Removable dental prosthesis, telescopic crown, male element for use with such a dental prosthesis or in such a telescopic crown, crown body, and method for producing a dental prosthesis system

Abstract

A removable dental prosthesis (1), comprising a prosthesis body (2) and a number of female elements (18, 168) which can each be plugged onto an associated male element (14, 14', 14'') arranged in particular on a tooth (6) or an inserted dental implant (72) in the oral cavity of a patient, and a female element (18, 168) suitable for use in such a dental prosthesis (1) are to be able to be produced with a particularly high accuracy of fit while maintaining a particularly low level of complexity. For this purpose, according to the invention, the or each female element (18, 168) has an inner cap (32, 160) which forms a contact surface (31) for the associated male element (14, 14', 14'') and can be plugged onto the latter, the inner cap being made of a comparatively hard plastic in the region of the contact surface (31) and being fastened to the prosthesis body (2) via an intermediate body (36) formed from what is by comparison a softer plastic.

Description

[0001] Description

[0002] Removable dental prosthesis, telescopic crown, male element for use with such a dental prosthesis or in such a telescopic crown, crown body and method for producing a dental prosthetic system

[0003] The invention relates to a removable dental prosthesis comprising a prosthesis body and a number of matrix elements, each of which can be attached to an associated male element. It further relates to a telescopic crown for attaching a removable dental prosthesis to a tooth or an inserted dental implant in the oral cavity of a patient, comprising a male element attachable to the tooth or dental implant and a matrix element attachable to the male element and attachable to the dental prosthesis. It further relates to a male element for attachment to a tooth or implant in the oral cavity of a patient, in particular for use with such a dental prosthesis, a crown body, and a method for producing a dental prosthetic system comprising such a dental prosthesis.

[0004] When teeth are lost, the usual goal is to replace them or at least close the gaps created by the loss. This can be achieved, for example, with so-called bridges. In this case, the teeth adjacent to the gap are ground down, and a crown is fabricated, which replaces the missing teeth with appropriate bridge elements. The bridges are mechanically anchored to the ground down teeth. A pendant can also be attached to a bridge, which provides support for a free-end situation. This type of situation can also be treated with removable clasp dentures, which are usually supported by natural teeth.

[0005] In addition to bridgework, lost teeth can also be replaced with endosseous implants. These typically use threaded pins as artificial tooth roots, to which the prosthetics can be anchored.

[0006] This anchorage can also be fixed (screwed, cemented, or bonded) or removable. With removable anchorages, the adhesive forces that hold the prosthesis in position are usually based on a vacuum effect, friction, and / or retention.

[0007] When too few teeth remain in the patient's mouth, other solutions are usually used. One option is to remove all remaining teeth and use mucosal-supported dentures. These are inexpensive, but offer poor chewing comfort for the patient and are usually accompanied by bone loss in the upper and lower jaw.

[0008] The remaining teeth and / or endosseous implants are often used as abutments for removable restorations. A wide variety of solutions are available. Clasp dentures, double crown techniques on teeth and / or implants, electroplating techniques on teeth, implants, and / or implant bars, conical clasp systems, ball head anchors, silicone-metal matrix-patrice systems, and other systems can be used.

[0009] In particular, so-called telescopic systems can be used, in which a dental prosthesis or dental replacement is removably attached to so-called telescopic crowns. These telescopic crowns are double crowns in which a "lower" or base crown, also referred to as the "primary crown", in particular a male element, is firmly attached in the manner of a conventional crown to a suitably prepared, e.g., ground, tooth or even an inserted dental implant (one-piece or two-piece). On its upper side, this male element forms a contact pin to which an "upper" crown segment or female element, also referred to as the "secondary crown", can be attached, for example, clicked or clipped on, in a detachable or removable manner. The crown segments thus form a type of female-male system.The upper crown segment, forming the matrix, then serves as a support for the prosthesis. The detachable connection of the crown segments allows the entire denture to be removed. Commonly used are parallel or conical telescopes, which can be cast, milled, or gold-plated.

[0010] The first step in the production of all these systems is usually to record the patient's oral situation, for example by taking an impression using suitable impression material. The oral situation is then usually transferred to a physical model, such as plaster, plastic, or a virtual model. Using this model, the dental technician can then fabricate the prosthetics according to the situation and requirements, so that they can later be inserted into the patient's mouth with the greatest possible fit. The accuracy of fit is a very important factor, as a high level of fit is a prerequisite for the prosthesis to sit securely in the patient's mouth. Furthermore, a high level of fit also naturally requires a high level of comfort for the patient, so that they can feel as comfortable as possible with the prosthesis.The more precisely the prosthesis is manufactured, the more firmly it can fit in the patient's mouth, which in turn leads to a very high level of wearing and chewing comfort. Conversely, the more flexible the removable fixation is, the more loosely it fits in the patient's mouth. While this simplifies the manufacture of the prosthesis and reduces production costs, a particularly high level of fit is usually sought after, taking these aspects into account.

[0011] A problem that has emerged in this context is that the described transfer of the patient situation to a physical or virtual model can significantly contribute to undesirable inaccuracies in the fit.

[0012] In order to provide a highly precise matrix-patrice system, the matrices anchored in the denture can be cemented or bonded in the patient's mouth to avoid inaccuracies. However, this involves increased effort and correspondingly higher costs.

[0013] Furthermore, all these systems are subject to wear and tear due to repeated removal and insertion in the patient's mouth, which also varies depending on the system. This wear and tear should be kept to a minimum when designing new concepts.

[0014] Another function of removable restorations is that the adhesive strength should be reproducible and give the patient the feeling of having fixed teeth, while at the same time not jamming the denture when removed. This means that the adhesive strength should not be too high and, if possible, should be independent of the patient's previous purchasing power.

[0015] Currently, among the telescopic systems of the type described, matrix-patrice systems based on a gold-plated matrix on a ceramic matrix represent the most popular and, in terms of their properties, the best variant in terms of wearing comfort and balance in the areas of adhesion or adhesive force and wear. Within the matrix-patrice system, they achieve the highest degree of fit accuracy and thus also have optimal suction or negative pressure effect with regard to adhesive forces. Due to the high-precision fit, they also have very low wear. Since the system is usually conical in the area of ​​the matrix-patrice connection and rests occlusally, there is no conical self-locking in the system, which means that the adhesive forces remain virtually independent of the chewing force and no jamming occurs during removal. The main disadvantages of these systems are the very complex manufacturing process and the very high price.

[0016] The high cost is justified as follows: The dentist takes an impression of the patient's actual oral situation. The dental technician creates a patient model. The patrices are manufactured, acquired, or purchased, either prefabricated on implants or using the CAD / CAM process, or cast on natural teeth using the CAD / CAM process (or previously cast). The matrices are then manufactured or purchased partially prefabricated on implants. A metal framework is then fabricated. The entire assembly is then sent to the dentist. The dentist fixes (screws, glues, or cements) the patrice elements onto the teeth or implants. They then glue or cement the matrix elements into the framework. This carries the risk of the matrix-patrice system becoming stuck in the patient's mouth, which can necessitate time-consuming removal.The entire assembly is then sent back to the dental technician, who can create the finished prosthesis on the framework. Only then is the prosthesis complete and can it be finally inserted into the patient's mouth. The advantage, however, is that the fit inaccuracies of the usually four-matrix-patrix systems can be minimized to a great extent by transferring the prosthesis from the patient to the model.

[0017] Currently, attempts are being made to replace the gold electroplating matrix with a plastic matrix, usually milled or 3D-printed. PTFE, PEEK, PPS, and plastics with similar properties are commonly used.

[0018] The unpublished German patent application No. 102022 127 865.4, entitled "Telescopic Crown," describes a telescopic crown that is significantly improved compared to the prior art, which avoids the aforementioned disadvantages and allows the provision of a dental prosthesis with a particularly high degree of precision at a relatively low cost. In this improved telescopic crown, the matrix element is constructed in several parts and comprises an inner cap that can be attached to the patrix element and an outer cap that can be attached to the dental prosthesis. An intermediate body made of thermoplastic elastomer material is arranged in the space between the inner and outer caps, connecting them together.

[0019] The invention is therefore based on the object of providing an even further improved removable dental prosthesis of the above-mentioned type or an even further improved telescopic crown of the above-mentioned type, with which the described disadvantages can be avoided and which can be manufactured with a particularly high degree of accuracy and with particularly low expenditure. Furthermore, a male body particularly suitable for use as a male element with such a dental prosthesis, intended for attachment to a tooth or implant in a patient's mouth, and a method for producing a dental prosthetic system with such a dental prosthesis are to be provided.

[0020] With regard to the removable dental prosthesis of the aforementioned type, this object is achieved according to the invention in that the or each matrix element has an inner cap that forms a contact surface for the associated male element and can be attached thereto. The inner cap is made of a comparatively hard plastic in the region of the contact surface and is attached to the prosthesis body via an intermediate body made of a comparatively softer plastic. According to one aspect of the invention, "comparatively soft" can also be understood to mean a material that has a lower softening temperature than the material of the inner cap.

[0021] In one embodiment, the assembly comprising the inner cap and intermediate body can be arranged directly on the prosthesis body. In a further embodiment, which is considered to be independently inventive, this assembly can also be attached to the prosthesis body indirectly, namely via a further matrix cap. Accordingly, the stated object with regard to the telescopic crown of the type mentioned above is achieved according to one aspect of the invention in that the matrix element is designed in several parts and comprises an inner cap which forms a contact surface for the associated patrix element and can be plugged onto it, and an outer cap which can be attached to the dental prosthesis. The inner cap is made of a comparatively hard plastic in the region of the contact surface, and an intermediate body made of a comparatively softer plastic is arranged in the space between the inner and outer caps, connecting them to one another.

[0022] Such a system, considered to be independently inventive, consists of an inner cap (made of comparatively hard plastic), an intermediate body (made of comparatively softer plastic), and the matrix cap (preferably made of plastic, metal, or ceramic) intended for the final connection to the prosthesis body. In terms of functionality, such a telescopic crown, even with the special configurations described above or below, is considered to be independently inventive.

[0023] The invention is based on the idea that a high degree of precision fit of the prosthetic in the patient's oral cavity can be achieved by only relatively roughly adapting the components used to create the prosthetic to the patient's oral situation during the preparation phase. The final adjustment and fine-tuning should only take place during insertion into the patient's oral cavity and in response to the resulting restoring forces, etc. To achieve this, one of the components, i.e., the female or male part, should be designed in such a way that the final positioning and alignment of the removable denture only takes place during insertion into the oral cavity.For this purpose, the male part, or preferably the female part, is to be attached to its respective support—in particular, the female part to the actual prosthetic body of the denture—in such a flexible manner that the final alignment of the female part relative to the male part, and thus the final positioning during insertion, occurs in response to the forces occurring in the oral cavity. For this purpose, the actual contact body of the female part, which is brought into mechanical contact with the associated male part, i.e., the inner cap, should be attached to the prosthetic body of the denture via a correspondingly flexible and suitably deformable intermediate body.

[0024] To further account for the fact that, especially in the case of removable dentures, the connection area could be subject to particularly intensive wear due to the repeated loosening and re-establishment of the connection, the actual contact body of the matrix element should also be made of a material that is both comparatively wear-resistant and also capable of being produced with a particularly smooth surface. To this end, according to one aspect of the invention, the matrix element, in the region of its inner cap forming a contact surface for the associated male element, is made of a comparatively hard plastic that can be repeatedly attached to and removed from the associated male element with a long service life and low wear.

[0025] In order to enable all of these aspects to be combined with one another and thus to provide a long-lasting, particularly precisely fitting and highly comfortable dental prosthesis, according to a basic concept of the invention, the material pairing of a plastic-based, comparatively hard inner cap forming the contact surface to the male element is provided in the connection area of ​​the matrix element with the male element, with the intermediate body forming the connection to the prosthesis body or the outer cap of the matrix element and made of softer plastic in comparison.

[0026] According to aspects of the invention, ethylene-vinyl acetate copolymer, polyethylene, polypropylene, polyolefin, or polyamide are considered particularly favorable base materials for the intermediate body. In order to satisfy the aforementioned "soft plastic" criterion, the intermediate body should preferably have a certain deformability following the basic concept described above. According to aspects of the invention, the tensile modulus of elasticity is considered a suitable criterion for this; advantageously, the intermediate body has a tensile modulus of elasticity of less than 100 MPa. In further advantageous embodiments, the intermediate body can alternatively or additionally have a tensile modulus of elasticity of approximately 65 MPa, an elongation at break of more than 50%, a yield stress of 5-10 MPa, and / or a tensile strength of 10-20 MPa.

[0027] Furthermore, the plastic forming the inner cap should have comparatively high abrasion resistance and mechanical strength so that repeated removal and reinsertion of the dental prosthesis is possible without significant wear of these components. According to further aspects of the invention, PEEK, PPS, PPSU or PSU are considered to be particularly suitable base materials for the inner cap forming the contact surface to the male element. In order to satisfy the aforementioned “hard plastic” criterion, the contact surface should preferably have a certain rigidity in line with the basic concept described above. According to aspects of the invention, the tensile modulus of elasticity is also considered to be a suitable criterion for this; advantageously, the part of the inner cap of the female element forming the contact surface has a tensile modulus of elasticity of at least 1000 MPa, preferably of at least 2000 MPa.In further advantageous embodiments, the intermediate body can alternatively or additionally have a tensile modulus of elasticity of more than 2500 MPa, preferably approximately 4200 MPa, an elongation at break of less than 25%, a flexural strength of 150-200 MPa, and / or a tensile strength of 100-200 MPa. The base material polyetheretherketone (PEEK), which is considered particularly suitable, for example, has a tensile strength of 110 MPa, a flexural strength of 170 MPa, an elongation at break of 11%, and a tensile modulus of elasticity of 4210 MPa.

[0028] As described above, one of the significant aspects of the invention is considered to be the material and functional pairing of the "relatively hard" contact surface of the matrix element, on the one hand, with the "relatively soft" intermediate body, on the other. This can be achieved quantitatively, for example, by selecting, according to one aspect of the invention, the ratio of the tensile moduli of elasticity of the intermediate body to the inner cap to be less than 1:10, preferably less than 1:25, and most preferably less than 1:50.

[0029] According to another concept considered to be independently inventive, the inner cap can also be connected to the prosthesis body via an intermediate body that progressively solidifies during or immediately after initial insertion or integration, starting from an initially deformable state. The solidification should occur during integration so that influences from the oral environment can be incorporated and the components can automatically align themselves in an optimized manner in response to the oral situation. Subsequently, i.e., after solidification, the optimized alignment of the components thus acquired should be suitably fixed.

[0030] For this purpose, for example, the intermediate body could be designed to form a cement or adhesive bond which, with a sufficiently dimensioned volume for the cement or adhesive, offers sufficient scope for optimizing the positioning and alignment of the components as long as the cement or adhesive is in the solidification phase. According to one aspect of the invention, however, the intermediate body is made of a thermoplastic material, preferably a thermoplastic elastomer material. During insertion, the intermediate body can be suitably heated beforehand so that a certain softening and thus deformability occurs. Insertion can then be carried out in this state so that the inner cap can be suitably aligned in relation to the prosthesis body or outer cap according to the fine details of the oral situation.Upon cooling, the intermediate body solidifies again while retaining this geometry, thus appropriately securing the desired optimized positioning. In a particularly preferred embodiment, the thermoplastic intermediate body is made of a thermoplastic elastomer. The advantage is that the retention function, as a snap-fit, can be more easily adjusted in terms of force. Furthermore, an elastomer layer will not fatigue as quickly and its adhesive force will not decrease. This also contributes to minimizing wear in the matrix-pattern system. In this sense, the criterion of a "lower softening temperature" for the intermediate body can also replace the criterion of a "softer plastic."

