Method for producing a dental prosthesis using a support structure

Abstract

The invention relates to a method for producing a dental prosthesis, having the following steps: A) calculating a virtual fixing key with a surface as the negative of the outer shape of outer surfaces of the virtual prosthetic teeth; B) calculating a virtual support structure as a partial volume of the dental prosthesis with at least one one-piece tooth partial volume of a plurality of prosthetic teeth and spaced apart from outer surfaces of the prosthetic teeth; C) producing a fixing key (21) according to the model; D) inserting tooth shells (28) into the fixing key (21) in a manner matching the outer surfaces; E) producing the support structure (32) according to the model; F) applying and connecting the support structure (32) to the tooth shells (28) in the fixing key (21); and G) fastening or constructing a prosthesis base at or on the support structure (32). The invention also relates to a dental prosthesis and to a device for carrying out such a method.

Description

[0001] Method for manufacturing a dental prosthesis with a support structure 1

[0002] Description

[0003] The invention relates to a method for manufacturing a dental prosthesis, wherein the dental prosthesis comprises a denture base and several denture teeth, the denture base being made of a gum-colored plastic, the method being carried out using a virtual three-dimensional model of the dental prosthesis to be manufactured, and the virtual three-dimensional model comprising virtual denture teeth and a virtual denture base. The invention also relates to a dental prosthesis manufactured using such a method and to a device for carrying out the method.

[0004] Alongside traditional craftsmanship, digital manufacturing methods are gaining increasing importance in the dental field. For several years now, dental prostheses and other dental components, such as dentures, crowns, bridges, and bite splints, have been manufactured subtractively using CAD / CAM technologies in milling processes (CAM - Computer-Aided Manufacturing, CAD - Computer-Aided Design). CAD / CAM processes are also increasingly used in the fabrication and design of dental prostheses, including partial and complete dentures with a denture base that rests on the gingiva and supports or incorporates denture teeth.

[0005] In the digital design of prosthetic work, especially partial or complete dentures, the construction is divided into a "white" or tooth-colored tooth component (the denture teeth) and a gum-colored ("pink") denture base component (the denture base). Dental prostheses therefore consist of a gum-colored or pink base and tooth-colored components (denture teeth).

[0006] A CAD / CAM method for manufacturing a dental prosthesis is known from WO 91 / 07141 A1, in which a prosthesis base is milled from a plastic block based on an impression. There are methods, such as those known from DE 102009056752 A1 or WO 2013 / 124452 A1, in which a partial or complete dental prosthesis is digitally designed and produced using CAD / CAM technology. Patent DE 10304757 B4 discloses a method for manufacturing dental prostheses in which the teeth are virtually set up in a virtual model and a prosthesis base is manufactured based on this virtual model. EP 2742906 A1 discloses a method in which a dental arch is bonded to an impression material, the impression material being contained in a customized impression tray and containing an impression of the patient's oral cavity.The surface of the form containing the dental arch is digitized, and then a virtual model of the dental arch is computationally positioned and oriented as closely as possible within the virtual model of the denture base. German patent DE 10304757 B4 discloses a method for manufacturing dental prostheses in which the teeth are virtually set up in a virtual model, and a denture base is then manufactured based on this virtual model.

[0007] WO 2016 / 110392 A1 discloses a method for manufacturing a dental prosthesis in which a plastically deformable connecting element is inserted into tooth sockets of a denture base to allow manual correction of the alignment of the denture teeth in the denture base. EP 2571 451 B1 and EP 2666438 A2 disclose methods for manufacturing dental prostheses in which prefabricated denture teeth are embedded in wax in a holder and subsequently milled cervically using a CAM process. It is necessary to shorten the denture teeth basally (or cervically) to adapt the tooth height to the patient's jaw, i.e., to adjust the bite height of the dental prosthesis to the patient's needs. WO 2014 / 159436 A1 discloses a layered dental prosthesis with a reinforcement in the denture base that is cast into a basal cavity.In both additive and subtractive manufacturing, the connection between the denture base and denture teeth presents a significant challenge. This connection is typically achieved through bonding, but the quality of the transitions is prone to errors due to the use of too little or too much adhesive, as well as the correct positioning of the denture teeth during bonding. While available one-piece, two-color (gum-colored and tooth-colored) milling blanks or bodies offer excellent layer bonding, the aesthetics are always a compromise and therefore unsatisfactory due to the predetermined phase boundaries.

[0008] German patent DE 1020171174912 A1 discloses a method for producing a dental prosthesis in which a prosthesis base is milled in two steps and the prosthesis teeth are subsequently attached to the prosthesis base. Spacers are arranged in the tooth sockets to which the prosthesis teeth are attached, or on the basal surfaces of the prosthesis teeth themselves, to ensure a defined bonding gap when the prosthesis teeth are inserted into the tooth sockets. For this to work, the tooth sockets must be manufactured to precisely match the basal surfaces of the prosthesis teeth, and the tooth sockets, the basal surfaces of the prosthesis teeth, and the spacers must be manufactured with high precision. US patent 2022 / 0110730 A1 discloses a two-part dental prosthesis in which a dental arch portion and a gingival portion are attached to each other via suitable structures.From US 2022 / 0096217 A1, an array device and an array method are known in which denture teeth are attached to a denture plate, wherein an arrangement of the denture teeth is facilitated by a body with recesses matching the denture teeth and with positioning sections.

[0009] From EP 4389063 A1, a method for manufacturing a dental prosthesis is known in which prosthesis teeth are connected to a prosthesis base preform by filling a fluid polymerizable plastic into a space between the prosthesis teeth and the prosthesis base preform and subsequently subtractively machining the prosthesis base from the prosthesis base preform and the hardened plastic.

[0010] WO 2016 / 091 762 A1 discloses a method for manufacturing a dental prosthesis in which a template is produced that allows several prosthesis teeth to be attached to a denture base in the desired position and orientation relative to each other. The prosthesis teeth are shortened by basal grinding in a cervical area to achieve the desired occlusal height. Subsequently, the prosthesis teeth are fixed in tooth sockets created on the occlusal side of the denture base using a locking key, so that the parts can be assembled like a three-dimensional puzzle.

[0011] For functional, aesthetic, and manufacturing reasons, dental prostheses usually cannot be produced in a single manufacturing step, even in digital workflows. The gum-colored denture base and the tooth-colored part are often manufactured separately, and the final prosthesis is completed using joining techniques and bonding. The high degree of accuracy of fit between the contact surfaces of the parts to be joined is of particular importance. Additionally, prefabricated components (e.g., artificial denture teeth) may require prior adaptation (e.g., shortening). The following options generally exist for the production of digitally designed complete dentures according to current technology:

[0012] 1. Milling or printing the gum-colored base and bonding it to milled or printed artificial denture teeth, or alternatively to milled or printed tooth-colored segments. Disadvantages of this method can include: inaccuracies in manufacturing, time expenditure, aesthetic challenges due to excess adhesive or underfilling of marginal gaps, and limitations regarding the milling of cavities due to undercuts.

[0013] 2. Milling or printing the denture base and bonding individual denture teeth. These denture teeth may be pre-cut manually or automatically. A disadvantage of this method is the greater inaccuracy that arises when cutting the denture teeth. 3. Creating occlusal retention structures in a milling body, inserting tooth shapes, completing the milling body, and subsequently milling the complete denture geometry. A disadvantage of this method is the inaccuracy in joining the tooth shapes to the retention structures, as well as the complete coronal machining of the tooth shapes. The use of prefabricated denture teeth is not practical.

[0014] 4. Milling of prefabricated milling bodies with an integrated two-phase structure. The aim is to achieve a natural aesthetic through the skillful arrangement of the transitions. A potential disadvantage is the position of the transitions from gum-colored to tooth-colored, which always represents a compromise and is aesthetically unsatisfactory.

[0015] 5. Milling of pre-formed bodies into which prefabricated denture teeth are already integrated. With this method, primarily only the basal side of the denture is individually fabricated. A disadvantage of this approach is that compatibility with individual patient cases is extremely limited, and many variations of pre-formed bodies must be kept in stock.

[0016] 6. Layered construction of a prosthesis consisting of tooth-colored individual layers and a denture base through repeated milling and refilling of the milled cavities. Disadvantages of this method include significant material waste and considerable time expenditure. Furthermore, prefabricated denture teeth cannot be used with this technique.

[0017] 7. Production of basal tooth structures using milling technology, completion of the milling body with plastic, followed by milling of the complete prosthesis geometry. A potential disadvantage of this method is that a defined structure for the entire dental prosthetic work is only possible in a coherent workflow without options for using non-millable or prefabricated materials, such as prefabricated denture teeth.

[0018] Furthermore, a disadvantage of established methods is that precise fitting of prefabricated components is not possible. Many current methods also lack the ability to integrate retention elements, such as clasps, which are necessary for partial dentures.

[0019] Manually shortening prefabricated denture teeth presents the additional problem that the basal surface (the cervical area) of the denture teeth to be produced has an individual geometry. Before milling or printing the denture base, this geometry would need to be scanned and the corresponding counterpart for the denture base designed. This results in additional work. Established methods for manufacturing dental prostheses have various limitations, either regarding aesthetics or regarding the usable material combinations and the resulting material properties. The use of prefabricated teeth leads to highly aesthetic results, but the strength is limited due to the structure consisting of individual teeth and the PMMA denture base. Milled or printed segments allow for free design definition, but are not highly aesthetic in tooth-colored areas.This also applies to milled multilayer structures due to their predefined layers. Furthermore, printed and milled dental prostheses are currently clearly predefined with regard to the material structures they contain, e.g., composites or PMMA-based.

[0020] The object of the invention is to overcome at least one of the aforementioned disadvantages or at least one other disadvantage arising from the prior art. In particular, one object is to provide a method that enables the simple and rapid production of dental prostheses. The invention should utilize the most modern computer-controlled methods possible and make the broadest possible use of existing data and techniques. The dental prosthesis should preferably have the best possible aesthetic appearance and, at the same time, high mechanical strength.

[0021] The objects of the invention are solved by a method according to claim 1, a dental prosthesis according to claim 26 and a device for implementing the method according to claim 35. Preferred variants are claimed by dependent claims 2 to 25, 27 to 34 and 36.

[0022] At least one of the aforementioned tasks or a task arising from the prior art is therefore at least partially solved by a method for manufacturing a dental prosthesis, wherein the dental prosthesis has a denture base and several denture teeth, wherein the denture base has a gum-colored plastic, wherein the method is carried out using a virtual three-dimensional dental prosthesis model of the dental prosthesis to be manufactured, and wherein the virtual three-dimensional dental prosthesis model has virtual denture teeth and a virtual denture base, the method comprising the steps:

[0023] A) Computation of a virtual model of a fixing key, wherein a virtual first surface of the virtual model of the fixing key is computed as a first negative of the outer shape of outer surfaces of the virtual denture teeth, wherein the outer surfaces of the virtual denture teeth include vestibular surfaces and / or coronal surfaces of the virtual denture teeth;

[0024] B) Calculating a virtual model of a support structure with the stipulations that the support structure forms a partial volume of the virtual three-dimensional dental prosthesis model, that the partial volume of the support structure has at least one tooth partial volume of several of the virtual prosthesis teeth, that the at least one tooth partial volume is spaced away from the outer surfaces of the virtual prosthesis teeth or from partial areas of the outer surfaces of the virtual prosthesis teeth, and that each of the at least one tooth partial volume connects several of the virtual prosthesis teeth in one piece;

[0025] C) Manufacturing a locking key using a CAM process based on the data of the virtual model of the locking key calculated in step A);

[0026] D) Inserting tooth shells into the fixation key produced in step C), wherein the tooth shells have outer surfaces that correspond at least partially to the outer surfaces of the virtual denture teeth, wherein the outer surfaces of the tooth shells include vestibular surfaces and / or coronal surfaces of the tooth shells, wherein the outer surfaces of the tooth shells are placed against the first surface of the fixation key shaped according to the first virtual surface;

[0027] E) Manufacturing the support structure using the virtual model of the support structure calculated in step B) with a CAM process;

[0028] F) Applying the support structure produced in step E) to the toothed shells inserted into the fixing key and connecting the applied support structure to the toothed shells inserted into the fixing key; and

[0029] G) Attaching a denture base or a remaining denture base to the support structure or to the support structure and the tooth shells according to step F) or building up a denture base or a remaining denture base on the support structure or on the support structure and the tooth shells according to step F).

