally. These prosthesis holders are standard, manufactured prosthesis holders. While generally sufficient for holding a prosthesis, the selection is limited and sometimes not suitable for optimal patient care. Although these prosthesis holders are biocompatible, they are not very mechanically robust. The titanium or...Titanium alloy prosthesis holders can bend very easily in the event of falls or impacts and, in such cases, must be surgically replaced with new implants. A further disadvantage is that they are visible in imaging procedures, such as CT or MRI scans, and / or cause artifacts. Both of these are undesirable for image evaluation. For this reason, if such scans are required during a patient's treatment or care, for example, during tumor treatment, an implant-fixed prosthesis can only be used after the completion of this treatment. Since such scans often need to be performed over an extended period, for example, as a consequence of tumor treatment, this time is inconvenient for the patient, as an implant-fixed prosthesis cannot be worn during this entire period.

[0004] While prostheses can be fixed to the patient using skin adhesive, this method is only considered as a temporary solution. Cleaning is difficult and often impossible for patients without assistance. Furthermore, the use of skin adhesives leads to faster wear and tear of the prosthesis. In some cases, it also increases the risk of fungal and bacterial colonization.

[0005] Based on this state of the art, the invention aims to propose an implantable epithesis holder that does not interfere with required imaging procedures compared to conventional epithesis holders and that also has a wider range of applications compared to conventional epithesis holders.

[0006] This problem is solved according to the invention by a patient-specific, pre-molded, implantable epithesis holder made of a biocompatible, artifact-free or low-artifact material, such as a plastic or a ceramic, wherein the epithesis holder has at least one attachment point for attaching it to a patient's own support structure, such as a bone structure, and first connection means on which an external epithesis equipped with second connection means complementary to the first connection means is held when engaged with the first connection means.

[0007] This prosthesis holder is patient-specifically preformed. This means that the prosthesis holder's shape is adapted to the existing supporting structure of the patient where it is to be implanted. Therefore, this prosthesis holder is individually manufactured for implantation at a very specific location for a particular patient. It is produced through a primary forming process and is thus not a part cut from a larger piece. Consequently, all three dimensions are available for the design of the prosthesis holder during its primary forming. The term "primary forming" as used in this context refers, for example, to casting processes or additive manufacturing processes. The latter is often also referred to as 3D printing.

[0008] This method of manufacturing the epithesis holder, which is 3D-modeled prior to the primary forming process, allows for its design to function not only as a retainer for an external epithesis but also as a bone implant. This enables the holder to replace missing bone. Consequently, this epithesis holder can secure an implant-fixed epithesis even in areas where a conventional epithesis holder could not be attached due to a lack of bone structure. This also makes implant fixation of the external epithesis possible in areas where traditional epithesis fixation was only possible using skin adhesives.

[0009] The material from which the prosthesis holder is made is also unique. It is biocompatible and, most importantly, artifact-free or at least minimally artifact-producing. Therefore, such a prosthesis holder can be implanted very early in the course of necessary treatment or care without adversely affecting the results of imaging procedures. Suitable materials include, for example, a biocompatible plastic or a suitable ceramic.

[0010] Such an epithesis holder has at least one attachment point for securing it to an existing bone or bone structure. Typically, such an epithesis holder has several attachment points. Due to the patient-specific design of the epithesis holder, these are positioned at locations suitable for the individual patient. This means that when attaching the epithesis holder to the patient's supporting structure, typically their bone structure, one is not limited to the predetermined attachment points of a standard epithesis product, but can instead place them at locations that are particularly well-suited for epithesis holder attachment. In addition to the attachment points, such an epithesis holder has connectors for attaching an external epithesis. These connectors are preferably magnetic fasteners with a sufficient holding force.The epithesis itself is equipped with complementary secondary attachments. If these attachments of the epithesis holder are retaining magnets, the epithesis is typically equipped with secondary magnets, with the polarity of the magnets in the epithesis holder and that of the complementary magnets in the epithesis being the same, so that they attract each other. If an external epithesis is to be held magnetically on such an epithesis holder, it can also be provided that either the first or the second attachments are retaining magnets and the respective complementary attachments are not retaining magnets, but simply ferromagnetic material. Sufficient fixation of an external epithesis can also be achieved in this way.It is understood that the epithesis holder may also have mechanical connecting means either instead of or in addition to the magnetic connecting means described above.

