Temporal bone implant and method for constructing and / or manufacturing a temporal bone implant

Abstract

The present invention relates to a temporal bone implant (SI) provided for at least partially reconstructing the posterior wall of the external auditory canal, comprising a first portion (A1) which is shaped as a tube or tube segment and designed to form at least one wall portion of the posterior wall by covering a space within the temporal bone, thereby separating the auditory canal from the space. [Solution] The first part (A1) transitions into a plate-shaped second part (A2) oriented laterally to the first part (A1). This second part (A2) is attached to the mastoid process of the temporal bone and, together with the first part (A1), is provided to cover the gap.

Description

Technical Field

[0001] The present invention relates to a temporal bone implant comprising a first part shaped as a tube or tube segment provided for at least partially repairing the posterior wall of the external auditory canal, forming at least one wall portion of the posterior wall by covering a void in the temporal bone, and thereby designed to separate the ear canal from the void. The present invention further relates to a method for constructing and / or manufacturing a temporal bone implant.

Background Art

[0002] In chronic diseases of the middle ear region, in certain cases, surgical treatment in the form of radical mastoidectomy may be required. In radical mastoidectomy on the temporal bone, the mastoid process (mastoid part) is incised to form an open cavity consisting of the epitympanum, mastoid process, and ear canal of the middle ear, and usually, the posterior ear canal wall is partially removed. This cavity is often also called the mastoid cavity or radical cavity. In the case of a prominent cholesteatoma which is chronic suppurative otitis media of the middle ear, radical mastoidectomy may be necessary. The purpose of radical mastoidectomy is to completely remove the cholesteatoma matrix. In addition to reconstruction of the posterior ear canal wall with cartilage (skin) pieces (sometimes also called the method of preserving the posterior wall of the external auditory canal), implants that can be used to repair the posterior wall of the ear canal are also known.

[0003] German Patent Application Publication No. 3117025 discloses an implant provided for partial or total reconstruction of the posterior ear canal wall, which is partially or totally removed due to a pathological condition and replaced with an implant. The implant has a body shaped as a tube or tube segment and designed to reproduce the anatomical state of the posterior ear canal wall by the shape of the tube or tube segment.

Summary of the Invention

[0004] Building upon the prior art described above, the problem addressed by the present invention is to provide a temporal bone implant that enables the repair of the posterior wall of the ear canal with minimal aftercare required.

[0005] This problem is solved in terms of a device, based on the combination of the preamble of additional independent claim 1 and its characteristic features. In terms of a method, this problem is solved in terms of the combination of the preamble of additional independent claim 11 and its characteristic features. Each subsequent dependent claim describes a preferred evolution of the invention. Further preferred embodiments can be understood from the specification and drawings.

[0006] According to additional independent claim 1, a temporal bone implant provided for at least partial repair of the posterior wall of the external auditory canal has a first portion, which is shaped as a tube or tube segment and is designed to form at least one wall portion of the posterior wall by covering a space within the temporal bone, thereby separating the auditory canal from the space.

[0007] Therefore, the implant according to the present invention is designed for use in the temporal bone (temporal bone) and is used in this application to at least partially repair the posterior wall of the external auditory canal. Preferably, the temporal bone implant is used in cases of surgically formed mastoid cavity, often also called a radical cavity, formed by radical mastoidectomy.

[0008] According to the present invention, the temporal bone implant comprises a first portion designed to cover a cavity within the temporal bone, thereby separating the external auditory canal to be repaired from the cavity. This separation allows the first portion to form a part of the posterior bony wall of the external auditory canal (external auditory canal bone). Therefore, when the temporal bone implant is used, the first portion delineates the external auditory canal from the cavity formed within the temporal bone. In particular, when the temporal bone implant is used, its first portion covers a cavity within the tympanic region (pars tympanica) of the temporal bone, and the first portion separates this cavity within the tympanic region from the auditory canal.

