METHOD FOR PRODUCING A COMPUTER MODEL FOR AN ABUTMENT AND AN ABUTMENT

Description

[0001] The invention relates to a method having the features of the preamble of claim 1 and / or claim 2 and a method for producing an abutment as well as a computer program product, a computer-readable storage medium, a computer-readable data carrier and a data carrier signal which transmits such a computer program product and a computer which is configured to carry out one of the methods and / or to execute such a computer program product.

[0002] In dentistry, an abutment (sometimes referred to as an "attachment") is the connecting element between a post-shaped dental implant and a prosthetic restoration (e.g., a single-tooth restoration, a bridge restoration, a denture, etc.). The connection to the prosthetic restoration can be made directly or via a mesostructure.

[0003] An abutment is disclosed in EP 2 825 124 B1. The abutment shown in this document features a platform with a plate-like configuration of the coronally facing platform surface, which promotes cell growth and allows support of a mesostructure or a prosthetic restoration on the coronally facing platform surface. The possibility of subsequent processing of the abutment allows for customization of the abutment for a specific patient.

[0004] US 2013 / 189646 A1, US 2012 / 072178 A1 and EP 2 204 138 B1 are cited as relevant prior art.

[0005] In dental implantology, an emergence profile is the three-dimensional course of the gum where the abutment is to be placed, in a coronally running area starting from the dental implant to the gum line.

[0006] In addition to prefabricated standard abutments, which require laborious manual reworking in the dental laboratory to adapt them to the specific conditions at the restoration site in the patient's jaw, it is already known to produce directly patient-specific abutments. This is done using a computer-readable three-dimensional computer model of the patient-specific abutment to be manufactured. The three-dimensional computer model is either created based on an analog jaw impression of the patient's jaw, which is then digitized, or provided directly in digital form (e.g., using an intraoral scanner or laboratory scanner).

[0007] An operator (e.g. dental technician or dentist) or an algorithm defines the patient's individual gum line where the abutment is to be placed.

[0008] The operator or an algorithm must also define the three-dimensional geometry of the abutment above a preparation margin determined by the individual gingival contour. The definition of the three-dimensional geometry of the abutment can include: Definition of the position of a screw channel running through the abutment for attaching the abutment to a post-shaped dental implant. The position is usually defined relative to the orientation of the post-shaped dental implant. Definition of the width of a coronally facing platform surface of the abutment. Definition of the height of the abutment. Definition of the width of a central elevation of the abutment containing the screw channel.

[0009] In addition, the emergence profile of the abutment must be defined by a computer operator or by an algorithm.

[0010] The emergence profile, i.e. the external geometry of the abutment below the preparation margin up to the post-shaped dental implant, was previously specified with a standard shape, and the area between the emergence profile and the screw channel was defined as a solid body, leaving the computer operator no room for maneuver here. As a result, in practice, a preparation margin that was inherently too deep was often selected in order to enlarge the area that could be selected or defined by the operator or the algorithm. This entails the problem that the so-called adhesive joint between the abutment and the prosthetic restoration shifts towards the dental implant and thus the patient's jawbone, which has destructive consequences for the gums and jawbone.

[0011] The object of the invention is to provide a method for producing a three-dimensional computer model of a patient-specific abutment for a dental implant by means of a computer and a method for producing such an abutment for a dental implant, in which the computer model or the abutment produced according to it is better compatible with the patient's gums and jawbone.

[0012] This object is achieved by a method having the features of claim 1 and / or claim 2 and by a method having the features of claim 7.

[0013] Furthermore, the invention is intended to provide a computer program product comprising instructions for carrying out the method, a computer-readable storage medium and a computer-readable data carrier comprising such instructions as well as a data carrier signal which transmits such a computer program product, and a computer for carrying out one of the methods according to the invention and / or for executing the computer program product according to the invention.

[0014] This object is achieved by a computer program product having the features of claim 8, a computer-readable storage medium having the features of claim 9, a computer-readable data carrier having the features of claim 10, a data carrier signal having the features of claim 11 and a computer having the features of claim 12.