[0031] The inner cap of the matrix element should be able to be tilted or displaced relative to the outer cap during final alignment, i.e., during curing of the thermoplastic intermediate body. Advantageously, and according to one aspect of the invention, the inner cap is made of a plastic, preferably a high-performance plastic. According to one aspect of the invention, this plastic should have a softening temperature significantly above the softening temperature of the thermoplastic intermediate body, preferably 25%, 50%, or even 100% higher. The thermoplastic intermediate body provided according to one aspect of the invention can be designed in the form of a layer, i.e., preferably as a thermoplastic layer. The introduction of such a thermoplastic layer can compensate for the inaccuracy of fit between the patient situation and the model situation in the dental technician.

[0032] According to one aspect of the invention, the softening temperature of a material suitably selected in the general sense according to the concept of the invention, in particular of the thermoplastic layer or the thermoplastic intermediate body, is selected above 60°C, advantageously below 160°C, particularly preferably below 120°C, in particular through suitable material selection. This is based on the consideration, regarded as independently inventive, that the softening temperature should be selected as low as possible during insertion into the patient's mouth, but above the temperature that hot drinks have or that can occur when cleaning the prosthesis. Common and conventional autoclaves are used at temperatures above 135°C, which are also used, for example, to autoclave prostheses for preparation for use or for disinfection.According to one aspect of the invention, the material parameters of the intermediate body are selected such that, at the usual temperatures and treatment times in the autoclave, taking into account the thermal inertia during such autoclaving, thermoplastic softening does not occur. Thus, even during such autoclaving, the position of the inner cap facing the male part relative to the position of the outer cap facing the denture does not change, and the position previously established according to the concept of the invention is also not changed during autoclaving. The lowest acceptable softening temperature for the material of the intermediate body should therefore preferably be in the range of 60°C - 80°C.These are temperatures which a patient is unlikely to reach even when cleaning his dentures using the home faucet, so that deposition of the inner cap facing the patrix due to deformation of the intermediate body during daily use can be ruled out.

[0033] When heating the components and immediately inserting the prosthesis for the purpose of finely aligning the components, especially the inner cap in relation to the outer cap, there is always a risk of thermal damage to the patient's mucosa and / or dental tissue (nerve) and / or bone (via heat conduction from the abutment and implant). For this reason, the softening temperature is preferably chosen to be relatively low. In addition, the heat capacity of the thermoplastic material forming the intermediate body should be relatively low, which is certainly the case due to the low thickness of the three-layer system.

[0034] According to one aspect of the invention and in a particularly advantageous development, the intermediate body is still "softer" in the above-mentioned sense than the contact surface of the inner cap of the matrix element, even after solidification. In a further advantageous embodiment, the material of the intermediate body particularly preferably exhibits little or no plasticity at temperatures of up to 40°C.

[0035] The dental technician can complete the entire prosthesis on his model. The finished prosthesis may deviate from the actual patient situation due to manufacturing tolerances in the positions of the patrices relative to the matrices by a few pm, for example 50 pm up to, for example, 250 pm. The introduction of the thermoplastic layer provided according to one aspect of the invention or the comparatively soft intermediate body is able to compensate for this. In order to be able to achieve this compensation, the intermediate body should preferably have a corresponding thickness of at least 100 pm and at most 750 pm, preferably at least 150 pm and / or at most 500 pm, particularly preferably at least 250 pm and / or at most 400 pm. When inserting the intermediate body into the patient's mouth, it can be provided in particular that the intermediate body - if it is designed as a thermoplastic body - is thermally heated above its softening point orthe softening interval so that it is malleable. When the prosthesis is then inserted into the patient's mouth and the patient bites, the inner caps of the matrix elements, "floating" in the softened thermoplastic layer or the softened thermoplastic intermediate body, align themselves precisely with the patrices. After cooling, the thermoplastic layer becomes solid again, and the aligned positions of the matrices are retained. This process can be repeated several times as needed, even after extended wear.

[0036] According to an aspect considered to be independently inventive, metallic particles can be embedded in the thermoplastic intermediate body. The intended heating, up to the point of softening the thermoplastic layer, can then be achieved by induction and thus, if necessary, without contact.

[0037] According to a further aspect considered to be independently inventive, magnetic particles, such as iron or iron oxide, can be embedded in the thermoplastic intermediate body. The intended heating can then be carried out, in particular by generating friction, with an alternating magnetic field and thus also without contact.

[0038] In a further aspect, considered to be independently inventive, the intermediate body can also be designed for contactless heating. According to one aspect of the invention, the intermediate body can be operated like a dielectric of a capacitor. For this purpose, the die cap or a metallic capsule enclosing the die in the direction of the die cap should form a capacitor surface. The capacitor surface to be positioned opposite can be formed by a metallic counterpart that is identical or very similar in shape to the male part. This is inserted into the die for the heating process. A voltage in the high-frequency range is then applied between the die cap and the counterpart, which preferably only excites the intermediate body, so that the losses are only formed in this and thus heat it.With regard to the male element for use with a dental prosthesis or in a telescopic crown of the type described above, the stated object is achieved according to the invention in that the male element has a contact surface corresponding to the contact surface of the respective female element, which contact surface is provided with a groove or undercut. This allows the retention required for reliable fixation of the removable dental prosthesis in the patient's mouth to be provided in a particularly simple manner.

[0039] According to aspects of the invention, the male element can be intended for attachment to a tooth in the patient's mouth and accordingly configured as a suitably shaped male body, or it can be part of a dental implant system. In the latter case, the male element according to one aspect of the invention can be molded onto an abutment of a dental implant and thus configured as an integral part of the abutment, or it can be configured as a separate component for mounting on such an abutment.

[0040] In a particularly preferred embodiment, the contact surface of the male element has a cross-section that tapers toward the free, occlusal end, preferably in the form of a conical shape. The male element thus tapers toward its free end, so that when attaching the corresponding female element and the components attached to it (e.g., the prosthesis or the upper part of the telescopic crown), pivoting movements relative to the longitudinal axis of the male element are also possible to a certain extent due to the provision of the aforementioned intermediate body. This can significantly improve the fine alignment of the components during the final adaptation to the oral situation.

[0041] With regard to the shape and cross-section of the male-male system, several alternatives are conceivable according to aspects of the invention. The simplest cross-sectional shape for the male-male system can be a round design. This design is particularly easy to implement for systems on implants. However, depending on the required force transmission area, an oval design (elliptical, trioval, quadoval) may also be preferred. With a round cross-section, the space requirement increases with increasing cross-sectional diameter, particularly when restoring natural teeth. The prosthesis fixed to the matrix-male system is also spatially limited in its ability to integrate the matrix, particularly in the buccal-palatal or buccal-lingual plane.In contrast, there is more space available in the mesio-distal extension, as this is the orientation of the dental arch. In order to utilize this available space particularly effectively, oval designs may be useful according to one aspect of the invention, as these would allow for a larger force transmission surface, friction surface, and retention surface. The radii of the cross-sections should preferably remain as oval as possible and should contain neither corners, straight lines, nor concavely curved areas. Furthermore, radii smaller than 1.0 mm and especially smaller than 0.5 mm are unsuitable, as retention in these areas is likely to result in greater wear.

[0042] In the case of natural teeth, it may even be necessary to deviate from the round shape, since the remaining dentition of the different patients may not be known before the actual treatment. The cross-section of natural teeth is usually oval, not round. This means that a ground tooth does not have a round cross-section, and consequently a round patrice design is rarely suitable. Instead, according to one aspect of the invention, oval / elliptical cross-sections can be advantageous and suitable in the anterior tooth region, trioval for the canines, and more quadoval in the posterior tooth region. These can of course also have partially straight or concave areas. According to one aspect of the invention, the patrice body is therefore designed with a non-round, elongated cross-section when viewed from above.

[0043] According to one aspect of the invention, retention provided by the geometry is primarily intended in a mesio-distal orientation so that the caps on the stumps / abutments can be designed with comparatively thin walls in the buccal-palatal or buccal-lingual plane. The space required for the retention elements in the patrix preferably consists of a notched groove, which is then preferably only provided in the front and rear areas where sufficient space is available. In this embodiment, according to one aspect of the invention, the groove or undercut, viewed in plan view, is thus limited to a partial segment of the contact surface intended for orientation in the mesio-distal direction in the patient's mouth. This concept can of course also be implemented for the patrixes of the abutments on the dental implants.On the other hand, especially when using dental implants, a substantially round basic shape may be advantageous due to the design options then available in the selection of the geometry; for reasons of reduced manufacturing effort, the abutment forming the male element can thus, according to one aspect of the invention, also be provided with a completely circumferential groove. A dental implant with an abutment that has a circumferential groove in the region of its contact surface is considered to be independently inventive, as is such an abutment that has a circumferential groove in the region of its contact surface. The two-part dental implant described here, consisting of a post part that osseointegrates into the bone and an associated superstructure part, can of course also be designed in one piece in one embodiment of the invention.

[0044] Advantageously, the male element is made of titanium or a dental ceramic.

[0045] According to one aspect of the invention, the male part is provided in its occlusal end region with one or a number of marking elements for an oral scanner. In this way, after its integration into the patient's mouth, the respective male part can be used as a functional extension, in addition to its actual support function for the denture, as a reference or marking point for creating oral scans. In particular, the design of the marking elements can be such that three-dimensional data can also be obtained, such as, for example, the inclination of the upper or occlusal end surface of the male part, if at least three marking elements are present.

[0046] With regard to the dental prosthetic system, the stated object is achieved according to one aspect of the invention by a combination of the removable dental prosthesis of the type described above with a number of male elements of the type described above, each intended for attachment to a tooth or implant in the mouth of a patient.

[0047] In a preferred embodiment considered to be independently inventive, at least one of the matrix elements of the denture is provided with a locking element that can be inserted into the groove or undercut of the associated male body. This locking element, which according to one aspect of the invention is preferably designed to be resilient, can create a locking connection system between the denture and the male element(s) in the patient's mouth, which particularly facilitates and facilitates the desired removal and reinsertion of the denture.

[0048] According to one aspect of the invention, this configuration is particularly favored by the basic design of the die elements with the comparatively soft intermediate body, which naturally provides a certain degree of deformability and is thus particularly suitable for such a connection. In particular, the intermediate body can have a spring effect and provide a certain restoring force, so that an associated locking element can snap into the respective groove. In a further advantageous embodiment and according to an aspect considered to be independently inventive, the or each locking element can be formed by a molding of the inner cap of the respective die element.

[0049] A system in which the anchoring takes place on an implant and, accordingly, the abutment of the implant forms the male element and forms a circumferential groove on its contact surface is considered to be independently inventive. According to one aspect of the invention, the available space for providing the locking element, preferably in the mesio-distal direction, can be taken into account by providing the abutment forming the male element with a completely circumferential groove, but the corresponding locking elements in the area of ​​the female element, viewed from above, are arranged only in a partial segment of the contact surface intended for alignment in the mesio-distal direction in the patient's mouth.

[0050] A crown body designed according to the latter considerations is considered to be independently inventive. According to this aspect of the invention, a crown body intended for attachment to a tooth stump or a dental implant in a patient's mouth comprises a contact surface on which at least one retention element is arranged, wherein all of these retention elements are positioned on the contact surface within an angular range of at most 60°, relative to the mesio- and / or distal main direction. This is based on the consideration that for the preparation and attachment of dental prostheses, there is usually comparatively good space available in a direction "along the dentition," i.e., in a mesio and / or distal orientation, whereas comparatively little space is usually available in a direction "transverse to the dentition," i.e., in a buccal-palatal or buccal-lingual orientation.According to an aspect of the invention considered to be independently inventive, the elements intended for producing the retention are thus primarily or almost entirely limited in the mesio-distal direction. Accordingly, according to an aspect considered to be independently inventive, corresponding retention elements are arranged on the circumference, viewed in plan view, in an angular range relative to the mesio-distal direction of less than 75°, preferably less than 60°, particularly preferably less than 45°, and are limited to this.

[0051] Such a connection system offers enormous advantages because the only partial or partial provision of retention elements in the circumferential direction means that these can be limited to a sub-segment or sub-area in which there is sufficient space for the attachment of such elements, particularly with regard to the oral or dentition situation. The retention elements defined here as “essential retention elements” are to be understood in particular as those which, as a whole, contribute the significant proportion of the required retention forces, in particular more than 75%, preferably more than 90%, and particularly preferably more than 95% of the total applied or required retention forces. In particular, the retention elements referred to here should have an undercut depth of at least 100 pm.

[0052] The respective retention element could be designed as a bulge or an outwardly projecting element that interacts with an associated groove or notch in a corresponding female element. Advantageously, however, and according to one aspect of the invention, the respective retention element is designed as a notched groove, preferably positioned on the lateral surface of the crown body. The use of a crown body of the type defined above as a male element according to the construction described above is also considered to be independently inventive.

[0053] The prosthetic system provided according to aspects of the invention particularly and preferably has one or more of the following aspects: It is a matrix-pattern system

[0054] The male part is formed by a male part attached or molded to an abutment of a dental implant or to a prosthetic-bearing part of a one-piece implant, or by a male part fixed to a natural tooth.

[0055] The matrix is ​​formed by an inner cap with a contact surface, which is placed over the male body.

[0056] If the male part is designed as an abutment, it advantageously has a diameter of 1.5 mm to 6 mm at its largest point, preferably 2 mm - 4 mm and particularly preferably 2 mm - 3 mm

[0057] If the patrix is ​​designed as a crown on a natural tooth or as the part supporting the prosthetics, it advantageously has a non-round design with a width of 2 mm to 8 mm, preferably 2 mm - 6 mm and particularly preferably 3 mm - 5 mm and a length of 3 mm to 8 mm, preferably 2 mm - 6 mm and particularly preferably 3 mm - 5 mm

[0058] The male part advantageously has a height of 2mm to 8mm, preferably 2 - 6mm and particularly preferably 3mm - 4mm.

[0059] If the patrix is ​​designed as a cap on a natural tooth, the prepared tooth determines the cross-section and functional height. The preparation angle is advantageously 1° to 6°, particularly preferably 2° to 4°.

[0060] If the male part is designed as an abutment or as the prosthetic component, it is also possible to attach a cap to it. This cap is either occlusally closed or, in the case of an abutment, has an opening for access to the abutment screw.

[0061] The male caps are preferably cemented / glued (adhesively attached). However, they can also be screwed. Alternatively, the adhesion / fixation can also be achieved via a conical self-locking mechanism.

[0062] The male part, designed as a cap on a natural tooth, an abutment or as the part carrying the prosthesis, is preferably made of titanium or titanium alloy, zirconium or zirconium alloy, tantalum or tantalum alloy, a non-precious metal or a ceramic based on zirconium dioxide (ZrO2) and or aluminum oxide (AI2O3) and or a silicate ceramic or an alloy of the metals or a mixture of the ceramics

[0063] Adhesion / the adhesive force between the male and female parts is based to a small extent on a conical design (the angle bisector should be, according to one aspect of the invention, 2° - 10°, preferably 2° - 8°, particularly preferably 4° - 6°) via suction effect

[0064] Adhesion / adhesive force between the male and female parts is based on a conical design (the angle bisector should be, according to one aspect of the invention, 6° - 20°, preferably 8° - 15°, particularly preferably 10° - 12°) via suction effect and additional retention by means of at least one circular undercut

[0065] The undercut is cut into the cone of the body part as a circumferential bead and preferably as a circumferential groove

[0066] The undercut is located in the conical area of ​​the abutment. It is preferably positioned in the apical half, the apical third, or the apical quarter of the conical portion.