[0009] The first portion of the temporal bone implant is formed as a tube or tube segment, which should be understood, within the scope of the present invention, to mean that the shape of the first portion is designed to be similar to a tube, or similar to a segment formed by subdividing a tube along its longitudinal direction. This shape of the first portion is chosen to achieve the demarcation of the external auditory canal from the space within the temporal bone, and in addition, to form at least one wall portion of the posterior wall of the external auditory canal. Specifically, the shape of the first portion as a tube or tube segment can be configured with different inner diameters and may also be formed as a funnel or funnel segment, depending on the path of the external auditory canal to be reconstructed.

[0010] Preferably, the temporal bone implant has an inner surface that is positioned on the temporal bone and can therefore also be called the bone surface. Opposite the inner surface is the outer surface of the temporal bone implant, on which the auditory canal lies, and this auditory canal is separated by the first part. Therefore, the outer surface within the region of the first part can also be called the auditory canal surface.

[0011] Preferably, the first portion forms a closed septum of the temporal bone implant within the region of the first portion, i.e., no passage is formed between the outer and inner surfaces of the temporal bone implant on the first portion. As a result, when the ear canal is separated from the space by the first portion, fluid from the space can be prevented from reaching the external auditory canal by the first portion. This is because it can increase the risk of recurrent inflammation.

[0012] According to additional independent claim 1, the present invention includes the technical teaching that the first portion transitions into a plate-like second portion oriented laterally to the first portion. The second portion is attached to the mastoid process of the temporal bone and is provided to cover the space together with the first portion. In other words, the first portion thus abuts against the second portion of the temporal bone implant, which is oriented to extend laterally to the first portion and is designed to be similar to a plate. In the temporal bone implant, the second portion is attached to the mastoid process (mastoid) of the temporal bone and is designed to cover the space within the temporal bone together with the first portion.

[0013] Embodiments of the present invention have the advantage that reliable coverage of a cavity within the temporal bone can be achieved by a first portion formed as a tube or tube segment and a second plate-like portion, which is particularly of the type that occurs when a radical mastoidectomy is performed. This is because the first portion can cover a cavity particularly in the tympanic region of the temporal bone, while the second portion can preferably cover a cavity in the mastoid process region of the temporal bone. In addition, the temporal bone implant can be securely attached to the temporal bone, i.e., the remaining portion of the mastoid process of the temporal bone, on the second portion. Furthermore, the first portion can separate the ear canal from the cavity, thereby allowing reconstruction of the posterior bone wall of the external auditory canal. When the first portion forms a closing septum, this is particularly preferable because it at least prevents, and preferably completely prevents, the passage of bodily fluids from the cavity into the ear canal. Thus, as a whole, a temporal bone implant can be realized that is suitable for sealing surgically formed mastoid cavities or radical cavities, and requires minimal aftercare to ensure that the ear canal is separated from the cavity. In particular, as a result, the risk of recurrent inflammation after treatment for cholesteatoma can be reduced.

[0014] The second portion is plate-shaped, which should be understood within the scope of the present invention to mean that the second portion has a substantially flat shape similar to a plate, in that the second portion extends within the coordinate system mainly along two coordinate axes, but may have one or more curvatures to conform to the anatomical structure. The second portion is provided such that the inner surface of the temporal bone implant is attached to the mastoid process of the temporal bone.

[0015] The second portion of the temporal bone implant is provided not only for attachment to the mastoid process but also, together with the first portion, to cover the space within the temporal bone when the temporal bone implant is in use. The first portion is used in particular to cover the space within the tympanic region of the temporal bone, while the second portion is preferably provided to cover the space within the mastoid process region of the temporal bone. Most preferably, the first and second portions of the temporal bone implant are designed to completely cover the space within the temporal bone together.

[0016] Preferably, the first and second parts of the temporal bone implant are formed integrally, thereby forming the temporal bone implant as a single component. Most preferably, the first and second parts are formed in an additive manufacturing process, particularly within the framework of a 3D printing process. Alternatively, however, preferably, the first and second parts are made, in whole or in part, of a metal or metal alloy such as titanium, stainless steel, magnesium, or molybdenum, or a plastic, particularly a polymer such as polyetheretherketone (PEEK), polyethylene (PE), polycaprolactone (PCL), or a ceramic, beta-tricalcium phosphate (β-TCP), zirconia, hydroxyapatite (HA), or a combination of the aforementioned materials. In addition, the two parts may have non-porous surfaces or porous surfaces, or a sub-part of the two parts may be porous and the sub-part may be non-porous.

