IMPLANT FOR IMPLANTING INTO AN ORGANISM AND PROCEDURE

Description

[0001] The invention relates to an implant for implantation into an organism, in particular into the human body, and to a method for producing an implant.

[0002] Implants are generally well-known. An implant is an artificial material that is inserted into an organism and remains in the body permanently or temporarily for a defined period of time. Implants often serve to support or replace bodily functions. Implants are made of materials such as titanium or plastic.

[0003] Medical implants can perform a permanent, long-term function in the body or temporarily, for a predefined period of time. The latter type of implant is typically removed from the body. This is necessary, among other things, when the body is in a growth phase, such as in children and young adults, and the implanted implant does not grow with the body. Removing the implant requires further surgery, which can result in the well-known physiological and psychological disadvantages.

[0004] An alternative to implants made of permanent materials are resorbable implants. Resorbable implants are implants that consist of or contain a resorbable material. Resorbable materials are also called bioresorbable materials. Resorbable materials are broken down by the body through degradation and usually do not need to be removed. One advantage of this is that the additional surgery on the body to remove the implant, as described above, is not required.

[0005] Resorbable polymer implants have a number of disadvantages. Some materials lead to inflammation and fistulas, while others are often not stable enough to heal complex or large bone fractures. While steel screws and plates inserted into bone, either temporarily or as permanent implants, meet the stability criteria, they regularly lead to allergic reactions. In addition to steel screws, titanium screws can also be used. These are stable and generally harmless to allergens. However, like steel implants, they usually require surgical removal.

[0006] A further disadvantage of known resorbable implants is that the degradation or breakdown of the implant is not, or only partially, controllable. Resorbable implants generally degrade essentially evenly. This means that the implant also degrades evenly at different functional sites.

[0007] For resorbable implants, which are currently often manufactured by extrusion, it is possible to control the degradation rate by coating the implant or by adding additional alloying elements, such as rare earths. However, this generally only allows for global control of degradation and not for section-specific degradation. Page 3:

[0008] DE 10 2005 032 604 A1 describes a resorbable, body-insertable medical device featuring a non-resorbable coating. US Pat. No. 7,879,367 B2 describes a stent made of a metallic, resorbable material that is intended to dissolve in the body through corrosion. The stent dissolves essentially evenly.

[0009] US 2020 / 0121441 A1 describes resorbable implants with variable degradation that contain a containment layer. The degradation of the implant is influenced by the containment layer. Targeted control of degradation is not taught.

[0010] WO 2019 / 072736 A1 discloses an implant for the tensile-resistant connection of at least two parts of a broken long bone.

[0011] It is therefore an object of the present invention to provide an implant for implantation into an organism and a method that reduce or eliminate one or more of the aforementioned disadvantages. In particular, it is an object of the invention to provide a solution that enables an improved implant. Furthermore, it is an object of the invention to provide a solution that enables improved control of the degradation of an implant.

[0012] This object is achieved with an implant and a method according to the features of the independent patent claims. Further advantageous embodiments of the implant and the method are specified in the respective dependent patent claims. The features listed individually in the patent claims can be combined with one another in any technologically expedient manner and can be supplemented by further features from the description, thereby demonstrating further embodiments of the invention.

[0013] The implant for implantation into an organism, in particular into the human body, comprises a first implant portion having a first degradation rate, and a second implant portion having a second degradation rate, wherein the first degradation rate is lower than the second degradation rate, and wherein the implant consists of or comprises a resorbable material.

[0014] The invention is based on the finding that resorbable implants that degrade essentially uniformly across the entire implant have disadvantages. The function of an implant can be improved by having individual sections of the implant degrade more slowly than others. For example, in a screwed bone plate, the section adjacent to a screw can be designed as the first implant section and the area that supports the bone as the second implant section. As a result, the support section degrades more quickly than the screw section, so that the support section degrades first and is held in its original position by the screw section until complete degradation. This can enable improved healing.

[0015] The first implant section and the second implant section can be adjacent to each other in any implant orientation. The first implant section and the second implant section are preferably arranged such that both implant sections form part of the implant surface. In this embodiment, the first implant section and the second implant section are arranged, in particular, next to each other.

