Method for establishing a connection between a number of inserted dental implants and a prosthetic body

Abstract

The aim of the invention is to devise a method for providing a connection between a number of inserted dental implants and a prosthetic body, which makes it particularly simple to establish a reliable and secure connection between the prosthetic body and the inserted implants. For this purpose, according to the invention, the prosthetic body is provided with a recess for each dental implant, said recess being associated with the dental implant and being suitable for accommodating a connecting element of the particular dental implant. Following the insertion of the dental implants into the jawbone of the patient, the intraoral data characteristic of the oral situation of the patient including the inserted dental implants is captured. Using this intraoral data, the geometric data defining the intermediate space formed by the connecting element and the associated recess when the prosthetic body is correctly placed is determined for the connecting element of the dental implant, and, using this data, an intermediate body is produced that fills the intermediate space.

Description

[0001] Description

[0002] Method for creating a connection between a number of inserted dental implants and a prosthetic body

[0003] The invention relates to a method for producing a connection between a number of dental implants inserted in a patient's mouth and a prosthetic system. It further relates to a method for producing a connecting piece, in particular for use with such a prosthetic system.

[0004] In the event of tooth loss, the usual aim is to replace the missing teeth or at least close the resulting gaps. This can be achieved, for example, with bridges. In this process, the teeth adjacent to the gap are prepared (ground down), and crowns are fabricated to replace the missing teeth with corresponding pontics (bridge units). The bridge is mechanically anchored to the prepared teeth. A cantilever can also be attached to a bridge to address a free-end situation. Such a situation can also be treated with removable partial dentures, which are typically supported by natural teeth.

[0005] In addition to bridges, missing teeth can also be replaced using e-nosseous implants. These typically use threaded posts as artificial tooth roots, onto which the prosthesis can be anchored.

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

[0007] As soon as too few teeth remain in the patient's mouth, other solutions are usually employed. One option is to remove all remaining teeth and use mucosa-supported dentures. These are inexpensive, but offer poor chewing comfort for the patient and are often accompanied by bone loss in the upper and lower jaw. Frequently, the remaining teeth and / or endosseous implants are used as abutments for a full denture or a denture covering a relatively large portion of the dentition. For example, in a so-called "all-on-four" concept, a number of, say, four inserted dental implants can be used as abutments to which the prosthetic body is attached.This requires a suitable connection system that allows the inserted dental implants to be securely and reliably connected to the prosthetic restoration, also with regard to the expected forces and loads, such as chewing forces.

[0008] In particular, when providing such a restoration based on an "all-on-four" concept (or, of course, analogously for any other number of abutments), so-called "navigated implantation" can be used. With such navigated implantation, for example, for use with the "all-on-four" concept, but not limited to it, the intended implant positions in the patient's jaw are first planned virtually using previously acquired CBCT or CT data depicting the patient's oral situation, with regard to the planned use of implants inserted into the patient's jawbone as abutments for the restoration.Based on this planning, a template (usually bone-supported, mucosa-supported or tooth-supported) is created for the actual navigated implantation, and a temporary prosthesis is produced as a temporary dental prosthesis, so that the patient can be provided with fixed teeth on the day of the operation or insertion of the implants.

[0009] The template is used to guide the drill holes in the jawbone for the implants and to define their final position. In a subsequent step, the implants are inserted through this template, ensuring they are automatically placed in the correct positions corresponding to the previously drilled holes.

[0010] Typically, immediately following implant placement, a conventional or digital impression is taken to capture the patient's oral situation, also known as an "impression." This is done at the level of the implants or the implant abutments. Based on this precise data, accurately reflecting the oral situation including the implants, the final dental prosthesis or denture can be planned and fabricated. After this data capture, the temporary prosthesis is attached to the implants on the same day, specifically by screwing it in place. For this, the special temporary abutments are first screwed onto the "All-on-4" abutments.