[0017] According to one embodiment of the present invention, the second portion comprises a mounting portion and a cover portion. The mounting portion forms a contact surface on the inner surface on which the temporal bone implant is positioned on the temporal bone, which comes into contact with the mastoid process for attachment to the mastoid process. The cover portion is provided to cover the void. This ensures that the second portion is securely configured to be attached to the temporal bone and cover the void. Preferably, the mounting portion partially surrounds the cover portion at its periphery so that the temporal bone implant can be attached to the mastoid process at the mounting portion, surrounding the void.

[0018] In an advanced form of the above-described embodiment, multiple receptive openings can be introduced within the attachment portion of the second part, the receptive openings extending from the inner surface to the outer surface of the temporal bone implant facing the opposite side of the inner surface, and used to guide the attachment means through them. Preferably, the temporal bone implant can be attached to the temporal bone through these receptive openings. Preferably, the receptive openings are configured as circular openings, which can be introduced into the attachment portion of the second part as bores by grinding or metal cutting. If the second part is manufactured within the framework of an additive manufacturing process, the receptive openings may also be defined within the framework of additive manufacturing. The attachment means used may be bone screws for screwing the temporal bone implant into the temporal bone, or sutures for suturing to the temporal bone.

[0019] Alternatively or additionally, multiple passages may be introduced within the cover portion, extending from the inner surface to the outer surface of the temporal bone implant facing the opposite side of the inner surface. These passages may be used as suture holes for attaching the skin to the cover portion of the second portion, particularly when the second portion is made of a material that makes tissue growth difficult or impossible.

[0020] According to one possible embodiment of the present invention, a first portion forms a sealing surface on the inner surface of the temporal bone implant, which is positioned on the temporal bone. Therefore, the ear canal can preferably be sealed against the void within the temporal bone. In addition, if a coating is applied to the sealing surface, this is particularly preferred as it enables a particularly reliable seal. This coating may be a flexible material such as porous polyether ether ketone (PEEK), porous polyethylene (PE), or polycaprolactone (PCL). Furthermore, the coating may be optionally designed to be absorbent.

[0021] In the advanced forms of the possible embodiments described above, the sealing surface may be formed at least partially on the periphery of the first portion and provided to seal the ear canal to the gap by contact with the temporal bone. More preferably, to achieve a seal such that the ear canal closes as much as possible when separated from the gap, a continuous attachment to the temporal bone is achieved by the sealing surface within the region of the first portion.

[0022] According to additional possible embodiments of the present invention, the first and second portions are molded in a patient-specific manner. This has the advantage that the first and second portions, and therefore the entire temporal bone implant, are also fitted to the patient's temporal bone. Preferably, the first and second portions model the bone portion to be removed from the patient's temporal bone. In particular, the contour of the temporal bone is determined in advance for this purpose within the framework of a medical imaging process such as CT.

[0023] According to an additional independent claim 11, the present invention also relates to a method for constructing and / or manufacturing a temporal bone implant provided for at least partially repairing the posterior wall of the external auditory canal. In the temporal bone implant, a first portion, formed as a tube or tube segment, is designed to form at least one portion of the posterior wall by covering a cavity within the temporal bone and thereby separating the auditory canal from the cavity. In addition to the first portion, the temporal bone implant comprises a plate-like second portion oriented laterally to the first portion, the second portion being attached to the mastoid process of the temporal bone and designed to cover the cavity together with the first portion.

[0024] Therefore, within the context of the method according to the present invention, the construction or manufacture of a temporal bone implant, or both construction and manufacture, are carried out. "Construction" should be understood to mean, in particular, planning and designing the temporal bone implant, i.e., creating a design or template for manufacturing the temporal bone implant. "Manufacture" is intended to mean the fabrication of the temporal bone implant, i.e., the physical embodiment of the temporal bone implant. In particular, both the construction and manufacture of the temporal bone implant are carried out within the framework of the method according to the present invention. Most preferably, the manufacture is carried out in an additive manufacturing process, in particular by a 3D printing process.