[0067] The adhesion / holding force can but does not have to be additionally supported by a conical self-locking mechanism.

[0068] The abutment is preferably made of titanium or titanium alloy, zirconium or zirconium alloy, tantalum or tantalum alloy, a non-precious metal or a ceramic based on zirconium dioxide (ZrCh) and / or aluminum oxide (AI2O3)

[0069] According to a further aspect of the invention, which is considered to be independently inventive, a ceramic material can be provided for the male part. Ceramic is particularly suitable as a male part material for aesthetic reasons. For example, the patient usually feels more comfortable with a removed denture if the supporting abutments are tooth-colored rather than metallic.

[0070] With regard to the method for producing a dental prosthetic system with a removable dental prosthesis of the type described above, which is intended for removable fixation to a number of crowned teeth or in particular also dental implants in the mouth of a patient by means of a number of patrice bodies each forming a patrice element, the stated object is achieved by recording intraoral data reflecting the actual dentition situation in the patient's oral cavity before or after the first preparation of the teeth and making it available for digitalized further processing, wherein on the basis of this data, preferably in a CAD system, a suitable patrice element is selected for each intended patrice element from a number of basic patrice element types stored in a component library.The acquisition of the intraoral data can take place in the manner of a first step, before the first preparation of the teeth takes place, or alternatively and according to a particularly preferred aspect, the teeth can also be prepared first by the practitioner. If the teeth are prepared in the first step, the practitioner can do this as if they were preparing the teeth for a crown and / or bridge. In particular, according to one aspect of the invention, it can also be provided that after the initial preparation, if no further treatment is required according to the following criteria and the use of a patrice body design stored in the component library is possible without further post-processing, this information is made available to the practitioner as a recommendation for action.

[0071] In the aforementioned aspects, the invention is based on the idea that a further improved and simplified manufacturing process should specifically utilize the possibilities and degrees of freedom provided by the aforementioned improved design of the matrix-patrix connection. In particular, this can take advantage of the fact that, due to the multi-part design of the matrix elements, the fine alignment and adjustment of the components relative to each other is only possible at a relatively late stage, i.e., upon insertion into the patient's mouth. Until then, relatively roughly prefabricated components can be used.This also allows, among other things, the use of standard components that can be easily produced in larger quantities and are then finely aligned and positioned in detail only in the final production step, taking advantage of the degrees of freedom enabled by the comparatively soft and, in particular, thermoplastic intermediate piece. Such standard components can thus be stored as basic types in a library and made available for selection.

[0072] According to aspects of the invention, the manufacturing process of the patrices on natural teeth, including software and library, is designed according to the following aspects and criteria:

[0073] Providing natural teeth intended as abutments for prosthetics with appropriate patrices or prefabricated patrice caps fundamentally represents a very significant challenge. The dentist must prepare the tooth stumps in order to be able to use them as abutments at all. This would require the teeth to first be prepared in such a way that a prefabricated patrice cap can be precisely fixed. The height, cone angle, and cross-section of the ground tooth, and therefore the tooth as a whole, would have to be adapted as precisely as possible to the inner lumen of the patrice cap. In addition, the intended insertion angle of the prosthesis must also be taken into account when attaching the prosthesis to the abutments. This is particularly important because two to eight (preferably four to six) abutments would have to be prepared in such a way that, after the patrice caps have been fixed, the prosthesis can be inserted without tension.

[0074] The object posed here is achieved according to an aspect of the invention considered to be independently inventive by providing a virtual library of patrice designs in the form of basic types, which comprises ground abutments in the corresponding regions (anterior tooth, canine tooth, posterior tooth, upper jaw and lower jaw). It is advantageous if there are preferably a number of patrice dimensions per region. The practitioner then only has to prepare the tooth stumps in such a way that one of the virtually provided library patrice caps with sufficient material thickness would fit over this ground tooth stump. In a CAD-CAM process, it is then possible to position the patrice caps of all abutments on the ground tooth stumps in optimal alignment with one another and to manufacture them accordingly.

[0075] To make this possible, one aspect of the invention provides that the practitioner either grinds the teeth intended as abutments in advance, as if they were about to apply a crown and / or bridge. Alternatively, they can scan them using an intraoral scanner (alternatively, a situation model could be created using a conventional impression, which is then digitized using a scanner). Preferably, the entire jaw is scanned. Software then calculates for which male copings (for which prefabricated matrices should then be available) the practitioner needs to remove the least amount of tooth structure, i.e., requires the least amount of grinding of the tooth or stump, or which male copings would fit directly onto the initially prepared tooth stumps.If a complete intraoral scan is available, the software can also take into account the optimized insertion direction as described above. The program then shows the practitioner on a screen which shows how much needs to be removed, ground or ground away from which tooth or stump. Ideally, no further grinding will be necessary after the initial preparation; otherwise, the practitioner can begin grinding now. For control purposes, the practitioner can perform another intraoral scan after completing the first grinding process. This time it is only necessary to capture the ground tooth and the immediate surrounding area in order to be able to make a statement about the achieved shape. If this is not sufficient, the software will indicate this and prompt the practitioner to perform another, complete jaw scan.In this way, the practitioner can iteratively grind the teeth or stumps until the preparations have a dimension such that the corresponding male coping fits onto the tooth stump with its minimum wall thickness.

[0076] According to aspects of the invention, the selection of a male body considered suitable and / or the combination with the other male bodies as well as the creation of a recommendation for action for the practitioner can be carried out based on one or more of the criteria listed below:

[0077] - the male body should be able to be attached in such a way that their respective longitudinal axes are aligned largely parallel to each other after attachment in the oral cavity, whereby for the respective male body the angle between its longitudinal axis and the parallel alignment should preferably be at most 15°, preferably at most 10° and particularly preferably at most 6°

[0078] - the required removal of tooth substance should be as low as possible for each individual male body and / or for the ensemble of all male bodies

[0079] - the or each male body should be as small as possible.

[0080] The exchange of information during grinding—i.e., where and how much needs to be removed or ground away—can also be achieved using other preparation testing techniques. It is particularly worth mentioning that there are methods that, in addition to the oral situation, also record the position of the contra-angle handpiece including the grinding tool, and can thus even record the change in shape of the tooth or tooth stump during tooth preparation. This is displayed to the practitioner on a monitor, allowing the preparation step to be optimized in terms of time. Thus, a repeat scan of the tooth or tooth stump is only necessary after preparation is complete for a final check.

[0081] Finally, according to one aspect of the invention, either a conventional impression or an intraoral scan of the entire jaw can be taken. Subsequently, the tooth stumps are overlaid with the corresponding male copings using CAD-CAM software. This results in corresponding male copings with a virtually prefabricated outer design (suitable for prefabricated matrices) and a corresponding inner design tailored to the tooth stump (suitable for the individually ground tooth stump). These hybrid male copings (prefabricated on the outside - customized on the inside) can then be manufactured in a grinding process from the green compact, white compact, or a pre-sintered ceramic and subsequently sintered if necessary.In a particularly cost-effective variant, there are appropriate form cutters for the milling process for the exterior design of the virtual prefabricated male molds to optimize accuracy, surface quality, and production speed. These male molds can, of course, also be made of a metal (titanium, zirconium, tantalum, or an alloy with a primary component of one of these metals), a non-precious metal alloy (e.g., chromium-cobalt-molybdenum), or a precious metal alloy. Other machining processes or additive processes, such as laser sintering or similar processes, are also suitable for production.

[0082] If a CT scan, a DVT, or another 3-dimensional acquisition system (e.g., MRI) is performed prior to preparation, it is possible to capture the cavities of the tooth root, i.e., the root canals, of the teeth or tooth stumps to be ground. In a particularly advantageous embodiment, this data can be overlaid with the intraoral scan to prevent the removal of tooth hard substance required to place the selected male cap from being so extensive that a perforation of the root canal occurs. This would cause significant damage to the tooth, which would be associated with root canal treatment, so that, according to one aspect of the invention, a different male cap with a smaller space requirement is selected instead.

[0083] In addition, it is also possible to evaluate existing 3-dimensional data about teeth, for example using artificial intelligence (Kl), in order to be able to make a statement about the probability of a root canal perforation using only the intraoral scan. In this case, the overall system would also be able to anonymously document whether or not a root canal perforation has occurred using artificial intelligence (Kl). This data could then be made anonymously available to all other users via the system with an appropriate internet connection in order to further optimize system security. The dental technician can then complete the entire prosthesis on his model. The finished prosthesis can deviate from the actual patient situation in the positions of the patrices relative to the matrices by a range of, for example, 50pm to 250pm.The introduction of the comparatively soft, in particular thermoplastic layer or the thermoplastic intermediate body provided according to one aspect of the invention is able to compensate for this. In order to achieve this compensation, the thermoplastic layer should preferably have a corresponding thickness of at least 250 μm around the layer surrounding the male part. During insertion into the patient's mouth, one aspect of the invention provides for the thermoplastic layer to be thermally brought above the softening point or softening interval so that it is deformable. If the prosthesis is then inserted into the patient's mouth and the patient bites down, the female parts "floating" in the softened thermoplastic layer or the softened thermoplastic intermediate body align themselves precisely with the male parts.After cooling, the thermoplastic layer solidifies again, and the aligned positions of the matrices are retained. This process can be repeated several times as needed, even after extended wear.

[0084] Before the final prosthesis or prosthetics are developed, the patrix designs to be used later are preferably defined in CAD during the grinding of the tooth stumps, in a development of the method considered to be independently inventive. Patrice designs already available in CAD for which corresponding matrices are available are selected. According to one aspect of the invention, these are aligned for an optimized insertion direction of the finished prosthesis or prosthetic based on the data of the oral situation (remaining dentition, mucous membrane, opposing jaw) acquired via the intraoral scanner, and are aligned with the ground tooth stump. The surfaces of the existing patrix designs from the library are combined or merged with the surface resulting from the tooth preparation. This creates a virtual copy of the cap to be manufactured, which can then be fabricated.This cap forms a matrix opposite the tooth stump and a patrix opposite the denture or prosthetic, which engages the matrix of the detachable connection to the denture or prosthetic. In extreme conditions where the teeth cannot be extensively prepared or reworked, it is possible to use a matrix system in which no intermediate body can be used for compensation during insertion, as the dimensions for a sufficient prosthetic are not available. For such a case, according to an aspect considered to be independently inventive, matrices are provided in which the inner cap is directly connected to the outer cap of the matrix in the buccal-palatal or buccal-lingual plane. The reason for this is that this system has a significantly smaller dimension.In the mesio-distal plane, however, an intermediate body is then provided for elastic deformation for the locking or snap-in mechanism provided as a connection mechanism according to one aspect of the invention. This soft and deformable intermediate body is preferably located in a compensation space that enables snapping onto the patrix. In this case, the contact layer also has the bulge in the matrix system only in the mesio-distal direction, since there is sufficient space in the prosthesis in this direction without this resulting in functional or aesthetic limitations. Depending on the wall thickness and the flexibility of the contact layer material, the compensation space can also be designed without a filling. In this cap system, which is considered inventive in its own right, the matrices should preferably be glued or cemented intraorally.

[0085] According to one aspect of the invention and in a configuration considered to be independently inventive, it can be provided that the complete dental prosthetic system is digitally planned based on the acquired intraoral data. Advantageously, a physical 3D model of the actual dentition situation in the patient's mouth is created based on the acquired intraoral data. The selected male parts can be temporarily attached to this model in their target position determined by the digital planning, with the removable dentures being fabricated based on the resulting assembly. In a particularly advantageous configuration considered to be independently inventive, the 3D model and / or the removable dentures are fabricated using 3D printing.

[0086] The concept of printing prosthetics using 3D printing is considered inventive in its own right. A physical 3D model of the actual remaining dentition in the patient's mouth can be created, preferably based on recorded intraoral data. It is advantageous to print the patrixes on the natural teeth or to print spacers into which the prefabricated patrixes can be inserted. Alternatively, the prepared tooth stumps can be printed and the corresponding, already manufactured patrixes temporarily attached. The selected matrices can be attached to these patrixes, if necessary after interrupting the printing process appropriately. The resulting intermediate body can then be coated with a suitable release agent, such as a material strip, if necessary and apart from the attached matrices, and the removable denture can be fabricated from the resulting assembly.The 3D printing software now needs to receive a signal that the matrices have been plugged in. This way, the plugged-in matrices are directly connected to the prosthesis during printing and do not need to be inserted into the prosthesis or glued to it afterward.

[0087] It is advantageous if the separating material used does not create a material bond between the prosthesis and the 3D model of the dentition situation, so that the prosthesis can be easily removed and is therefore ready for use in the patient's mouth.

[0088] The teeth can be printed during the fabrication of the prosthetics. Alternatively, they can be fabricated separately, for example, from a different material than the rest of the prosthetics to meet increased hardness and strength requirements. In this case, the teeth or denture bodies can be appropriately inserted into the prosthetic body later (in this case, preferably corresponding to the "red area" of the denture).

[0089] An alternative approach, considered to be independently inventive, can take into account the fact that, in an unfavorable oral situation, the prosthesis could jam, for example, due to unfavorably positioned tissue portions in the oral cavity. To avoid this, an aspect considered to be independently inventive can simply fabricate a type of "framework" that contains the male or female mold bodies or placeholders for them in the correct positions and in the correct orientations, or the corresponding tooth stumps, at the determined positions. The soft substance of the prosthesis can then be added separately if necessary and can be made of a correspondingly soft material.In a further development of the method for producing a dental prosthesis, which is regarded as independently inventive and which is particularly preferred for attachment to a dental implant, the exact position and orientation of the inserted dental implant is recorded when the intraoral data for the dentition situation is recorded, wherein the abutment intended for attachment to the implant is also suitably planned and manufactured on the basis of this data and taking into account the selected male element. In other words, in this embodiment, which is regarded as independently inventive, a model for the tooth stumps or tooth / abutment arrangements, in particular where these can be glued or introduced in some other way, can be provided. In this aspect of the invention, a framework is thus provided in which these supports are contained. The framework advantageously has four such supports, but can alternatively also have any other desired number, e.g.E.g. two or 6 or 8.

[0090] The advantages achieved by the invention are, in particular, that a system with reproducible adhesive force that is hardly dependent on chewing force and a particularly high degree of accuracy can be provided with particularly low expenditure. The system exhibits very little wear, particularly due to the extremely high degree of accuracy that can be achieved. Highly precise fits for a high level of wearing and chewing comfort can be achieved, and handling is simple and straightforward, i.e., the dental technician can fix the matrix in the prosthesis with minimal inaccuracy in the patient's mouth. Furthermore, the system has a particularly small footprint.