[0011] During the fabrication of the temporary prosthesis, suitable recesses or cavities are provided at the positions intended for connection to the supporting abutments or implants, particularly the implant heads. Appropriate connecting elements for attachment to the implant heads or abutments can be inserted into these recesses or cavities. These recesses or cavities of the temporary prosthesis are then filled with a resin adhesive, modeling resin, cement, or similar material and fixed to the temporary abutments using this material. The connection between the inserted dental implants and the temporary prosthesis body is thus established as a material-bonded connection.

[0012] In light of the inaccuracies typically encountered during data acquisition and processing, as well as the almost unavoidable manufacturing and implant insertion tolerances, the recesses or cavities are made comparatively large and generally oversized. This is done, not least, to give the clinician sufficient freedom for fine-tuning and precise adjustment when placing the provisional prosthesis. However, this approach also presents problems and disadvantages, as a relatively large amount of adhesive or cement is required to adequately fill the cavities, resulting in a comparatively large amount of excess adhesive or cement that needs to be removed during placement. Furthermore, this makes precise alignment of the prosthesis in the mouth over the provisional abutments comparatively difficult.

[0013] The invention is therefore based on the objective of providing a method for establishing a connection between a number of inserted dental implants and a prosthetic body of the type mentioned above, with which a reliable and secure connection of the prosthetic body with the inserted implants can be achieved in a particularly simple manner, especially with regard to precise (rotational) alignment.This problem is solved according to the invention by providing the prosthetic body for each dental implant with a recess assigned to it, suitable for receiving a connecting element of the respective dental implant, wherein, after the insertion of the dental implants into the patient's jawbone, the intraoral data characteristic of the patient's oral situation, including the inserted dental implants, are recorded, wherein, based on these intraoral data, the geometric data defining the space formed by the connecting element and the assigned recess when the prosthetic body is correctly placed are determined for the connecting element of the respective dental implant, and an intermediate body filling the space is manufactured based on these data.

[0014] The invention is based on the premise that a significant simplification in providing the connection between inserted implants and prosthetic restorations can be achieved by specifically reducing the material used to create the bond (adhesive bonding or cementation) and the resulting, inherently undesirable, excess material. To this end, based on known geometric information, the necessarily resulting gap between the connecting element of the respective implant and the corresponding recess in the prosthetic body should be filled as completely as possible with a provided filler. This filler should be manufactured as precisely as possible, based on the determined actual data, so that the amount of material required to fill any remaining gaps can be minimized.

[0015] In an alternative variant, considered to be independently inventive, instead of producing an intermediate or filler body that fills the gap as much as possible or almost completely, a positioning framework body can also be provided. This framework body can be designed, particularly with regard to its contouring and / or surface finish, such that contact with the surrounding components is established in the assembled system, thereby ensuring the precise and correct orientation and spatial positioning of these components relative to one another. Such a positioning framework body, provided according to this aspect of the invention, thus ensures the correct positioning of the components, and the gaps left behind by this framework-like body can be filled with adhesive or cement during installation or integration.Advantageously, the positioning scaffold body can be provided with a channel, preferably designed in the form of an internally or externally attached thread, through which excess adhesive or cement material can flow off or be carried away.

[0016] If the intermediate body, and in this specific case the positioning framework body, is manufactured using an additive manufacturing process (3D printing, laser sintering, etc.), the manufacturing time for the positioning framework body is significantly reduced compared to the manufacturing of the entire framework body. Preferably, the positioning framework body fills less than 70%, advantageously less than 50%, and particularly less than 30% of the volume of the intermediate piece, so that the manufacturing time can be minimized accordingly.

[0017] For the sake of clarity, the following explanations refer to the intermediate body. Of course, the following further training and aspects can also be applied analogously to the aforementioned positioning framework body.