[0011] A particularly preferred material for manufacturing such an epithesis holder is a polymer material from which the epithesis holder can be produced using additive manufacturing (3D printing). In this regard, a plastic material from the polyaryletherketone group is especially preferred. Due to its advantages in imaging procedures (virtually species-free), polyetheretherketone (PEEK) is the preferred material from this group. This plastic is not only biocompatible, like the others, but also possesses bone-like material properties with regard to its density and elasticity. Especially when the epithesis holder simultaneously serves as a bone replacement structure, force transmission across the epithesis holder is similar to that of bone.Therefore, such force transmission is physiologically particularly advantageous compared to implants made of titanium or ceramic, materials which have entirely different properties than bone. A particular advantage of using PEEK as a material for manufacturing an epithesis holder is its suitability for 3D printing. PEEK filaments are typically used for this purpose.

[0012] A key advantage of using a polymer material, particularly PEEK, is that its material properties can be modified through doping. For example, ceramic or fiber doping can be incorporated into the material. This allows for the design of patient-specific prosthesis holders, including the choice of additives, to tailor them to the specific patient's needs. Doping with barium sulfate, for instance, results in a radiopaque prosthesis holder made of PEEK. Such doping is useful when the implant needs to be visualized during imaging procedures. A key benefit is that this is achieved without compromising the mechanical advantages of the PEEK material and without the artifacts associated with metal prosthesis holders.Thus, the density or elasticity of the epithesis holder can be influenced or adjusted accordingly by selecting and using the quantity of the additive(s) intended for doping.

[0013] To create an epithesis, the epithesis holder preferably has several spaced-apart connection points, each equipped with a first connection element. These can be connection elements that act in the same way or those that act differently. For example, magnetically acting connection elements can be combined with mechanically acting ones.

[0014] Especially when the prosthesis holder also serves as a bone replacement structure and thus a bone implant, it is advantageous to provide a central connection area with at least one, but preferably several, connection points to which one or typically several structural arms are molded. These structural arms project from the central connection area and are typically equipped with at least one attachment point in their larger end section, via which the prosthesis holder can be attached to existing bone. It is also possible to mold connection point extensions onto such a central area, which bear one or more further connection points that are then located outside the central connection area.

[0015] If one or more holding magnets are provided as the initial connection means, the necessary holding structures for securing such a holding magnet can be formed during the initial shaping process of the epithesis holder, at least in their basic form. This does not, of course, preclude subsequent processing.

[0016] Another advantage of using a plastic material, such as PEEK, is that the retaining magnet can be encapsulated within the prosthesis holder without impairing its function. Therefore, such a retaining magnet could even be positioned and incorporated during the initial shaping of the prosthesis holder.

[0017] To manufacture such an epithesis holder, established process steps are initially used. The first step involves creating image data of the patient's existing bone structure in the area where the epithesis is to be held. This primarily concerns medical imaging data of the bone structure in this area and the surrounding region. A virtual model of the affected body area is then created from this image data. This allows for further modeling adjustments to be made to the model, if necessary. In a subsequent step, the epithesis holder is modeled in a computer-generated 3D model.This creates a three-dimensional digital epithesis holder model that takes into account the patient-specific anatomical structures as well as the functional aspects of the epithesis holder such as fit, stability, attachment options, intended use possibly also as a bone replacement and, of course, aesthetic requirements.