[0091] An embodiment of the invention is explained in more detail with reference to a drawing. In the drawing:

[0092] FIG. 1 shows a dental prosthesis designed as a removable denture,

[0093] FIG. 2 shows a longitudinal section through a telescopic crown for securing the denture according to FIG. 1,

[0094] FIG. 3 shows a telescopic crown according to one aspect of the invention in longitudinal section,

[0095] FIG. 4 shows a matrix element of the telescopic crown shown in FIG. 3 in an exploded view in perspective partial section (FIG. 4a) and in longitudinal section (FIG. 4b), FIG. 5 shows a sequence of assembly steps of the matrix element shown in FIG. 4 in longitudinal section,

[0096] FIG. 6 shows a side view of a male element of the telescopic crown shown in FIG. 3, and an inner cap of the female element, whose inner contour is adapted to the outer contour of the male element shown in FIGS. 4, 5,

[0097] FIG. 7 shows a male element and the associated female element in pairs in different cross-sectional geometries,

[0098] FIG. 8 shows the die element according to FIG. 5d with a tilted outer cap,

[0099] FIG. 9 shows an alternative embodiment of a matrix element in longitudinal section,

[0100] FIG. 10 shows a section of a heater,

[0101] FIGS. 11-15 each show an enlarged view of a contact plug of the heater according to FIG. 12,

[0102] FIG. 16 a dental implant,

[0103] FIG. 17 a telescopic crown attached to a dental implant,

[0104] FIG. 18 shows a further alternative embodiment of a telescopic crown intended for mounting on a dental implant in longitudinal section,

[0105] FIG. 19 shows the telescopic crown according to FIG. 18 in exploded perspective view,

[0106] FIG. 20 shows the telescopic crown according to FIG. 18 in exploded view in partial section,

[0107] FIG. 21 some variants of a male element mounted on an implant connecting screw,

[0108] FIG. 22 shows a further embodiment of a connection system, FIG. 23 shows a matrix element of the connection system according to FIG. 22,

[0109] FIG. 24 shows another embodiment of a matrix element,

[0110] FIG. 25 shows another embodiment of a matrix element,

[0111] FIG. 26 shows a sequence of assembly steps of the die element as shown in FIG. 25.

[0112] FIG. 27 shows an alternative embodiment of a telescopic crown in exploded view,

[0113] FIG. 28 the telescopic crown according to FIG. 27 in partially assembled condition,

[0114] FIG. 29 the telescopic crown according to FIG. 27 in fully assembled condition,

[0115] FIG. 30 shows a crown body in different views,

[0116] FIG. 31 shows another embodiment of a telescopic crown in exploded view,

[0117] FIG. 32 the telescopic crown according to FIG. 31 in cross section,

[0118] FIG. 33 the telescopic crown according to FIG. 31 in partially assembled condition,

[0119] FIG. 34 shows the telescopic crown according to FIG. 31 in a fully assembled state,

[0120] FIG. 35 shows another embodiment of a telescopic crown in exploded view,

[0121] FIG. 36 the telescopic crown according to FIG. 35 in cross section,

[0122] FIG. 37 the telescopic crown according to FIG. 35 in partially assembled condition,

[0123] FIG. 38 the telescopic crown according to FIG. 35 in fully assembled condition,

[0124] FIG. 39 shows an inner cap of a telescopic crown of the type described above, and FIG. 40 shows a matrix element of a telescopic crown of the type described above with an inner cap, as shown in FIG. 39.

[0125] Identical parts are provided with the same reference numerals in all figures.

[0126] The dental prosthesis 1 shown in FIG. 1 is designed as a removable dental prosthesis 1 and thus for removable attachment in the oral cavity of a patient. In the exemplary embodiment, a complete upper jaw prosthesis is shown as the dental prosthesis 1; alternatively, however, other prostheses could of course also be provided, such as a bridge that closes a gap between several teeth of a remaining dentition, or even individual prostheses to replace a single tooth. The dental prosthesis 1 comprises a prosthesis body 2, which has artificially produced teeth and is designed for detachable connection to a number of supporting pillars firmly arranged on the upper jaw 4 and thus in the oral cavity of the patient. In the exemplary embodiment shown, the supporting pillars are teeth 6 of a remaining dentition that remain in the patient's oral cavity and whose surfaces have been suitably ground down; alternatively, however, inserted dental implants could also be provided for this purpose.

[0127] The removable dental prosthesis 1 comprises a number of fastening systems 10 - in the exemplary embodiment corresponding to the number of ground teeth 6 of the remaining teeth - with which the prosthesis body 2 is removably fastened to the upper jaw 4 and thus in the oral cavity of the patient. The respective fastening system 10 can, according to one aspect of the invention, be designed as a so-called telescopic crown, as is shown in a conventional design in longitudinal section in FIG. 2a in a single version and in FIG. 2b in longitudinal section as a fastening means for the prosthesis body 2. Such a telescopic crown essentially represents a double crown system. On the one hand, this comprises a "lower" or base crown 12, also referred to as the "primary crown", which is firmly attached in the manner of a conventional crown to a suitably prepared, e.g. ground, tooth 6 or also to an inserted dental implant. The primary crown 12, which is also shown in FIG.1 for the teeth 6 shown there, is shown in the illustrations in FIG. 2 in the state attached to the respective tooth 6.

[0128] The primary crown 12 is designed, in a quite conventional manner, as a male element 14, which forms a contact pin 16 on its surface. An "upper" crown segment or female element 18, also referred to as a "secondary crown" in the case of the fastening system 10 being designed as a telescopic crown, can be attached, for example, by clicking or plugging onto the male element 14 as a second essential component of the respective fastening system 10. In FIG. 2a, the sliding-on process is indicated by the arrows 20, whereas in FIG. 2b, the fastening system 10 is shown in the state with the female element 18 completely pushed onto the male element 14.In the type of matrix-pattern system of the fastening system 10 formed by the elements 14, 18, the “upper” fastening element 18 forming the matrix serves as a support for the prosthesis body 2, which is suitably firmly connected to the matrix elements 18.

[0129] For removable dentures 1 of the type described, the accuracy of fit of the prosthesis body 2 in the patient's mouth is an important factor, since a high level of fit is a prerequisite for a secure fit of the prosthesis 2 in the patient's mouth. Furthermore, a high level of fit naturally also requires a high level of comfort for the patient, so that they can feel as good as possible with the prosthesis 2. The more precisely the prosthesis is manufactured, the more firmly it can fit in the patient's mouth, which in turn leads to very high levels of comfort when worn and chewed. However, with regard to common manufacturing methods, which usually first determine the dental situation in the patient's mouth and then transfer it to a physical or virtual model, based on which the restoration is then planned and manufactured, undesirable inaccuracies in the fit are to be expected.

[0130] Furthermore, for such a removable dental prosthesis 1, it must be taken into account that, precisely because of the repeated removal and reinsertion in the area of ​​contact between the male elements 14 and the female elements 18, increased stress and thus increased wear are to be expected.

[0131] To accommodate both of these aspects, one aspect of the present invention provides a design for the respective fastening systems 10, as will be explained in more detail below using the telescopic crown 30 as an embodiment. Such a telescopic crown 30, which allows for a particularly precise manufacture of the fastening system 10 with a high degree of durability, is shown in longitudinal section in FIG. 3. The inventive design of the fastening system 10 is based on the concept of manufacturing the essential components of the connection area with an accuracy considered acceptable and then, after pre-assembling the components, inserting them into the patient's mouth with a certain degree of flexibility and formability.There, in response to the actual oral situation and the restoring and shear forces occurring during insertion, it should be possible to adapt the final positioning of the components to the actual oral situation, which can then also be fixed according to a preferred aspect of the invention.

[0132] For this purpose, the connection system in one aspect of the invention, as shown in FIG. 3 with reference to the embodiment as a telescopic crown 30, comprises, as essential components comparable to the conventional design of a telescopic crown, on the one hand, a male element 14 intended for mounting or crowning on a residual tooth 6 or on a dental implant, and on the other hand, a corresponding female element 18 that can be plugged onto the male element 14 and firmly connected to the prosthesis body 2. In contrast to the conventional design of a telescopic crown, according to one aspect of the present invention, the female element 18 is designed in several parts. It comprises an inner cap 32 that can be plugged onto the male element 14 and forms a contact surface 31 for the associated male element 14.According to one aspect of the invention, this inner cap 32 is made of a comparatively hard plastic in the region of the contact surface 31 and is attached to the prosthesis body 2 via an intermediate body 36 made of a comparatively softer material, in particular a softer plastic. To create a locking or snap-in connection, the male element 14 is provided with an external groove 37. On the contact surface 31 of the inner cap 32, a corresponding inner bead 38 is provided on the inside, which engages in the groove 37 of the male element 14.

[0133] In one embodiment of the invention, the intermediate body 36 could be attached directly to the prosthesis body 2, i.e., the intermediate body 36 could be introduced directly onto the prosthesis body 2 and fixed there, for example, by a material fit, i.e., glued or cemented. In an alternative embodiment shown in the present example, however, the intermediate body 36 is attached indirectly to the prosthesis body 2, in the sense that the matrix element 18, when the attachment system 10 is designed as a telescopic crown 30, additionally comprises an outer cap 34 attachable to the prosthesis body 2. In this embodiment, the intermediate body 36 is arranged in the space between the inner and outer caps 32, 34. This multi-part design of the matrix element 18 is particularly clearly visible from the exploded view in FIG. 4 and the sequence of assembly steps in longitudinal section in FIG. 5.

[0134] During the assembly of the matrix element 18 shown in FIG. 5, the intermediate body 36 is first inserted into the outer cap 32 shown in FIG. 5a, as shown in FIG. 5b. This intermediate body 36 has a circumferential end bead 40 at its free end 39, which is inserted into a receiving groove 42 formed on the end of the inner cap 32 during the insertion of the inner cap 32 as shown in FIG. 5c. The partially assembled ensemble 44 consisting of the inner cap 32 and the intermediate body 36 resulting from this insertion could also be provided separately according to one aspect of the invention, inserted directly into the prosthesis body 2 and fixed there. In the exemplary embodiment shown, however, according to an alternative aspect for providing the telescopic crown 30, this partially assembled ensemble 44 is inserted into the outer cap 34, so that the ensemble 46 shown in FIG. 5c is created.In the illustrated embodiment, a circumferential fixing edge 48 formed in the end region of the inner cap 32 is inserted into a receiving ring 50 of the outer cap 34. A flanged edge 52 surrounding the inner cap 32 is then folded over to form a crimped or flanged connection, so that, as shown in FIG. 5d, it encloses the fixing edge 48 and thus sufficiently fixes the inner cap 32 to the outer cap 34 in the sense of pre-assembly. The die element 18, shown in FIG. 5e in an external view, is thus completed.

[0135] The combination of the inner cap 32 with the intermediate body 36 and the resulting material pairing of a comparatively hard plastic for the inner cap 32 with a comparatively soft material for the intermediate body 36 are each considered to be independently inventive. In particular, this combination makes it possible, on the one hand, to provide a particularly stable and wear-resistant connection to the associated male element 14 in the region of the contact surface 31, while, on the other hand, the comparatively soft and thus deformable intermediate body 36 allows for flexible adaptation of the more detailed positioning to the requirements of the oral situation. This aspect of the invention is just as advantageous for the design of a direct connection of the intermediate body 36 to the prosthesis body 2 as it is for the corresponding design as a telescopic crown 30 with an associated outer cap 34.

[0136] According to one aspect of the invention, a plastic is provided as a particularly favorable base material for the intermediate body 36; according to aspects of the invention, ethylene-vinyl acetate copolymer, polyethylene, polypropylene, polyolefin, or polyamide can preferably be considered particularly suitable. These are, in particular, materials for the intermediate body 36 with a tensile modulus of elasticity of less than 100 MPa. Furthermore, in aspects of the invention, the intermediate body 36 alternatively or additionally has a tensile modulus of elasticity of approximately 65 MPa, an elongation at break of more than 50%, a yield stress of 5-10 MPa, and / or a tensile strength of 10-20 MPa.

[0137] However, according to aspects of the invention, the plastic forming the inner cap 32 should have comparatively high abrasion resistance and mechanical strength, so that repeated removal and reinsertion of the dental prosthesis 1 is possible even without significant wear of these components. Therefore, in the exemplary embodiment, PEEK is provided as the base material for the inner cap 32 and in particular the contact surface 31 formed by it. This plastic, in particular with a tensile modulus of elasticity of approximately 4210 MPa, satisfies the aforementioned "hard plastic" criterion.

[0138] The base material polyetheretherketone (PEEK), which is considered particularly suitable, also has, for example, a tensile strength of 110 MPa, a flexural strength of 170 MPa and an elongation at break of 11% and a tensile modulus of elasticity of 4210 MPa.

[0139] Due to the aforementioned material choices and the resulting material pairing of PEEK for the inner cap 32 or the contact surface 31 formed thereby, on the one hand, and ethylene-vinyl acetate copolymer for the intermediate body 36, the ratio of the tensile moduli of elasticity of the intermediate body 36 to the inner cap 32 of less than 1:10, preferably less than 1:25, and particularly preferably less than 1:50, preferably provided according to one aspect of the invention, is also maintained in the exemplary embodiment; in this case, it is approximately 65:4210 or 1:65.

[0140] This multi-part design using an at least temporarily deformable intermediate body 36 or a temporarily deformable intermediate layer thus makes it possible for the final positioning and alignment of the components to one another, i.e. in particular in the design as a telescopic crown 30 of the inner cap 32 and outer cap 34 or in the design with "direct fixation" of the inner cap 32 and prosthesis body 2, to only take place during the insertion of the dental prosthesis 1 into the oral cavity. As part of the preparation for insertion, the outer cap 34 or the intermediate body 36 can thus already be firmly mounted on the prosthesis body 2. In the exemplary embodiment, the design of the intermediate body 36 provided according to a preferred aspect is also implemented as a thermoplastic elastomer material.According to this aspect of the invention, for insertion, the thermoplastic intermediate body 36 is first heated to above its softening temperature so that it is deformable. In this state, insertion can then take place so that the inner and outer caps 32, 34, or the inner cap 32 and the prosthesis body 2, are suitably aligned with one another according to the fine details of the oral situation and in response to the resulting pressure and positioning forces, with the intermediate body 36 deforming. The alignment of the inner cap 32 relative to the outer cap 34, or analogously relative to the prosthesis body 2, and thus the final positioning, is thus adapted to the actual conditions in the oral cavity. The intermediate body 36 can then cool down and subsequently solidify again while retaining its assumed shape and thus maintaining its underlying position.After solidification, the optimized alignment of the components recorded in this way is fixed.

[0141] According to one aspect of the invention, the intermediate body 36 is preferably specifically adapted to the usual handling processes for use in dental treatments with regard to its choice of material and its material parameters. In particular, it is advantageously taken into account that autoclaving is common and widespread in such processes. According to one aspect of the invention, the material parameters of the intermediate body 36 are selected such that, at the usual temperatures during such autoclaving, thermoplastic softening does not occur at all or, with regard to thermal inertia, at least not during the treatment in the autoclave, so that even with such autoclaving, the position of the inner cap 32 facing the male part 14 relative to the position of the outer cap 34 facing the prosthetic body 2 orthe prosthetic body 2 as such is not changed and the position previously introduced according to the concept of the invention is also not changed during autoclaving. The softening temperature of the thermoplastic intermediate body 36 is accordingly selected, in particular through suitable material selection, in this embodiment above approximately 135°C. This is namely the temperature of common and conventional autoclaves, with which, for example, prostheses are autoclaved for preparation for use or for disinfection. If necessary, softening temperatures of at least 60°C can also be considered sufficient for the intended treatment. In this context, it would be crucial that the decomposition temperature of the material used, preferably a plastic, is above 135°C.

