Dental implant arrangement

Description

[0001] The present invention relates to the field of dentistry and describes a dental implant assembly that is inserted into a patient's jawbone. The dental implant assembly according to the invention serves to receive a crown, a dental prosthesis. The dental implant assembly comprises a base body that connects the dental implant assembly to the alveolar bone (i.e., the jawbone), an abutment, and a connecting element. The abutment serves as a two-sided adapter that connects the dental prosthesis, the crown, to the dental implant assembly. The abutment is attached to the base body by means of the connecting element.

[0002] One- or two-piece dental implants are known from the prior art. These extend along a first longitudinal axis between an apical and a coronal end, and the apical, endosseous part of the dental implant, the base body, is designed to be embedded in the patient's jawbone.

[0003] Dental implantology involves the restoration of one or more teeth in a patient's mouth using artificial components. These artificial components typically consist of a dental implant and a prosthetic crown firmly attached to the dental implant. The dental implant can be a one-piece element with an integrated connector to the dental crown. In recent years, two-piece dental implant systems have become established. A two-piece dental implant typically consists of a base body that is anchored in the bone and an abutment that acts as a connector between the artificial tooth crown and the base body of the dental implant. The base body is usually implanted by raising a soft tissue flap and drilling into the alveolar bone to prepare the bed for the dental implant.The base body is then inserted, a cap is attached to support the wound healing process, and the wound is then appropriately closed. After the healing process, the cap is removed, and the abutment is screwed to the base body and / or cemented with a suitable bonding agent. The prosthetic tooth, the artificial tooth crown, can then be placed in place.

[0004] There are dental implants that are fully embedded in the bone and are flush with the bone level (juxta-osseous placement) or even slightly below it. These dental implants are called "bone-level" implants. These implants typically require a two-stage surgical procedure. An implant whose shoulder extends a few millimeters above the bone level, thus contributing to the shaping of the surrounding tissue, is called a "tissue-level" implant.

[0005] The tissue-level implant has an extended apical portion, a collar that contacts the gingival (soft) tissue. These tissue-level implants allow the dental implant to be placed in a single surgical procedure and are therefore most commonly used for posterior implant sites.

[0006] In most dental implants, the surfaces of the base body and the abutment that meet when implanted are designed to fit together seamlessly and prevent rotation, similar to a plug and socket. To ensure a secure fit of the dental crown, a precisely positioned, non-rotating connection between the two parts must be ensured. The abutment often has a recess, a countersunk hole, along the abutment's longitudinal axis. This recess serves to accommodate a connecting device.

[0007] Titanium alloys are typically used for the manufacture of dental implants because these metals can be easily machined with the high precision required for the very small dimensions of dental implants. Furthermore, due to their plastic compliance, titanium alloys offer good mechanical stability and tightness of the connection, as they tolerate possible local stress concentrations.

[0008] However, the use of titanium alloys as a material for dental implants also has disadvantages. Firstly, the aesthetic aspect of the gray color, which may be visible at the gum line. Secondly, the release of metal ions and the resulting allergic reactions in patients is becoming an increasing problem in dental implantology. These disadvantages, along with recent advances in ceramic materials, have recently led to further developments in ceramic dental implants.

[0009] A variety of two-part, ceramic implants consisting of a base body and an abutment have been proposed. Some of them, as described in DE 21 2013 000 248 U1, use a conical connection and a screw between the base body and the abutment, but in combination with a polymer cement at the interface. This prevents direct ceramic-to-ceramic contact between the mating parts. WO 2018 / 046 148 A1, on the other hand, proposes a ceramic-to-ceramic connection in combination with a plastic screw. US 2006 / 216672 A1, DE 202 09 170 U1, DE 20 2006 013 267 U1, and EP 3 143 961 A1 also propose two-part implants consisting of an implantable base body and a subsequently insertable abutment.

[0010] There are prior art concerns regarding two-piece dental implants where a ceramic base is in contact with a ceramic abutment. Under load, e.g. during chewing, interfaces between the base and abutment may change, for example, open or a gap may develop. These changes can potentially increase the point load beyond the acceptable stress level, potentially causing microcracks and / or failure of the dental implant. The base-abutment interface continues to pose a mechanical challenge for a ceramic-on-ceramic solution. Some of these include: dimensional limitations to accommodate necessary features such as threads, locking or anti-rotation, and reduced mechanical stability.

[0011] In view of the state of the art, the object of the present invention was to provide an improved two-part dental implant that includes a secure, positionally accurate interface and is easy to use.

[0012] This object is achieved by a dental implant arrangement according to claim 1, and by a dental kit according to claim 14. The subclaims specify preferred embodiments. Embodiments can be freely combined with one another. The dental implant arrangement according to the invention comprises a base body and an abutment with an interface matching the base body, as well as a connecting means which holds the base body and abutment in a form-fitting connection with one another. The base body forms the artificial tooth root. It is implanted in the alveolar bone. The base body comprises a shaft section which is located at the apical end of the base body, i.e. the end which is inserted into the alveolar bone, a coupling section at the coronal end of the base body, and a recess which extends inside the base body from the coupling section in the direction of the shaft section.

[0013] When implanted, the abutment is connected to a prosthesis, artificial crown or denture at its upper, coronal part and sits with its lower, apical part on the coronal end of the base body.

[0014] In one embodiment, the abutment itself has the connecting element (hereinafter referred to as internal connecting element), i.e. the abutment is extended in the apical region in such a way that it reaches into the recess of the base body and the abutment is additionally anchored there.

[0015] In a preferred embodiment, the connecting element is not attached to the abutment. The abutment has an opening that extends through the abutment from its upper, coronal part to its lower, apical part. An external connecting element is inserted through this opening, which secures the abutment to the base body. The external connecting element is inserted through the opening of the abutment into the recess of the base body.

[0016] The lower, apical part, the coupling area of ​​the abutment, and the coronal end of the base body, the coupling area of ​​the base body, have a mating, form-fitting interface. The coupling area of ​​the abutment has a geometric shape that is opposite to the geometric shape of the coupling area of ​​the coupling section. In certain areas of the interface, the geometry in the coupling area of ​​the abutment is congruent with the geometry in the coupling area of ​​the base body. The coupling area of ​​the abutment is designed to be received by the coupling area of ​​the base body. When assembled, the coupling area of ​​the lower part of the abutment is connected to the coupling area of ​​the coupling section of the base body, forming a contact line.