[0018] In an advantageous embodiment, analogous to the conventional process described above, the prosthetic body is manufactured as a provisional prosthesis, wherein the four recesses or cavities corresponding to the contact points (according to the "all-on-four" concept) each have a defined geometry, conceivable as a "matrix". A significant advantage of the present invention is that, even with the concept now provided, the prosthetic body can be manufactured in advance and provided as a prefabricated part during insertion. In an advantageous embodiment, the aforementioned geometry or shape can be designed such that the associated connecting element, conceivable as a "patrix" corresponding to the respective matrix, is defined as precisely as possible, advantageously in terms of both orientation and, if necessary,It can also be precisely fixed or attached in a unique position from a rotational perspective.

[0019] In principle, any dental implant could be designed as a so-called one-piece implant, in which the connecting element located at the abutment is integral with the post that is inserted or can be inserted into the patient's jawbone. However, to allow for greater flexibility in the configuration or manufacture of the components, the dental implant is advantageously designed as a so-called two-piece implant. In this case, the connecting element is a so-called abutment and can be attached to the inserted post of the implant via suitable connecting means, such as a connecting pin that can be inserted into a receiving channel. Therefore, such an abutment is preferably used as the connecting element.Alternatively, the actual implant can also be equipped with a so-called "All-on-Four" abutment for the purpose of connecting it to the final prosthetic body. However, for providing a temporary prosthesis—that is, a provisional prosthetic body that is later to be replaced by the final one—so-called "provisional abutments" can also be used as connecting elements. These can be (temporarily) attached to the actual "All-on-Four" abutments of the implants in the manner of an intermediate support, preferably screwed in place.

[0020] According to one aspect of the invention, the prosthetic body is thus screwed onto the actual “All on four” abutments of the implants via the secondary abutments after the intermediate pieces produced as described above have been glued into their respective cavities in the prosthetic body and bonded to the temporary or secondary abutments.

[0021] According to one aspect of the invention, after implant insertion and, if applicable, the mounting of the "all-on-four" abutments, the intraoral data are acquired as directly as possible, for example, by taking a digital impression or by taking a conventional impression and scanning the fabricated master model. Subsequently, the resulting data set, describing the current position of the implants within the oral cavity, can be superimposed with the data of the desired position of the implants in the mouth in order to capture the space between the prosthetic body—which, as explained above, has already been fabricated according to a particularly advantageous aspect—and the respective abutments or provisional abutments forming the connecting element.A significant advantage of the present invention is seen in the fact that, with the concept now envisaged, the prosthetic body can be manufactured in advance and provided as a pre-made part during the insertion.

[0022] Using suitable software, preferably computer software, the transitions from the respective abutment to the prosthetic body can be calculated and the gap determined. The data set characteristic of this gap can then be used as the basis for the subsequent fabrication of the intermediate piece or intermediate body for each of the aforementioned contact points. Thus, according to one aspect of the invention, the corresponding intermediate pieces can be fabricated for each of the individual abutment-recess connections, preferably four. Subsequently, the fabricated intermediate pieces can be unambiguously fixed in the matrices or recesses of the prosthesis, according to another aspect of the invention, also in a unambiguous rotational position, preferably by gluing or cementing. Finally, the abutments are fixed in the prosthesis, preferably by gluing or cementing.Of course, the intermediate pieces can also be fixed to the abutments first, and then these, including the intermediate pieces, can be fixed in the prosthesis.

[0023] Advantageously, the recesses associated with the dental implants each have different geometries. It is particularly preferred that the connecting element of each dental implant be manufactured with a geometry adapted to the geometry of its associated recess. This ensures a high degree of avoidance of confusion and unambiguous component identification throughout the entire process. In one embodiment and according to one aspect, this can be achieved, for example, by an individualized height offset. Alternatively or additionally, the recesses—preferably provided in the prosthesis body—can have a contour in cross-section that extends, particularly in the mesiodistal direction. This contour is preferably designed in a poka-yoke manner for each position to prevent confusion.In particular, the cross-sections can be contoured and dimensioned in such a way that incorrect insertion is rendered impossible due to their shape. This ensures that the individual components can be clearly identified and assigned at any time, even during the manufacturing process.