[0142] Analogously, a material with similar properties, but not plastic, could be chosen for the intermediate body. In this case, too, softening should not occur until a temperature of approximately 60°C is reached.

[0143] The male element 14 of the telescopic crown 30 is shown in a side view in FIG. 6a. In the exemplary embodiment, the male element 14 has a substantially round cross-section, although it can alternatively be designed with non-round cross-sections, for example oval, elliptical, trioval, or the like, preferably adapted to the geometric conditions at the insertion site in the oral cavity. As can be clearly seen from the illustration in FIG. 6, the male element 14 has a circumferential groove 37 on its contact surface 33 intended for connection to the contact surface 31 of the inner cap 32. In interaction with an associated inner bead 38 on the inside of the inner cap 32, this groove ensures retention when the inner cap 32 is applied and thus provides additional fixation.Thus, the connection system 10 can be designed in the manner of a snap-in or locking connection, in which the female element 18 can be clicked or snapped onto the male element 14 via its inner cap 32. As can be seen from the illustration in FIG. 6b, the inner contour of the inner cap 32 is adapted to this. In particular, the material pairing of the inner cap 32 on the one hand and the intermediate body 36 on the other hand also makes it possible to provide a type of resilient locking connection between the female element 18 and the male element 14. While the inner cap 32 is pushed onto the male element, the inner bead 38 is compressed by contact with the male element 14, whereby the comparatively soft intermediate body 36 is deformed accordingly.As soon as the inner bead 38 is located in the area of ​​the groove 37, the temporarily deformed intermediate body 36 can reset itself in this area so that the inner bead 38 engages in the groove 37.

[0144] FIG. 7 shows a number of additional geometric variants for the male element 14 in combination with the associated female element 18 with differently designed cross-sectional contours in a perspective view, as examples, which can be selected as needed depending on the insertion site and the patient's oral situation. The male element 14, on the one hand, and the complete telescopic crown 30, i.e., the female element 18 mounted on the male element 14, are shown together in pairs. In particular:

[0145] FIG. 7a shows a male and female element 14, 18 with a non-round, oval or elliptical cross-section,

[0146] FIG. 7b shows a male and female element 14, 18 with a trioval cross-section,

[0147] FIG. 7c a male and female element 14, 18 with quadoval cross-section,

[0148] FIG. 7d shows a male and female element 14, 18 with an elongated rectangular cross-section with rounded corners to meet the ovality criteria,

[0149] FIG. 7e a male and female element 14, 18 with a comparatively “flat”, elongated cross-section,

[0150] FIG. 7f shows the male and female elements 14, 18 according to FIG. 7e with an additional, partially circumferential undercut or groove 37 to provide additional retention.

[0151] A variant considered to be independently inventive is shown in FIG. 7f. There, the retention provided due to the geometry is, according to this aspect of the invention, primarily intended in a mesio-distal orientation so that the caps or elements of the matrices 18 on the stumps / abutments can be designed with comparatively thin walls in the buccal-palatal or buccal-lingual plane. The space required for the retention elements is kept particularly small in the patrix element 14, in particular in the direction transverse to the mesio-distal direction, in which the space available is particularly small. In order to nevertheless enable reliable retention, in this particularly preferred embodiment the groove 37 or undercut is only provided in the front and rear region, viewed in the mesio-distal direction, where sufficient space is available. In this configuration, according to one aspect of the invention, the groove 37 orThe undercut, viewed in plan view, is thus limited to a partial segment of the contact surface 33 of the male element 14 intended for alignment in the mesio-distal direction in the patient's mouth.

[0152] The matrix element 18 described above is heated during insertion, as mentioned above, so that the intermediate body 36, which in this embodiment is thermoplastic, is heated above its softening temperature and thus becomes deformable. In this state, insertion can then be carried out, so that the inner and outer caps 32, 34 or the inner cap 32 and the prosthesis body 2 are suitably aligned with one another according to the fine details of the oral situation and in response to the resulting pressure and positioning forces, with deformation of the intermediate body 36. As a result of this alignment, the inner cap 32, starting from the initially approximately parallel alignment as shown in FIG. 5d, is tilted or otherwise repositioned relative to the outer cap 34, whereby the intermediate body 36 is deformed accordingly. The result of such deformation, which is accompanied by the final alignment of the components, is shown by way of example in FIG.8 shows a longitudinal section of the matrix element 18 in the "tilted" state. Of course, a similar tilting can also occur when the intermediate body 36 is directly attached to the prosthesis body 2, resulting in a corresponding tilting between the inner cap 32 and the prosthesis body 2.

[0153] In comparison to the starting position (see FIG. 5d), the deformation that has occurred in the intermediate element 36 is clearly visible. It is equally evident, however, that the inner cap 32 is also significantly deformed in the region of the fixing edge 48 forming its base. According to an aspect considered to be independently inventive, this intended deformation of the inner cap 32 is taken into account by a suitable choice of material. The base region or fixing edge 48 of the inner cap 32, which forms a kind of membrane, should offer as little or no restoring force against this deformation as possible. According to one aspect of the invention, this is achieved by a suitable choice of material for the inner cap 32, at least in the region of the fixing edge 48. For this reason, the inner cap 32 is preferably made of a high-performance plastic, preferably PEEK.

[0154] According to one aspect of the invention, it is considered particularly important in this context that the material of the inner cap 32 should have a significantly higher softening temperature than that of the intermediate body 36. In this case, a softening temperature ratio between the intermediate body 36 and the inner cap 32 of less than 1:1.5, preferably less than 1:2 and in particular less than 1:3 is provided. Furthermore, the wall thickness of the inner cap 32 should be small in relation to the intermediate body 36 in this case. Firstly, in order to keep the temperature permeability through the inner cap 32 particularly high, and secondly, in order to make the space available for the alignment of the components to one another made possible via the intermediate body 36 as large as possible. In this case, a ratio of the layer thicknesses between the intermediate body 36 to the inner cap 32 of greater than 1:1, preferably greater than 2:1 and in particular greater than 3:1 is particularly preferred. In FIG.Figure 9 shows an alternative embodiment of a matrix element 18' in longitudinal section. In this variant, the cover region 54 of the inner cap 32' is corrugated, so that a certain deformability is provided, particularly in the longitudinal direction. Such a design thus enables a certain extent of compensation or equalization of the positions of the components relative to one another in the longitudinal direction. A further alternative for such position compensation is a variant in which a compressible material or even air is incorporated in the region of the intermediate body 36. Spatially speaking, this can affect the entire intermediate body 36 or only a part or an area between the outer cap 34 and the inner cap 32.

[0155] In order to enable the heating of the thermoplastic intermediate piece 36 of the fastening systems 10 to a temperature above the softening temperature immediately before insertion, as provided in one aspect of the invention, particularly when the intermediate body 36 is designed as a thermoplastic component, a heating device 60 is provided according to one aspect of the invention, a section of which is shown in FIG. 10. The heating device 60 comprises a number of heatable contact plugs 62, the outer contour of which corresponds to the contour of the male elements 14 of the fastening systems 10 and can thus be inserted into the female elements 18 or their inner cap 32 instead of the male elements 14, and of which only one is shown in FIG. 10. The contact plugs 62 are therefore preferably designed to be as geometrically identical as possible to the actual male elements 14.According to one aspect of the invention, small grooves can be provided in the axial direction in the outer skin of the contact plugs 62 to facilitate removal of the heated die elements 18, so that no negative pressure can form after heating during removal. If the thermoplastic intermediate bodies 36 are heated, removal could lead to damage if negative pressure is present.

[0156] The contact plugs 62 can therefore also be referred to as “heating patrices”. For optimized heat dissipation, they are preferably made of a metal, preferably with a high thermal conductivity, in particular aluminum, copper or silver, or also of a metallically coated variant made of one of the aforementioned metals. For heating, the respective matrix element 18 can then be plugged onto one of these contact plugs 62, and subsequently, by heating the contact plug 62, the thermoplastic intermediate body 36 of the matrix element 18 can be heated to a temperature above its softening temperature. The heating device 60, which is regarded as being independently inventive, is connected to a heating element 62 which corresponds to the number of matrix elements 18 or 20 provided in the respective dental prosthesis 1.the number of matrix elements 18 usually used in such dental prostheses 2, preferably two to eight, particularly preferably four to six of the said heating elements or contact plugs 62, so that all matrix elements 18 of a dental prosthesis 2 can be heated simultaneously and thus prepared for insertion.

[0157] The possibility of inserting the contact plugs 62 into the inner cap 32 of a matrix element 18 is particularly clear from the various enlarged illustrations in Figures 11 to 15.

[0158] In the exemplary embodiment, the heatable contact plugs 62 are provided with an integrated heating element 64 with integrated temperature control. By applying a defined amount of heat energy over a defined period of time, the amount of heat required to soften the intermediate body 36 can be introduced into the intermediate body 36 or the thermoelastic layer, enabling the fine alignment of the inner cap 32 facing the male elements 14 relative to the outer cap 34 connected to the prosthesis 2. Furthermore, a handle 66 is preferably formed behind the actual heating male element 62 to allow the heating male elements 62 to be easily inserted into the female elements 18 and removed again. These handles 66 are preferably designed so that they can be inserted and removed using the thumb and index finger.

[0159] The heating elements 64, designed as internal electrical heaters, ensure that overheating and thus damage to the matrix-pattern system or the prosthesis body 2 itself cannot occur. This control requires that temperature sensors 68 are integrated into the heating patrixes 62. Alternatively, the heating patrixes 62 could also be equipped with another heat source or be supplied via an external heat source. Furthermore, it is also possible for the heating patrixes 62 to simply heat the thermoelastic intermediate body 36 via another energy source, without being heated themselves.

[0160] According to one aspect of the invention, a plurality of the heating male parts 62 are each connected via a cable connection 70 to a common, central temperature control unit (not shown in detail in FIG. 10). This unit preferably has four or six connections in order to be able to control four or six heating male parts 62 simultaneously. Alternatively, and depending on the intended use, such a unit could also be provided with a larger number of connections, for example with 2, 4, 6 or 8. According to one aspect of the invention, there should be at least as many as are usually provided with supporting pillars in a prosthesis 2. Preferably, the heating male parts 62 are provided directly with a cable connection 70, but are detachably connected to the central control unit via a plug.

[0161] In a particularly preferred embodiment, the heating elements 62 are equipped with rechargeable batteries that are located in a single charging station. The temperature control unit is integrated into the heating elements 62.

[0162] The above-described male elements 14, which interact with the matrix elements 18, can, as mentioned, alternatively be attached and anchored to teeth 6 still present in the patient's mouth or to inserted dental implants 72. Such a known dental implant 72 is shown in FIG. 16a in an exploded view, in FIG. 16b in a side view in the assembled state, and in FIG. 16c in a longitudinal section in the assembled state. It comprises, as essential components, the actual implant 74, also referred to as the "post part" 74, intended for insertion into the patient's jawbone, and an associated abutment 76, which can be attached to the post part 74 and, if necessary, is provided with an indexing feature 75 for correct rotational alignment.In the embodiment shown, the abutment 76 can be fixed to the post part via a separate connecting screw 78; however, it could also be provided directly with a molded screw thread in the manner of a one-piece design.

[0163] A telescopic crown 30 attached to the abutment 76 of such a dental implant 72 is shown in FIG. 17 in a side view (FIG. 17a), in longitudinal section (FIG. 17b), in an exploded view in a side view (FIG. 17c), and in an exploded view in longitudinal section (FIG. 17d). In this case, the telescopic crown comprises a matrix element 18 constructed identically to the above-described embodiment, which is constructed in several parts and essentially consists of the inner cap 32 provided for detachable connection to the male element 14' and the intermediate body 36. In this case, the male element 14' is formed by the abutment 76, which is correspondingly shaped in its head region. In the exemplary embodiment shown in FIG. 17, the variant of the design as a telescopic crown 30 is again shown, which additionally comprises the outer cap 34. As described above, the intermediate body 36 is arranged between the outer cap 34 and the inner cap 32.The inner cap 32 is in turn provided on the inside with an inner bead 38, which can snap into an associated groove 37 in the head region of the abutment 76 designed as an associated male element 14' and thus improve the retention.

[0164] The male element 14', which is considered to be independently inventive, is thus specifically designed for mounting as an abutment 76 on the post part 74 of the dental implant 72 in the embodiment shown in FIG. 17 and, for this purpose, is designed in its basal region 80 in the manner of an abutment 76 or superstructure part. For this purpose, it comprises a contact surface 82 in the basal region 80, the contour of which is adapted to an associated contact surface in the connection region of the implant 72 and can thus be placed thereon with a precise fit. In its central region, the male element 14' also has a screw channel 84 for the connecting screw 78, by means of which it can be fastened to the post part 74. In other words, in this embodiment, the male element 14' can be considered to be molded onto the abutment 76 of the dental implant 72.

[0165] Depending on the requirements of the patient's treatment, the male element 14', or in other words the head region of the abutment 76, can also be designed to be angled according to one aspect of the invention.

[0166] A further alternative embodiment of a telescopic crown 30 intended for mounting on a dental implant according to one aspect of the invention is shown in FIG. 18 in longitudinal section, in FIG. 19 in an exploded perspective view, and in FIG. 20 in an exploded partial section. This is essentially identical in construction to the telescopic crown 30 according to FIG. 17, but the connection system to the implant is modified. In this embodiment, a separate connecting piece 86 is provided for connection to the implant. In this case, the connecting piece 86 has the contact surface 82 in the basal region 80, the contour of which is adapted to an associated contact surface in the connection region of the post part 74 and can thus be placed thereon with a precise fit.In its central region, the connecting piece 86 has the screw channel 84 including the screw seat 88 for the implant connecting screw 78, by means of which it can be fastened to the implant 74. Above a platform surface 92 formed by the connecting piece 86, the screw channel 84 continues in the manner of a sleeve 94, which encloses the screw head 96 of the inserted connecting screw 78 and serves on the outside as a mounting surface for the male element 14". In this case, the male element 14" can be attached to the sleeve 94 and / or the platform surface 92 using conventional mounting techniques such as gluing or cementing.

[0167] The male element 14" can be designed to be closed in the area of ​​its cover surface 98 so that, after assembly, it completely encloses the screw head 96 of the connecting screw 90. Alternatively, it can also be designed to be perforated in the area of ​​the cover surface 98 and to leave an access opening 100 free, through which access to the screw head 96 is possible, for example, using a suitable (assembly) tool. In this regard, FIG. 21 shows several variants, each in pairs in a perspective view and in a perspective section, namely the closed variant (FIG. 21a), a variant with a comparatively small access opening 100 (FIG. 21b), and a variant with a comparatively large access opening 100 (FIG. 21c).

[0168] A further alternative embodiment of a connection system 10 with a telescopic crown 30 of the aforementioned design according to an aspect of the invention considered to be independently inventive is shown in FIG. 22, in pairs in a side view and in longitudinal section, in the assembled state (FIG. 22a) and in an exploded view (FIG. 22b). The matrix element 18' of this exemplary embodiment is shown in FIG. 23 in an enlarged longitudinal section. In this embodiment, the connection system 10 is provided for an abutment 76' which is formed integrally with the connecting screw 78; i.e., in this embodiment, the abutment 76' is formed with a molded-on screw thread 75.In particular, the fact that when screwing such an abutment 76' into the inserted post part 74, the rotational end position cannot usually be precisely specified is taken into account; rather, the screwing process will end depending on the precise insertion of the post part 74. Accordingly, according to one aspect of the invention, the abutment 76' is generally round in cross-section. It can also be combined with the connectable male element 14" shown in Figure 19.