[0017] In one embodiment of the invention, the dental implant assembly is a "tissue-level" implant, so that the outer surface of the base body is only partially implanted into the alveolar bone, and the coupling region of the implant protrudes at least partially above bone level. In another embodiment, the implant is designed as a "bone-level" implant for complete embedding in the bone, which is why the outer surface of the base body is completely implanted into the alveolar bone.

[0018] In one embodiment, the base body is 5-30 mm long along the longitudinal axis, with the length being the maximum extension along the longitudinal axis. The base body is preferably 7-25 mm long, particularly preferably 10-20 mm long. So-called short base bodies are 5-10 mm long, and long base bodies are over 25 mm.

[0019] The nominal diameter of the base body is defined as the maximum cross-section of the coupling section of the base body. This is preferably located at the level of the bone / gingiva. The nominal diameter of the base body is particularly preferably located directly below the coupling area. The nominal diameter is preferably in a range of up to 8 mm, preferably up to 6 mm and particularly preferably up to 5 mm. The nominal diameter is further preferably greater than 1 mm, particularly preferably greater than 2 mm. Depending on the shape of the coupling section (cylindrical, elliptical, etc.), the diameter can be uniformly constant or vary over the circumference of the coupling section. The center point of the nominal diameter is preferably on the longitudinal axis. The external design of the base body preferably combines conical, cylindrical and / or threaded sections. The coronal end of the base body is preferably conical or cylindrical.Furthermore, the apical end of the base body is preferably conically shaped and preferably carries at least one threaded section and / or an at least partially porous outer surface.

[0020] In one embodiment, the abutment is 3 - 10 mm, preferably 5 - 9, particularly preferably 4 - 8 mm long in the direction of the longitudinal axis.

[0021] To enable an anatomical restoration of the teeth, the abutment may have a shape that deviates from a cylindrical longitudinal shape. The abutment may have an angularly arranged section relative to its longitudinal axis.

[0022] The diameter of the abutment preferably varies along the longitudinal axis of the implant. The maximum diameter of the abutment is preferably in a range of up to 8 mm, particularly preferably up to 6 mm, and especially preferably up to 5 mm. In a preferred embodiment, the maximum diameter of the abutment is greater than 1 mm, and in a particularly preferred embodiment, greater than 2 mm. The outer shape of the abutment is preferably conical or cylindrical, or at least partially conical or cylindrical.

[0023] In a preferred embodiment, the maximum diameter of the abutment is located directly above the coupling area of ​​the abutment at the apical end of the abutment

[0024] The diameter of the apical part of the abutment can correspond to the diameter of the coronal part of the base body, but it can also be larger or smaller. In one embodiment, the diameter of the apical part of the abutment corresponds to the diameter of the coronal part of the base body or is slightly larger or smaller, whereby the difference between the two diameters is ≤ 10%, preferably ≤ 5%, even more preferably ≤ 1%, so that the base body and abutment have the smoothest possible transition of the outer surface in the area of ​​the interface in the assembled state, without abrupt changes in diameter. The maximum diameter of the apical region of the abutment, the geometry to be connected to the base body, preferably has the same external shape, e.g. cylindrical, as the coupling section of the base body, in order to ensure a smooth and, if possible, uninterrupted outer surface of the entire implant.Depending on the shape of the coupling section of the base body, the diameter of the abutment can also be uniformly constant or vary around its circumference in order to create an interface that fits the coupling area of ​​the base body.

[0025] Possible sizes and shapes of the outer shape of the base body and the abutment are known from the state of the art (e.g., cylindrical with a circular or elliptical base, conical). Two-dimensional geometric shapes without corners, such as circles and ellipses, are preferred.

[0026] The shaft section of the base body extends along the longitudinal axis of the base body. It preferably becomes wider from the apical to the coronal part along the longitudinal axis. The diameter at the apical end is preferably smaller than the diameter at the coronal end. In a preferred embodiment, the shape of the coupling section is cylindrical, cylindrically elliptical, or conical, with segments of different geometries alternating along the longitudinal axis. The shaft section can be made of a dense ceramic and have a wound (threaded), porous, foamed, or rough surface on the outer surface. The outer surface preferably has a roughness Ra of 0.2 to 1.6 µm, more preferably 0.5 to 0.8 µm, to ensure good adhesion of the bone cells and the gingival tissue. The roughness of the outer surface can be achieved by sandblasting or etching the body part of the base body.The outer surface can also have at least one thread and / or pores. The thread preferably protrudes 0.2 to 1 mm, more preferably 0.5 to 0.8 mm, from the surface of the shaft portion. If the shaft portion has a porous outer surface, the pores have an average diameter of 0.2 to 1 mm, preferably 0.5 to 0.8 mm. A porous outer surface of the body part can additionally be provided with a thread, and a threaded outer surface of the body part can carry one or more porous portions. Pores and threads lead to improved hold of the shaft portion in the bone, as cells can grow around and into these structures.

[0027] In one embodiment, the shaft portion is provided with an external thread extending from the apical end toward the coronal end and covering at least parts of the outer surface of the base body.

[0028] The porous outer surface is preferably made of a ceramic foam.

[0029] The coupling section of the main body also extends along the longitudinal axis of the main body and represents the coronal end of the main body.

[0030] The coupling section can be cylindrical with a circular or elliptical base and have conical segments. The coupling section of the base body is preferably cylindrical or conical; more preferably, the coupling section is cylindrical with a circular base. The coupling section can be made of a dense (> 95%, preferably > 99% of the theoretical density) ceramic and can have a porous, foamed, or rough surface on the outer surface. The outer surface preferably has a roughness Ra of 0.2 to 1.6 µm, more preferably 0.5 to 0.8 µm, to ensure good adhesion of the bone cells and the gingival tissue. The roughness of the outer surface can be achieved by sandblasting or etching the coupling section. The outer surface of the coupling section can have threads and / or pores, as described for the shaft section.

[0031] The abutment also extends along the longitudinal axis. The shape of the abutment can be conical or cylindrical with a circular or elliptical base. Segments of different geometries can alternate. The abutment can be made of a dense ceramic and have a porous, foamed, or rough surface on the outer surface. The coronal end of the abutment has features known from the state of the art to ensure a connection to the dental prosthesis, the crown.