[0030] Preferably, the outer surface may be a vestibular surface and a coronal surface, or the outer surface may be a vestibular surface. Most preferably, the outer surface may include the entire vestibular surface. The vestibular surface is the outwardly facing (labially or buccally oriented) visible surface of the teeth, denture teeth, or dental veneers (i.e., above the gingival margin) and extends into the mesial areas.

[0031] According to step B), the virtual model of the support structure is calculated according to the invention such that 1. the support structure forms a partial volume of the virtual three-dimensional dental prosthesis model, that 2. the partial volume of the support structure has at least one tooth partial volume of several of the virtual prosthesis teeth, that 3. the at least one tooth partial volume is spaced away from the outer surfaces of the virtual prosthesis teeth or from partial areas of the outer surfaces of the virtual prosthesis teeth, and that 4. each of the at least one tooth partial volume connects several of the virtual prosthesis teeth in one piece.This calculates a support structure that lies partially or completely inside the denture tooth portion of the dental prosthesis (namely in the volume of the virtual denture teeth), and the support structure is then manufactured in step F), whereby the support structure can achieve mechanical stabilization of the dental prosthesis without affecting the external aesthetic appearance of the dental prosthesis.

[0032] A tooth partial volume of the virtual denture teeth is a partial volume of the denture teeth. The term "tooth partial volume" is used here to distinguish it from the partial volume of the virtual three-dimensional dental prosthesis model, which may additionally include parts of the volume of the virtual denture base.

[0033] If in step B) the at least one tooth partial volume is spaced away from partial areas of the outer surfaces of the virtual denture teeth, then the at least one tooth partial volume is preferably spaced away from vestibular surfaces and / or coronal surfaces of the virtual denture teeth, particularly preferably from vestibular surfaces or from vestibular and coronal surfaces of the virtual denture teeth, and most particularly preferably from the entire vestibular surface of the virtual denture teeth.

[0034] The fact that each of the at least one tooth part volume connects several of the virtual denture teeth in one piece means that the at least one tooth part volume each forms a contiguous volume that extends over several, preferably adjacent, denture teeth of the virtual model of the denture teeth.

[0035] The support structure can be constructed in one piece or in multiple pieces.

[0036] The support structure can be designed as a single piece with a contiguous volume or tooth-part volume, or it can be multi-part with several support structure parts, each having a contiguous volume or tooth-part volume, and the support structure parts themselves being single pieces. The tooth shells have a vestibular and / or coronal surface as their outer surface, which corresponds to the outer shape, i.e., the vestibular and / or coronal shape, of the virtual denture teeth in the virtual three-dimensional dental prosthesis model.The use of the term "remaining denture base" is based on the fact that the support structure can already include part of the denture base, and then not the entire denture base, but only the remaining denture base needs to be connected to the support structure to fabricate the denture base, or only the remaining denture base needs to be and can be produced. The fixation key is preferably made of or in a plastic, silicone, or silicone-based material in step C).

[0037] Particularly preferred is the material in which the first surface is created in step C) a slightly elastically deformable material or a rubber-elastic deformable material, such as silicone or hard rubber.

[0038] Preferably, the support structure and the tooth shells are bonded together during the joining process in step F). For this purpose, a bonding system, an adhesive, or a fluid polymerizable resin can be used, which is preferably applied to the basal surfaces of the tooth shells and / or to the surface of the support structure facing the tooth shells. Subsequently, the support structure is particularly preferably pressed onto the tooth shells, and the bonding system, adhesive, or polymerizable resin is partially cured or fully cured.

[0039] When calculating the virtual three-dimensional dental prosthesis model, the surfaces of known prefabricated tooth shells can be used as virtual models and positioned in the oral cavity during digital design so that they form the vestibular and / or coronal surfaces of the prosthetic teeth. When calculating the virtual three-dimensional model of the support structure, the basal and / or cervical surfaces of known prefabricated tooth shells can be used as virtual models to define at least parts of the coronal surface or the entire coronal surface of the support structure in the CAD model, in particular by defining the coronal surface or parts thereof as a negative form of the basal and / or cervical surfaces of the prefabricated tooth shells.The remaining coronal surface, if any, may be determined by the parts of the prosthetic teeth not covered by the tooth shells.

[0040] It may be provided that the support structure or the connected support structure parts in step B) are connected to each other via mesial connections of the prosthetic teeth. This allows the support structure to be interconnected within the volume for the prosthetic teeth.

[0041] It may also be provided that the parts of the support structure belonging to the prosthesis base in step B) are designed to be spaced away from the vestibular surface and preferably also from the lingual surface of the prosthesis base.

[0042] In the methods according to the invention, the tooth shells inserted into the fixing key in step D) can be prefabricated tooth shells, preferably prefabricated veneers. This allows existing tooth shells of high aesthetic quality to be used for the fabrication of the dental prosthesis. At the same time, particularly when using prefabricated tooth shells and veneers, a solid and therefore stable support structure can be used or manufactured, resulting in a particularly stable dental prosthesis.

[0043] In this context, a dental shell is understood to be a shell-like outer component for denture teeth, which can also be used as a facing for prepared natural teeth. It has an outer surface, preferably a vestibular surface or a vestibular and a coronal surface. Dental shells can be, for example, veneers or facing shells. The advantage of using dental shells lies in their high optical quality, resulting in a particularly good aesthetic appearance of the dental prosthesis produced with them. For example, dental shells can be opaque and exhibit a translucency that corresponds to the appearance of natural teeth or tooth enamel.The support structure can be designed to be particularly pressure-resistant and does not require opacity or transparency, but may preferably also be made of a white or tooth-colored material so as not to impair the aesthetic impression behind the tooth shells or the surfaces facing the oral cavity of the areas of the prosthetic teeth not covered by the tooth shells.

[0044] The veneers are preferably made of a hard, tooth-colored plastic or a tooth-colored ceramic, such as a zirconia ceramic. For example, PalaVeneer® veneer teeth from Külzer GmbH can be used.

[0045] Furthermore, it may be planned that the following steps will be carried out:

[0046] H) Calculating a connection surface between the support structure and the tooth shells on the one hand and the denture base or the remaining denture base on the other hand; and I) fabricating the connection surface calculated in step H) into the basal side of the support structure and the tooth shells connected to it after step F) and before step G); wherein in step G) the denture base or the remaining denture base is attached to the connection surface fabricated in step I) or the denture base is built up onto the connection surface fabricated in step I).

[0047] This ensures a particularly good fit between the tooth shells and the support structure with the denture base, and further automates the process. In particular, prefabricated denture bases or denture base preforms can be used and connected to the joining surface.

[0048] Preferably, the connection surface is produced in step I) using a subtractive CAM process. For this purpose, it is particularly preferred that the support structure is calculated in step B) with an interference on the basal side and produced in step E) with an interference on the basal side.

[0049] Furthermore, it may be provided that, prior to step A), the three-dimensional virtual dental prosthesis model is calculated using a CAD method by arranging virtual three-dimensional tooth models of the tooth shells, in particular prefabricated tooth shells, in a patient-specific virtual oral cavity model, wherein preferably the virtual prosthesis teeth of the virtual three-dimensional dental prosthesis model include the virtual three-dimensional tooth models of the tooth shells and particularly preferably the virtual prosthesis base connects the virtual prosthesis teeth with the patient-specific virtual oral cavity model.

[0050] This allows the three-dimensional virtual dental prosthesis model, and thus the dental prosthesis to be manufactured, to be calculated based on existing, preferably prefabricated, tooth shells with high functionality and high aesthetic appearance.

[0051] It may also be provided that the calculation of the virtual model of the fixing key in step A) is carried out in such a way that the position and orientation of the virtual prosthetic teeth relative to each other for the calculation of the first negative for the virtual first surface of the virtual model of the fixing key corresponds to the position and orientation of the virtual prosthetic teeth relative to each other in the virtual three-dimensional dental prosthesis model, preferably exactly to the position and orientation of the virtual prosthetic teeth relative to each other in the virtual three-dimensional dental prosthesis model.

[0052] This ensures that the fixing key is optimally adapted to the shape of the tooth shells, thereby guaranteeing a stable and positionally accurate arrangement of the tooth shells according to the virtual three-dimensional dental prosthesis model.

[0053] According to a preferred embodiment of the invention, the support structure may comprise several separate support structure parts, each of which has its own contiguous partial volume of the virtual three-dimensional dental prosthesis model, which is separate from the other partial volumes of the other support structure parts, wherein preferably the partial volumes of the support structure parts each comprise a contiguous tooth partial volume of several virtual prosthesis teeth, in particular of several adjacent virtual prosthesis teeth, wherein the tooth partial volumes are spaced apart from the outer surfaces of the virtual prosthesis teeth or from partial areas of the outer surfaces of the virtual prosthesis teeth, and wherein several tooth partial volumes of several virtual prosthesis teeth of the same partial volume are joined together in one piece.This allows for the placement of support structure components within the dental prosthesis that are tailored to the functions of the denture teeth. For example, molar denture teeth can be optimized with support structures offering high shear strength to withstand shearing movements during grinding, while incisive denture teeth can be supported with particularly pressure-resistant support structures.

[0054] Furthermore, it may be provided that, in step A) the virtual model of the fixing key is calculated, a second virtual surface of the virtual model of the fixing key is calculated as a second negative from the outer shape of vestibular surfaces of the virtual denture base of the virtual three-dimensional dental prosthesis model, wherein preferably the denture base or the remaining denture base is attached to the fixing key equipped with the tooth shells and the support structure in step G) such that at least a part of a vestibular surface of the denture base or the remaining denture base is attached to a second surface of the fixing key shaped according to the second virtual surface, or the denture base or the remaining denture base is built up in step G) on the support structure or the support structure and the tooth shells in the fixing key in such a way thatthat a second surface of the fixing key, shaped according to the second virtual surface, forms the entire vestibular surface of the prosthesis base or the remaining prosthesis base, or at least a part of the vestibular surface of the prosthesis base or the remaining prosthesis base, wherein particularly preferably at least the vestibular marginal rim of the prosthesis base or the remaining prosthesis base is formed by the second surface of the fixing key shaped according to the second virtual surface.

[0055] This achieves a precise connection between the denture base or the remaining denture base and the support structure, and thus with the denture teeth, or it achieves a precise fit between the denture base or the remaining denture base and the support structure, and thus with the denture teeth.

[0056] Furthermore, it may be provided that in step G) the denture base or the remaining denture base is arranged on the tooth shells and the support structure, wherein the denture base or the remaining denture base has tooth sockets and / or at least one tooth groove along a tooth arch of the denture base or the remaining denture base for receiving basal ends of the support structure or the support structure and the tooth shells, wherein preferably the denture base or the remaining denture base is placed on the fixing key equipped with the tooth shells and the support structure in such a way that the basal ends of the support structure or the support structure and the tooth shells are arranged spaced apart from the tooth sockets and / or the at least one tooth groove.This ensures particularly precise positioning of the denture base or the remaining denture base relative to the tooth shells and the support structure or to the denture teeth, because any deviations in the manufacturing process can be compensated for by a differently shaped and differently thick adhesive gap between the denture base or the remaining denture base.

[0057] It may be provided that during step G) a fluid adhesive or resin is applied to the tooth sockets and / or the at least one tooth groove and / or to the basal sides of the support structure of the tooth shells and / or after step G) a fluid adhesive or resin is introduced into a space between the basal side of the support structure and the tooth shells on the one hand and the tooth sockets and / or the at least one tooth groove on the other, wherein in all cases the fluid adhesive or resin subsequently directly bonds the support structure and the denture base or the remaining denture base and / or bridges or fills the gap between the basal side of the support structure and the tooth shells on the one hand and the tooth sockets and / or the at least one tooth groove on the other, wherein the fluid adhesive or resin is preferably cured afterwards.