[0016] Alternatively or additionally, the first implant section and the second implant section can also be arranged such that one of the implant sections forms the implant surface and / or the other implant section is surrounded, preferably completely surrounded, by the implant section forming the implant surface. Thus, a gradient in the degradation rate can be realized in a particularly advantageous manner.

[0017] The implant may also comprise multiple first implant sections and / or multiple second implant sections. Furthermore, the implant may also comprise three or more implant sections, each with different degradation rates.

[0018] The degradation rate is the rate at which the implant or an implant section is degraded within or by the organism. The degradation rate can also be preferably expressed as Page 5:

[0019] Degradation rate is usually not linear, as it is initially high and decreases over time.

[0020] A common unit for defining the degradation rate is millimeters per unit of time, for example, millimeters per day, per week, per month, and / or per year. Furthermore, it is preferred that the degradation rate be expressed as a surface-related mass loss per unit of time, for example, using the unit mg / cm² / day. The degradation rate as a surface-related mass loss per unit of time is determined, for example, using the formula mass loss divided by the surface area divided by a unit of time.

[0021] The first implant section and the second implant section are preferably made essentially of the same resorbable material. The implant can consist of the first implant section and the second implant section or can comprise the first implant section and the second implant section. The implant is preferably designed without a coating. The implant can comprise the resorbable material or can consist of it. It is particularly preferred that the implant comprises more than 50%, more than 75%, more than 90%, or more than 95% of the resorbable material.

[0022] The implant is characterized in that the first implant section has a first cavity structure with a first filling density, and the second implant section has a second cavity structure with a second filling density, wherein the first filling density is higher than the second filling density.

[0023] The filling density describes, in particular, the ratio of the resorbable material to the free space, which is usually filled with air. The filling density can be specified as a percentage between 0% and 100%. A filling density of 100%, for example, means that the corresponding implant section is solid. Page 5a

[0024] A void structure with a filling density of 100% is preferably understood to mean an essentially solid structure without voids.

[0025] It may be preferred that the first cavity structure has a first filling density of 100%. The lower the filling density, the higher the degradation rate is generally. For this reason, this development preferably provides for the first filling density to be higher than the second filling density, so that the first degradation rate is lower than the second degradation rate.

[0026] A further preferred development of the implant is characterized in that the implant has a transition section arranged between the first implant section and the second implant section. The transition section preferably has a cavity structure, which further preferably has a cavity structure adjacent to the first implant section that essentially corresponds to the first cavity structure and / or a cavity structure adjacent to the second implant section that essentially corresponds to the second cavity structure. The change from the first cavity structure to the second cavity structure of the transition section occurs, in particular, gradually.

[0027] An implant with two or more differently shaped cavity structures is superior to a single-foam implant because the degradation rate can be advantageously controlled. In particular, the geometric definition of the cavity structures, as explained below, enables targeted control of the degradation rate without having to resort to uncertain statistical methods for distributing the cavity size, which are often inadequate in the medical field.

[0028] In a further preferred embodiment of the implant, the first filling density is selected depending on the first degradation rate and / or the second filling density is selected depending on the second degradation rate. For example, a preferred first degradation rate and / or second degradation rate can be specified from a medical perspective. Based on this specified degradation rate, the implant can be designed with regard to its first and / or second filling density in such a way that the medical requirements are met.

[0029] A further preferred development of the implant is characterized in that a filling density ratio of the first filling density and the second filling density is selected such that the first degradation rate and the second degradation rate form a predefined speed ratio.

[0030] In a further preferred embodiment of the implant, it is provided that the first cavity structure and / or the second cavity structure is / are geometrically defined. "Geometrically defined" can mean, for example, that they have a geometric pattern. Furthermore, "geometrically defined" can mean that the first cavity structure and / or the second cavity structure have geometric figures. Furthermore, "geometrically defined" preferably means that they are formed based on the laws of geometry.

[0031] A further preferred development of the implant is characterized in that cavities of the first cavity structure and / or the second cavity structure have a cross-section. The cross-section can be of any desired shape. Furthermore, the cross-section can be triangular, quadrangular, pentagonal, hexagonal, polygonal, and / or gyroidal. The cavity structures can have cross-sections with one, two, several, or all of these shapes.