[0032] Both the base body and the abutment can be made of titanium, titanium alloy, polymers, or ceramic. Preferred polymers are PE, PEK, PEKK, PEEK, or CFRP-PEEK; fiber-reinforced polymers from the aforementioned list are particularly preferred. The base body and / or the abutment are preferably made of ceramic, particularly preferably zirconium dioxide or zirconium dioxide alloys, such as yttria-stabilized zirconium dioxide (Y-TZP) or aluminum oxide-prestressed zirconium dioxide (ATZ) or cerium oxide-stabilized zirconium dioxide. In a preferred embodiment, the base body and the abutment are made of the same material.

[0033] The abutment and the base body are positioned one above the other in the implanted state, with the lower end, the apical end of the abutment, and the coronal end of the base body forming the matching interface and being in contact with one another. The implant is secured with a connecting element. The base body has a recess into which the connecting element is inserted. The recess, a bore, a cavity, extends through the coupling section from the coronal end of the base body towards the shaft section of the base body. Preferably, the recess extends into the shaft section of the base body. In a preferred embodiment, the recess is a central cutout located in the middle of the base body and extending along the longitudinal axis from the coronal end towards the apical end. Preferably, the recess has a cylindrical part at the coronal end of the base body.More preferably, the cylindrical axis is part of the longitudinal axis of the base body. The cylinder is preferably a rectangular cylinder with a circular base, but can also have an elliptical or otherwise non-circular base. The recess extends partially into the shaft section. The shaft section is closed at the apical end of the base body. In a preferred embodiment, the recess extends over a maximum of 3 / 4 of the total length of the base body in the direction of the shaft section of the base body. 1 / 4 of the length of the base body at the apical end is solid, i.e. the recess ends before this section of the base body. The recess, the bore, can further comprise a threaded section on the inside, which is preferably arranged in the apical end of the recess.An internal connection recess, which has an internally threaded section, is designed to receive a connecting element which is used to secure the abutment mounted on the base body.

[0034] The minimum wall thickness around the recess in the interior of the base body is preferably ≥ 0.65 mm, more preferably a wall thickness ≥ 0.8 mm, particularly preferably a wall thickness ≥ 1 mm.

[0035] The coupling section is located at the coronal end, the upper region of the base body. The coupling section of the base body comprises a coupling region located between the outer surface of the base body and the recess. The coupling region comprises the region between the edge of the outer surface of the base body, the outer transition region, and the edge in the opening into the interior of the base body, the inner transition region, and encloses the recess. Preferably, the edge extending into the recess and / or the edge extending towards the outer surface of the base body is rounded to prevent wear and damage to the coupling region. This surface of the coupling region is preferably precision machined to tolerances of less than 0.05 mm and can be fired, ground, or polished.

[0036] The coupling area is concavely or convexly curved. The radii with which the edges are rounded, as well as the radius of the coupling area, which is concavely or convexly shaped, can be the same or different, depending on the design. Preferably, the radii of the inner and outer transition areas, as well as the central section, are uniformly constant along the coupling area around the recess and have no interruptions. This results in the same radius being present at every point in the coupling area.

[0037] In a preferred embodiment, the coupling region of the base body is concave, and the radii of the transition regions merge tangentially into the coupling region. This creates a concave surface with continuously merging radii.

[0038] In one embodiment, the rounded transition areas extend in such a way that they meet the inner and outer surfaces, ie a completely rounded coupling area is created without edges or step-like transitions.

[0039] The convex coupling area of ​​the coupling section of the base body is referred to as the male part. The apical end of the abutment, with its concave coupling area, is provided with a matching female part. The two parts form the matching interface.

[0040] The male coupling area at the coronal end of the base body is intended to be received by the female coupling area of ​​the apical end of the abutment.

[0041] At the bottom of the abutment, the end that meets the base body when assembled, is the concave coupling area, part of the interface. The coupling area of ​​the abutment is located between the outer transition area, the outer surface of the abutment, and the inner transition area, the opening for an external connecting element. If the abutment has an integrated connecting element, the inner transition area is located between the coupling area and the integrated connecting element.

[0042] The inner and outer transition areas on the abutment side are also preferably rounded to prevent wear and damage to the abutment. The coupling area of ​​the abutment extends between the inner and outer transition areas. This area can be concave or convex, opposite to the shape of the coupling area of ​​the base body. A convex coupling area of ​​the base body fits to a concave coupling area of ​​the abutment and vice versa. The radii with which the transition areas are rounded, as well as the radius of the coupling area, which is concave or convex, can be the same or different. Preferably, the radii of the inner and outer transition areas, as well as of the coupling area, are uniformly constant along the course of the coupling area around the opening or connecting element and have no interruptions.

[0043] The geometric shape of the abutment's coupling area is adapted to the geometric shape of the base body's coupling area and follows its design. If the geometric shape of the base body's coupling area is uniformly formed over the circumference of the base body, the geometric shape of the abutment's coupling area is also uniformly formed over the circumference of the abutment.

[0044] The convex coupling area of ​​the abutment and the concave coupling area of ​​the base body form the interface. The coupling areas of the base body and the abutment, which are convex and concave respectively, touch each other and form a contact line. The contact line is created because the two intersecting coupling areas are curved, with the convex coupling area having a greater curvature than the concave coupling area. The two coupling areas are designed such that a contact line is created after the base body and the abutment have been joined together. The interface according to the invention leads to a contact line after assembly. This avoids individual contact points where peak loads can occur.

[0045] In the plan view along the longitudinal axis, the contact line appears circular, elliptical, hyperbolic or it corresponds to an edge-free free form, an irregular ellipse or an irregular circle. The contact line is preferably circular or at least approximately circular (within the manufacturing tolerances) or regularly elliptical. Preferably, when both coupling areas are in contact with each other, they form a closed contact line, i.e. within the coupling areas the base body and the abutment meet and form a closed contact line which, with the exception of manufacturing tolerances, has no intentional interruptions, e.g. due to recesses or notches within a coupling area. The manufacturing tolerances can lead to minimal deviations and discrepancies within the closed contact line.In a preferred embodiment, the contact line is circular or at least approximately circular (within manufacturing tolerances). This facilitates the manufacture and insertion of the implant. Furthermore, a circular contact line also leads to self-centering of the abutment relative to the base body.