[0169] Even in this embodiment, which is considered to be independently inventive, the matrix element 18', as can be clearly seen from the longitudinal section in FIG. 23, has a circumferential inner bead 38 on the inside of the inner cap 32, which engages in the circumferential groove 37 provided there to provide suitable retention when the inner cap 32 is applied to the male element 14', thus ensuring additional fixation. Thus, in this variant too, the connection system 10 can be designed in the manner of a snap-in or locking connection, in which the matrix element 18' can be clicked or snapped onto the male element 14' via its inner cap 32. In this embodiment, too, a resilient locking connection is to be provided between the matrix element 18' and the male element 14'.As the inner cap 32 is pushed onto the male element 14', the inner bead 38 is compressed by contact with the male element 14, whereby the comparatively soft intermediate body 36 is deformed accordingly. As soon as the inner bead 38 is located in the region of the groove 37, the temporarily deformed intermediate body 36 can return to its original position in this region, so that the inner bead 38 engages the groove 37. To suitably support this and also provide retention during the fixation of the female element 18' in the prosthetic, according to one aspect of the invention, the outer cap 34 in this embodiment is provided with a circumferential outer bead 102.

[0170] In an embodiment considered to be independently inventive, a circumferential groove 104 is provided on the inside of the outer cap 34, corresponding to this outer bead 102. In an embodiment considered to be independently inventive, this groove 104 can provide an escape space for the intermediate body 36, into which the intermediate body can deform. This can be particularly important in situations in which, during insertion, the inner cap 32 comes into direct contact with the outer cap 34 in some places, i.e., during "maximum" repositioning during the automatic adaptation of the system to the oral situation. Even in such a situation, the groove 104 locally provides an escape volume for the intermediate body 36, into which the intermediate body can deform, thus enabling the female element 18' to be clicked or snapped onto the male element 14'.The escape space formed by the groove 104 can be completely or partially filled with material of the intermediate body 36 or with another suitable, preferably soft, material or can also be kept completely empty.

[0171] A further embodiment of a matrix element 18", which is also considered to be independently inventive, is shown in FIG. 24 in a lateral view (FIG. 24a) and in longitudinal section (FIG. 24b). This is largely identical in construction to the matrix element 18' described above, but additionally has a further retention element 106 formed onto the outer cap 34 for even further improved anchoring in the prosthesis body 2. According to one aspect of the invention, this can already be formed onto or into the outer cap 34 during manufacture by suitable processing measures such as folding.

[0172] According to a further aspect considered to be independently inventive, the design of the inner cap 32 from a comparatively hard and durable plastic such as PEEK in particular can be specifically used to facilitate production of the matrix element 18. For this purpose, as can be seen from the exploded view in FIG. 25 in side view (FIG. 25a) and in longitudinal section (FIG. 25b) of a further matrix element 18"' considered to be independently inventive, the inner cap 32 can be designed to be extended in its end region instead of the fixing edge 48, so that a turned-over edge 108 is produced. As can be seen from the representation of a sequence of production steps of the matrix element 18'" in FIG. 26, in longitudinal section and in lateral view, the intermediate body 36 can first be inserted into the outer cap 34 (FIG. 26a) (FIG. 26b), before the inner cap 32 is subsequently inserted (FIG. 26c in longitudinal section and FIG.26d in side view). For fixing and final assembly of the matrix element 18'", the folded edge 108 can then be folded over, whereby it remains stable after folding due to the material properties of the inner cap 32 (FIG. 26e in longitudinal section and FIG. 26f in side view).

[0173] An alternative embodiment of a telescopic crown 30', which is regarded as being independently inventive, is shown in FIGS. 27 to 29 in an embodiment for attachment to a prepared tooth stump 6. FIG. 27 shows the telescopic crown 30' in an exploded view in a lateral view (FIG. 27a), in longitudinal section (FIG. 27b) and in a further lateral view rotated by 90° about the longitudinal axis compared to FIG. 27a (FIG. 27c). FIG. 28, on the other hand, shows the telescopic crown 30' in a partially assembled state in a lateral view (FIG. 28a), in a further lateral view rotated by 90° about the longitudinal axis compared to FIG. 28a (FIG. 28b) and in longitudinal section (FIG. 28c). Fig. 29 shows the fully assembled telescopic crown 30' in a side view (Fig. 29a), in a further side view rotated by 90° around the longitudinal axis compared to Fig. 29a (Fig. 29b) and in a longitudinal section (Fig. 29c).

[0174] According to one aspect of the invention and in a configuration considered to be independently inventive, the intermediate body 36 in the telescopic crown 30' is not designed as a complete body enclosing or encompassing the inner cap 32, but rather consists of a number, two in the exemplary embodiment, of partial bodies 112. These are selectively arranged only in a partial area on the circumference of the outer cap 34'. The partial bodies 112 are jaw-like and have comparatively small dimensions. Accordingly, viewed in the longitudinal direction, they extend only over a small portion of the longitudinal extent of the inner cap 32, as well as in the azimuthal or angular direction. Otherwise, i.e., over the largest portion of the lateral surface of the inner cap 32, the inner cap 32 rests directly against the inner side of the outer cap 34'.Such a system, with a simple structure, can offer enormous advantages in terms of functionality when establishing the connection between the dental prosthesis 1 and the male elements 14". To establish the connection and for the necessary retention between the male element 14" and the inner cap 32 of the female element 18', the male element 14" can be provided with a circumferential groove 37 on its contact surface 33, as described above. Correspondingly, in this exemplary embodiment, the inner cap 32 can also have inwardly facing cams 116 at a corresponding position or, if appropriate, a completely circumferential inner bead 38. In addition, according to one aspect of the invention, the outer cap 34" is also provided on the inside with a number of formations or pockets 118, into which the partial bodies 112 are each inserted, and which cause corresponding protrusions of the outer cap 34" on the outside.

[0175] When the inner cap 32 is pushed onto the respective male element 14", its outer contact surface 33 thus displaces the inner bead 38 or the cams 116, whereby the partial body 112 located behind it is deformed or compressed due to its comparatively soft material. This is supported by the choice of material, in particular PEEK, for the inner cap 32 in a manner considered inventive, since the selected material, due to its durability and its comparatively thin-walled design in the embodiment shown, significantly facilitates the displacement movement of the partial bodies 112 into the respectively associated pocket 118. As soon as the inner cap 32 is then sufficiently pushed on and the inner bead 38 or the cams 116 overlap with the groove 37, the respective partial body 112 largely returns to its original shape, so that the then newly formed inner bead 38 or the cams 116 engage in the groove 37.This creates retention between the male element 14" and the inner cap 32, and the female element 18" rests on the male element 14". Due to the choice of material, the snap-in or locking system 120 formed thereby is a resilient system, with the locking element 124 formed by the inner bead 38 or the cams 116 acting as a resilient locking element 124.

[0176] According to one aspect of the invention, the pockets 118 or the external bulges resulting from them offer a double advantage or benefit: on the one hand, they provide a receiving and compression volume for the sections 112 of the intermediate body 36, and on the other hand, they offer additional retention on the outside and thus storage security for the introduction and anchoring of the outer cap 34" in the prosthesis body 2.

[0177] A fundamental concept of the present invention is thus to provide a mechanism for a locking or snap-in connection for attaching a matrix element 18, 18', 18", 18"', 18"", 18 on a patrix element 14, 14', 14" for an abutment of a dental implant or a natural tooth, in particular in a telescopic crown 30, 30', in which the comparatively soft or deformable intermediate body 36 or partial body 112 interacts with an escape space, so that the bead 38, which interacts with the respective groove 37 to provide retention, can resiliently yield when needed to enable snapping or locking. The escape space provided for this purpose can be provided by a sufficiently voluminous intermediate body 36 or by the pockets 118, wherein the pockets 118 can be completely, partially, or not at all filled with the material of the partial body 112. can and if necessarycan also enclose additional air cushions. For this purpose, in the above and also in the following examples, the groove 37 is arranged in the male element 14, 14', 14", and the system of retention-providing bead 38 with associated intermediate or partial body 36, 112 and associated escape space is part of the female element 18ff. Of course, according to an aspect regarded as independently inventive and to be considered as encompassed by the scope of the present invention, this assignment can be provided analogously or vice versa, i.e. in an analogous independently inventive embodiment, the groove 37 provided for retention can also be arranged in the female element 18ff, and the system of retention-providing bead 38 with associated intermediate or partial body 36, 112 and associated escape space can be part of the male element 14, 14', 14".As mentioned, the connection system provided by the structure of the telescopic crown 30' offers enormous advantages, since the only partial or partial provision of the partial bodies 112, which are provided as resilient locking or snap-on elements, allows them to be limited in the circumferential direction to a partial segment or a partial area in which there is sufficient space for attaching such elements, particularly with regard to the oral or dentition situation. According to one aspect of the invention, the finding is taken into account that for the preparation and attachment of dental prostheses, there is usually comparatively good space available in a direction "along the dentition", i.e., in a mesio-distal orientation, whereas comparatively little space is available in a direction "transverse to the dentition", i.e., in a buccal-palatal or buccal-lingual orientation.According to an aspect of the invention considered to be independently inventive, the locking elements 124 and the elements forming them are thus limited primarily or almost entirely in the mesio-distal direction, relative to the intended orientation of the telescopic crown 30'. Accordingly, according to an aspect considered to be independently inventive, the partial bodies 112 and, accordingly, the pockets 118 of the outer cap 34' assigned thereto, as seen in plan view, are arranged on the circumference in an angular range relative to the mesio-distal direction of less than 75°, preferably less than 60°, particularly preferably less than 45°, and are limited to this.These angles refer to the angle of the limiting outer straight line to the main direction determined by the mesio-distal alignment; accordingly, the complete opening angle, also referred to as the "effective locking range", is limited according to one aspect of the invention to 150°, preferably at most 120°, particularly preferably at most 90°.

[0178] As mentioned, the groove 37 provided in the male element 14" could, in contrast, be completely circumferential. Particularly in the case of restorations on implants or abutments, this groove 37 can be completely circumferential, since the design of the male elements 14 on implants or abutments is preferably rotationally symmetrical and can be made smaller than on a natural tooth anyway. In the case of restorations on natural teeth, the already prepared tooth has a dimension that cannot be used for retention. In such a case, it is extremely advantageous if the wall thickness used for the male cap does not have to be additionally thickened in the buccal, palatal, and lingual directions due to the retention groove or another retention element. However, FIGS. 27-29 show an embodiment in which, in an independently inventive embodiment, the male element 14" is designed in the same way according to these principles.The male element 14" thus forms a primary crown 12 considered to be inventive. The crown body 130 forming this, which can in principle also be used independently of the above-described embodiments and is considered to be independently inventive, is shown in FIG. 30 in various views and in particular in FIG. 130d in a view "from below" and in FIG. 30e in cross-section. Corresponding to the design and positioning of the above-described partial bodies 112 and the further components of the respective locking element 124, the crown body 130 is also provided with an undercut, selective in the circumferential direction, only partially formed, intended to produce retention. This undercut is formed by a number of grooves or notches 132.In principle, such a notch 132, extending in cross-section in the circumferential direction only over a partial segment of the circumference, could be sufficient; however, in the exemplary embodiment and according to one aspect of the invention, two such notches 132 are provided. Corresponding to the above-described configuration of the outer cap 34', the crown body 130, preferably provided as the primary crown 12 or male element 14", is thus also provided, in this configuration considered to be independently inventive, for geometry-related retention primarily or solely in a mesio-distal orientation.

[0179] With this embodiment, which is regarded as independently inventive, the crown bodies 130 provided for arrangement as caps on the stumps or abutments of the respective teeth 6 can thus be designed with comparatively thin walls in the buccal-palatal or buccal-lingual plane. Rather, the crown body 130 has, in each case in the front and rear region, viewed in the mesio-distal direction, a notched groove segment formed by the respective notch 132. According to one aspect of the invention, this is limited in the azimuthal direction to a segment which is only provided in the front and rear region of the tooth 6, where there is sufficient space to accommodate the provided snap connection. In this embodiment, according to one aspect of the invention, the notch 132 orThe undercut, viewed in plan view, is thus limited to a partial segment of the contact surface 33 provided for alignment in the mesio-distal direction in the patient's mouth, as can be seen in particular from the illustration in FIG. 30e. In particular, according to an aspect considered to be independently inventive, the notches 132, viewed in cross-section, are arranged on the circumference in an angular range relative to the mesio-distal direction indicated by the axis 134 of less than 60°, preferably less than 45°, particularly preferably less than 30°, and are limited to this. These angles relate to the angle of the limiting outer straight line to the main direction given by the mesio-distal alignment; accordingly, the complete opening angle α, also referred to as the "effective locking range", is limited according to one aspect of the invention to 120°, preferably at most 90°, particularly preferably at most 60°.

[0180] According to one aspect of the invention, the notches 132 can be arranged directly opposite one another in the azimuthal direction on the outer circumference of the contact surface 33 of the crown body 130, as shown in the example of FIG. 30e. In this case, they are thus offset from one another by an azimuthal angle of 180°. Alternatively, however, a different relative orientation to one another can also be provided, particularly with regard to the underlying dental situation corresponding to the dental arch in the patient's mouth. In particular, this offset angle can be 120° or even 90°.

[0181] The design of the crown body 130 intended as a male cap, which is considered to be independently inventive, comprises, among other things, a region arranged above the crown equator or above the preparation margin / lower crown edge, which tapers conically towards the occlusal end 136 and is interrupted in the mesial and distal directions by one of the notches 132 forming a depression. This depression or shaped recess serves in the male cap 14 as a retention element for the female element 18 as a whole. This is where the cams 116 of the inner cap 32 engage the grooves 132 of the male 14. Since the space available in a prosthesis is very limited in the buccal-palatal or buccal-lingual direction, but in contrast there is sufficient space in the mesio-distal plane, according to one aspect of the invention both the projections formed by the cams 116 or the bead 38, which are provided in the matrix cap orin the respective matrix element 18ff as well as the corresponding retention recesses formed by the respective notch 132 in the male cap or the crown body 130 according to this aspect of the invention are arranged primarily or even exclusively in the region of the mesio-distal plane or direction.

[0182] A further fundamental concept of the present invention is thus seen in providing a mechanism for a locking or snap connection for fastening a matrix element 18, 18', 18", 18'", 18"", 18 on a patrix element 14, 14', 14" or a crown for abutments or natural teeth of a telescopic crown 30, 30', in which the locking or snap mechanism between the matrix and patrix elements is not designed to be fully circumferential on or in them. Particularly with regard to the ever-increasing demands of patients regarding the aesthetics of their prosthetic restorations, it is considered particularly important to design the connections of removable prosthetic concepts to be as small and as space-saving as possible.In the exemplary embodiments of the present invention, the concept of conical telescopes is particularly motivated, as these are particularly well suited for transmitting masticatory forces to the underlying implants and / or the underlying remaining dentition. These can be implemented in an extremely space-saving manner, also in combination with a positioning compensator and supplemented by a number of locking or snapping elements in the mesio-distal direction. Thus, in one aspect, the invention provides a combination of optimized force transmission and an optimized locking or snapping mechanism.