[0025] Therefore, preferably, a temporal bone implant can be constructed and / or manufactured, thereby achieving reliable coverage of the cavity, which is particularly of the type that occurs when a radical mastoidectomy is performed. Furthermore, using the constructed and manufactured temporal bone implant, the auditory canal can be separated from the cavity by the first portion, and thus the posterior bone wall of the auditory canal (external auditory canal bone) can be reconstructed. Thus, as a whole, a temporal bone implant can be realized that is suitable for sealing surgically formed mastoid cavity or radical cavity, and requires minimal aftercare to ensure that the auditory canal is separated from the cavity.

[0026] Preferably, the temporal bone implant is also formed with respect to the configuration and / or creation according to at least one of the above-described variants of the temporal bone implant according to the invention.

[0027] In one development form of the method according to the invention, the first part and the second part can model, in their configuration, the bone segment to be removed from the patient's temporal bone. As a result, a patient-specific adapted temporal bone implant can be achieved. Alternatively, but preferably, furthermore, the first part and the second part are configured according to a predetermined contour of the temporal bone, and this determination is carried out especially within the framework of a medical imaging process such as CT.

[0028] According to an additional possible embodiment of the method according to the invention, a surgical template is also planned and / or manufactured together with the temporal bone implant. Suitably, in this case, this surgical template can be used to perform a radical mastoidectomy, whereby an accurate removal of the segment of the temporal bone can be achieved.

[0029] Preferred embodiments of the invention described below are represented in the drawings.

Brief Description of the Drawings

[0030] [Figure 1] A perspective view of a temporal bone implant according to a preferred embodiment is shown. [Figure 2] A perspective view of a part of the skull within the region of the temporal bone, where the region of the temporal bone to be removed is marked, is shown. [Figure 3] An additional perspective view of the state where a surgical template is applied to the region of the skull of FIGURE 2 is shown. [Figure 4] An additional perspective view of the region of the skull after removing the region of the temporal bone from FIGURE 2 is shown. [Figure 5] A view of the skull after insertion of the temporal bone implant is shown. [Figure 6] Another view of the skull after insertion of the temporal bone implant is shown. [Figure 7] Another diagram of the skull after the insertion of a temporal bone implant is shown. [Modes for carrying out the invention]

[0031] Figure 1 shows a perspective view of a temporal bone implant SI configured according to a preferred embodiment of the present invention. This temporal bone implant SI is manufactured integrally within the framework of an additive manufacturing process, which is carried out by a 3D printing process.

[0032] In this case, the temporal bone implant SI is made of titanium, but alternatively, one other metallic material such as stainless steel or magnesium, a metallic alloy such as titanium alloy, a plastic, especially a polymer such as polyether ether ketone (PEEK), polyethylene (PE), polycaprolactone (PCL), a ceramic, beta-tricalcium phosphate (β-TCP), zirconia, or hydroxyapatite (HA), and combinations of these materials may also be used.

[0033] The temporal bone implant SI consists of a first portion A1 and a second portion A2. The first portion A1 is formed as a tubular segment by designing it to have a curved portion toward the outer surface AS of the temporal bone implant SI. The first portion A1 transitions to the second portion A2, which is oriented laterally to the first portion A1 and is planar.

[0034] The second part A2 comprises a cover portion AT and a mounting portion BT that surrounds the cover portion AT on its outer circumference. The mounting portion is designed with multiple receptive openings AO as circular openings, each of which extends from the outer surface AS to the inner surface IS opposite the outer surface AS of the temporal bone implant SI and completely penetrates the mounting portion BT.

[0035] As is clear from Figure 1, the cover portion AT of the second portion A2 is provided with multiple passages D that completely penetrate the cover portion AT of the second portion A2 from the outer surface AS to the inner surface IS. However, the first portion A1 of the temporal bone implant SI is designed as a solid wall and does not have passages or openings between the outer surface AS and the inner surface IS.