[0046] In the preferred embodiment, the diameter of the contact line in plan view, i.e., when the contact line is projected into a plane, is 99%-40% of the nominal diameter of the base body. The nominal diameter of the base body is the maximum diameter of the coupling section of the base body. Preferably, the diameter of the contact line is 95%-65%, preferably 90%-80% of the nominal diameter of the base body.

[0047] In one embodiment, the concave and / or convex coupling areas of the abutment and base body are free-form curves that do not run parallel to one another. The concave coupling area is slightly less curved than the convex coupling area. This ensures that the convex coupling area fits into the space formed by the concave coupling area. When the abutment and base body are assembled, the aforementioned coupling areas are arranged at a distance from one another at their ends, at the inner and outer transition areas. The distance reduces, starting from the inner and outer transition areas towards the center of the coupling areas, where they are in contact in the assembled state. This creates the contact line. In another embodiment, the concave and convex coupling areas are hyperbolic or diametrical parts of an ellipse.

[0048] In one embodiment, the difference in the bend, the curvature of the concave or convex regions, over the distance from the inner to the outer transition region of the two bent or curved coupling regions is at least twice the manufacturing tolerance (preferably the manufacturing tolerance is a maximum of 0.05 mm), preferably at least five times the manufacturing tolerance, with the concave coupling region being less curved or curved than the convex coupling region. This ensures linear contact between the coupling regions. According to the invention, the geometric shapes of the coupling regions of the abutment and the base body are designed differently. The geometric shapes deviate from one another at least to the extent that linear contact occurs in the assembled state. It is irrelevant whether the deviations in the geometric shape of the coupling regions arise from the design or from tolerances during production.If the difference between the bends of the coupling areas is too small, surface contact may occur instead of line contact. The properties, e.g., the force input, of a surface contact are different from those of a line contact and are disadvantageous for the safe, long-term use of the interface. A line contact is provided for an implant made of ceramic materials according to the invention.

[0049] In a preferred embodiment, both the concave and the convex coupling region are a circular segment in cross-section. The center of the circle corresponding to the circular segment forming the concave coupling region lies within the part encompassing the convex coupling region. The center of the circle corresponding to the circular segment forming the convex coupling region lies within an imaginary extension of the part encompassing the concave coupling region. Both circular segments have a radius. The radius of the circle forming the concave coupling region is 0.1-10%, preferably 1-5%, larger than the radius of the circle forming the convex coupling region. In a preferred embodiment, the radius of the convex coupling region is in the range of 10 to 50% of the nominal diameter of the base body.

[0050] When assembled, the opposite ends of the coupling regions are arranged at a distance from one another. This distance is present at the outer and one at the inner transition region of the coupling regions. This distance and, as a result, the gap formed thereby are preferably as small as possible. This is achieved by the convex coupling region being only slightly more curved than the concave coupling region. According to the invention, the coupling regions are designed such that, when the abutments and the base body are assembled, a contact line is created, with the distance between the coupling regions in the transition region, i.e. in the end regions of the coupling regions, being as small as possible. In a design with circular geometries as concave and convex coupling regions, this is achieved by the nominal radii of the convex and concave coupling regions deviating only slightly from one another.The radius of the convex coupling region must be smaller than the radius of the concave coupling region to ensure that the convex coupling region fits into the space formed by the concave coupling region. The ratio of convex radius to concave radius is preferably 0.8 - 0.999:1, more preferably 0.9 - 0.98:1, and particularly preferably 0.94 - 0.96:1. In one embodiment, the difference between the two radii is 5 times the manufacturing tolerance (e.g., 0.05 mm), preferably 10 times the manufacturing tolerance, with the concave radius being larger than the convex radius to ensure line contact.

[0051] The interface according to the invention, consisting of a convex and a concave coupling region, as described above, is advantageous regardless of parameters that exist during the manufacture of ceramic products, such as shrinkage during sintering and / or material removal during polishing. The two coupling regions designed according to the invention always form a line contact. With a circular circumference of the central parts of a coupling region, the contact line will form a circle in plan view. This circle encloses the recess of the base body and the opening or connecting element of the abutment. This interface according to the invention protects the coupling areas and thus the abutment and the base body from tension and stress, ensures self-centering of the two touching parts.

[0052] In one embodiment, the interface according to the invention is arranged symmetrically around the longitudinal axis of the dental implant arrangement. The contact line, formed by the convex and concave coupling areas, lies in a single plane. This plane can be perpendicular or at an angle to the longitudinal axis.

[0053] In another embodiment, the contact line between the abutment and the base body of the interface according to the invention is arranged at a distance in at least one region with respect to a plane that is oriented perpendicular to the longitudinal axis of the dental implant arrangement. This means that the contact line has at least one valley, a depression, and at least one peak, a protrusion relative to this plane. A depression in the coupling region of the base body lies opposite a protrusion in the coupling region of the abutment. The deepest point of a depression in the coupling region of the base body represents the point of maximum distance of the convex or concave coupling region that intersects a plane perpendicular to the longitudinal axis that lies further towards the apical end of the base body than the planes that intersect the nearest points on either side of the course of the coupling regions.The highest point of a protrusion is the opposite of a depression and represents the point of maximum distance of the convex or concave coupling area that intersects a plane perpendicular to the longitudinal axis that lies further toward the coronal end of the base body than the planes intersecting the nearest points on either side of the coupling area. The same applies, mutatis mutandis, to a protrusion or depression of the abutment's coupling area. The deepest or highest point of a depression or protrusion thus represents a vertex.

[0054] In a design with a raised portion and a recessed portion, the contact line is arranged at an angle to the longitudinal axis. Due to the angular contact line and the resulting potential shear forces, a stable connection between the abutment and the base body requires that the connecting element, preferably the screw, be at least 1.5 times its diameter.