[0018] Based on this 3D model, the prosthesis holder is preferably manufactured using additive manufacturing. Further processing steps can follow this initial forming process, such as post-processing of specific contours and / or surface finishing or treatment. Such post-treatment can be mechanical and, in some cases, chemical. If the initial attachment elements belonging to the prosthesis holder are not directly formed during the initial forming process, or if receiving structures for the attachment elements have been formed by the initial forming process, the attachment elements are subsequently mounted.

[0019] The invention is explained below using an exemplary embodiment with reference to the accompanying figures. These show: Fig. 1: A 3D model of part of a patient's skull, created from medical image data, Fig. 2: A top view of an epithesis holder for holding a nasal epithesis, modeled and manufactured based on the 3D model of the skull of the Fig. 1, Fig. 3: the patient's skull with the epithesis holder of the Fig. 2 with an external nasal prosthesis to be held by the prosthesis holder and Fig. 4: The representation of the skull with the epithesis holder according to the Fig. 2 with the nasal prosthesis attached to the prosthesis holder.

[0020] In a first step of the process for manufacturing an epithesis holder for a nasal prosthesis, a virtual 3D model was created from medical image data of the upper part of a patient's skull. This model is in Fig. Figure 1 is shown schematically. It is clearly visible that parts of the right upper jaw are missing. Due to a tumor, these bone fragments, as well as the patient's nose, had to be removed. Based on this 3D model, a prosthesis holder was computer-aidedly designed. This holder not only serves to support a nasal prosthesis but also replaces a portion of the missing upper jawbone. The virtual design of the prosthesis holder is tailored to the patient's specific characteristics, particularly the bone structure and its quality. Due to the missing portion of the right upper jaw, this area of ​​bone is not considered sufficiently stable for attaching a prosthesis holder. Therefore, the attachment points for securing the prosthesis holder to the remaining intact bone structure were chosen to ensure attachment in these mechanically stable bone areas.At the same time, the patient-specific anatomy of the nose, and thus of the nasal prosthesis, is taken into account in the modeling of the prosthesis holder.

[0021] Fig. Figure 2 shows the epithesis holder 1, additively manufactured based on the previously generated 3D model. The epithesis holder 1 is made of ceramic-doped PEEK, with the ceramic doping in the illustrated embodiment being approximately 15%. The epithesis holder 1 has a central connection area 3 located in front of the nasal cavity opening in the skull bone structure. This central connection area 3 is indicated by dashed lines in the figure. This central connection area 3 carries two retaining magnets 4 as the primary connection means for holding the nasal epithesis. Three structural arms 5, 5.1, 5.2 are molded onto the central connection area 3. Each structural arm 5, 5.1, 5.2 has an attachment point 6, 6.1, 6.2 in its enlarged end section. These are designed as openings. Screws are used to attach the epithesis holder 1 to the skull bone structure. These are shown schematically in Figure 2. Fig. 2 are inserted into the attachment points 6, 6.1, 6.2, which are designed as openings. In particular, the structural arms 5, 5.1 are wider in the section projecting to the respective attachment point 6, 6.1 than in the part of the structural arm 5, 5.1 that connects to the central connection area 3. This ensures that the epithesis holder 1 has a larger contact area, and thus a larger pressure surface, against the bones of the skull in these areas.

[0022] A connection point extension 7 with a further connection point 4.1 is molded onto the central area of ​​the epithesis holder 1. Connection point 4.1 is also equipped with a retention magnet 4.1 as the primary connection element. The connection point extension 7 simultaneously serves to provide a lining for the nasal epithesis in the area where no maxillary bone is present.

[0023] Fig. Figure 3 shows the patient's injuries 2 with the attached prosthesis holder 1. Next to the skull 2, the nasal prosthesis 8, which is to be held by the prosthesis holder 1, is shown. This prosthesis is modeled on the patient's original nose and has complementary prosthesis magnets on its back, corresponding to the prosthesis holder 1's first attachment points 4, 4.1, and complementary prosthesis magnets as second attachment points at those positions so that, when the nasal prosthesis 8 is attached to the prosthesis holder 1, the attachment points of the prosthesis holder 1 and the nasal prosthesis 8 interact. Fig. Figure 4 shows the nasal prosthesis 8 attached to the prosthesis holder 1. The retaining magnets 4, 4.1 of the prosthesis holder 1 are engaged and thus in operative connection with the complementary retaining magnets of the nasal prosthesis 8. This ensures that the prosthesis is securely attached to the prosthesis holder 1 and can be easily removed by the patient if necessary.