[0032] These possible cross-sections, which can occur individually or in combination in the first cavity structure and / or the second cavity structure, result in correspondingly shaped three-dimensional cavities. For example, a cavity with a quadrangular cross-section can assume a cubic shape in two spatial directions. The number of cavities can be arbitrarily high and can be adapted to individual requirements, in particular to a predefined degradation rate. The cavities are preferably delimited and / or separated from one another by cavity walls. The thickness of the cavity walls is arbitrary and can vary within the implant.

[0033] A further preferred embodiment of the implant is characterized in that the first cavity structure and / or the second cavity structure has a plurality of cavities, wherein the cavities of the first cavity structure have a smaller cavity size than the cavities of the second cavity structure. A cavity size can be understood, for example, as a cavity volume, in particular an average cavity volume. Furthermore, a cavity size can be understood as a cavity dimension, in particular an average cavity dimension, particularly in the direction of the greatest extent of the respective cavity.

[0034] The fact that the cavities of the first cavity structure have a smaller cavity size than the cavities of the second cavity structure can also mean that the cavities of the first cavity structure have a cavity size of zero and thus there are essentially no cavities in the first cavity structure, so that it is solid.

[0035] The fact that the cavities of the first cavity structure have a smaller cavity size than the cavities of the second cavity structure can mean in particular that more than 75%, more than 90% or more than 95% of the cavities of the first structure are smaller than the cavities of the second cavity structure.

[0036] A further preferred development of the implant is characterized in that the cavities of the first cavity structure and / or the cavities of the second cavity structure are designed to be closed to one another. "Closed to one another" means, in particular, that they are separated from one another. "Closed" can also mean that there is essentially no fluidic connection between two adjacent cavities. Alternatively or additionally, two adjacent cavities can also have a connection, for example, a fluidic connection, to one another.

[0037] In a further preferred embodiment of the implant, the first implant section and / or the second implant section are of volumetric design. A volumetric design is understood to mean, in particular, a three-dimensional geometry that, in addition to a flat design, also has a non-negligible thickness. A coating does not typically fall under this definition.

[0038] Another preferred embodiment of the implant is characterized in that the resorbable material is a metal or comprises a metal. It is particularly preferred that the resorbable material is a magnesium alloy or comprises a magnesium alloy. Furthermore, the resorbable material can be or comprise a polylactide.

[0039] An implant made of or comprising a magnesium alloy offers several advantages. The implant is metallic and therefore offers high stability, generally greater than that of plastics. Furthermore, such implants are completely remodeled in the body and, during this remodeling, form the basis for new mineralized bone substance. Furthermore, such implants are sufficiently elastic to prevent stress shielding, thus stimulating bone formation and promoting healing.

[0040] In a further preferred embodiment of the implant, the implant is manufactured using an additive manufacturing process. The additive manufacturing process is preferably or includes a material extrusion process. It is further preferred that the material extrusion process be combined with a sintering process, with the sintering process preferably being used after the material extrusion process.

[0041] In a further preferred embodiment of the implant, the first implant section is adjacent to the second implant section in at least one implant plane. Furthermore, it is preferred that the first implant section is enclosed by the second implant section in at least one implant plane.

[0042] A further preferred development of the implant is characterized in that the first implant section is a fastening section and / or the second implant section is a structural section. Alternatively or additionally, the first implant section can comprise the fastening section and / or the second implant section can comprise the structural section. The fastening section preferably has one, two, or more through-openings. The fastening section is preferably designed as a screw-connection section. The structural section is further preferably designed as a reinforcement section.

[0043] In a further preferred embodiment of the implant, the implant is a bone plate. Alternatively, the implant can also be a bone screw, a wound clip, a stent, a device for implant fixation, and / or a carrier material for tissue engineering. It is particularly preferred that the bone plate or one of the aforementioned implant configurations comprises the fastening section and the structural section. Thus, the bone plate can be screwed to a bone by means of the fastening section. The structural section serves to support the bone.

[0044] In a further preferred embodiment of the implant, at least one cavity contains a drug. This embodiment has the advantage that the drug is released upon degradation of the implant, so that the rate of drug release can be controlled by varying degradation rates.

[0045] Furthermore, it is preferred that the implant has a coating. The coating preferably consists of or comprises a resorbable material. The coating can essentially completely or partially form an implant surface.