[0055] In a preferred embodiment, the profile of the coupling region has more than one depression and elevation, preferably 2, 3 or 4 depressions and elevations. An even number of depressions and elevations is further preferred. In a preferred embodiment, the distances between the depressions and elevations of the coupling region are symmetrical, i.e. the distance between each depression and the following elevation (and vice versa) is the same. In one embodiment, the coupling region of the base body has a first elevation, a second elevation and a first depression between the first elevation and the second elevation as well as a second depression between the second elevation and the first elevation, and the elevations and depressions are preferably diametrically opposite one another. The same applies mutatis mutandis to the abutment, provided that the geometry matches the base body.

[0056] In a particularly preferred embodiment, the coupling region has two depressions and two elevations and is preferably designed symmetrically, i.e. the depressions and elevations are arranged opposite one another in the coupling region. A coupling region designed in this way functions both as an anti-twist device and as a self-locking element. During assembly, as soon as the depressions and elevations of the base body and the abutment are aligned, a connecting element is inserted through the opening of the abutment into the recess of the base body and fastened inside the base body. Once the connecting element has been fastened, rotation of the abutment on the base body is impossible because the coupling region requires a vertical displacement of the abutment for rotational movement, i.e. the abutment must move upwards to compensate for the depressions and elevations and enable rotation.This height shift is prevented by the connecting element. Furthermore, during assembly, the abutment is moved radially on the base body until the elevations and depressions interlock, i.e., a projection of one coupling area "clicks" into a depression of the other coupling area. In the prior art, the connecting element serves not only for fastening, but also to prevent rotation and therefore often has a non-circular outer shape. In an inventive arrangement of the above-described designs with elevations and depressions, the anti-rotation feature is ensured solely by the shape of the coupling area. The connecting element merely has the task of securing the abutment and base body. The connecting element does not need to have an additional anti-rotation feature. Therefore, the connecting element, preferably a screw, can have a circular cross-section of the outer shape, i.e.a conical or cylindrical screw body, preferably with a thread. This design allows the connecting element to be formed in a stable shape with a maximum diameter. By using a connecting element with a maximum diameter, a higher preload and thus greater bending strength and stability can be achieved.

[0057] A fastener with an anti-twist feature has a circumferential reduction at at least one location. This reduces the cross-section compared to a circular cross-section, resulting in an overall reduction in the stability of the fastener.

[0058] In a further preferred embodiment, the depressions and elevations mimic the natural gum line so that the appearance in the implanted state is aesthetically pleasing. In a preferred embodiment, the artificial tooth or crown can then only be attached to the abutment and does not have to cover the base body. If the base body is placed in the jawbone, the course of the gum is not changed or modified by it and a natural appearance is retained. In such a configuration, the at least two depressions do not lie on a plane that is arranged perpendicular to the longitudinal axis. The planes on which the depressions lie are arranged at a distance from one another. One plane is arranged further towards the apical end than the other plane.If there are two elevations and two depressions, the apex of the first depression of the coupling region of the base body is more coronal than the apex of the second depression. In another embodiment, the apex of the first elevation is more apical than the apex of the second elevation. The arrangement of the apex points can be according to requirements. All apex points can be spaced apart with respect to the longitudinal axis of the dental implant arrangement. In this case, all apex points lie on mutually spaced planes perpendicular to the longitudinal axis. The same applies mutatis mutandis to the elevations and to the course of the coupling region of the abutment. Coupling regions of the base body and abutment according to the invention are designed to form a positive fit with respect to one another and to engage with one another when implanted. Therefore, an uninterrupted contact line is formed between the abutment and the base body when mounted.If the lowest vertex is located on the buccal side when implanted, an aesthetically pleasing facial anterior aspect can be ensured. If the oral side is also adapted to the natural gum line, a dental implant arrangement according to the invention naturally reflects the conditions. This means the least possible irritation for the patient, ideally none at all.

[0059] The difference between the individual depressions and elevations is preferably 0.1-2 mm, more preferably 0.3-1 mm, and particularly preferably 0.3-0.5 mm. In one embodiment, the ratio between the distance between adjacent vertices, i.e., between a depression and the elevations located in direct proximity, and the diameter of the contact line is 0.025 to 0.5:1.

[0060] Preferably, the course between the vertices is smooth and curved, i.e. without sharp edges or steps.

[0061] The abutment is attached to the base body with a connecting element. The connecting element can be an internal connecting element already attached to the abutment, which is enclosed by the coupling area and protrudes beyond it in such a way that it can be inserted into the recess of the base body and secured there. Preferably, an internal connecting element is secured in the recess using additional adhesives, dental fasteners such as adhesives or cement.

[0062] In a preferred embodiment, the connecting element is not attached to the abutment. It is an external connecting element. The abutment has an opening for the passage of a connecting element, which extends through the abutment from the apical to the coronal part. The external connecting element is preferably a screw that is screwed into a threaded section of the recess in the base body. The opening of the abutment contains holding means that are matched to the connecting element in order to ensure a firm fit and secure attachment of the abutment. Preferably, one or more projections are located within the opening, which project from the wall of the abutment into the opening. In the assembled state, this at least one projection is in contact with one area of ​​the external connecting element, e.g. the screw head.Preferably, the projection is angled to ensure maximum contact area between the connecting element region and the abutment. In a preferred embodiment, the projection is conical. The projection extends from the coronal portion of the abutment to the apical portion of the abutment and decreases the diameter of the opening toward the apical portion.

[0063] In a preferred embodiment, the head of the external connecting element and the corresponding retaining elements, preferably the projections, of the abutment form a circular contact line near the shaft of the connecting element. This makes it possible to increase the insertion torque required to secure the fastening element. Such a contact line can be achieved by conical projections in the opening of the abutment and a convex radius of the head of the external connecting element, preferably the screw head. The above-described geometric shape, the conical projection, can alternatively be provided on the connecting element. In this case, the convex radius is arranged on the projection of the abutment. Regardless of the arrangement of the above-described geometric shapes, a circular contact line between the connecting element and the abutment is advantageous for securing the dental implant arrangement.

[0064] The connecting element can be selected from the state of the art. The connecting element can be, for example, a screw, a bayonet lock, a bolt, or a locking pin. A screw is preferred for securing the abutment to the base body.

[0065] Preferably, the external connecting element is a screw. The screw is shaped to fit into the opening of the abutment and secure the abutment to the base body. Preferably, the head of the screw is conical or convex in shape so that it can be fitted into the opening and is in a force-fitting connection with the opening and / or any retaining elements present inside the opening. Further preferably, the screw has a thread to interact with a thread present inside the recess of the base body.