[0183] Mucosa-supported complete dentures usually provide relatively good retention in the upper jaw, but a rather unsatisfactory hold in the usually atrophied lower jaw. If a patient cannot afford an implantological solution for the lower and upper jaw due to the costs, but still wants to improve the adhesion of the lower jaw prosthesis, a high force transmission of the lower jaw prosthesis will not be necessary. Since there is a mucosa-supported prosthesis in the opposing jaw (usually the upper jaw), the chewing force to be transmitted will be relatively low. For this reason, it is sufficient if the matrix-patrice system for the opposing jaw, which is usually treated with implants, focuses on the locking or snap-in mechanism and force transmission is not the main focus, and is solved using other non-conical concepts.According to an aspect considered to be independently inventive and to be encompassed by the scope of the present invention, a matrix-patrice system is characterized in that the locking or snapping mechanism is interrupted relative to the circumference of the matrix-patrice system and has a number of locking or snapping elements that are oriented mesially and / or distally. Accordingly, the locking or snapping elements are arranged on the circumference of the matrix-patrice system in a plan view at an angular range relative to the mesio-distal direction of less than 75°, preferably less than 60°, particularly preferably less than 45°, and are limited to this.These angles refer to the angle of the limiting outer straight line to the main direction determined by the mesio-distal alignment; accordingly, the complete opening angle, also referred to as the "effective locking range", is limited according to one aspect of the invention to 150°, preferably at most 120°, particularly preferably at most 90°.

[0184] With regard to the design of the cap, it is further intended to keep wear and tear caused by the frequently repeated insertion and removal of the prosthesis 1 as low as possible. Furthermore, the retention elements should purely perform the function of holding the prosthesis on the male caps and not serve to transmit force from the female caps to the male cap during chewing. The chewing force should preferably be transmitted exclusively via the conical surfaces and the roof surface 138 of the male cap. Furthermore, when the prosthesis 1 is inserted, there should preferably be no or hardly any cavity between the female element 18 and the male element 14 in which food residues could accumulate. Germs and other contaminants often accumulate in such cavities, which in turn are difficult to clean or remove. Furthermore, they can also be the starting point for inflammatory processes.Accordingly, the shape of the crown body and its outer surface is suitably selected and, in particular, suitably adapted to the corresponding inner contour of the matrix element 18ff. In particular, for these reasons and to facilitate production using appropriate milling cutters, in one aspect of the invention, the conical surfaces of the crown body 130 are aligned collinearly with one another in the occlusal direction and in the apical direction on both sides of the retention recesses in the male cap, so that they exhibit as little offset as possible. Any production-related offset of the lateral surface of the crown body 130 in the region above the respective notch 132 on the one hand and below the respective notch 132 on the other hand should, according to one aspect of the invention, be kept less than 0.25 mm and preferably less than 0.1 mm and particularly preferably less than 0.05 mm.Any resulting varying difference in the cone angle of the lateral surface between these two regions should also be less than 5°, preferably less than 2.5°, and particularly preferably less than 1°. Excessively large a change in the angle or excessive offset between the conical surfaces above and below the retention recesses or notches 132 could have negative effects on the uniform force transmission and pose a risk of cavities between the matrix cap and the patrice cap. Another feature considered important according to one aspect of the invention for the use of the overall system as a force transmission and locking element is the design of the conical surfaces and radii or transition radii in the region of the retention elements, particularly with regard to the contour of the notch 132. FIG. 30f shows the lateral surface of the crown body 130 in a central longitudinal section.The notch 132 is formed by the main radius r3, which is important for retention and which, in the edge regions of the notch 132, transitions via the additional transition radii r2 and r4 into the conical lateral surfaces 139a, 139b above and below the notch 132. Also shown are the radius r1, with which the upper partial surface 139a transitions into the roof surface 138, and the radius r5, with which the conical lateral surface A of the crown body 130 transitions into the lower basal part B. The depth of the notch 132 is designated C.

[0185] To minimize wear and protect the soft tissue, one aspect of the invention can provide for the transitions between surfaces A, B and radii r1 - r5 and between adjacent radii r1 - r5 to be tangential to one another, as otherwise there could be a risk of sharp corners, which would increase wear and promote soft tissue irritation. In particular, the transitions between the occlusal conical surface A and radius r2 and in the apical direction to the main radius r3 are preferably kept tangential. Furthermore, to minimize wear, the transition radius r2 should be at most as large as the main radius r3. A ratio of the radii r2 to r3 between 3:1 and 1:10 is considered particularly favorable and therefore preferred. A ratio between 2:1 and 1:6 is preferred, and a ratio between 1:1 and 1:4 is particularly preferred.

[0186] Furthermore, the depth C of the notch 132 provided as a retention recess is also considered an important parameter. Firstly, there should be sufficient space for the intended retention function; however, even in the mesio-distal plane, there is not unlimited space in the prosthesis. In addition, the elastic deformation of the materials of the inner cap 32 is also limited. For the depth C of the retention recess in Figure 30f, a depth between 0.1 mm and 1.0 mm is advantageous. Preferably, the depth C is between 0.1 mm and 0.5 mm, and particularly preferably between 0.15 and 0.3 mm.

[0187] A fundamental concept of the present invention with regard to the design of the primary crown 12, which is provided in particular as a male element 14 and is considered to be independently inventive, is seen in the provision of a mechanism for a locking or snap-in connection for attaching the female element 18ff in interaction with the associated female element 18ff, in which mechanism the comparatively soft or deformable intermediate body 36 or partial body 112 cooperates with an escape space so that the cam 116, which cooperates with the respective notch 132 forming the groove segment 114 to provide the retention, can resiliently escape if necessary in order to enable snapping or engaging.The escape space provided for this purpose can be provided by a sufficiently voluminous intermediate body 36 or by the pockets 118, wherein the pockets 118 can be filled completely, partially, or not at all with the material of the partial body 112 and can optionally also enclose additional air cushions. For this purpose, in the above and also in the following examples, the notch is arranged in the crown body 130, and the system of retention-providing cam 116 with associated intermediate or partial body 36, 112 and associated escape space is part of the matrix element 18ff. Of course, according to an aspect considered to be independently inventive and to be considered to be encompassed by the scope of the present invention, this assignment can be provided analogously or vice versa, i.e.In an analogous independently inventive embodiment, the groove or notch 132 provided for retention can also be arranged in the matrix element 18ff, and the system of retention-providing cam 116 with any associated intermediate or partial body 36, 112 and any associated escape space can be part of the crown body 130. A crown body 130 designed in this way is also considered independently inventive.

[0188] An alternative embodiment of a telescopic crown 140, which is also considered to be independently inventive and is intended for attachment to an inserted post part 74 of a dental implant 72, is shown in FIGS. 31 to 34. In this case, too, the male element 14' is formed by the abutment 76' which is correspondingly shaped in its head region and made in one piece with the connecting screw 78. FIG. 31 shows the telescopic crown 140 in an exploded view in a side view (FIG. 31a), with the same viewing direction in longitudinal section (FIG. 31b), in a further side view rotated by 90° about the longitudinal axis compared to FIG. 31a, and also for this viewing direction in longitudinal section (FIG. 31d). FIG. 32 shows the female element 18 of this telescopic crown 140 in the view shown in FIG. 31a. FIG. 33, however, shows the telescopic crown 140 in a partially assembled state in a side view (FIG. 33a) and in a longitudinal section (FIG. 33b), and FIG.Fig. 34 shows the telescopic crown 140 completely mounted on the dental implant 72 in a lateral view (FIG. 34a), with the same viewing direction in longitudinal section (FIG. 34b), in a further lateral view rotated by 90° about the longitudinal axis compared to Fig. 34a (FIG. 34c) and also for this viewing direction in longitudinal section (FIG. 34d).

[0189] According to one aspect of the invention, the matrix element 18 of this telescopic crown 140 is also designed according to the concept already described above for the design of the intermediate body 36, formed from only two partial bodies 112, wherein the two partial bodies 112, viewed in the azimuthal direction, also extend only over a partial segment of the circumference of the contact surface 33. The above-described explanations and aspects regarding the matrix element 18"" also apply here, including the mentioned advantages, to the matrix element 18. It is particularly worth mentioning here that, due to the aforementioned design of the intermediate body 36, the inner cap 32 also bears directly against the inner surface of the outer cap 34 over large parts.

[0190] Corresponding to the partial bodies 112, in this exemplary embodiment, according to one aspect of the invention, the inner cap 32, instead of a completely circumferential bead 38, is also provided with locally limited cams 116, each pointing inward at a corresponding position, each of which is assigned to one of the partial bodies 112. The outer cap 34 of the telescopic crown 140 is also provided with a corresponding pocket 118 for each provided partial body 112 to form the above-described snap or locking elements 124. This pocket is visible on the outside in the form of a bulge and, as can be clearly seen from the cross-sectional view in FIG. 32, extends in the azimuthal or circumferential direction only over a partial segment of the outer cap 34.Analogous to the example described above, in this embodiment, which is considered to be independently inventive, additional retention between the matrix element is achieved by the pockets 118. and the prosthetic body 2. The retention between the male element 14' and the inner cap 32, however, is achieved as described above by the respective snap or locking connection by means of the resilient locking element 124 formed by the cams 116 in conjunction with the groove 37 in the male element 14'. In this exemplary embodiment, no position compensation can take place during insertion in the patient's mouth, since there is no circumferential intermediate body 36. This variant, which is considered to be independently inventive, represents the thinnest possible design of a telescopic restoration including a locking mechanism. It can be implemented on implants or abutments, as shown here in the exemplary embodiment, but can of course also be used for restorations on patient caps on natural teeth.

[0191] Another alternative embodiment of a telescopic crown 150, also considered to be independently inventive, intended for attachment to an inserted post part 74 of a dental implant 72, is shown in FIGS. 35 to 38. This embodiment largely corresponds to the telescopic crown 140 described above, wherein the matrix element 152, which is otherwise largely identical to the matrix element 18, has a "conventional" intermediate body 36 that completely encloses the inner cap 32 in cross-section at its outer circumference. Instead of the sections 112, this intermediate body 36 now comprises externally formed bead segments 154 that engage in the pockets 118 when the intermediate body 36 is inserted into the outer cap 34.

[0192] In all of the embodiments described above, according to one aspect of the invention, it is sought and intended to keep the wall thickness of the inner cap 32 as thin as possible. This provides, on the one hand, a sufficiently high thermal permeability for heating the intermediate body when the intermediate body 36 is designed as a thermoplastic element, and, on the other hand, it promotes the desired small overall diameter and thus a small space requirement for the entire die-cap system. However, the thinner the inner cap 32 is made, the more the longevity of the intended locking function depends on the reliable connection between the intermediate body 36 and the inner cap 32. Should this connection become loose, there is a risk that the inner cap 32 will detach from the intermediate body 36 when the die element 18, 152 is separated from the male element 14, and the die element 18, 152 will thus be destroyed.

[0193] The avoidance of such destruction can be achieved in a variant regarded as independently inventive by either forming a retention for the intermediate body 36 in the inner cap 32 in the area of ​​engagement with the male element 14, where the forces are actually transmitted, and / or by retention elements engaging into the intermediate body 36 from the inner cap 32. These retentions can be circumferential or only present in partial areas, particularly in the areas in which engagement of the inner cap of the female cap with the male element takes place. An inner cap 160 designed in this way, which can be used for any of the variants described above and modified according to this aspect, is shown in FIG. 39. The inner cap 160, which is fundamentally and according to the considerations described above is preferably made of PEEK or a comparable material, is in the version shown in FIG.The variant shown in FIG. 39a is provided with an inwardly directed retention element 164 designed in the manner of a bulge 162, which can interact with a suitably engaging bead or thickened portion attached to the inside of the intermediate body 36. In the variant shown in FIG. 39b, however, a retention element 166 is molded onto the outside of the inner cap 160. When the matrix element 168 is mounted, as shown in the longitudinal section in FIG. 40, this retention element engages in a suitably shaped undercut in the intermediate body 36.

[0194] The following describes a further extension of a matrix-patrice system that is considered to be independently inventive. In this case, locking caps are inserted into the prosthesis (partial or full denture) or are fixed, glued, or cemented therein, into which the matrix, advantageously the outer cap of the matrix, can be removably inserted. The decisive factor here is, of course, that the holding force for the matrix or outer cap in the denture cap is significantly greater than the holding force between the matrix and the patrice. The reason for this is that if the matrix is ​​worn or otherwise destroyed, it can simply be replaced without having to grind the old matrix or matrices out of the denture and then having to glue the new matrix or matrices back into the denture. For this purpose, the outer region of the outer cap, in conjunction with the denture cap, provides a number of mechanical retention mechanisms.Locking mechanisms are available. It is possible, and it would also be sensible, if the old matrices could only be removed with the aid of a special tool to prevent them from being accidentally loosened by the patient. In order to make these retentions or locking mechanisms as space-saving as possible, they are also advantageously only attached in the mesial and / or distal direction. In a particularly advantageous embodiment of the invention, which is regarded as an independent one, the denture caps have additional wings in the mesial and / or distal direction. Although these do not replace a perfect tertiary framework, they significantly reduce the risk of fracture in dentures without a tertiary framework. The assumption here is that the actual patrix in the plastic denture weakens it at this point. Furthermore, the denture is subjected to bending loads around the bridge abutments, in our situation around the matrices, similar to a bridge.The wings in the mesial and / or distal direction can introduce this bending into the prosthesis much better and in a more distributed manner and thus significantly reduce the risk of fracture of the prosthesis.

[0195] A method for producing a dental prosthesis 1, which is intended for removable fixation to a number of crowned teeth 6 or, in particular, dental implants in the mouth of a patient by means of fastening systems 10 of the type described, is also considered to be independently inventive. According to this aspect of the invention, intraoral data reflecting the actual dentition situation in the patient's mouth can first be recorded and made available for further digital processing. Based on this data, according to one aspect of the invention, a patrice element 14 that is considered particularly favorable for the determined dentition situation is selected from a number of basic patrice element types stored in a component library, preferably in a CAD system.Especially in the application of the method to the production of a prosthesis for attachment to a dental implant, which is considered particularly advantageous, the precise position and orientation of the inserted dental implant can be recorded in a manner considered to be independently inventive when the intraoral data for the dentition situation is initially acquired. Based on this data and taking into account the selected male element, the abutment intended for attachment to the implant can be suitably planned and manufactured. In particular, the orientation and positioning of the abutment can be optimized with regard to the dentition situation, and if necessary, the basic shape of the abutment can be suitably specified.

[0196] When selecting a suitable basic type of male element, one or more of the following criteria are taken into account in particular according to aspects of the invention:

[0197] - the male parts should be able to be attached in such a way that their respective longitudinal axes are aligned largely parallel to one another after being attached in the oral cavity, whereby for the respective male part the angle between its longitudinal axis and the parallel alignment should be at most 15°, preferably at most 10° and particularly preferably at most 6°.

[0198] - the required removal of tooth substance should be as low as possible for each individual male body and / or for the ensemble of all male bodies

[0199] - the or each male body should be as small as possible. In this production, in particular for use with an inserted dental implant, the following steps, each individually or in suitable combination with each other, may be considered inventive:

[0200] Before the final prosthesis or prosthetics are developed, a male design for later use is preferably defined in CAD. The selection can be made based on male designs already available or stored in a corresponding CAD library, for which suitable females are available.