[0015] The steps of the method according to the invention are carried out outside a patient's body, since the invention is based on an already existing three-dimensional representation of a patient's jaw, at least in that region of the jaw where the abutment is to be placed.

[0016] Advantageous embodiments of the invention are defined in the dependent claims.

[0017] According to a first variant of the invention, a plate-like design of the coronally facing platform surface is provided below the preparation margin for the three-dimensional geometry of the platform, as is known per se from EP 2 825 124 B1. The plate-like design has an adhesive joint between the abutment and the prosthetic restoration that is advantageously located far away from the dental implant. Because it is further provided that a computer operator selects a material thickness for the abutment platform based on the defined emergence profile, i.e. below the preparation margin, the computer operator is no longer required to select a preparation margin that is too deep in order to increase his design freedom, since the invention allows the operator to design the three-dimensional geometry of the abutment below the preparation margin from the outset.In order to avoid disadvantageous designs that could lead to failure of an abutment produced according to the three-dimensional computer model provided by the computer, the invention provides that the three-dimensional geometry of the abutment below the preparation limit can only be selected by the operator within a predetermined range stored in an electronic memory.

[0018] In principle, a plate-like configuration of the coronally facing platform surface alone would be sufficient. However, a curved underside of the platform (the surface of the platform spaced from the coronally facing platform surface by the material thickness) is also preferred.

[0019] The invention provides that the three-dimensional geometry of the abutment below the preparation margin can be selected by the operator at least to the extent that the operator can select a material thickness of the platform of the abutment (ie the normal distance between the coronally facing platform surface and the platform surface facing away from it) based on the defined emergence profile.

[0020] In preferred embodiments, the invention provides that the three-dimensional geometry of the abutment below the preparation margin can be further selected by the operator to the extent that an operator of the computer a material thickness of a wall of the screw channel (i.e. the normal distance between the inner wall defining the screw channel and a wall facing away from this of the coronally extending region of the abutment having the screw channel) and / or a material thickness of the base of the abutment (i.e. the normal distance between the outer side of the abutment facing the connecting structure and the coronally facing platform surface) and / or for the transition between the coronally facing platform surface and the base of the abutment and / or for the transition between the base of the abutment and a wall of the screw channel a transition radius is selected within a predefined range stored in an electronic memory.

[0021] It should be noted that constant material thicknesses are preferred for the material thickness of the abutment platform and / or the material thickness of the screw channel wall and / or the material thickness of the abutment base. However, a gradient for one or more of these material thicknesses (variable material thickness) would also be possible. The gradient can be defined by specifying one or more support points.

[0022] Preferably, the respective area for the possible selection of the material thickness or for the transition radius is selected depending on the material to be used for the abutment (e.g. ceramic, titanium, plastic or hybrid materials) and / or depending on the defined three-dimensional geometry of the abutment above the preparation limit.

[0023] The predetermined range stored in an electronic memory (to which the computer must, of course, have access during the execution of the process, at least during the corresponding step) can be determined on the basis of empirical values ​​and / or simulations and / or series of measurements. For example, it can be provided that the material thickness the base of the abutment can be selected in a range from approximately 0.05 mm to approximately 4 mm the platform can be selected in a range from approximately 0.05 mm to approximately 2 mm the wall of the screw channel can be selected in a range from approximately 0.05 mm to approximately 3 mm

[0024] It is preferably provided that the method and a corresponding computer program, which, when the program is executed by a computer, causes the computer to carry out the method, directly create a three-dimensional computer model for an abutment with a plate-like, coronally facing platform surface, based on a provided three-dimensional representation of a patient's jaw that can be read by the computer.