[0066] The external connecting element, preferably the screw, is made of metal, metal alloys, ceramic, or plastic. The external connecting element or screw is preferably made of polymers such as PE, PEK, PEKK, PEEK, or CFRP-PEEK; more preferably, these polymers are fiber-reinforced. In a preferred embodiment, the base body and the abutment are made of ceramic, and the external connecting element, preferably the screw, is made of plastic, preferably from the polymers listed above.

[0067] Preferably, the maximum extension of the screw along the longitudinal axis of the base body is at least 1.5 times, preferably at least 2 times as long as the maximum diameter of the screw.

[0068] In one embodiment, the fixation of the screw can be further improved by using an adhesive applied to the screw, the abutment, and / or the base body. The adhesive is preferably a dental fixation agent, a dental adhesive, or dental cement.

[0069] In a preferred embodiment, the abutment is anchored only with the external connecting element, i.e. purely mechanically without the use of adhesives such as glues or cement.

[0070] According to a further aspect of the present invention, there is provided a dental kit comprising: A dental implant arrangement as described above and a denture, an artificial crown.

[0071] The dental kit is intended for the complete replacement of a tooth. When mounted, the denture is in contact with the abutment. The denture may also be in contact with the main body, especially if it is a tissue-level implant. The denture covers at least parts of the tooth-implant assembly. Preferably, the denture covers the part of the dental implant assembly that protrudes above the gum line. Depending on the type of implant, "tissue-level" or "bone-level," either only the abutment (tissue-level) or both the abutment and main body (bone-level) are covered.

[0072] The dental implant arrangement according to the invention can be manufactured using manufacturing methods known in the prior art (e.g., with a conventional CNC milling machine or by means of CIM or other impression methods). Since the connecting element has a reduced cross-section compared to dental implants known from the prior art, dental implant arrangements with a base body diameter of less than 3.5 mm can be realized, while still ensuring stability and resistance to the effects of force. Thus, the dental implant arrangement according to the invention can also be used to replace incisors.

[0073] The present invention proposes an optimized matching interface geometry that enables the most ceramic-friendly load transfer possible by the pressure of the two parts on each other is spaced from the edges of the inner and outer transition areas because the contact line is located in the coupling area, point loads are minimized due to the concave and convex coupling areas and the load transfer along a contact line is ensured, thus enabling a ceramic-on-ceramic implant and the edges of the transition areas are rounded, thus avoiding cuts, increasing stability and reducing wear.

[0074] Furthermore, the dental implant arrangement according to the invention integrates the rotation lock into the contact zone (coupling section) of the base body and abutment, whereby more stable connecting elements with a larger diameter, such as screws, can be realized and the stability of the dental implant arrangement is thereby increased.

[0075] The present invention is further advantageous because the matching coupling areas of the interface lead to self-centering of the abutment on the base body when it is attached with the connecting element, the coupling areas with a recess-elevation gradient lead to a self-locking mechanism of the abutment on the base body, the geometric shape of the coupling areas with two different elevations and depressions enables an aesthetically pleasing presentation and the rounded transition areas of the base body and the abutment protect the gingival tissue, thereby avoiding inflammation and irritation in the patient.

[0076] In summary, the present invention describes a dental implant arrangement 1 for insertion into the jawbone of a patient. The dental implant arrangement 1 according to the invention serves to accommodate a dental prosthesis and comprises a base body 3, which connects the dental implant to the alveolar bone (i.e., the jawbone), an abutment 2, and a connecting element 51. The base body 3 and the abutment 2 each have a coupling region 14, 24. Together, these coupling regions 14, 24 form an interface. The coupling regions 14, 24 are concave and convex, respectively, and congruent in some regions. The abutment 2 and the base body 3 are connected by means of a connecting element 51. List of reference symbols

[0077] 1 Implant arrangement 2 Abutment 3 Basic body 5 Diameter of 41 6 Deepening of 41 7 Increase of 41 9 level 10 interface 11 Distance 14 coupling area 15 gap 16 internal thread 23 opening 24 coupling area 26 projection 27 Apical end of 2 28 Section 29 Coronal end 32 Apical end of 3 33 Shaft section 35 Coupling section 36 Coronal end 37 recess 38 Holding devices 41 Contact line 51 connecting element 241 Inner transition area 242 Outer transition area 313 Diameter of 3 341 Inner transition area 342 Outer transition area II' Longitudinal axis II-II' axis r3 Radius of 14 r2 Radius of 24

[0078] The invention is explained in more detail below with reference to the figures. All figures contain partial, schematic representations of the invention and are used as examples to explain the invention. Specific embodiments of the invention may differ from these figures. The representation of the dental implant arrangement according to the invention in the figures is sketchy and schematic.

[0079] This shows Figure 1 shows a section through a dental implant arrangement according to the invention, Figure 2 shows a perspective view of the dental implant arrangement according to Figure 1 , Figure 3 a cross section along the line II' of the dental implant arrangement according to Figure 2 , Figure 4 shows a section of the contact area between the base body and the abutment, Figure 5 shows a perspective view of a dental implant arrangement with an asymmetric shape in the area of ​​the interface, Figure 6 shows a perspective view of the base body of a dental implant arrangement according to the invention, with an elevation and a depression in the area of ​​the interface, Figure 7 shows a cross section of the base body according to Figure 6 , Figure 8 a perspective view of the base body of a dental implant arrangement according to the invention, with two elevations and two depressions in the area of ​​the interface, Figure 9 a cross section of the base body according to Figure 8 , Figure 10 a perspective view of the base body of a dental implant arrangement according to the invention, with three elevations and three depressions in the area of ​​the interface, Figure 11 a cross section of the base body according to Figure 10, and Figure 12 a photograph of the interface between the base body and the abutment.

[0080] Figure 1 shows a section through an implant arrangement 1 according to the invention. This comprises a base body 3, an abutment 2 and a connecting element 51.

[0081] In the assembled state, the abutment 2 is positively connected to the base body 3 by means of an interface 10. According to the invention, this interface 10 has features that enable precise positioning of the abutment 2 relative to the base body 3.