[0058] Furthermore, it may be provided that, after the prosthesis base or the remaining prosthesis base has been arranged on the tooth shells and the support structure, a fluid adhesive or resin is introduced into a space between the basal ends of the tooth shells and the support structure on the one hand and the tooth sockets and / or the at least one tooth groove on the other, by pressing the fluid adhesive or resin into the space from the lingual or palatal side, wherein preferably at least one channel is created in the retention key before pressing in the fluid adhesive or resin, in particular by centrally cutting the material of the retention key, wherein the fluid adhesive or resin is pressed and guided through the at least one channel into the space.

[0059] This allows inaccuracies in the fabrication of the denture base and the support structure to be compensated for by precisely positioning the denture base relative to the support structure and the tooth shells. Additionally, the fixing key can be used to shape the vestibular marginal margin from the adhesive or resin.

[0060] It may be provided that the tooth shells and the support structure are made of different materials, preferably the support structure being made of at least one material with a higher flexural strength than the material of the tooth shells and / or of at least one material with a flexural strength of at least 3000 MPa / Nm 3 This allows the supporting structure to absorb the mechanical stresses of chewing effectively, while the tooth shells can be optimized in terms of hardness and aesthetic properties.

[0061] The bending strength is preferably determined using a three-point bending test according to DIN EN ISO 178 (2019-08).

[0062] It may also be provided that in step E) the support structure is manufactured using a subtractive or additive CAM process, preferably using an additive CAM process.

[0063] This enables rapid production of the support structure. To improve the accuracy of the support structure's production, subtractive post-processing of the additively manufactured support structure can be performed, preferably using a subtractive CAM process based on the virtual model of the support structure calculated in step B).Furthermore, it can be provided that in step F) the support structure is connected to the tooth shells by means of a connecting agent, wherein preferably such an amount of the connecting agent is used between the tooth shells and the support structure that excess connecting agent, when the support structure is applied to the tooth shells inserted in the fixing key, escapes between the support structure and the tooth shells, comes into contact with the fixing key and thereby, when the connecting agent hardens, the fixing key is attached or bonded to the tooth shells and the support structure, wherein the connecting agent escaping between the support structure and the tooth shells particularly preferably wets the fixing key.

[0064] This fixes or glues the fixing key to the tooth shells and the support structure, thereby simplifying the subsequent fabrication of the dental prosthesis, in particular the joining or construction of the denture base or the remaining denture base. The fixing key, with the denture teeth attached to it from the tooth shells and the support structure, can thus be easily reused, and the support structure and the tooth shells can be worked on basally while they are held in the fixing key.

[0065] Alternatively, according to the invention, the fixing key can also be glued or connected separately to the tooth shells.

[0066] The bonding agent is preferably a fluid adhesive or a fluid polymerizable plastic, wherein the fluid adhesive or the fluid polymerizable plastic is cured or partially cured after the parts have been arranged relative to each other, while the toothed shells and the support structure are held in the fixing key. The emerging bonding agent or the emerging adhesive contacts or wets the fixing key, particularly in an area adjacent to the first negative.

[0067] It may also be provided that after step G) the fixing key and the excess connecting material are removed, wherein preferably the dental prosthesis after step G) is processed according to the virtual three-dimensional dental prosthesis model by means of a subtractive CAM process and all excess material is removed from the dental prosthesis, in particular all excess material of the prosthesis base and the connecting material as well as the fixing key or remnants of the fixing key are removed.

[0068] This means that, apart from possible final polishing and / or surface treatment, the dental prosthesis is already finished and ready for immediate use. The process is thus further completed through additional automated steps.

[0069] Furthermore, it may be provided that after step G) the fixing key is removed, wherein preferably the dental prosthesis is processed after step G) according to the virtual three-dimensional dental prosthesis model using a subtractive CAM process, whereby all excess material, in particular from the prosthesis base and the fixing key or remnants of the fixing key, is removed from the dental prosthesis. It may be particularly preferably provided that after the removal of the fixing key and, if applicable, the final subtractive CAM processing of the dental prosthesis, a final finishing step is carried out by polishing, surface finishing, cleaning, removal of any remaining retention bars and / or deburring of the dental prosthesis.

[0070] Furthermore, it can be provided that the support structure consists of a PMMA or a ceramic or of a combination of a PMMA or a ceramic with a metallic material, wherein preferably the metallic material is exposed on a basal side of the support structure or is embedded in the PMMA or the ceramic.

[0071] These materials are particularly well suited for use in support structures and can also be easily made tooth-colored.

[0072] Preferably, highly cross-linked PMMA can be used, or a ZrO2 ceramic can be used. As a metallic material, stainless steel, medical-grade steel, or titanium can preferably be used.

[0073] Furthermore, it may be possible to include additional bar structures or reinforcement structures when calculating the virtual model of the support structure in step B) and when manufacturing the support structure in step E), and / or to include fasteners for attaching the dental prosthesis to teeth or implant abutments. This allows the support structure to be made particularly stable and to be attached to teeth, tooth stumps, or implants in the oral cavity.

[0074] Furthermore, it may be provided that an excess is provided when calculating the virtual model of the support structure in step B) and when manufacturing the support structure in step E), in particular an excess of 0.1 to 1 mm, which is removed in the area of ​​the connection to the denture base or to the remaining denture base before step G) according to a connection surface between the support structure and the tooth shells on the one hand and the denture base or the remaining denture base on the other hand using a subtractive CAM process and / or is removed from the areas protruding after step G) in comparison with the virtual three-dimensional dental prosthesis model using a subtractive CAM process.

[0075] This allows for the compensation of minor deviations and errors in manufacturing through subtractive machining after the support structure has been attached to the tooth shells, particularly when creating a connection surface for joining the support structure to a denture base or the rest of the denture base, or through final subtractive finishing. This ensures that sufficient volume of the support structure remains to allow for material removal at any point to achieve the target dimensions.

[0076] Furthermore, it may be provided that when calculating the virtual model of the support structure in step B) and when manufacturing the support structure in step E), a basal excess is provided on the basal side of the support structure, in particular an excess of 10 pm to 120 pm, wherein preferably the basal excess in the area of ​​the connection to the denture base or to the remaining denture base is removed before step G) according to a connection surface between the support structure and the tooth shells on the one hand and the denture base or the remaining denture base on the other hand using a subtractive CAM process.

[0077] In this way, the strength or thickness of the bonding agent between the tooth shells and the fixing key can be compensated for. By reducing the thickness of the support structure, particularly by 10 pm to 120 pm, the thickness of the adhesive or bonding agent between the recesses in the fixing key and the tooth shells can be compensated for. While this means the distance between the basal side of the support structure and the coronal surface of the tooth shells depends on the thickness of the adhesive layer, this layer is removed in the final step anyway. For this purpose, the minimum thickness of the support structure is increased to ensure sufficient material thickness in all cases.

[0078] Preferably, it may also be provided that the fixing key has walls projecting in a basal direction, or that walls are connected to the fixing key before step G) so that the walls project in a basal direction, wherein in step G) for the production of the denture base or the remaining denture base, a polymerizable plastic is filled into the cavity laterally bounded by the walls on the basal end of the support structure, is cured or partially cured there, and subsequently, using a subtractive CAM process according to the virtual three-dimensional dental prosthesis model, the denture base is manufactured from the cured or partially cured polymerizable plastic, or parts of the denture base are manufactured from the cured or partially cured polymerizable plastic.

[0079] This allows the denture base or the remaining denture base to be easily milled wholly or partially from a suitably cast plastic block, which is then directly connected to the basal surface of the support structure and, if applicable, the tooth shells by pouring.

[0080] Furthermore, it may be provided that the support structure in step E) is produced by laser sintering from a ceramic powder, in particular from a zirconium oxide ceramic powder.

[0081] This allows for the production and use of a particularly hard support structure made of ceramic materials.

[0082] According to a preferred embodiment of the inventive method, it can be provided that the virtual model of the support structure is generated in step B) with a lattice structure, undercuts and / or cavities, wherein in step G) the material for the denture base or the remaining denture base or an adhesive for connecting the denture base or the remaining denture base with the support structure and the tooth shells penetrates the lattice structure, undercuts and / or cavities and thereby creates a mechanically stable connection between the denture base or the remaining denture base and the support structure.

[0083] This allows for a particularly stable connection of the support structure to the prosthesis base or the rest of the prosthesis base. Furthermore, this method saves material in the production of the support structure. The lattice structure is particularly preferred. These structures can be manufactured very easily and efficiently using laser sintering.

[0084] Furthermore, it may be provided that at least one functional element accessible from the basal side of the dental prosthesis is attached to the support structure, wherein preferably the functional element is a bar or a matrix and / or the support structure has a recess for receiving the at least one functional element.

[0085] This allows the stable support structure to be used for attaching fastening elements such as bars and rails, which in turn serve to secure the dental prosthesis in the oral cavity, for example to teeth or implant abutments.

[0086] It can also be provided that the locking key is manufactured in step C) from a milling body which has a circumferential outer geometry open on one or both sides made of a dimensionally stable material and an inner area made of an elastically deformable material, wherein in step C) the locking key is milled out of the inner area, wherein preferably the outer geometry has retentions or a grid structure on its inner side to improve the mechanical connection to the inner area and / or the outer geometry encloses the inner area in the form of a cylindrical tube section and the inner area is a cylindrical disc which is positively enclosed by the outer geometry.

[0087] Such a locking key can be easily attached to computer-controlled milling machines and used for subtractive CAM processes. The tooth shells and support structure fixed in this locking key can also be easily machined subtractively while held in the CAM fixture by the locking key, which is manufactured from the milling body. During steps C), D), F), and G), and also for post-processing, the locking key can remain fixed in the CAM fixture, thus preventing positioning errors during re-clamping.

[0088] It may be provided that the outer geometry consists of a plastic, in particular PMMA, and / or that the inner area has a Shore hardness between 70 and 90, in particular consisting essentially of or entirely of a silicone with a Shore hardness (Shore A) of at least 70 and at most 90.

[0089] Furthermore, it may be provided that all inward-facing surfaces of the virtual model of the fixing key in step A) are calculated as a negative form of vestibular surfaces of the virtual three-dimensional dental prosthesis model or a virtual dental prosthesis outer contour of the virtual three-dimensional dental prosthesis model.

[0090] This allows for a particularly good fit and stable hold due to the flush connection of the tooth shells with the fixing key.

[0091] It may be possible to computationally split the virtual three-dimensional dental prosthesis model into a three-dimensional model of the virtual prosthesis teeth and a virtual three-dimensional model of the prosthesis base using file splitting, or to computationally split the virtual three-dimensional dental prosthesis model into a virtual three-dimensional model of the tooth shells, a virtual three-dimensional model of the prosthesis base, and a virtual three-dimensional model of the support structure. Alternatively, the support structure can be computationally determined from the virtual three-dimensional dental prosthesis model or from the virtual prosthesis teeth using file splitting.

[0092] Furthermore, it can be provided that in step C) the fixing key is manufactured from a milling body with a holding geometry for fixing in a CAM device, wherein the holding geometry remains firmly connected to the fixing key and the fixing key with the tooth shells and the support structure is fixed via the holding geometry in a CAM device for machining by means of subtractive CAM methods and the tooth shells and / or the support structure are machined by a CAM method while the tooth shells and the support structure are held in the fixing key, wherein preferably the holding geometry has an outer ring that is firmly and positively connected to the rest of the milling body or the rest of the fixing key, and the holding geometry has at least one fastening element on the outside for fixing the milling body or the fixing key in the CAM device.

[0093] This allows for a stable attachment of the locking key to the subtractive CAM device, and the locking key can remain fixed to avoid deviations in positioning even during steps C) to G) and, if necessary, during post-processing.