[0036] The temporal bone implant SI shown in Figure 1 is configured and manufactured for an actual patient-specific use in the temporal bone SB region of skull S. For this purpose, the shape of this skull S was pre-determined by a medical imaging process, particularly by CT, taking into account the 3D model of skull S partially shown in each of Figures 2 to 7. The temporal bone implant SI is declared to be the region of the temporal bone SB of skull S to be removed within the framework of radical mastoidectomy, and is formed in a patient-specific manner by constituting two parts A1 and A2 of the temporal bone implant SI according to the bone parts KA1 and KA2, which are shaded in Figure 2. Radical mastoidectomy should be performed to allow for the complete removal of the cholesteatoma, particularly in the region of the external auditory canal GG.

[0037] In this case, the bone portion KA1 to be removed is part of the mastoid process (mastoid) of the temporal bone SB, while the bone portion KA2 to be removed is part of the tympanic portion (pars tympanica) of the temporal bone SB and forms part of the posterior bone wall W of the external auditory canal GG.

[0038] Figure 3 shows the skull S with a surgical template OS applied, which, together with the temporal bone implant SI, is constructed in a patient-specific manner based on the determined shape of the skull S. As is evident from Figure 3, the surgical template OS is designed to be attached to the temporal bone SB and defines the bone portions KA1 and KA2 to be removed as a sawing and drilling template. Furthermore, Figure 4 shows the skull S after the removal of bone portions KA1 and KA2, thereby creating a space FS within the temporal bone SB. Due to the fact that bone portion KA1 forms part of the mastoid process and bone portion KA2 forms part of the tympanic region, the space FS has space FS1 in the mastoid region and space FS2 in the tympanic region, the latter of which removes part of wall W.

[0039] Figures 5 to 7 show a skull S with a temporal bone implant SI positioned on the temporal bone SB, and the attachment portion BT of the second part A2 of the temporal bone implant positioned on the mastoid process of the temporal bone SB. As is particularly clear when referring to Figure 6, this positioning is performed on the inner surface IS of the temporal bone implant SI, at the contact surface AF on which the attachment portion BT is mounted on the inner surface IS. The temporal bone implant SI can be attached to the temporal bone SB at the receiving opening AO of the attachment portion BT, and for this purpose, corresponding attachment means (not shown) need to be guided through the receiving opening AO. In the context of the present invention, these attachment means may be bone screws for screwing into the temporal bone SB or sutures for suturing to the temporal bone SB. In addition, multiple passages D within the cover portion AT can be used as suture holes for suturing the temporal bone implant SI to tissue, particularly skin.

[0040] The void FS1 is covered by the cover portion AT of the second portion A2, while the first portion A1 covers the void FS2, thereby also forming the wall portion WA of the posterior wall W. As a result, the first portion A1 separates the external auditory canal GG from the void FS. Complete coverage of the void FS is also achieved by the two portions A1 and A2.

[0041] As is clear from the detailed view in Figure 7, the first portion A1 forms a sealing surface DF on the inner surface IS of its peripheral edge, and on the sealing surface DF, the first portion A1 peripherally abuts against the temporal bone SB at the outer edge of the gap FS2, thereby sealing the external auditory canal GG to the gap FS. This peripheral contact and the solid wall embodiment of the first portion A1 prevents bodily fluids from entering the external auditory canal GG through the gap FS by the temporal bone implant SI. To further improve the sealing performance, the first portion A1 may also be provided with a coating on the sealing surface DF.

[0042] Therefore, embodiments of the present invention provide a temporal bone implant that enables the repair of the posterior wall of the external auditory canal with minimal aftercare required. [Explanation of Symbols]

[0043] SI...Temporal bone implant, A1...First part, A2...Second part, AS...Outer surface, AT...Cover part, BT...Attachment part, AO...Receptor opening, IS...Inner surface, D...Passage, SB...Temporal bone, S...Skull, KA1...Bone part, KA2...Bone part, GG...External auditory canal, W...Wall, OS...Surgical template, FS...Gap, FS1, FS2...Gap part, AF...Contact surface, WA...Wall part, DF...Sealing surface.