[0025] Alternatively, however, in a second variant of the invention, it can be provided that, using a conventional method and a corresponding computer program, a three-dimensional starting computer model of a patient-specific abutment is first created, which has a shape such that an area extending radially between the screw channel of the abutment and the emergence profile of the abutment is shown as filled with material.The computer then performs a transformation according to the method of the invention or with a corresponding computer program of the invention to obtain the three-dimensional computer model from the three-dimensional starting computer model, in which a plate-like configuration of the coronally facing platform surface is provided below the preparation limit for the three-dimensional geometry of the platform, and which has the material thickness of the abutment platform selected by a computer operator based on the defined emergence profile. The same additional optional features can be provided as discussed with reference to the first variant of the invention.

[0026] For the production of an abutment according to the invention for a dental implant using a material-reduced three-dimensional computer model of the patient-individualized abutment produced by a method according to at least one of the preceding embodiments, an additive manufacturing process (e.g. laser sintering) is preferably proposed, in which powder (e.g. made of ceramic, titanium, plastic or hybrid materials) is solidified layer by layer by the action of energy.

[0027] Compared to conventional machining or cutting processes for producing an abutment, additive manufacturing processes are characterized by a shorter process time. Furthermore, machining or cutting processes often require complex reclamping. Even when using an additive manufacturing process, machining or cutting post-processing may be necessary.

[0028] In all embodiments, the screw channel can run parallel to or at an angle to a central imaginary axis of the connecting structure of the abutment.

[0029] Embodiments of the invention are discussed with reference to the figures. They show: Fig. 1a,b schematic representations of two variants of an arrangement for carrying out the method according to the invention Fig. 2 a schematic representation of a manufacturing process of an abutment using the result of the method of Fig. 1a oder 1b Fig. 3a-d different views and a sectional view of an embodiment of an abutment to be produced by the invention Fig. 4 a sectional view as in Fig. 3d with dimensioning of the material thicknesses Fig. 5a-d various views and a sectional view of an embodiment of a three-dimensional starting computer model of a patient-specific abutment, which is transformed in the course of the method according to the invention Fig. 6 a sectional view through an embodiment of an abutment to be produced by the invention, wherein it can be seen how the transformation was carried out starting from a three-dimensional starting computer model in the second variant of the invention Fig. 7a-d representation of a computer-readable three-dimensional representation of a patient's jaw with a computer model of an abutment or without the abutment, a gingival mask and an abutment produced according to the method according to the invention with a prosthetic restoration in the form of a crown

[0030] Fig. 1a shows schematically an arrangement for operating a method for producing a three-dimensional computer model 1 of a patient-specific abutment 2 for a dental implant 12 by means of a computer 3, wherein the abutment 2 (cf. Fig. 3a-d ) has: a base 4 a connection structure 5 for connecting the abutment 2 to a pin-shaped dental implant 12 (cf. Fig. 7b ) a coronally facing platform surface 6 of a platform of the abutment 2 for supporting a prosthetic restoration and a screw channel 7 for attaching the abutment 2 to a pin-shaped dental implant 12

[0031] A central imaginary axis Z of the connecting structure 5 of the abutment 2 can be seen.

[0032] A three-dimensional representation 10 of the patient's jaw, readable by the computer 3, is provided, at least in that region of the jaw where the abutment 2 is to be placed. This three-dimensional representation can be provided in a known manner either on the basis of an analog jaw impression of the patient's jaw, which is digitized, or directly in digital form (e.g., using an intraoral scanner and / or a laboratory scanner).

[0033] In a known manner, a definition of a preparation margin is selected depending on the patient's individual gingival contour where the abutment 2 is to be placed, by an operator of the computer 3 or by an algorithm.

[0034] A three-dimensional geometry of the abutment 2 above the preparation margin is defined by an operator of the computer 3 or by an algorithm. The definition of the three-dimensional geometry of the abutment 2 can include: Definition of a position of the screw channel 7 running through the abutment 2 for attaching the abutment 2 to a post-shaped dental implant 12. The position is usually defined relative to an orientation of the post-shaped dental implant 12. Definition of a width of a coronally facing platform surface 6 of the abutment 2. Definition of a height of the abutment 2. Definition of a width of a central elevation of the abutment 2 containing the screw channel 7.

[0035] The emergence profile E of the abutment 2 is defined by an operator of the computer 3 or by an algorithm.