[0094] It may be provided that the virtual three-dimensional dental prosthesis model is generated based on an intraoral scan or a scan of an impression of the oral cavity for shaping the virtual prosthesis base and by a virtual setup of virtual models of prefabricated prosthesis teeth or prefabricated tooth shells in the virtual prosthesis base, wherein the shape, position and / or orientation of the virtual prosthesis teeth or the virtual tooth shells is preferably selected by a simulation of the position of the dental prosthesis in the patient's oral cavity and / or by a simulation of the position and orientation of the virtual prosthesis teeth or the virtual tooth shells relative to each other and / or to the virtual prosthesis base, wherein the occlusal plane and / or the masticatory movements of the oral cavity are particularly preferably simulated.to define the positions of the virtual denture teeth or the virtual tooth shells in the virtual three-dimensional dental prosthesis model. At least one of the problems underlying the present invention or arising from the prior art is also solved by a dental prosthesis comprising a denture base and several denture teeth, wherein the dental prosthesis has a support structure and tooth shells, wherein the tooth shells are parts of the denture teeth and form an outer surface of the denture teeth, wherein the support structure forms a partial volume of the dental prosthesis, and wherein the partial volume of the support structure comprises at least one tooth partial volume of several of the denture teeth of the dental prosthesis.wherein the at least one tooth-part volume is spaced apart from the outer surfaces of the denture teeth or from portions of the outer surfaces of the denture teeth, and wherein each of the at least one tooth-part volume of the support structure connects several of the denture teeth of the dental prosthesis in one piece, wherein the support structure and the tooth shells are connected flush with one another via a connecting element, wherein the tooth shells form the remaining denture teeth not consisting of the support structure and the connecting element, and wherein the denture base or the remaining denture base not formed by the support structure is firmly and flush connected to the support structure or to the support structure and one, more, or all of the tooth shells. The support structure may be a single piece with a continuous volume, or it may be multi-part with multiple support structure parts.wherein the support structure parts each have a contiguous volume and are one piece.

[0095] Preferably, the outer surface may be a vestibular surface and a coronal surface, or the outer surface may be a vestibular surface. Most preferably, the outer surface may include the entire vestibular surface. The vestibular surface is the outwardly facing (labially or buccally oriented) visible surface of the teeth, denture teeth, or dental veneers (i.e., above the gingival margin) and extends into the mesial areas.

[0096] It may be provided that the dental prosthesis is manufactured using a previously described method, in particular a method according to the invention.

[0097] The dental prosthesis then has the advantages described in the procedure.

[0098] Furthermore, it may be provided that the connecting agent fills the space between the support structure and the tooth shells and / or that the connecting agent is a cured adhesive, a cured plastic or a cured PMMA.

[0099] This ensures a stable connection between the support structure and the tooth shells.

[0100] It may be intended that the dental shells are prefabricated, preferably prefabricated veneers. Preferably, the dental shells consist of a hard, tooth-colored plastic or a tooth-colored ceramic, for example, a cerclage ceramic. For example, PalaVeneer® shell teeth from Külzer GmbH can be used.

[0101] It can also be provided that the prosthesis base or the remaining prosthesis base is connected to the support structure via a connecting surface in the support structure, preferably the connecting surface being manufactured using a subtractive CAM process.

[0102] Furthermore, it can be provided that the support structure has several separate support structure parts, each of which has its own contiguous partial volume of the dental prosthesis, which is separate from the other partial volumes of the other support structure parts, wherein preferably the partial volumes of the support structure parts each have a contiguous tooth partial volume of several prosthesis teeth, in particular of several adjacent prosthesis teeth, wherein the tooth partial volumes are spaced apart from the outer surfaces of the prosthesis teeth or from partial areas of the outer surfaces of the prosthesis teeth, and wherein several tooth partial volumes of several prosthesis teeth of the same partial volume are connected to each other in one piece.

[0103] This allows for the arrangement of support structures within the dental prosthesis that are tailored to the functions of the denture teeth. For example, molar denture teeth can be optimized with support structures to absorb forces during shearing movements when the denture teeth are chewed, while incisive denture teeth can be built up with particularly pressure-resistant support structures.

[0104] Furthermore, it can be provided that the tooth shells and the support structure consist of different materials, wherein preferably the support structure consists of at least one material with a higher flexural strength than the material of the tooth shells and / or of at least one material with a flexural strength of at least 3000 MPa / Nm 3 consists.

[0105] This allows the supporting structure to absorb the mechanical stresses of chewing effectively, while the tooth shells can be optimized in terms of hardness and aesthetic properties.

[0106] The bending strength is preferably determined using a three-point bending test according to DIN EN ISO 178 (2019-08).

[0107] The support structure can be manufactured using a subtractive or additive CAM process, preferably an additive CAM process. This allows for rapid production of the support structure. To improve the accuracy of the support structure's production, subtractive post-processing of the additively manufactured support structure can be performed, preferably using a subtractive CAM process based on the virtual model of the support structure calculated in step B). It is also preferable that the prosthesis base is manufactured or completed, at least partially, using a subtractive CAM process.

[0108] The bonding agent is preferably a fluid adhesive or a fluid polymerizable plastic, wherein the fluid adhesive or the fluid polymerizable plastic is cured after the parts have been arranged relative to each other to bond the support structure to the tooth shells, while the tooth shells and the support structure are held in the fixing key.

[0109] It can also be provided that the support structure consists of a plastic, a PMMA and / or a ceramic or of a combination of a plastic, a PMMA or a ceramic with a metallic material, wherein preferably the metallic material is exposed on a basal side of the support structure or is embedded in the plastic, in which the PMMA or in the ceramic is exposed.

[0110] These materials are particularly well suited for use in support structures and can also be easily made tooth-colored.

[0111] Preferably, highly cross-linked PMMA can be used, and / or a ZrC>2 ceramic can be used. Preferably, stainless steel, medical-grade steel, or titanium can be used as the metallic material.

[0112] Furthermore, the support structure may include additional bar structures or reinforcement structures and / or fastening means for attaching the dental prosthesis to teeth or implant abutments.

[0113] This allows the support structure to be designed to be particularly stable, and the stable support structure can be attached to teeth, tooth stumps or implants in the oral cavity.

[0114] Preferably, the support structure may also have a lattice structure, undercuts and / or cavities, wherein the material of the denture base or the remaining denture base or a connecting means for connecting the denture base or the remaining denture base to the support structure and / or the tooth shells partially or completely fills the lattice structure, undercuts and / or cavities.

[0115] This allows for a particularly stable connection of the support structure to the denture base or the remaining denture base and / or the tooth shells. Furthermore, this method saves material in the fabrication of the support structure. The lattice structure is particularly preferred. These structures are especially easy to manufacture using laser sintering and enable a particularly stable connection.

[0116] Furthermore, the dental prosthesis may be designed with a fixing key that is flush with or glued to the outer surfaces of the prosthetic teeth. This allows for secure transport and further processing of the dental prosthesis while it is held in the fixing key.

[0117] At least one of the problems underlying the present invention or arising from the prior art is also solved by a device or combination of devices for carrying out a previously described, in particular inventive, method comprising a CAM device and a computer programmed for calculating the virtual models and for controlling the CAM device according to one of the previously described methods.

[0118] It may be provided that the device has:

[0119] a fixing key surface calculation module for calculating the first surface of the virtual model of the fixing key according to step A);

[0120] a locking key control module for a CAM device, in particular for a subtractive CAM device, programmed to control the subtractive production of the surfaces calculated with the locking key surface calculation module in a milling body;

[0121] a support structure calculation module for calculating the outer shape of the support structure according to step B); and

[0122] a support structure control module for a CAM device, in particular for an additive CAM device, programmed to control the production of the support structure calculated with the support structure calculation module; and

[0123] preferably a machining control module for a CAM device programmed to control the subtractive machining of the basal side of the tooth shells inserted into the fixing key and the support structure according to a connection surface which is particularly preferably calculable with a connection surface calculation module of the device.

[0124] This means that the device specifically comprises the individual elements that are suitable for implementing the method according to the invention.

[0125] It may be provided that the support structure or the connected support structure components are linked to each other via mesial connections of the denture teeth. This allows the support structure to be interconnected within the volume for the denture teeth. It may also be provided that the portions of the support structure belonging to the denture base are spaced from the vestibular surface and preferably also from the lingual surface of the denture base.

[0126] The invention is based on the surprising finding that by inserting a support structure onto tooth shells fixed in a fixing key according to a digitally constructed virtual three-dimensional dental prosthesis model, and subsequently attaching, building up, or completing a prosthesis base, it is possible to produce a highly aesthetic and simultaneously mechanically stable dental prosthesis using digital manufacturing methods. Furthermore, the use of the fixing key allows for high accuracy in the fabrication of the dental prosthesis according to the digitally constructed dental prosthesis model. The method described here enables a digitally based, individualized design, a functionally optimized combination of various suitable materials, and the achievement of a high level of aesthetics.The use of the fixing key allows for easy handling of the components and enables the production of a dental prosthesis that corresponds particularly precisely to the virtual three-dimensional dental prosthesis model.

[0127] The inventive method enables the precise combination with components that cannot be manufactured directly, such as prefabricated tooth shells, and the integration of further support, retention, and attachment elements, especially for partial dentures. The result is a perfect or at least improved fit of the overall geometry with respect to the CAD data set, despite the multi-component manufacturing process. Simultaneously, a customized support structure allows for mechanical stabilization of the dental prosthesis, tailored to the specific patient. The method can be used to establish a workflow for the production of precisely fitting partial or complete dentures.

[0128] The invention is further based on the surprising finding that the fixing key makes it possible to provide a fit similar to a three-dimensional puzzle piece, enabling the precise positioning of the tooth shells on the support structure and the support structure itself on the denture base, or on the rest of the denture base, according to the virtual three-dimensional dental prosthesis model. For this purpose, the fixing key is manufactured as a shape matching the denture teeth or the tooth shells to be inserted, and can also be manufactured as a shape matching the outer shape of the denture base to be produced. This ensures that the tooth shells only need to be attached to the support structure and the denture base in the desired orientation and position relative to each other and to the denture base. This eliminates errors and unnecessary effort in positioning the tooth shells on the support structure and the denture base.The retention key can be digitally designed using a CAD / CAM process from the virtual models of the denture teeth and the denture base, and then manufactured using a CAM process. The necessary virtual models of the denture teeth and the denture base are already available when manufacturing a dental prosthesis using CAD / CAM technology and can therefore be used without significant additional effort.

[0129] The dental prosthesis produced using the inventive method exhibits high aesthetic appeal due to the integration of prefabricated tooth shells. The support structure and its components for the tooth-colored portion can be made of a different material, thereby reinforcing the prosthesis. The support structure connects the individual prefabricated tooth shells into segments, significantly strengthening the prosthesis mechanically and simultaneously simplifying its positioning and fixation within the retention key. Post-processing of the tooth-colored structures within the retention key results in high precision with respect to the tooth-colored and gum-colored portions of the prosthesis. The final prosthesis corresponds exactly to, or at least very closely to, the digital design compared to other aesthetically superior prostheses. Exemplary embodiments of the invention are described below.

[0130] An exemplary method according to the invention for manufacturing a dental prosthesis (complete or partial denture) can comprise the following steps: 1) Digital CAD design of the final geometry of the dental prosthesis to create the virtual three-dimensional model of the dental prosthesis. For this purpose, the data for the outer contour / monoblock of the dental prosthesis is provided. Additionally, a digital CAD model of the support structure to be manufactured separately, including the tooth-colored components, is created. In this way, three-dimensional data is generated as a virtual model of the support structure. Similarly, data for the entire denture base or for the remaining portion of the denture base can be calculated using CAD based on the virtual three-dimensional model of the dental prosthesis. A remaining portion of the denture base can be calculated if the support structure already incorporates parts of the denture base.Furthermore, surface data of the entire prosthetic teeth or tooth shells, as well as data of the entire prosthetic teeth, are generated. Optionally, for partial denture solutions, additional data, e.g., for retention structures or other support frameworks, can be available and included in the virtual models. When calculating the virtual three-dimensional dental prosthesis model, the surfaces of known prefabricated tooth shells or prosthetic teeth can be used as virtual models and, within the framework of the digital design, arranged in the oral cavity in such a way that they form the vestibular and / or coronal surfaces or the outer surfaces of the prosthetic teeth, and their basal (or cervical) sides define at least parts of the adjacent occlusal surface of the support structure.Furthermore, the fixing key is digitally designed using CAD with the aid of the virtual three-dimensional dental prosthesis model, whereby an inwardly oriented part of the virtual model of the fixing key serves as a negative form of the outer surfaces of the tooth shells in their arrangement and position specified in the dental prosthesis model. Additionally, a digital design of a connecting surface can be calculated using CAD, whereby the connecting surface links the support structure and, if applicable, the tooth shells on their basal side to the prosthesis base or the remaining prosthesis base.