Claims

1. A temporal bone implant (SI) provided for at least partially repairing the posterior wall (W) of the external auditory canal (GG), comprising a first portion (A1) shaped as a tube or tube segment and designed to form at least one wall portion (WA) of the posterior wall (W) by covering a space (FS) within the temporal bone (SB), thereby separating the auditory canal (GG) from the space (FS), wherein the first portion (A1) transitions into a plate-shaped second portion (A2) oriented laterally to the first portion (A1), the second portion (A2) being attached to the mastoid process of the temporal bone (SB) and provided together with the first portion (A1) to cover the space (FS).

2. The temporal bone implant (SI) according to claim 1, wherein the second portion (A2) comprises a mounting portion (BT) and a cover portion (AT), the mounting portion (BT) having a contact surface (AF) on the inner surface (IS) where the temporal bone implant (SI) is positioned on the temporal bone (SB) that comes into contact with the mastoid process for attachment to the mastoid process, and the cover portion (AT) being provided to at least partially cover the void (FS).

3. The temporal bone implant (SI) according to claim 2, characterized in that the mounting portion (BT) partially surrounds the cover portion (AT) at its periphery.

4. The temporal bone implant (SI) according to claim 2 or 3, characterized in that a plurality of receiving openings (AO) are introduced into the mounting portion (BT) of the second portion (A2), and the plurality of receiving openings (AO) extend from the inner surface (IS) to the outer surface (AS) of the temporal bone implant (SI) facing away from the inner surface (IS), and are used to guide the mounting means.

5. A temporal bone implant (SI) according to at least one of claims 2 to 4, characterized in that multiple passages are introduced within the cover portion (AT) extending from the inner surface (IS) to the outer surface (AS) of the temporal bone implant (SI) facing the opposite side of the inner surface (IS).

6. The temporal bone implant (SI) according to at least one of claims 1 to 5, characterized in that the first portion (A1) forms a sealing surface (DF) on the inner surface (IS) where the temporal bone implant (SI) is positioned on the temporal bone (SB), such that it is positioned on the temporal bone (SB).

7. The temporal bone implant (SI) according to claim 6, characterized in that the coating is applied to the sealing surface (DF).

8. The temporal bone implant (SI) according to claim 6 or 7, characterized in that the sealing surface (DF) is at least partially formed on the periphery of the first portion (A1) and is provided to seal the ear canal (GG) to the gap (FS) by contact with the temporal bone (SB).

9. A temporal bone implant (SI) according to at least one of claims 1 to 8, characterized in that the first portion (A1) and the second portion (A2) are molded in a manner specific to the patient.

10. The temporal bone implant (SI) according to claim 9, characterized in that the first portion (A1) and the second portion (A2) are modeled after the bone portions (KA1, KA2) to be removed from the patient's temporal bone (SB).

11. A method for constructing and / or manufacturing a temporal bone implant (SI) provided for at least partial repair of the posterior wall (W) of the external auditory canal (GG), wherein the temporal bone implant (SI) is designed to form at least a portion of the posterior wall (W) by covering a space (FS) within the temporal bone (SB), thereby separating the auditory canal (GG) from the space (FS), and the temporal bone implant (SI) comprises, in addition to the first portion (A1), a plate-like second portion (A2) oriented laterally to the first portion (A1), wherein the second portion (A2) is attached to the mastoid process of the temporal bone (SB) and is designed to cover the space (FS) together with the first portion (A1).

12. The method according to claim 11, characterized in that the temporal bone implant (SI) is further configured according to any one of claims 2 to 10.

13. The method according to claim 11 or 12, characterized in that the first portion (A1) and / or the second portion (A2) are modeled after bone portions (KA1, KA2) to be removed from the patient's temporal bone (SB) during construction.

14. The method according to at least one of claims 11 to 13, characterized in that the configuration of the first portion (A1) and the second portion (A2) is carried out based on a predetermined contour of the temporal bone (SB).

15. The method according to at least one of claims 11 to 14, characterized in that the surgical template (OS) is also planned and / or manufactured together with the temporal bone implant (SI).

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