[0082] The features of the implant assembly 1 are described in detail in the following figures. In particular, the features of the interface 10 apply: the features described below for the base body 3 and the abutment 2 can also be arranged on the other part. In other words, in a specific embodiment, the features of the interface 10 described below that relate to the base body 3 can be arranged on the abutment 2. In this case, it is necessary that the features of the abutment 2 described below be arranged on the base body 3. This ensures precise positioning.

[0083] Figure 2shows an implant arrangement 1 according to the invention with a base body 3 and an abutment 2. The base body 3 has a shaft section 33 at its apical end 32. The shaft section 33 tapers along the longitudinal axis II' in the direction of the apical end 32 and is in the embodiment according to Figure 1 Conical in shape. A coupling section 35 is arranged at the coronal end 36 of the base body 3. The coupling section 35 is integrally connected to the shaft section 33 of the base body 3 and is part of the interface 10. The interface 10 arranged at the coronal end 36 enables a positive positioning of the base body 3 with the abutment 2.

[0084] As from Figure 3As can be seen, the base body 3 has a recess 37 at the coronal end 36. A connecting element 51 (not shown) is arranged in the recess 37, with which the base body 3 and the abutment 2 can be detachably connected. According to the embodiment according to Figures 2 and 3 The coupling section 35 is symmetrically formed and has a coupling region 14 at its coronal end 36, at the interface 10. This coupling region 14 extends from the cylindrical outermost edge of the coupling section 35 to the recess 37 and has a symmetrical shape. The outer transition region 342 from the coupling section 35 and the inner transition region 341 from the recess 37 into the coupling region 14 are preferably rounded. The coupling region 14 of the base body 3 is formed by a convex shape and has a radius r3. The coupling region 14 is part of the interface 10.

[0085] The abutment 2 is designed in the form of a sleeve. It has a through-opening 23 in the form of a bore. At the apical end 27 of the abutment 2, a coupling region 24 is arranged, which is part of the interface 10. This coupling region 24 extends from the cylindrical outermost edge of the abutment 2 to the through-opening 23 and has a symmetrical shape. The outer transition region 242 of the abutment 2 and the inner transition region 241 from the through-opening 23 into the coupling region 24 are preferably rounded. The coupling region 24 has a concave shape and has a radius r2 ( Figure 4 ).

[0086] According to the invention, the radii r2 and r3 differ in their values. The radius of the concave coupling region 24 is larger than the radius of the convex coupling region 14. This creates a circular contact line 41 after the abutment 2 and the base body 3 are joined together. This contact line 41 is arranged in the area of ​​the interface 10 and is formed by a plurality of points arranged in a row. The contact line 41 has a diameter 5, which is smaller than the diameter 313 of the coupling section 35 ( Figure 3 ). The center of each of the diameters 5, 313 lies on the axis I-I'. The linear contact 41 has, according to the embodiment according to the Figures 2 and 3 in relation to an imaginary plane 9 ( Figure 6) which is arranged perpendicular to the longitudinal axis II', has a constant distance from this plane 9. In other words, the contact line 41 is arranged perpendicular to the longitudinal axis II'. All points on the contact line 41 have the same distance from the fictitious plane 9.

[0087] Contact line 41 is Figure 4 The contact line 41 enables exact positioning of the base body 3 with the abutment 2. Due to the different values ​​of the radii r2 and r3, a gap is created in the area of ​​the transitions 341 and 241 as well as 342 and 242. As can be seen from Figure 4 As can be seen, the transition areas 341 and 342 can be designed with sharp edges. This also applies to the transition areas 241 and 242. The transitions 341, 241, 342, 242 are preferably rounded.

[0088] As from Figure 4As can be seen, the gap increases continuously from the contact line towards the transition areas. In the embodiment according to Figure 4 the value (distance) of the gap 15, which is determined parallel to the longitudinal axis, at the transition of the concave coupling region 14 to the transition region 241, 242 is a maximum of 0.05 mm, preferably 0.03 mm, particularly preferably 0.01 mm.

[0089] Figure 3 shows a section through the base body 3 and the abutment 2. The shape of the opening 23 is visible. To join the base body 3 with the abutment 2, a connecting element 51 ( Figure 1), for example a screw, is inserted into the opening 23. The connecting element 51 extends through the abutment 2 into the base body 3 and is fastened in the base body 3 by holding means 38. For this purpose, the base body 3 has holding means 38, for example in the form of an internal thread 16. In order to ensure a secure connection between the abutment 3 and the base body 3, the abutment 2 comprises at least one projection 26 which projects into the opening 23. In the embodiment according to Figure 3The projection 26 extends around the entire circumference of the opening 23. It is circular and inclined towards the apical end 27 of the abutment 2. The projection 26, which is designed as a phase, merges into a cylindrical section 28. This cylindrical section 28 forms a guide area for the connecting element 51 and has a smaller diameter than the opening 23 at the coronal end 29 of the abutment 2. The projection 26 is operatively connected to a correspondingly designed area of ​​the connecting element 51, thereby ensuring a secure connection between the base body 3 and the abutment 2.

[0090] Figure 5shows an implant arrangement 1 without the connecting element 51. The interface 10, which comprises the coupling section 35 of the coupling region 14 of the base body 3, is designed asymmetrically. This results in the contact line 41 of the coupling region 14 being inclined to plane 9, wherein plane 9 is oriented perpendicular to the longitudinal axis II' ( Figure 7). Individual points of the contact line 41 have different distances to the fictitious plane 9. The distance changes are constant. Assuming that the plane 9 is located at the coronal end 29 of the coupling section 35, the contact line 41 has an elevation 7 that intersects the plane 9. Starting from this elevation, the highest point 7 of the contact line 41, the latter slopes continuously to a depression 6 at the lowest point of the contact line 41. At this point 6, the distance 11 to the plane 9 is greatest. Starting from the lowest point 6, the contact line 41 rises continuously to the highest point 7. The contact line 41 according to Figures 5 , 6 and 7 has an elevation at point 7 and a depression at point 6.

[0091] The contact line 41 of the interface 10 according to an embodiment according to the Figures 8 and 9have two elevations 7 (highest point) and two depressions 6 (lowest point). Otherwise, the above feature descriptions apply mutatis mutandis.