[0131] 2) Fabrication of the support structure according to the model, optionally with additional components, particularly those required for partial dentures. These can be, for example, metallic or ceramic support, retention, or attachment elements. An additive manufacturing process (CAM), such as laser sintering, can be used to fabricate the support structure. The material used for the support structure preferably has higher strength than the tooth shells and good mechanical properties. The support structure can also be composed of several colors or material classes. The design may have a slight oversize compared to the final geometry.

[0132] 3) Manufacturing a fixing key for the subsequent precise positioning of the tooth shells according to the virtual model of the fixing key from a blank as a milling body using CAM, wherein the outer geometry of the blank is preferably retained so that the fixing key can remain clamped in the CAM device. For this purpose, a milling body with the following structure is preferably provided:

[0133] a. A circumferential, one-sided open outer geometry (reservoir blank) with a shape analogous to standard milling bodies. The support / outer geometry preferably consists of dimensionally stable material, such as PMMA;

[0134] b. the inner area of ​​the milling body consists of an elastic material, preferably a plastic or a flexible silicone with a Shore hardness of Shore A 70-90; c. the circumferential outer geometry may optionally include additional retentions or grid structures for better connection to the inner core.

[0135] The fixing key can have walls, or walls can be added for later filling with polymerizable material, from which the denture base or the rest of the denture base is then manufactured.

[0136] 4) Inserting the tooth shells into the fixing key, positioning them in the designated positions that correspond to the outer shape. The tooth shells preferably form the vestibular and coronal surfaces of the denture teeth, but can also be constructed like crowns and form all exposed parts of the denture teeth. 5) Applying a bonding system or adhesive to the exposed basal surfaces of the tooth shells and attaching the support structure, bonding it to the tooth shells in the fixing key. Preferably, the excess bonding system or adhesive can simultaneously fix the bonded support structure and the tooth shells to the fixing key; optionally, the support structure can also be bonded to the fixing key separately.

[0137] 6) Machining of the basally visible portions of the support structure located in the fixing key, and if necessary also of the tooth shells, and adaptation to a previously calculated bonding surface. Any deviations resulting from the bonding or excessively long prefabricated tooth shells can be precisely shortened in this step.

[0138] 7) Completing the parts located in the negative mold with polymerizable material or attaching and bonding an existing denture base or an existing remaining denture base that was manufactured using CAM technology based on the virtual model of the denture base or the remaining denture base.

[0139] 8) Milling the final geometry of the dental prosthesis according to the virtual three-dimensional dental prosthesis model and, if necessary, finishing according to established procedures. In principle, the fixing key generated during milling can either remain in the holding device of the CAM unit or be completely or partially removed from the milling body by milling. The dental prosthesis is then removed from the holder and finished. As a final step, the process can be completed with surface treatment by polishing and / or chemical treatment of the dental prosthesis.

[0140] The following are exemplary embodiments of the invention, illustrated by nine schematic figures and a flowchart, without limiting the invention. These figures show:

[0141] Figure 1: a schematic perspective view of a virtual three-dimensional dental prosthesis model;

[0142] Figure 2: a schematic perspective view of a top side of a milling body for producing a locking key for implementing a method according to the invention; Figure 3: a schematic perspective view of a locking key as part of and for implementing a method according to the invention;

[0143] Figure 4: a schematic perspective view of the locking key according to Figure 3 with six inserted toothed shells; Figure 5: a schematic perspective view of the locking key according to Figure 3 with a support structure but without toothed shells;

[0144] Figure 6: a schematic perspective view of the fixing key with the support structure according to Figure 5 from a frontal perspective;

[0145] Figure 7: a schematic perspective view of the fixing key with the inserted tooth shells, wherein the support structure according to Figure 5 is inserted into the tooth shells;

[0146] Figure 8: a schematic perspective view of a fixing key with the inserted tooth shells and support structure and with the attached prosthesis base preform; Figure 9: a schematic perspective view of a dental prosthesis manufactured using a method according to the invention; and

[0147] Figure 10: the process of a method according to the invention for manufacturing a dental prosthesis.

[0148] Figure 1 shows a schematic perspective view of a virtual three-dimensional dental prosthesis model 1. The virtual three-dimensional dental prosthesis model 1 can be computationally split into a virtual denture base 2 and virtual denture teeth 4 using file splitting. Furthermore, it can be separated into virtual tooth shells (not shown) and a virtual support structure (not shown), which can be calculated by appropriately splitting the virtual model of the denture teeth 4 or by appropriately splitting the virtual three-dimensional dental prosthesis model 1. Even during the CAD design of the virtual three-dimensional dental prosthesis model 1, the virtual denture base 2 and the virtual denture teeth 4, or the virtual tooth shells, can exist separately from each other.The virtual three-dimensional dental prosthesis model 1 can be generated using conventional methods. Within the scope of the present invention, it is proposed that, during the CAD design of the virtual three-dimensional dental prosthesis model 1, virtual models of existing prefabricated tooth shells are positioned in a virtual oral cavity model (not shown), and based on their positioning and orientation, the remaining virtual prosthesis teeth 4 and the virtual prosthesis base 2 are computationally added. The virtual three-dimensional dental prosthesis model 1 is a model of the dental prosthesis 90 to be produced (see Figure 9), which, according to the invention, should correspond as closely as possible to the virtual three-dimensional dental prosthesis model 1.For file splitting, the outer shapes of the virtual denture teeth 4 and the virtual denture base 2 can be separated from each other in the CAD model so that, when reassembled, they form the complete virtual three-dimensional dental prosthesis model 1. The virtual denture base 2 has a basal surface 5, which represents the surface that will later rest on the edentulous oral mucosa of the physical dental prosthesis 90. The virtual denture teeth 4 have a coronal surface 6, which faces the apex (occlusal). The virtual denture teeth 4 have a vestibular surface 7, which faces the vestibule (labial and buccal). The virtual denture base 2 also has a vestibular surface 8. The area of ​​the virtual denture base 2 adjacent to the virtual denture teeth 4 is referred to as the marginal rim 9.

[0149] The virtual denture base 2 can include a virtual palatal plate if it is intended for the upper jaw (as shown in Figure 1). A denture base for the lower jaw does not have a palatal plate; instead, a recess for the tongue and lingual frenulum will be provided.

[0150] The dental prosthesis 90 to be manufactured (see Figure 9) comprises physical denture teeth 94 and a physical denture base 92 for an upper jaw with a palatal plate 91, the denture teeth 94 being firmly connected to the denture base 92. In the finished dental prosthesis 90, the physical denture teeth 94 consist of tooth shells 95, which form the outer surfaces of the denture teeth 94, and of the support structure, which is not visible in Figure 9 because it is located internally within the dental prosthesis 90 or because it is located orally and within the dental prosthesis 90. The tooth shells 95 are made of a hard plastic or a tooth-colored (whitish or cream-colored) hard ceramic, while the physical denture base 92 in the finished dental prosthesis 90 consists, at least in its outer region 98, of a gum-colored (pink) plastic (see Figure 8).The denture teeth 94 or the tooth shells 95 have a coronal surface 96 oriented in the occlusal direction, which is preferably also formed by the tooth shells 95. The area of ​​the denture base 92 adjacent to the denture teeth 94 or the tooth shells 95 is referred to as the marginal margin 97, analogous to the anatomical terms used in a natural oral cavity. The physical denture base 92 has a vestibular surface 98 that faces the oral vestibule (labially and buccally). The physical denture teeth 94 or the tooth shells 95 have vestibular surfaces 99 that face the oral vestibule (in the labial and buccal direction) and that are formed by the tooth shells 95.

[0151] Figure 2 shows a schematic perspective view of a top side (top in Figure 1) of a milling body 11 for the production of a locking key for implementing a method according to the invention.

[0152] The milling body 11 preferably comprises a solid body 12 made of an elastic material such as silicone. Furthermore, the material of the solid body 12 should not be too hard, but at the same time should not crumble or break easily during milling. The solid body 12 has the shape of a cylindrical disk and preferably extends to a bottom surface opposite the top surface of the milling body 11 (not shown in Figure 2).

[0153] The milling body 11 has a two-sided open outer geometry 13 made of a dimensionally stable material. The outer geometry 13 may have retentions or a grid structure on its inner side to improve the mechanical connection to the solid body 12. The outer geometry 13 preferably encloses the cylindrical solid body 12 in a form-fitting manner, in the form of a cylindrical tube section.

[0154] A cavity 14 with a flat surface 16 can be arranged on the upper surface of the milling body 11, wherein the cavity 14 can be laterally bounded by a circumferential wall 18. The wall 18 can be a continuation of the outer geometry 13 and be formed integrally with the outer geometry 13. Alternatively, the outer geometry 13 can also be placed on the milling body 11. The surface 16 is formed (preferably completely) by the solid body 12. The circumferential wall 18 can be made of the same material as the outer geometry or of a different material. In particular, the circumferential wall 18 can be an annular body or a tube section that is placed on the solid body 12 or on the outer geometry 13 and firmly connected to it there. The connection can be made by adhesive bonding.The solid body 12 or the outer geometry 13 can have a step on its outer circumference, forming a circumferential wall 18, for attaching a ring body or pipe section, onto which the ring body or pipe section is flush-mounted. The circumferential wall 18 can also be a metal ring body.

[0155] A marking 19 for determining the fill level in the cavity 14 can be arranged on an inner surface of the circumferential wall 18 facing the cavity 14, or on an outer surface of a circumferential transparent wall 18. The marking 19 can also be added to the circumferential wall 18 during the process of manufacturing a dental prosthesis, for example, by milling it in. Using the marking 19, a fluid polymerizable resin to be filled into the cavity 14 for the production of the prosthesis base or the remaining prosthesis base (not shown in Figure 2) can be filled to the correct level.

[0156] At least one mounting bracket 20 for fixing the milling body 11 in a CAM device can be arranged on at least one outer wall of the milling body 11. The mounting bracket 20 can project from the outer wall of the milling body 11 as a torus with a rectangular cross-sectional area. As an alternative to the mounting bracket 20 shown in Figure 2, the mounting bracket can also be implemented in other ways, for example, by projecting projections or by recesses in the side surfaces. The mounting bracket 20 serves for attachment in a CAM device (not shown). Figure 3 shows a schematic perspective view of a locking wrench 21, which was manufactured from a milling body 22. The milling body 22 can be constructed as shown in Figure 2. For clarity, the milling body 22 is shown without a wall and mounting bracket, but can have these elements analogously to Figure 2.The milling body 22 can be surrounded externally by a ring-shaped outer geometry 23 made of a dimensionally stable material. Using a subtractive CAM process, recesses 24 in the form of negatives of denture teeth, corresponding to a virtual three-dimensional dental prosthesis model, were created in the flat surface of the milling body 22. For this purpose, the milling body 22 can be clamped with the holder into a CAM device such as a computer-controlled 4-axis milling machine. The recesses 24 are shaped in Figure 3 according to the negatives of the coronal, vestibular, and lingual surfaces of the virtual denture teeth of a virtual three-dimensional dental prosthesis model. Adjacent recesses 24 can be connected to each other via a yoke 26 to allow the construction and connection of continuous support structure components that connect the individual tooth positions (see Figures 5 and 6).Preferably, a yoke 26 may be arranged between each directly adjacent recess 24, which is deeper than a flat surface of the milling body 22 but less deep than the recesses 24.