[0046] According to a further aspect, the object mentioned at the outset is achieved by a method for producing an implant, in particular an implant according to one of the embodiments described above, comprising the steps of: producing a first implant section from or with a resorbable material which has a first degradation rate, and producing a second implant section from or with a resorbable material which has a second degradation rate, wherein the first degradation rate is lower than the second degradation rate.

[0047] A preferred embodiment of the method provides that the first implant section and / or the second implant section is produced with a cavity structure, wherein the first implant section has a first filling density and / or the second implant section has a second filling density, wherein preferably the first filling density is higher than the second filling density.

[0048] Furthermore, it is preferred that the first implant section and / or the second implant section is produced using an additive manufacturing process.

[0049] The method and its possible further developments have features or process steps that make them particularly suitable for use with the implant and its further developments. For further advantages, design variants, and details of the method and its possible further developments, please refer to the above description of the corresponding features and further developments of the implant.

[0050] Preferred embodiments are explained using the accompanying figures. They show: Figure 1: a schematic, two-dimensional view of an exemplary embodiment of an implant; Figure 2: another schematic, two-dimensional view of an exemplary embodiment of an implant; and Figure 3: a schematic method.

[0051] In the figures, identical or essentially functionally identical or similar elements are designated by the same reference numerals.

[0052] Figure 1 shows an implant 1 for implantation into an organism, in particular into the human body. The implant 1 comprises a first implant section 2, which is designed as a screw section 4. Furthermore, the implant 1 comprises a second implant section 6, which is designed as a reinforcement section 8.

[0053] The first implant section 2 has a first degradation rate, and the second implant section 6 has a second degradation rate. The implant 1 consists of a resorbable material, which is a magnesium alloy. The implant 1 can also comprise or consist of another suitable resorbable material.

[0054] The first implant section 2 has a first cavity structure 10. The first cavity structure 10 also has a first filling density, wherein it can be seen that the first cavity structure 10 is comparatively densely meshed. The second implant section has a second cavity structure 14, which has a second filling density. It is shown that the second cavity structure 14 is less densely meshed than the first cavity structure 10.

[0055] The cavity structures 10, 14 each have cavities 12, 16. The first implant section 2 further has a first screw opening 18 and a second screw opening 20. Furthermore, a medicament 22 is enclosed in one of the cavities 12 of the second implant section 6.

[0056] The first cavity structure 10 and the second cavity structure 14 are geometrically defined. The cavities of the first cavity structure 10 and the second cavity structure 14 have a triangular cross-section. The cavities can, for example, be pyramid-shaped.

[0057] The first cavity structure 10 and the second cavity structure 14 have a plurality of cavities 12, 16, wherein the cavities of the first cavity structure 10 have a smaller cavity size than the cavities of the second cavity structure 14. The first degradation rate is therefore lower than the second degradation rate.

[0058] The cross-section of the cavities 12 of the second cavity structure has an area approximately four times as large as the cross-section of the cavities 12 of the first cavity structure 10. The cavities 12, 16 of the cavity structures 10, 14 are formed closed to one another.

[0059] The first implant section 2 borders the second implant section 6 and is enclosed by it in the view plane. The implant 1 is manufactured using an additive manufacturing process.

[0060] Figure 2 shows a further embodiment of an implant 1'. The implant 1' is essentially constructed in the same way as the implant 1, whereby the first implant section 2 and the second implant section 6 differ from those in Figure 1 differ in that their cross-sections are hexagonal or honeycomb-shaped.

[0061] Figure 3shows a schematic method. The method comprises steps 100, 102, 104. In step 100, a resorbable material is provided. In step 102, a first implant section 2 is produced from the resorbable material. The first implant section 2 has a first degradation rate, which is essentially caused by the created cavity structure 10. In step 104, a second implant section 6 is produced from the resorbable material, which has a second degradation rate, which is essentially caused by the created cavity structure 14.

[0062] The first degradation rate is lower than the second degradation rate. This is achieved in particular by the filling density of the second cavity structure 14 being lower than the filling density of the first cavity structure 10. Steps 102 and 104 can also be performed simultaneously. Furthermore, step 104 can also be performed before step 102.