[0036] According to the invention, a plate-like design of the coronally facing platform surface 6 is provided below the preparation limit for the three-dimensional geometry of the platform.

[0037] Based on the defined emergence profile E, an operator of the computer 3 selects within predetermined ranges stored in an electronic memory 8 (cf. Fig. 4 and 6 ): a material thickness d 1 of the platform of the abutment 2, a material thickness d 2 of the base 4 of the abutment 2 and / or a material thickness d 3 of a wall of the screw channel 7 and / or a transition radius R 1 for the transition between the coronally facing platform surface 6 and the base 4 of the abutment 2, a transition radius R 2 for the transition between the base 4 of the abutment 2 and a wall of the screw channel 7

[0038] The three-dimensional computer model 1 is provided by the computer 3, for example for producing a patient-specific abutment 2 for a dental implant 12 using a three-dimensional computer model 1 produced according to the method just described, preferably by an additive manufacturing process.

[0039] The embodiment of the Fig. 1b differs from the previously discussed embodiment only in that, according to the second variant of the invention, a three-dimensional start computer model 9 of a patient-specific abutment 2 is first created depending on the provided three-dimensional representation of the jaw, the definition of the emergence profile E and the three-dimensional geometry of the abutment 2 above the preparation limit, wherein the three-dimensional start computer model 9 has a shape such that an area extending radially between the screw channel 10 of the abutment 2 and the emergence profile E of the abutment 2 is shown as filled with material (cf. Fig. 5a-d ). Starting from this three-dimensional starting computer model 9 (which in itself represents a functional abutment), the computer 3 performs a transformation using an algorithm (the algorithm calculates, for example, a certain necessary material thickness depending on the angle of the screw channel and the calculated load peaks) in order to obtain the three-dimensional computer model 1 from the three-dimensional starting computer model 9, in which a plate-like formation of the coronally facing platform surface 6 is provided below the preparation limit for the three-dimensional geometry of the platform and which has the material thickness d 1 of the platform of the abutment 2 selected by an operator of the computer 3 based on the defined emergence profile E and the other discussed parameters. In Fig. 6 An example is shown of which area shown as filled with material (dotted area) is to be removed during the transformation.

[0040] Fig. 7a shows a representation of a three-dimensional representation 10 of a patient's jaw, readable by the computer 3, with a three-dimensional computer model 1 of a patient-specific abutment 2.

[0041] In Fig. 7b was that in Fig. 7a The abutment 2 shown is removed, allowing a view of the upper region of a pin-shaped dental implant 12. The abutment 2 with its connecting structure 5 is inserted into this upper region of the pin-shaped dental implant 12. Fig. 7c shows a gingival mask (which in Fig. 7a und 7b however, is not provided for).

[0042] Fig. 7d shows an abutment 2 produced according to the method according to the invention with a prosthetic restoration in the form of a crown. List of reference symbols:

[0043] 1 Three-dimensional computer model of a patient-specific abutment 2 Abutment 3 Computer 4 Abutment base 5 Connection structure 6 Coronal-facing platform surface 7 Screw channel 8 Electronic memory 9 Three-dimensional start computer model of a patient-specific abutment 10 Three-dimensional representation of a patient's jaw 11 Manufacturing system 12 Dental implant EEmergence profile of the abutment Zcentral imaginary axis of the connecting structure of the abutment d 1 Material thickness of the platform of the abutment d 2 Material thickness of the base of the abutment d 3 Material thickness of a wall of the screw channel of the abutment R 1 Transition radius of a transition between the coronally facing platform surface and the base of the abutment R 2 Transition radius of a transition between the base of the abutment and a wall of the screw channel