[0157] Figure 4 shows a schematic perspective view of the fixing key 21 according to Figure 3, with tooth shells 28 inserted into the recesses 24. For clarity, the fixing key 21 is shown transparently in Figures 4 to 7, so that hidden structures are also visible, which are represented by dashed lines in Figures 4 to 7. The tooth shells 28 are preferably made of a hard plastic or ceramic and are tooth-colored. The tooth shells 28 have outer surfaces 30 that form the vestibular and coronal surfaces of the denture teeth 94 of the dental prosthesis 90 to be produced (see Figure 9). The tooth shells 28 rest with their outer surfaces 30 against the recesses 24 of the fixing key 21, so that the elastic fixing key 21 holds the tooth shells 28 in position according to the virtual three-dimensional dental prosthesis model.The tooth shells 28 are concave and shell-shaped in the oral direction (towards the oral cavity) and do not rest against the recesses 24 on the palatal or lingual side. The yokes 26 are preferably not completely covered by the tooth shells 28, so that space remains for a mesial connection of the denture teeth by the support structure 32.

[0158] Figure 5 shows a schematic perspective view of the fixing key 21 according to Figures 3 and 4, in which a support structure 32, or a support structure component thereof, is inserted into the recesses 24. Figure 6 shows the same setup as Figure 5 from a frontal perspective. The support structure 32 is shaped to fit the recesses 24 and the hollow sides of the tooth shells 28. For this purpose, the shape of the support structure 32 can be calculated according to the virtual three-dimensional dental prosthesis model and a negative of the palatal or lingual side of the virtual tooth shells, and then manufactured according to this model using an additive or subtractive CAM process. The support structure 32 can be made of one or more materials, such as highly cross-linked PMMA. The support structure 32 can, in particular, exhibit high flexural strength.For this purpose, struts can be arranged in the support structure 32. The support structure 32 can be tooth-colored, but does not have to meet the same aesthetic requirements as the tooth shells 28, because the support structure 32 is not visible from the outside, but is covered at least vestibularly and coronally by the tooth shells 28 in the finished dental prosthesis 90. The support structure 32 has a connecting surface 34 for connecting the support structure 32 to a prosthesis base 92 (see Figure 9). The connecting surface 34 can be subsequently incorporated into the support structure 32, which is already connected to the tooth shells 28 (see Figure 7). The support structure 32 has a contact surface 36 with the tooth shells 28, which lies flush against the tooth shells 28 when the support structure 32 is placed against the tooth shells 28 in the fixing key 21, as shown in Figure 7.The support structure 32 is preferably connected mesially in adjacent recesses 24 via the yokes 26 and is therefore a single piece.

[0159] Starting from Figure 4, the support structure 32 is bonded to the tooth shells 28 in a method according to the invention, while the tooth shells 28 are held in the fixing key 21, as shown in Figure 7. Preferably, adhesive (not shown) emerges between the tooth shells 28 and the support structure 32, at least partially wets the recesses 24 of the fixing key 21, and thus bonds not only the support structure 32 to the tooth shells 28 but also the tooth shells 28 and the support structure 32 to the fixing key 21. In this way, the tooth shells 28 and the support structure 32 are stably connected to the fixing key 21. Throughout the entire process, except for any final machining, the fixing key can remain fixed in the CAM device.

[0160] When a complete dental prosthesis is manufactured as a dental prosthesis, the recesses 24 which are not yet occupied in Figures 4 to 7 are also fitted with tooth shells and further support structure parts are connected to the palatal or lingual sides of the tooth shells, as shown for the tooth shells 28 and the support structure 32 in Figures 4 to 7.

[0161] After connecting the tooth shells 28 to the support structure 32, a denture base can be constructed on the connecting surface 34 or on the basal sides of the tooth shells 28 and the support structure 32. Various methods can be used for this purpose.

[0162] Firstly, a denture base can be created using CAM technology according to a virtual model of the denture base and this denture base can be glued onto the basal sides of the tooth shells 28 and the support structure 32.

[0163] Secondly, a fluid polymerizable resin can be poured onto the basal surfaces of the tooth shells 28 and the support structure 32, from which the denture base is milled after curing or partial curing. The wall 18 of the milling body 11, as shown in Figure 2, is helpful for this purpose.

[0164] Thirdly, as schematically illustrated in Figure 8, a denture base can be produced by creating a denture base preform 52 and filling a cavity 44 and space 56 with a fluid polymerizable resin. For this purpose, the fluid polymerizable resin can fill the spaces 56 between the basal connecting surface 34 and the denture base preform 52 and be fully or partially cured there. Subsequently, the denture base can be subtractively milled according to the virtual three-dimensional dental prosthesis model. Such a method is disclosed in EP 4389063 A1 and can also be applied in the present case. The denture base preform 52 already includes the palatal plate 54. During the fabrication of the denture base, the tooth shells 58 are held in place by a fixing key 41.The fixing key 41 comprises a solid body 40 with a cavity 44 within the solid body 40, which can be filled with the fluid polymerizable plastic. In a surface 46 of the solid body 40, which forms the bottom of the cavity 44, corresponding recesses (not visible in Figure 8) are arranged in which the toothed shells 58 and the support structure connected to the toothed shells 58 (not visible in Figure 8) are held. A circumferential wall 48 ensures that the filled fluid polymerizable plastic cannot overflow. In Figure 8, only a portion of the vestibular surface 60 of the toothed shells 58 is visible; this portion does not contact the surfaces of the recesses in the fixing key 41.

[0165] The result is a dental prosthesis 90, as shown schematically in Figure 9.

[0166] The following section explains an exemplary process using the models, intermediate products, and final products shown in Figures 1 to 9. The sequence of the exemplary process is shown schematically in Figure 10.

[0167] In an optional first step 101, a virtual three-dimensional dental prosthesis model 1 can be calculated using CAD. For this purpose, the anatomical conditions in the patient's oral cavity are used in a known manner with the aid of a virtual three-dimensional oral cavity model to calculate a suitable basal support for a virtual prosthesis base 2. The virtual prosthesis teeth 4 can be calculated in a known manner from data sets of prefabricated tooth shell shapes 28, 58, which are supplemented if necessary, by anatomically and / or articulatorily optimizing the arrangement of the virtual prosthesis teeth 4 in the oral cavity model and optimizing the position and location of the virtual prosthesis teeth 4 with regard to their functionality.The connection between the virtual denture base 1 and the virtual denture teeth 4 is then automatically generated using a CAD process, based on the virtual three-dimensional oral cavity model and, if necessary, with manual corrections. In particular, the coronal surfaces 6 and the vestibular surfaces 7 of the virtual denture teeth 4 are determined. Alternatively, an existing virtual three-dimensional dental prosthesis model can simply be used and displayed.

[0168] In a second step, 102, a virtual model of prosthetic teeth 4 and a virtual model of a prosthetic base 1, and optionally a virtual model of a marginal margin, are calculated from the virtual three-dimensional dental prosthesis model. This calculation can be performed, for example, using file splitting.

[0169] In a third work step 103, which can be carried out in parallel or before or after the second work step 102, a virtual model of a fixing key is calculated using the virtual denture teeth 4 and optionally also using the virtual denture base 1 and / or the virtual marginal rim, whereby the outer surfaces or the coronal surfaces 6 and the vestibular surfaces 7 of the denture teeth 4 are realized as a negative in the virtual model of the fixing key.

[0170] In a fourth step, 104, a virtual model of a support structure can be calculated by splitting the virtual model of the prosthetic teeth (4) and the virtual models of the prefabricated tooth shells. The virtual model of the support structure can also include additional parts of the denture base to achieve the desired mechanical stabilization. Furthermore, the virtual model of the support structure can include connecting elements for attachment to teeth or implant abutments in the oral cavity, or images for this purpose.

[0171] In an optional fifth step 105, a virtual model of a prosthesis base or a remaining prosthesis base can be calculated.

[0172] In a sixth step 106, a physical fixing key 21, 41 is produced according to the virtual model of the fixing key using a CAM process. For this purpose, a milling body 11, 22 can be clamped into a CAM device, and with the CAM device, according to the virtual model of the fixing key, recesses 24 corresponding to the negative of the outer surfaces of the virtual denture teeth 4 can be machined into the milling body 11, 22. In addition, further surfaces can be created, which are negatives of vestibular surfaces 8 of the virtual denture base 2.The fixing key 21, 41 contains recesses 24 which in their external shape correspond to negatives of the selected prefabricated tooth shells 28, 58, wherein the recesses 24 in their position and orientation to each other correspond to the position and orientation of the virtual prosthesis teeth 4 to each other in the virtual three-dimensional dental prosthesis model 1.

[0173] In a seventh step 107, the physical tooth shells 28, 58 are inserted into the fixing key 21, 41 according to the virtual model of the prosthetic teeth 4 and the virtual three-dimensional dental prosthesis model 1.

[0174] In an eighth step 108, a physical support structure 32 is manufactured from a material with high flexural strength using a CAM process, corresponding to the virtual model of the support structure. An additive CAM process is preferably used. The support structure 32 can be manufactured from several materials that are joined together during production.

[0175] In a ninth step 109, the support structure 32 is bonded with an adhesive to the tooth shells 28, 58, which are fixed and held in the fixing key 21, 41. Preferably, excess adhesive is released and bonds with the fixing key 21, 41, so that the fixing key 21, 41 is bonded to the tooth shells 28, 58 and the support structure. The tooth shells 28, 58 and the support structure 32, or parts of the support structure 32, together form the denture teeth 94 of the dental prosthesis 90.

[0176] In a tenth step 110, a connecting surface 34 on the basal side of the support structure 32 and the tooth shells 28, 58 can be calculated and produced using a subtractive CAM process, provided that this does not already result directly from the production of the support structure 32 without the need to remove any material.

[0177] Optionally, in an eleventh step 111, the surface for connection with the prosthesis base 92 or the rest of the prosthesis base, or the connecting surface 34, can be prepared to improve the connection, for example by cleaning, chemically swelling and / or roughening.

[0178] After the tenth step 110 or after the optional eleventh step 111, the following three methods can be used to connect or build upon the denture base 92 or the remaining denture base with the support structure 32 or with the support structure 32 and the tooth shells 28, 58. First, in a twelfth step 112, the denture base 92 or the remaining denture base can be manufactured according to the virtual three-dimensional model of the denture base 2 using a CAM process, and in a thirteenth step 113, it can be connected to the support structure 32 and the tooth shells 28, 58 by bonding it to the connecting surface 34.

[0179] Secondly, in a fourteenth step 114, a fluid polymerizable plastic can be filled into the cavity 14, 44 in order to produce the denture base 92 from this plastic after hardening or partial hardening in a fifteenth step 115, or to connect a denture base preform 52 with the connecting surface 34 or the support structure 32 and the tooth shells 28, 58 with this plastic (see Figure 8), wherein the denture base 92 is then produced from the hardened plastic and the denture base preform 52.

[0180] Thirdly, in a sixteenth step 116, the denture base 92 can be printed on the connecting surface 34 or on the support structure 32 and the tooth shells 28, 58 using an additive CAM process according to the virtual model of the denture base 2.

[0181] From this point on, the three alternative paths of the inventive method are merged again.

[0182] In an optional seventeenth step 117, the fixing key 21, 41 can be detached from the tooth shells 28, 58 and the support structure 32 or from the denture teeth 94 and the denture base 92, and preferably excess adhesive and / or plastic can also be removed.

[0183] In an optional eighteenth step 118, post-curing or final hardening of the dental prosthesis 90 or the plastics and / or adhesives can take place, if this has not already been done.

[0184] In a nineteenth step 119, the dental prosthesis 90 can be subtractively machined using a CAM process according to the virtual three-dimensional dental prosthesis model 1. Here, the dental prosthesis 90 can be milled, for example, with a CAM device such as a computer-controlled milling machine. This process also allows for the removal of remnants of the fixation key 21, 41 and excess adhesive or plastic. In particular, as a final step, connecting bridges (not shown) that link the inner fixation key to the outer geometry 13, 23, 43 and the retention 20, 50 can be removed, thus detaching the dental prosthesis 90 from the milling body 11, 22. Up to this nineteenth step 119, the milling body 11, 22 can remain in the CAM device without needing to be removed in between.This prevents errors in positioning when clamping the milling body 11, 22 anew.