[0024] The epithesis holder 1 can be used as an implant in its entirety, so that it is covered by skin, or it can be only partially covered by skin, so that the connecting means are freely accessible or completely exposed.

[0025] The invention has been described with reference to exemplary embodiments. Without departing from the scope of protection described by the applicable claims, numerous further embodiments of the inventive concept would be apparent to a person skilled in the art, without these needing to be explained in more detail within the scope of these explanations. Reference symbol list 1 epithesis holder 2 skulls 3 Central connection area 4, 4.1 Holding magnet 5, 5.1, 5.2 Low structure 6, 6.1, 6.2 Mounting point 7 Connection point extension 8 Nasal prosthesis

Claims

[1] Patient-specific, pre-molded, implantable epithesis holder (1) made of a biocompatible, artifact-free or low-artifact material, such as a plastic or a ceramic, wherein the epithesis holder (1) has at least one attachment point (6, 6.1, 6.2) for attaching it to a patient's own support structure, such as a bone structure, and first connection means (4, 4.1) to which an external epithesis (8) equipped with second connection means complementary to the first connection means (4, 4.1) is held when placed in intervention with the first connection means (4, 4.1). [2] Epithesis holder according to claim 1, characterized by , that the epithesis holder (1) is made of a polymer material, in particular of a material of the group of polyaryletherketones, in particular of polyetheretherketone (PEEK). [3] Epithesis holder according to claim 2, characterized bythat the plastic material has a ceramic doping and / or a fiber doping. [4] Epithesis holder according to claim 2 or 3, characterized by , that the epithesis holder (1) is also a bone replacement implant, by which a bone structure missing on the patient side is replaced, wherein the first connecting means (4, 4.1) for holding an external epithesis (8) are spaced apart from the at least one attachment point (6, 6.1, 6.2). [5] Epithesis holder according to any one of claims 1 to 4, characterized by , that the first connecting means (4, 4.1) are arranged at several connection points spaced apart from each other. [6] Epithesis holder according to claim 5, characterized by , that the epithesis holder (1) has a central connection area (3) with at least one connection point, wherein several structural arms (5, 5.1, 5.2) each supporting at least one attachment point (6, 6.1, 6.2) are molded onto the central connection area (3). [7] Epithesis holder according to claim 6, characterized by , that at least one connection point extension (7) bearing a connection point is formed on the middle area of ​​the epithesis holder (1). [8] Epithesis holder according to any one of claims 1 to 7, characterized by , that the first connecting means are designed as a holding magnet anchored in the epithesis holder or as holding magnets anchored in the epithesis holder (4, 4.1). [9] Epithesis holder according to claim 8 in its indirect or direct reference to claim 2 or 3, characterized by , that the holding magnet(s) (4, 4.1) are encapsulated in the epithesis holder (1). [10] Use of an epithesis holder according to any one of claims 1 to 9 as an implant attached to a patient-side support structure, such as a bone structure, for holding an implant-fixed epithesis (8). [11] Use of an epithesis holder according to claim 10, characterized by, that the epithesis holder (1), when implanted, serves as a bone replacement structure and is connected to a patient-side bone structure with at least one attachment point (6, 6.1, 6.2). [12] Arrangement comprising an epithesis holder (1) according to any one of claims 1 to 9 and an epithesis (8) connectable to the epithesis holder (1) for holding the same on it, wherein the epithesis (8) has second connecting means complementary to the first connecting means (4, 4.1) of the epithesis holder (1), such that when the first and second connecting means are engaged with each other, the epithesis (8) is fixed and held on the epithesis holder (1).

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