[0201] The male elements 14 are aligned during the planning process, i.e. preferably during the design in CAD, for an insertion direction of the finished prosthesis or prosthetics optimized from the data of the oral situation (remaining dentition, mucous membrane, opposing jaw) recorded via the intraoral scanner and are aligned with the ground tooth stump or, in particular, with the recorded situation of the inserted implant.

[0202] Based on the target position for the male element 14 specified in this way or by other means, the abutment can be planned and subsequently fabricated, taking into account the location and geometry data of the inserted implant. If necessary, a basic abutment type (e.g., an angled abutment) can be selected, which can then be further modified based on the determined data for the dentition situation.

[0203] Based on the planning data for the male element 14 and, if applicable, the abutment, the cap to be manufactured is planned, which forms a matrix relative to the tooth stump or abutment and represents a male relative to the prosthesis or prosthetics, which plunges into the matrices 18 of the detachable connection to the prosthesis or prosthetics.

[0204] For the dental laboratory procedure, three variants are described below, each of which is considered to be independently inventive.

[0205] 1. Classic procedure with the already manufactured male cap:

[0206] After the patrix caps are fabricated, they are temporarily attached to the tooth stumps of the physical master model (plaster model, printed plastic model, etc.). The matrix elements 18 are then attached to the primary crowns 12. The prosthesis is then planned, designed, and fabricated on these. Finally, the fabricated prosthesis or prosthetic is bonded or cemented, preferably to the master model, to the matrix elements 18.

[0207] 2. Procedure I with primary crown analogues integrated into the master model:

[0208] In a second variant, the corresponding prefabricated primary crowns are integrated into a printed master model, or the primary crowns are printed directly with the master model. The matrix elements 18 are then attached to the primary crowns 12. The prosthesis is then planned, designed, and fabricated on these. Finally, the fabricated prosthesis / prosthetic is bonded / cemented, preferably to the master model, using the matrix elements 18.

[0209] 3. Procedure II with primary crown analogues integrated into the master model:

[0210] In the third variant, the primary crowns are fabricated and bonded or cemented before the master model is created. Here, after the tooth stumps have been prepared, the primary crowns are fabricated directly by the dentist ("chairside") or in a nearby dental laboratory and bonded or cemented in the same appointment. An intraoral scan or conventional impression can then be taken, preferably with appropriate impression copings on the primary crowns. A master model (plaster model, printed plastic model, etc.) with integrated primary crown analogs can then be fabricated. The matrix elements 18 are then attached to the primary crowns 12. The prosthesis is then planned, designed, and fabricated on these. Finally, the fabricated prosthesis / prosthetic is bonded / cemented, preferably to the master model, using the matrix elements 18.

[0211] The processes can also be combined, at least partially.

[0212] According to further aspects of the invention, the complete dental prosthetic system can be digitally planned based on the acquired intraoral data. In particular, a physical 3D model of the actual dentition situation in the patient's mouth can preferably be created based on the acquired intraoral data. The selected male parts are temporarily attached to this model in their target position determined by the digital planning, and the removable dentures are fabricated based on the resulting assembly. Advantageously, and according to one aspect of the invention, the 3D model and / or the removable dentures are fabricated using 3D printing.

[0213] According to further aspects of the invention, the design and planning of the male elements on implants can be carried out in three possible variants. These are described as follows.

[0214] 1. The position of the implants was recorded via an intraoral scan or a conventional impression and can now be used by the software together with the surrounding position data of the oral situation. The software selects from a library of male part variants those which can be considered the most favorable in terms of insertion direction and space requirements for the planned prosthesis. The male part is designed to be as small as necessary but as large as possible. The reason for this is that the longevity of the matrix-male part system also depends on the applied chewing forces. The larger the contact area 31 between the matrix inner cap 38 and the male part 14, the lower the surface pressure during chewing. This means that the male part is as large as possible but as small as necessary in relation to the aesthetics individually required by the patient.This also means that the size selection is influenced by the positioning of the implants. In the next step, the software designs a CAD / CAM abutment, merging the surfaces of the implant connection with the male surface in such a way that the anatomical relationships of the hard and soft tissue, especially the gingival contour, are also taken into account. The CAD / CAM abutment is then manufactured conventionally from titanium, or an abutment with a stump in the occlusal direction, onto which a corresponding ceramic male cap can be fixed.

[0215] 2. The position of the implants was recorded via an intraoral scan or a conventional impression and can now be used by the software together with the surrounding position data of the mouth situation. The software now plans corresponding titanium base abutments with a prefabricated end that fits the implant and a connection that is also prefabricated in the occlusal direction into the scan. The software calculates the most optimal positioning of the possible male elements in relation to the insertion direction. Two further variants are now available to choose from. a. The software selects the most optimal variant from a library of male variants in terms of the insertion direction and the space required for the prosthesis to be planned. The male is designed to be as small as necessary but as large as possible.The reason for this is that the longevity of the matrix-matrix system also depends on the applied chewing forces. The larger the contact surface 31 between the matrix inner cap 38 and the patrix 14, the lower the surface pressure during chewing. This means that the patrix is ​​as large as possible but as small as possible in relation to the aesthetics individually required by the patient. It also follows that the selection of the size is influenced by the positioning of the implants. In a further step, the pure surface of the patrix element is adapted to the contact surface of the titanium base abutment and the two are fused together. In a subsequent step, the adapted patrix element is manufactured either from a metal, preferably from titanium or a titanium alloy, or from a dental ceramic and bonded to the titanium base abutments. b.The software generally selects the smallest possible male element, which is usually also available as a standard abutment. In a next step, the pure surface of the male element is adapted to the contact surface of the titanium base abutment, and the two are fused together. In a subsequent step, the adapted male element is manufactured either from a metal, preferably titanium or a titanium alloy, or from a dental ceramic, and bonded to the titanium base abutments.

[0216] 3. The position of the implants was recorded via an intraoral scan or a conventional impression and can now be used by the software together with the surrounding position data of the oral situation. The software then plans the smallest possible male configuration and determines the three-dimensional orientation of the males for an optimized insertion direction of the subsequent prosthesis. In the next step, the software designs a CAD / CAM abutment, whereby the surfaces of the implant connection are fused with the male surface in such a way that the anatomical relationships of the hard and soft tissue, especially the gingival line, are taken into account. The CAD / CAM abutment is then conventionally manufactured from titanium. List of reference symbols

[0217] 1 dentures

[0218] 2 prosthetic bodies

[0219] 4 Upper jaw

[0220] 6 tooth

[0221] 10 Fastening system

[0222] 12 Primary crown

[0223] 14, 14', 14" male element

[0224] 16 contact pins

[0225] 18, 18', 18",

[0226] 18'", 18"",

[0227] 18 matrix element

[0228] 20 Arrow

[0229] 30, 30' telescopic crown

[0230] 31 , 33 contact surface

[0231] 32 inner cap

[0232] 34, 34' outer cap

[0233] 36 intermediate bodies

[0234] 37 grooves

[0235] 38 inner bead

[0236] 39 End

[0237] 40 bead

[0238] 42 mounting groove

[0239] 44, 46 Ensemble

[0240] 48 Fixing edge

[0241] 50 mounting ring

[0242] 52 beaded edge

[0243] 54 Lid area

[0244] 60 heater

[0245] 62 contact plugs

[0246] 64 heating element

[0247] 66 handle element

[0248] 68 temperature sensors

[0249] 70 cable connection

[0250] 72 Dental implant Post part Indexing Abutment Connecting screw Basal area Contact surface Screw channel Connecting piece Screw seat Platform surface Sleeve Screw head Cover surface Access opening Outer bead Groove Retention element Turn-over rim Partial body Groove segment Cam Pocket Locking system Locking element Crown body Notch Axis End

[0251] Roof surfacea, 139b Conical partial surfaces, 150 Telescopic crown Matrix element Bead segment Inner cap Bulge, 166 Retention element 168 Matrix element a Opening angle r1, r2, r3, r4, r5 Radius

[0252] A lateral surface

[0253] B Basal area

[0254] C Depth of the notch

Claims

Claims 1. Removable dental prosthesis (1) with a prosthesis body (2) and with a number of matrix elements (18, 168), each of which can be plugged onto an associated male element (14, 14', 14"), in particular arranged on a tooth (6) or an inserted dental implant (72) in the oral cavity of a patient, wherein the or each matrix element (18, 168) has an inner cap (32, 160) which forms a contact surface (31) for the associated male element (14, 14', 14") and can be plugged onto the latter, which inner cap is made of a comparatively hard plastic in the region of the contact surface (31) and is fastened to the prosthesis body (2) via an intermediate body (36) made of a comparatively softer plastic.

2. Telescopic crown (30) for fastening a removable dental prosthesis (2), in particular according to claim 1, to a tooth (6) or an inserted dental implant (72) in the oral cavity of a patient, with a male element (14, 14', 14") which can be fastened to the tooth (6) or the dental implant (72) and with a female element (18, 168) which can be plugged onto the male element and attached to the dental prosthesis (2), wherein the female element (18, 168) is designed in several parts and comprises an inner cap (32) which forms a contact surface (31) for the associated male element (14, 14', 14") and which can be plugged onto the latter, and an outer cap (34) which can be attached to the dental prosthesis (2), wherein the inner cap (32) is made of a comparatively hard plastic in the region of the contact surface (31), and wherein An intermediate body (36) made of a comparatively softer plastic is arranged in the space between the inner and outer caps (32, 34) and connects them to one another.

3. Dental prosthesis or telescopic crown according to claim 1 or 2, wherein the intermediate body (36) is formed from an ethylene-vinyl acetate copolymer, polyethylene, polypropylene, a polyolefin or a polyamide.

4. Dental prosthesis or telescopic crown according to one of the preceding claims, wherein the intermediate body (36) has a tensile modulus of elasticity of less than 100 MPa.

5. Dental prosthesis or telescopic crown according to one of the preceding claims, wherein the part of the inner cap (32) of the matrix element (18, 168) forming the contact surface (31) is formed from PEEK, PPS, PPSU or PSU.

6. Dental prosthesis or telescopic crown according to one of the preceding claims, wherein the part of the inner cap (32) of the matrix element (18, 168) forming the contact surface (31) has a tensile modulus of elasticity of at least 1000 MPa, preferably of at least 2000 MPa.

7. Dental prosthesis or telescopic crown according to one of the preceding claims, wherein the part of the inner cap (32) of the matrix element (18, 168) forming the contact surface (31) has a tensile modulus of elasticity of at least ten times, preferably at least 25 times MPa, most preferably at least 50 times, the tensile modulus of elasticity of the intermediate body.

8. Dental prosthesis or telescopic crown according to one of the preceding claims, wherein the intermediate body (36) of the or each matrix element (18, 168) is formed from a thermoplastic material, preferably from a thermoplastic elastomer.

9. Dental prosthesis or telescopic crown according to claim 8, wherein the material of the intermediate body (36) of the or each matrix element (18, 168) has a solidification temperature of at least 80°C, preferably more than 135°C.

10. Dental prosthesis or telescopic crown according to one of the preceding claims, wherein the intermediate body (36) of the or each matrix element (18, 168) has an average thickness of at least 100 pm, preferably at least 250 pm, particularly preferably at least 500 pm.

11. Male element (14, 14', 14") for use with a dental prosthesis (2) or in a telescopic crown according to one of the preceding claims, with a contact surface corresponding to the contact surface of the respective female element (18) which has a groove or undercut.

12. Male element (14, 14', 14") according to claim 11, which is designed as a male body for attachment to a tooth (6).

13. Male element (14, 14', 14”) according to claim 11, which is formed on a mounting part or abutment of a dental implant.

14. Male element (14, 14', 14") according to one of claims 11 to 13, the contact surface of which has a cross-section tapering towards the free, occlusal end, preferably in the manner of a conical configuration.

15. Male element (14, 14', 14") according to one of claims 11 to 14, which has a non-circular, elongated cross-section when viewed in plan.

16. Male element (14, 14', 14") according to one of claims 11 to 15, the groove or undercut of which, as seen in plan view, is limited to a partial segment of the contact surface intended for alignment in the mesio-distal direction in the patient's mouth.

17. Male element (14, 14', 14”) according to one of claims 11 to 16, which is made of titanium or a dental ceramic.

18. Male element (14, 14', 14") according to one of claims 11 to 13, which is provided with a scanner marking element at its free, occlusal end.

19. Crown body (130) for attachment to a tooth stump or a dental implant in the mouth of a patient, having a contact surface (33) on which at least one retention element is arranged, wherein all of these retention elements are positioned in an angular range of at most 60°, relative to the mesio- and / or distal main direction on the contact surface (33).

20. Crown body (130) according to claim 19, wherein the respective retention element is designed as a notched groove (132).

21. Use of a crown body (130) according to claim 19 or 20 as a male element according to one of the preceding claims.

22. Dental prosthetic system with a removable dental prosthesis (1) according to one of the preceding claims, and with one of the number of male elements (14, 14', 14") each intended for attachment to a tooth (6) or implant (72) in the mouth of a patient according to one of claims 11 to 18.

23. Dental prosthetic system according to claim 22, wherein at least one of the matrix elements (18) associated with the dental prosthesis (1) is provided with a locking element (124) that can be inserted into the groove or undercut (37) of the associated patrix element (14, 14', 14").

24. Dental prosthetic system according to claim 23, wherein the or each locking element (124) is resiliently mounted.

25. Dental prosthetic system according to one of claims 22 to 24, wherein the or each locking element (124) is formed by a shaping of the inner cap (32) of the respective matrix element (18, 168).

26. A method for producing a dental prosthetic system with a removable dental prosthesis (1) according to one of the preceding claims, which is provided for removable fixation to a number of crowned teeth (6) or in particular also dental implants (72) in the mouth of a patient by means of a number of male bodies each forming a male element (14), in which intraoral data reflecting the actual dentition situation in the oral cavity of the patient are recorded and made available for digitalized further processing, wherein on the basis of this data, preferably in a CAD system, a suitable male element (14) is selected for each intended male element (14) from a number of basic male element types stored in a component library.

27. The method according to claim 26, wherein the acquisition of the intraoral data occurs after a preceding preparation step.

28. Method according to claim 26 or 27, wherein the selection of a male body considered suitable and / or the combination with the other male bodies is carried out on the basis of one or more of the following criteria: - the male bodies should be able to be mounted in such a way that their respective longitudinal axes after placement in the oral cavity, are largely aligned parallel to each other, whereby for each male body the angle between its longitudinal axis and the parallel alignment should not exceed 15° - the required removal of tooth substance should be as low as possible for each individual male body and / or for the ensemble of all male bodies - the or each male body should be as small as possible.

29. Method according to one of claims 26 to 28, in which the complete dental prosthetic system is digitally planned based on the acquired intraoral data.

30. Method according to claim 29, in which a physical 3D model of the actual dentition situation in the patient's mouth is created on the basis of the acquired intraoral data, to which the selected male bodies are temporarily attached in their desired position determined by the digital planning, and the removable denture is manufactured on the basis of the resulting ensemble.

31. The method according to claim 30, wherein the 3D model and / or the removable dental prosthesis are manufactured by means of 3D printing.

32. Method according to one of claims 26 to 31 for producing a dental prosthesis (2) for attachment to a dental implant, in which the exact position and orientation of the inserted dental implant is recorded when the intraoral data for the dentition situation are recorded, wherein the abutment intended for attachment to the implant is suitably planned and manufactured on the basis of these data and taking into account the selected male element (14).

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