[0185] As an optional twentieth step 120, the dental prosthesis 90 can undergo final processing, for example, surface treatment, cleaning and / or polishing of the dental prosthesis 90.

[0186] The features of the invention disclosed in the preceding description, as well as in the claims, figures and embodiments, can be essential for the realization of the invention in its various embodiments, both individually and in any combination.

[0187] Reference symbol list

[0188] 1 Virtual dental prosthesis model

[0189] 2 Virtual model of the prosthesis base

[0190] 4 Virtual model of the denture teeth

[0191] 5 Basal side of the prosthesis base (virtual model)

[0192] 6 Coronal surface of a prosthetic tooth (virtual model)

[0193] 7 Vestibular surface of a prosthetic tooth (virtual model)

[0194] 8 Vestibular surface of the prosthesis base (virtual model)

[0195] 9 Marginal hem (virtual model)

[0196] 11, 22 milling bodies

[0197] 12.40 full body

[0198] 13, 23, 43 Outer geometry / Ring

[0199] 14, 44 cavity

[0200] 16, 46 surface

[0201] 18, 48 wall

[0202] 19 Mark

[0203] 20, 50 bracket

[0204] 21.41 Fixing key

[0205] 24 In-depth study

[0206] 26 yoke

[0207] 28, 58 tooth shell

[0208] 30 Outer surface of the tooth shell

[0209] 32 Support structure

[0210] 34 Connection surface to the prosthesis base

[0211] 36 Contact surface to the tooth shell

[0212] 52 Denture base preform 54 Palatal plate

[0213] 56 space

[0214] 60 Vestibular surface of the tooth shell

[0215] 90 Dental prosthesis

[0216] 91 Palate plate

[0217] 92 Prosthetic base

[0218] 94 Prosthetic tooth

[0219] 95 tooth shell

[0220] 96 Coronal surface of a prosthetic tooth

[0221] 97 Marginal hem

[0222] 98 Vestibular surface of the prosthesis base

[0223] 99 Vestibular surface of a prosthetic tooth

[0224] 101 Optional step: Calculating a virtual three-dimensional dental prosthesis model

[0225] 102 Optional step: Calculating a virtual model of denture teeth and a virtual model of a denture base and optionally a virtual model of a marginal rim from the virtual three-dimensional dental prosthesis model

[0226] Step 103: Calculating a virtual model of a fixation key using the outer surfaces of the denture teeth and optionally the marginal rim; the outer surfaces of the denture teeth are realized as a negative in the virtual model of the fixation key.

[0227] Step 104: Calculating a virtual model of a support structure as a sub-area of ​​the denture teeth and optionally the denture base

[0228] 105 Optional step: Calculating a virtual model of a denture base or remaining denture base

[0229] Step 106: Manufacturing the fixing key according to the virtual model of the fixing key

[0230] Step 107: Inserting physical tooth shells into the fixation key according to the virtual model of the denture teeth.

[0231] Step 108: Creating the support structure according to the virtual model of the support structure

[0232] Step 109: Bonding the support structure to the denture teeth inserted in the fixing key, preferably using excess adhesive to bond the denture teeth to the fixing key.

[0233] Step 110: Calculating and creating a connection surface between the tooth shells and the support structure on the one hand, and a prosthesis base on the other, within the support structure and tooth shells fixed in the fixing key.

[0234] 111 Optional step: Preparing the joining surface of the denture teeth to improve the connection

[0235] Step 112: Manufacturing the remaining prosthesis base according to the virtual three-dimensional model of the prosthesis base

[0236] Step 113: Bonding the denture base to the bonding surface. Step 114: Applying a fluid resin to the bonding surface and curing or partial curing of the fluid resin.

[0237] Step 115: Manufacturing the denture base using a subtractive CAM process from the cured or partially cured plastic

[0238] Step 116: Printing the denture base using a CAM process. Optional step 117: Removing the fixing key from the dental prosthesis. Optional step 118: Post-curing or final curing of the dental prosthesis. Step 119: Final shaping of the dental prosthesis using a subtractive CAM process according to the virtual three-dimensional dental prosthesis model.

[0239] 120 Optional step: Final processing of the dental prosthesis

Claims

Patent claims 1. Method for manufacturing a dental prosthesis (90), wherein the dental prosthesis (90) comprises a denture base (92) and several denture teeth (94), wherein the denture base (92) comprises a gum-colored plastic, wherein the method is carried out using a virtual three-dimensional dental prosthesis model (1) of the dental prosthesis (90) to be manufactured, and wherein the virtual three-dimensional dental prosthesis model (1) comprises virtual denture teeth (4) and a virtual denture base (2), characterized by the following steps: A) Calculating a virtual model of a fixation key, wherein a virtual first surface of the virtual model of the fixation key is calculated as a first negative of the outer shape of outer surfaces of the virtual denture teeth (4), wherein the outer surfaces of the virtual denture teeth (4) include vestibular surfaces and / or coronal surfaces of the virtual denture teeth (4); B) Calculating a virtual model of a support structure with the specifications that the support structure forms a partial volume of the virtual three-dimensional dental prosthesis model (1), that the partial volume of the support structure has at least one tooth partial volume of several of the virtual prosthesis teeth (4), that the at least one tooth partial volume is spaced away from the outer surfaces of the virtual prosthesis teeth (4) or from partial areas of the outer surfaces of the virtual prosthesis teeth (4), and that each of the at least one tooth partial volume connects several of the virtual prosthesis teeth (4) in one piece; C) Manufacturing a fixing key (21, 41) using a CAM process based on the data of the virtual model of the fixing key calculated in step A); D) Inserting tooth shells (28, 58, 95) into the fixation key (21, 41) produced in step C), wherein the tooth shells (28, 58, 95) have outer surfaces that correspond at least partially to the outer surfaces of the virtual denture teeth (4), wherein the outer surfaces of the tooth shells (28, 58, 95) include vestibular surfaces and / or coronal surfaces of the tooth shells (28, 58, 95), and wherein the outer surfaces of the tooth shells (28, 58, 95) are placed against the first surface of the fixation key (21, 41) shaped according to the first virtual surface; E) Manufacturing the support structure (32) using the virtual model of the support structure calculated in step B) with a CAM process; F) Applying the support structure (32) produced in step E) to the tooth shells (28, 58, 95) inserted into the fixing key (21, 41) and connecting the applied Support structure (32) with the tooth shells (28, 58, 95) inserted into the fixing key (21, 41); and G) Attaching a denture base (92) or a remaining denture base to the support structure (32) or to the support structure (32) and the tooth shells (28, 58, 95) according to step F) or building up a denture base (92) or a remaining denture base on the support structure (32) or on the support structure (32) and the tooth shells (28, 58, 95) according to step F).

2. The method according to claim 1, characterized in that the tooth shells (28, 58, 95) which are inserted into the fixing key (21, 41) in step D) are prefabricated tooth shells, preferably prefabricated veneers.

3. Method according to claim 1 or 2, characterized by the additional steps H) calculating a connection surface (34) between the support structure (32) and the tooth shells (28, 58, 95) on the one hand and the denture base (92) or the remaining denture base on the other hand; and I) Producing the connection surface (34) calculated in step H) into the basal side of the support structure (32) and the associated tooth shells (28, 58, 95) after step F) and before step G); wherein in step G) the prosthesis base (92) or the remaining prosthesis base is attached to the connecting surface (34) produced in step I) or the prosthesis base (92) is built up onto the connecting surface (34) produced in step I).

4. Method according to one of the preceding claims, characterized by the additional steps Before step A), the three-dimensional virtual dental prosthesis model (1) is calculated by an arrangement of virtual three-dimensional tooth models of the tooth shells (28, 58, 95), in particular of prefabricated tooth shells, in a patient-specific virtual oral cavity model using a CAD method, wherein preferably the virtual prosthesis teeth (4) of the virtual three-dimensional dental prosthesis model (1) include the virtual three-dimensional tooth models of the tooth shells (28, 58, 95) and particularly preferably the virtual prosthesis base (2) connects the virtual prosthesis teeth (4) with the patient-specific virtual oral cavity model.

5. Method according to one of the preceding claims, characterized in that the calculation of the virtual model of the fixing key in step A) is carried out such that the position and orientation of the virtual denture teeth (4) relative to each other for the calculation of the first negative for the virtual first surface of the virtual model of the fixing key corresponds to the position and orientation of the virtual denture teeth (4) relative to each other in the virtual three-dimensional dental prosthesis model (1), preferably exactly corresponds to the position and orientation of the virtual denture teeth (4) relative to each other in the virtual three-dimensional dental prosthesis model (1).

6. A method according to one of the preceding claims, characterized in that the support structure (32) comprises several separate support structure parts, each of which has its own contiguous partial volume of the virtual three-dimensional dental prosthesis model (1) that is separate from the other partial volumes of the other support structure parts, wherein preferably the partial volumes of the support structure parts each comprise a contiguous tooth partial volume of several virtual prosthesis teeth (4), in particular of several adjacent virtual prosthesis teeth (4), wherein the tooth partial volumes are spaced apart from the outer surfaces of the virtual prosthesis teeth (4) or from partial areas of the outer surfaces of the virtual prosthesis teeth (4), and wherein several tooth partial volumes of several virtual prosthesis teeth (4) of the same partial volume are joined together in one piece.

7. Method according to one of the preceding claims, characterized in that, in calculating the virtual model of the fixation key in step A), a second virtual surface of the virtual model of the fixation key is calculated as a second negative from the outer shape of vestibular surfaces of the virtual denture base (2) of the virtual three-dimensional dental prosthesis model (1), wherein preferably the denture base (92) or the remaining denture base is applied in step G) to the fixation key (21, 41) equipped with the tooth shells (28, 58, 95) and the support structure (32) such that at least a part of a vestibular surface (98) of the denture base (92) or the remaining denture base is applied to a second surface of the fixation key (21, 41) shaped according to the second virtual surface.or the denture base (92) or the remaining denture base in step G) is built up on the support structure (32) or the support structure (32) and the tooth shells (28, 58, 95) in the fixation key (21, 41) in such a way that a second surface of the, shaped according to the second virtual surface, The fixing key (21, 41) forms the entire vestibular surface (98) of the prosthesis base (92) or the remaining prosthesis base, or at least a part of the vestibular surface (98) of the prosthesis base (92) or the remaining prosthesis base, wherein particularly preferably at least the vestibular marginal rim of the prosthesis base (92) or the remaining prosthesis base is formed by the second surface of the fixing key (21, 41) shaped according to the second virtual surface.

8. Method according to one of the preceding claims, characterized in that in step G) the denture base (92) or the remaining denture base is arranged on the tooth shells (28, 58, 95) and the support structure (32), wherein the denture base (92) or the remaining denture base has tooth sockets and / or at least one tooth groove along a tooth arch of the denture base (92) or the remaining denture base for receiving basal ends of the support structure (32) or the support structure (32) and the tooth shells (28, 58, 95), wherein preferably the denture base (92) or the remaining denture base is positioned on the fixing key (21, 41) equipped with the tooth shells (28, 58, 95) and the support structure (32) such that the basal ends of the support structure (32) or the support structure (32) and the Tooth shells (28, 58, 95) are arranged spaced apart from the tooth sockets and / or at least one tooth groove.

9. Method according to claim 8, characterized in that After the prosthesis base (92) or the remaining prosthesis base has been arranged on the tooth shells (28, 58, 95) and the support structure (32), a fluid adhesive or resin is introduced into a space (56) between the basal ends of the tooth shells (28, 58, 95) and the support structure (32) on the one hand and the tooth sockets and / or the at least one tooth groove on the other, by pressing the fluid adhesive or resin into the space (56) from the lingual or palatal side, wherein preferably at least one channel is created in the retention key (21, 41) before pressing in the fluid adhesive or resin, in particular by centrally cutting the material of the retention key (21, 41), wherein the fluid adhesive or resin is pressed and guided through the at least one channel into the space (56).