Claims

1. A method of producing a three-dimensional computer model (1) of a patient-individual abutment (2) for a dental implant (12) specific for a patient by means of a computer (3), wherein the abutment (2) has at least a base (4), a connecting structure (5) for connecting the abutment (2) to a pin-shaped dental implant (12), a coronally looking platform surface (6) of a platform of the abutment (2) for supporting a prosthetic fitting and a screw passage (7) for fixing the abutment (2) to a pin-shaped dental implant (12), comprising at least the following steps: - providing a three-dimensional representation (10) of a jaw of the patient readable by the computer (3), at least in that region of the jaw where the abutment (2) is to be placed, - selecting a definition of a preparation limit in dependence on a gum line individual for the patient where the abutment (2) is to be placed, by an operator of the computer (3) or by an algorithm, - defining a three-dimensional geometry of the abutment (2) above the preparation limit by an operator of the computer (3) or by an algorithm, - defining an emergence profile (E) of the abutment (2) by an operator of the computer (3) or by an algorithm, and - providing the three-dimensional computer model (1) by the computer (3), characterised in that provided below the preparation limit for the three-dimensional geometry of the platform is a plate-like configuration of the coronally looking platform surface (6) and a material thickness (d1) of the platform of the abutment (2) is selected by an operator of the computer (3) starting from the defined emergence profile (E) within a predetermined range stored in an electronic memory (8).

2. A method of producing a three-dimensional computer model (1) of a patient-individual abutment (2) for a dental implant (12) specific for a patient by means of a computer (3), wherein the three-dimensional start computer model (9) represents an abutment which has a base (4), a connecting structure (5) for connecting the abutment (2) to a pin-shaped dental implant (12), a coronally looking platform surface (6) of a platform of the abutment (2) for supporting a prosthetic fitting and a screw passage (7) for fixing the abutment (2) to a pin-shaped dental implant (12), characterised by at least the following steps: - providing a three-dimensional start computer model (9) of the patient-individual abutment (2), wherein the three-dimensional start computer model (9) is of such a form that a region extending radially between the screw passage (10) of the abutment (2) and the emergence profile (E) of the abutment (2) is represented as filled with material, - carrying out a transformation by means of the computer (3) in order to obtain from the three-dimensional start computer model (9) a three-dimensional computer model (1) in which a plate-like configuration of the coronally looking platform surface (6) is provided below the preparation limit for the three-dimensional geometry of the platform and which has a material thickness (d1) of the platform of the abutment (2) that is selected by an operator of the computer (3) starting from the defined emergence profile (E) within a predetermined range stored in an electronic memory (8).

3. A method as set forth in one of the two preceding claims wherein further a material thickness (d3) of a wall of the screw passage (7) is selected by an operator of the computer (3)within a predetermined region stored in an electronic memory (8).

4. A method as set forth in one of the preceding claims wherein a material thickness (d2) of the base (4) of the abutment (2) is selected by an operator of the computer (3) within a predetermined range stored in an electronic memory (8).

5. A method as set forth in at least one of the preceding claims wherein a transition radius (R1, R2) within a predetermined region stored in an electronic memory (8) is selected - for the transition between the coronally looking platform surface (6) and the base (4) of the abutment (2), and / or - for the transition between the base (4) of the abutment (2) and a wall of the screw passage (7).

6. A method as set forth in at least one of the preceding claims wherein the respective range for the possible selection of the material thickness (d1, d2, d3) or for the transition radius (R1, R2), respectively, is selected in dependence on a material to be used for the abutment (2) and / or in dependence on the defined three-dimensional geometry of the abutment (2) above the preparation limit.

7. A method of producing a patient-individual abutment (2) for a dental implant (12) using a three-dimensional computer model (1) produced in accordance with a method as set forth in one of the preceding claims, preferably by an additive production method.

8. A computer program product comprising commands which when the program is executed by a computer (4) cause it to carry out the method as set forth in at least one of claims 1 through 6.

9. A computer-readable storage medium comprising commands which when executed by a computer (4) cause it to carry out the method as set forth in at least one of claims 1 through 6.

10. A computer-readable data carrier on which the computer program product as set forth in claim 8 is stored.

11. A data carrier signal which transmits the computer program product as set forth in claim 8.

12. A computer configured to carry out a method as set forth in at least one of claims 1 through 7 and / or for executing a computer program product as set forth in claim 8.