[0063] It is preferred that the first implant section 2 and the second implant section 6 be produced with the aforementioned cavity structure 10, 14, wherein the first implant section 2 has a first filling density and the second implant section 6 has a second filling density. The first filling density is lower than the second filling density.

[0064] Implant 1, with two implant sections 2 and 6 with different degradation rates, enables complex implants and new treatment options, for example, for bone fractures. Depending on which section of the implant has to bear longer loads, a higher or lower degradation rate can be specified. In particular, this makes it possible to control degradation on a section-specific basis, thus allowing greater flexibility in medical treatment. REFERENCE SYMBOL

[0065] 1, 1'Implant 2First implant section 4Screw section 6Second implant section 8Reinforcement section 10First cavity structure 12Cavity 14Second cavity structure 16Cavity 18First screw opening 20Second screw opening 22Medicine

Claims

1. Implant (1, 1') for implantation in an organism, in particular in the human body, comprising - a first implant section (2) which has a first degradation speed, and - a second implant section (6) which has a second degradation speed, - wherein the first degradation rate is less than the second degradation rate, and - wherein the implant (1, 1') consists of or comprises a resorbable material, - characterized in that the first implant portion (2) has a first cavity structure (10) with a first filling density and the second implant portion (6) has a second cavity structure (14) with a second filling density, wherein the first filling density is higher than the second filling density.

2. Implant (1, 1') according to the preceding claim 1, wherein - the first filling density is selected as a function of the first degradation rate and / or the second filling density is selected as a function of the second degradation rate, and / or - a filling density ratio is selected from the first filling density and the second filling density in such a way that the first degradation speed and the second degradation speed form a predefined speed ratio.

3. Implant (1, 1') according to any one of the preceding claims, wherein - the first cavity structure (10) and / or the second cavity structure (14) is or are configured in a geometrically defined manner, and / or - cavities of the first cavity structure (10) and / or the second cavity structure (14) have a cross-section that is configured triangular, quadrangular, pentagonal, hexagonal, polygonal and / or gyroidal.

4. Implant (1, 1') according to any one of the preceding claims, wherein - the first cavity structure (10) and / or the second cavity structure (14) has a plurality of cavities (12, 16), wherein the cavities (12) of the first cavity structure (10) have a smaller cavity size than the cavities (16) of the second cavity structure (14).

5. Implant (1, 1') according to any one of the preceding claims, wherein - the cavities (12) of the first cavity structure (10) and / or the cavities (16) of the second cavity structure (14) are configured to be closed with respect to each other.

6. Implant (1, 1') according to any one of the preceding claims, wherein - the first implant section (2) and / or the second implant section (6) is or are configured in the form of a volume.

7. Implant (1, 1') according to any one of the preceding claims, wherein the resorbable material is a metal, in particular a magnesium alloy, or comprises a metal, in particular a magnesium alloy.

8. Implant (1, 1') according to any one of the preceding claims, wherein the implant (1, 1') is produced using an additive manufacturing process.

9. Implant (1, 1') according to any one of the preceding claims, wherein the first implant portion (2) is adjacent to and preferably enclosed by the second implant portion (6) in at least one implant plane.

10. Implant (1, 1') according to any one of the preceding claims, wherein the first implant section (2) is and / or comprises a fastening section, in particular a screwing section (4), and / or the second implant section (6) is and / or comprises a structural section, in particular a reinforcing section (8) for reinforcing a bone.

11. Implant (1, 1') according to any one of the preceding claims, wherein the implant (1, 1') is a bone plate.

12. Implant (1, 1') according to any one of the preceding claims, wherein at least one cavity (12, 16) contains a drug.

13. Method for producing an implant (1, 1'), in particular an implant (1, 1') according to any one of the preceding claims 1-12, comprising the steps of: - Producing a first implant portion (2) from or with a resorbable material having a first degradation rate, and - creating a second implant portion (6) from or with a resorbable material having a second degradation rate, - wherein the first degradation rate is lower than the second degradation rate, - characterized in that the first implant portion (2) and the second implant portion (6) are produced with a cavity structure (10, 14), wherein the first implant portion (2) has a first filling density and the second implant portion (6) has a second filling density, wherein the first filling density is higher than the second filling density.

14. Method according to the preceding claim 13, wherein - the first implant section (2) and / or the second implant section (6) is produced using an additive manufacturing process.