[0092] The Figures 10 and 11 show the base body 3 of a dental implant arrangement 1 according to the invention, whose contact line 41 has three elevations 7 and three depressions 6. Otherwise, the above feature descriptions apply mutatis mutandis.

[0093] The contact line 41 of an interface 10 of a dental implant arrangement 1 according to the invention is formed by the interaction of the coronal end 29 of the coupling section 35 and the apical end 27 of the abutment 2. The above description of the shape of the contact line 41 using the example of the base body 3 applies accordingly to the contact line 41 of the abutment 2. The apical end 27 of the abutment 2 and the coronal end 29 of the base body 3 are congruent in some areas, with the values ​​of the diameters r2 and r3 differing. The diameter at the convex end is smaller than the diameter at the concave end. This is independent of which part (base body 3, abutment 2) the convex or concave part is arranged. The contact line 41 is created by joining the base body 3 and the abutment 2.

[0094] Figure 12shows a photo of an abutment 2 and a base body 3 in the assembled state. The abutment 2 has a maximum length (extension along the longitudinal axis I-I') of 6 mm and a maximum diameter of 3.9 mm. The lower part of the abutment 2 is cylindrical, the upper part conical, with the width decreasing along the longitudinal axis towards the upper part. The coupling section 35 of the base body 3 is cylindrical. The base body 3 is 20 mm long and has a nominal diameter of 4 mm. The abutment 2 is attached to the base body 3 with a screw (not shown) with an ISO M2 thread. The abutment 2 has the concave coupling area 24, the base body 3 has the convex coupling area 14. The concave and convex coupling areas are circular segments. The circle of the concave coupling area 24 has a radius of 1.1 mm, that of the convex coupling area 14 has a radius of 1.0 mm.The centers of the radii of the coupling regions 14, 24 lie within the base body 3 and are arranged at a distance of 0.5 mm from the circumference of the coupling section 35 of the base body 3. The coupling regions, in particular the region in which the contact line 41 is arranged, were machined in the green state. Additional processing in the form of smoothing or polishing in the fired state is not necessary. The transition regions 241, 242, 341, 342 are provided with a radius of 0.05 mm. The coupling regions of the dental implant arrangement have two elevations 7 and two depressions 6. The elevations 7, as well as the depressions 6, intersect planes that are arranged perpendicular to the longitudinal axis. The planes are arranged at a distance from one another. The distance between the maximum extents of the elevations 7 and depressions 6 is 0.6 mm.

[0095] As can be seen in the photo, the coupling areas 14, 24 have no sharp edges or steps. All areas are curved and rounded, preventing any localized stress on tissue and bone. Irritations in the form of inflammation, damage, etc., can thus be virtually eliminated in the ideal case. In this embodiment, the coupling area 14 of the base body 3 merges tangentially into the cylindrical surface of the coupling section of the base body 3.

Claims

1. A dental implant assembly (1) comprising a main body (3) which is at least partly incorporated into the jawbone, comprising a recess (37) which extends from the coronal end (36) of the main body (3) in the direction of the apical end (32) and a coupling region (14) at the coronal end (36), which encloses the recess (37) and is concavely or convexly curved, an abutment (2), wherein the abutment (2) has an apical coupling region (24) which is oriented towards the main body (3) and has a convex or concave geometry opposite to the coupling region (14) of the main body (3), wherein the coupling region (14) of the main body (3) forms an interface with the coupling region (24) of the abutment (2), and a connecting element (51) for fastening the abutment (2) on the main body (3), characterized in that the curvature of the concave coupling region is smaller than the curvature of the convex coupling region.

2. The dental implant assembly according to claim 1, wherein the main body (3) and / or the abutment (2) is made of titanium, titanium alloys, plastics or ceramic.

3. The dental implant assembly according to claim 1 or 2, wherein the main body (3) and / or the abutment (2) is made of ceramic, preferably of zirconium dioxide or zirconium dioxide alloys, such as yttrium oxide-stabilized zirconium dioxide (Y-TZP) or alumina-toughened zirconium dioxide (ATZ) or cerium oxide-stabilized zirconium dioxide.

4. The dental implant assembly according to claims 1 to 3, wherein the abutment (2) and the main body (3) are made of the same material.

5. The dental implant assembly according to any of the preceding claims, wherein the interface (10) has a convex coupling region (14) of the main body (3) and a concave coupling region (24) of the abutment (2).

6. The dental implant assembly according to any of the preceding claims, wherein the coupling regions (14, 24) of concave and convex shape form a contact line (41), preferably a circular or at least almost circular contact line (41) in the top view.

7. The dental implant assembly according to claim 6, wherein the diameter of the contact line (41) in the top view amounts to 40-99% of the diameter of the coupling portion (35) of the main body (3).

8. The dental implant assembly according to any of the preceding claims, wherein the coupling regions (14, 24) of the abutment (2) and of the main body (3) have at least one elevation (7) and at least one depression (6), preferably an even number of elevations (7) and depressions (6).

9. The dental implant assembly according to claim 8, wherein the coupling region of the main body (3) have a first elevation (7), a second elevation (7) and a first depression (6) between the first elevation (7) and the second elevation (7) as well as a second depression (6) between the second elevation (7) and the first elevation (7), and preferably the elevations (7) and depressions (6) are diametrically opposed to each other.

10. The dental implant assembly according to claim 9, wherein the most apically located point of the first depression (6) of the coupling region (14) of the main body (3) is located more coronally than the most apically located point of the second depression (6) and / or the most coronally located point of the first elevation (7) is located more apically than the most coronally located point of the second elevation (7).

11. The dental implant assembly according to any of the preceding claims, wherein the connecting element (51) is an external connecting element (51) which is incorporated into the recess (37) of the main body (3) through an opening (23) in the abutment (2), which extends from the coronal end (29) to the apical end (27) of the abutment (2).

12. The dental implant assembly according to claim 11, wherein the connecting element (51) is a screw.

13. The dental implant assembly according to claim 11 or 12, wherein the external connecting element (51) is made of a plastic material, preferably of PE, PEK, PEKK, PEEK or CFK-PEEK, particularly preferably of fiber-reinforced PE, PEK, PEKK, PEEK or CFK-PEEK.

14. A dental kit comprising at least one dental implant assembly according to any of the preceding claims and at least one dental prosthesis.