10. Method according to one of the preceding claims, characterized in that the tooth shells (28, 58, 95) and the support structure (32) are made of or manufactured from different materials, wherein the support structure (32) is preferably made of at least one material with a higher flexural strength than the material of the tooth shells (28, 58, 95) and / or at least one material with a flexural strength of at least 3000 MPa / Nm 3 consists.

11. Method according to one of the preceding claims, characterized in that in step E) the support structure (32) is produced using a subtractive or additive CAM process, preferably using an additive CAM process.

12. A method according to one of the preceding claims, characterized in that in step F) the support structure (32) is connected to the tooth shells (28, 58, 95) by means of a connecting element, wherein preferably such an amount of the connecting element is used between the tooth shells (28, 58, 95) and the support structure (32) that excess connecting element, when the support structure (32) is applied to the tooth shells (28, 58, 95) inserted in the fixing key (21, 41), escapes between the support structure (32) and the tooth shells (28, 58, 95), comes into contact with the fixing key (21, 41), and thereby, upon curing of the connecting element, the fixing key (21, 41) is attached or bonded to the tooth shells (28, 58, 95) and the support structure (32), wherein the connection between the support structure is particularly preferably (32) and the connecting agent emerging from the tooth shells (28, 58, 95) wets the fixing key (21, 41).

13. Method according to claim 12, characterized in that after step G) the fixing key (21, 41) and the excess connecting element are removed, wherein preferably the dental prosthesis (90) is processed after step G) according to the virtual three-dimensional dental prosthesis model (1) by means of a subtractive CAM process and all excess material is removed from the dental prosthesis (90), in particular all excess material of the prosthesis base (92) and the connecting element as well as the fixing key (21, 41) or remnants of the fixing key (21, 41) are removed.

14. Method according to one of the preceding claims, characterized in that after step G) the fixing key (21, 41) is removed, wherein preferably the dental prosthesis (90) is processed after step G) according to the virtual three-dimensional dental prosthesis model (1) by means of a subtractive CAM process and all excess material, in particular of the prosthesis base (92) and the fixing key (21, 41) or remnants of the fixing key (21, 41) are removed from the dental prosthesis (90).

15. Method according to one of the preceding claims, characterized in that the support structure (32) consists of a PMMA or a ceramic or of a combination of a PMMA or a ceramic with a metallic material, wherein preferably the metallic material is exposed on a basal side of the support structure (32) or is embedded in the PMMA or the ceramic.

16. Method according to one of the preceding claims, characterized in that additional bridge structures or reinforcement structures are provided when calculating the virtual model of the support structure in step B) and when manufacturing the support structure (32) in step E) and / or fastening means are provided for attaching the dental prosthesis (90) to teeth or implant abutments.

17. Method according to one of the preceding claims, characterized in that an excess is provided when calculating the virtual model of the support structure in step B) and when manufacturing the support structure (32) in step E), in particular an excess of 0.1 to 1 mm, which is removed in the area of ​​the connection to the denture base (92) or to the remaining denture base before step G) according to a connection surface between the support structure (32) and the tooth shells (28, 58, 95) on the one hand and the denture base (92) or the remaining denture base on the other hand using a subtractive CAM method and / or is removed in the areas protruding after step G) in comparison with the virtual three-dimensional dental prosthesis model (1) using a subtractive CAM method.

18. Method according to one of the preceding claims, characterized in that, when calculating the virtual model of the support structure in step B) and when manufacturing the support structure (32) in step E), a basal excess is provided on the basal side of the support structure (32), in particular an excess of 10 pm to 120 pm, wherein the basal excess is preferably provided in the area of ​​the connection to the prosthesis base (92) or to the remaining prosthesis base before step G) according to a connection surface between the support structure (32) and the Tooth shells (28, 58, 95) on the one hand and the denture base (92) or the remaining denture base on the other hand are removed using a subtractive CAM procedure.

19. Method according to one of the preceding claims, characterized in that the fixing key (21, 41) is provided with walls (18, 48) projecting in a basal direction, or before step G) walls (18, 48) are connected to the fixing key (21, 41) so that the walls (18, 48) project in a basal direction, wherein in step G) for the production of the denture base (92) or the remaining denture base, a polymerizable plastic is filled into the cavity (14, 44) laterally bounded by the walls (18, 48) onto the basal end of the support structure (32), is cured or partially cured there, and subsequently, using a subtractive CAM process according to the virtual three-dimensional dental prosthesis model (1), the denture base (92) is manufactured from the cured or partially cured polymerizable plastic, or parts of the denture base (92) are made from manufactured from cured or partially cured polymerizable plastic.

20. Method according to one of the preceding claims, characterized in that the support structure (32) in step E) is produced by laser sintering from a ceramic powder, in particular from a zirconium oxide ceramic powder.

21. Method according to one of the preceding claims, characterized in that the virtual model of the support structure is generated in step B) with a lattice structure, undercuts and / or cavities, wherein in step G) the material for the denture base (92) or the remaining denture base or an adhesive for connecting the denture base (92) or the remaining denture base with the support structure (32) and the tooth shells (28, 58, 95) penetrates the lattice structure, undercuts and / or cavities and thereby creates a mechanically stable connection between the denture base (92) or the remaining denture base and the support structure (32).

22. Method according to one of the preceding claims, characterized in that at least one functional element accessible from the basal side of the dental prosthesis (90) is attached to the support structure (32), wherein preferably the functional element is a bar or a matrix and / or the support structure (32) has a recess for receiving the at least one functional element.

23. Method according to one of the preceding claims, characterized in that the locking key (21, 41) is produced in step C) from a milling body (11, 22) which has a circumferential outer geometry (13, 23, 43) open on one or both sides and made of a dimensionally stable material and has an inner region made of an elastically deformable material, wherein in step C) the locking key (21, 41) is milled out of the inner region, wherein preferably the outer geometry (13, 23, 43) has retentions or a grid structure on its inner side to improve the mechanical connection to the inner region and / or the outer geometry (13, 23, 43) encloses the inner region in the form of a cylindrical tube section and the inner region is a cylindrical disk which is positively encompassed by the outer geometry (13, 23, 43).

24. Method according to one of the preceding claims, characterized in that all inwardly facing surfaces of the virtual model of the fixing key in step A) are calculated as a negative shape of vestibular surfaces of the virtual three-dimensional dental prosthesis model (1) or a virtual dental prosthesis outer contour of the virtual three-dimensional dental prosthesis model (1).

25. Method according to one of the preceding claims, characterized in that in step C) the fixing key (21, 41) is manufactured from a milling body (11, 22) with a holding geometry (20, 50) for fixing in a CAM device, wherein the holding geometry (20, 50) remains firmly connected to the fixing key (21, 41) and the fixing key (21, 41) with the tooth shells (28, 58, 95) and the support structure (32) is fixed via the holding geometry (20, 50) in a CAM device for machining by means of subtractive CAM methods and the tooth shells (28, 58, 95) and / or the support structure (32) are machined by a CAM method, while the tooth shells (28, 58, 95) and the support structure (32) are in the fixing key (21, 41) are held, preferably the holding geometry (20, 50) having an outer ring which is firmly and positively connected to the remaining milling body (11, 22) or the remaining fixing key (21, 41), and the holding geometry (20,50) has at least one fastening element on the outside for fixing the milling body (11, 22) or the fixing key (21, 41) in the CAM device.

26. Dental prosthesis (90) comprising a prosthesis base (92) and several prosthesis teeth (94), characterized in that The dental prosthesis (90) comprises a support structure (32) and tooth shells (28, 58, 95), wherein the tooth shells (28, 58, 95) are parts of the prosthesis teeth (94) and form an outer surface of the prosthesis teeth (94), wherein the support structure (32) forms a partial volume of the dental prosthesis (90), wherein the partial volume of the support structure (32) comprises at least one tooth partial volume of several of the prosthesis teeth (94) of the dental prosthesis (90), wherein the at least one tooth partial volume is spaced apart from the outer surfaces of the prosthesis teeth (94) or from partial areas of the outer surfaces of the prosthesis teeth (94), and wherein each of the at least one tooth partial volume of the support structure (32) connects several of the prosthesis teeth (94) of the dental prosthesis (90) in one piece, wherein the support structure (32) and the tooth shells (28, 58, 95) are connected flush to each other via a connecting element, wherein the tooth shells (28, 58,95) the remaining denture teeth not consisting of the support structure (32) and the connecting element, wherein the denture base (92) or the remaining denture base not formed by the support structure (32) is firmly and flush connected to the support structure (32) or to the support structure (32) and one or more or all of the tooth shells (28, 58, 95).

27. Dental prosthesis (90) according to claim 26, characterized in that the dental prosthesis (90) is manufactured using a method according to any one of claims 1 to 25.

28. Dental prosthesis (90) according to one of claims 26 or 27, characterized in that the connecting agent fills the space between the support structure (32) and the tooth shells (28, 58, 95) and / or the connecting agent is a cured adhesive, a cured plastic or a cured PMMA.

29. Dental prosthesis (90) according to one of claims 26 to 28, characterized in that the support structure (32) comprises several separate support structure parts, each of which has its own contiguous partial volume of the dental prosthesis (90) that is separate from the other partial volumes of the other support structure parts, wherein preferably the partial volumes of the support structure parts each comprise a contiguous tooth partial volume of several prosthesis teeth (94), in particular of several adjacent prosthesis teeth (94), wherein the tooth partial volumes are separated from the outer surfaces of the prosthesis teeth (94) are spaced apart or are from parts of the outer surfaces of the prosthetic teeth (94) and wherein several tooth part volumes of several prosthetic teeth (94) of the same part volume are connected in one piece.

30. Dental prosthesis (90) according to one of claims 26 to 29, characterized in that the tooth shells (28, 58, 95) and the support structure (32) are made of different materials, wherein preferably the support structure (32) is made of at least one material with a higher flexural strength than the material of the tooth shells (28, 58, 95) and / or of at least one material with a flexural strength of at least 3000 MPa / Nm 3 consists.

31. Dental prosthesis (90) according to one of claims 26 to 30, characterized in that the support structure (32) consists of a plastic, a PMMA and / or a ceramic or of a combination of a plastic, a PMMA or a ceramic with a metallic material, wherein preferably the metallic material is exposed on a basal side of the support structure (32) or is embedded in the plastic, in which the PMMA or in the ceramic is embedded.

32. Dental prosthesis (90) according to one of claims 26 to 31, characterized in that the support structure (32) may include additional bar structures or reinforcement structures and / or fastening means for attaching the dental prosthesis (90) to teeth or implant abutments.

33. Dental prosthesis (90) according to one of claims 26 to 32, characterized in that the support structure (32) has a lattice structure, undercuts and / or cavities, wherein the material of the denture base (92) or the remaining denture base or a connecting means for connecting the denture base (92) or the remaining denture base to the support structure (32) and / or the tooth shells (28, 58, 95) partially or completely fills the lattice structure, undercuts and / or cavities.

34. Dental prosthesis (90) according to one of claims 26 to 33, characterized in that the dental prosthesis (90) has a fixing key (21, 41) that is flush with or glued to the outer surfaces of the prosthesis teeth (94).

35. Device or combination of devices for carrying out a method according to any one of claims 1 to 25, comprising a CAM device and a computer programmed for calculating the virtual models and for controlling the CAM device according to any one of claims 1 to 25.

36. Device according to claim 35, the device characterized by a fixing key surface calculation module for calculating the first surface of the virtual model of the fixing key according to step A); and a fixing key control module for a CAM device, in particular for a subtractive CAM device, programmed to control the subtractive production of the surfaces calculated with the fixing key surface calculation module in a milling body (11, 22); a support structure calculation module for calculating the outer shape of the support structure according to step B); and a support structure control module for a CAM device, in particular for an additive CAM device, programmed to control the production of the support structure calculated with the support structure calculation module (32); and preferably a machining control module for a CAM device programmed to control the subtractive machining of the basal side of the tooth shells (28, 58, 95) inserted into the fixing key (21, 41) and the support structure (32) according to a joining surface (34), which is particularly preferably calculable with a joining surface calculation module of the device.

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