[0024] In a particularly advantageous embodiment, the contact points, preferably four but also two to eight, each formed by a combination of a connecting element of an implant on the one hand and a corresponding recess in the prosthetic body on the other, are designed such that the corresponding number of male components, preferably four, are not interchangeable, but rather there are preferably four (or possibly two to eight) unique female component geometries. Thus, the fabrication of each male component can be carried out in a manner precisely matching a specific female component, whereby subsequent placement or attachment can also be provided for in only one rotational position within the corresponding female component. The aforementioned provisional abutments are typically not restricted in their rotation on the "all-on-four" abutments.It is therefore also possible to place the uniqueness in the connection between the "all on four" abutment and the provisional abutment, or in the connection between the intermediate piece and the provisional abutment.

[0025] A particularly advantageous benefit achievable with the present method is that the connection between the connecting elements or abutments of the implants, on the one hand, and the prosthetic body, on the other, can be established with minimal effort and, in particular, relatively quickly. To further facilitate this, a particularly efficient and, above all, rapid production of the respective intermediate pieces or bodies is highly desirable. To enable these to be produced quickly and cost-effectively, each intermediate body can be manufactured using a 3D printing process, according to a concept considered to be independently inventive. This method of production with a 3D printer is particularly simple and economical, especially when dealing with a temporary prosthesis.If the prosthesis is a final prosthesis, it might be more advantageous to manufacture it from titanium, preferably by machining or additive manufacturing. Regarding the machining method, according to a further development, blanks could be used that already have the intended connection to the prosthesis, so that only the connection for the abutments needs to be manufactured, or vice versa.

[0026] In a particularly preferred embodiment, the (preferably temporary) abutments can be clamped into a 3D printer, which prints the space-filling intermediate pieces or bodies directly onto the abutments, allowing them to be fixed directly into the prosthesis. In other words, according to this aspect of the invention, the respective intermediate body can be printed directly onto the connecting element of the respective dental implant.

[0027] A printer suitable for such an application, considered to be independently inventive in this case, has, according to aspects of the invention, a rotary axis ("C-axis") which accommodates the abutment or connecting element to be printed. This rotary axis can also be moved in the axial direction ("X-axis"). To check the exact dimensions of the abutment or connecting element, this rotary axis can preferably be moved via the X-axis to a distance sensor (or a similar measuring instrument such as an optical micrometer). The component can be measured at the area to be printed via the rotation and the C-axis. According to one aspect of this independent invention, an additional Z-axis allows the print head (preferably designed as a print element or filament holder) of the 3D printer to be moved to the correct distance to apply the material, preferably plastic.

[0028] The actual printing element, in particular the so-called filament holder or similar component, should, according to a further aspect of the invention, be able to be moved up and down along a Z-axis (preferably oriented at a 90° angle to the X-axis). According to another aspect of the invention, the 3D printer can also have a pivoting axis ("B-axis") that can pivot the axis of rotation up to an angle of 90° to the X-axis. With a printer designed in this way, the intermediate piece can be printed directly onto the abutment, which significantly simplifies and speeds up the manufacturing process. In this way, the crown, as well as the intermediate piece with or without a screw channel, can be produced. It is possible that after printing the intermediate piece or the positioning framework, the abutment may need to be shortened in the occlusal direction.

[0029] In an alternative embodiment, also considered independently inventive, the respective connecting element or abutment can be provided in the form of a blank or intermediate product for subsequent machining, wherein such a blank can comprise a base body made of a biocompatible, high-strength material, preferably titanium or a titanium alloy, which is additionally provided with a plastic coating. This coating can then be machined away according to one aspect of the invention in such a way that the remaining plastic coating constitutes the aforementioned intermediate body and thus appropriately fills the gap determined by the data.

[0030] According to another aspect considered to be independently inventive, the method can be used in conjunction with training or education for the practitioner. In this context, the invention allows the practitioner to draw conclusions about the quality of their insertion procedure, as well as the components and tools used, based on information about the dimensions of the aforementioned gaps or the wall thicknesses and dimensions of the spacers to be manufactured for filling them. In particular, this makes it possible to obtain information regarding the (individual or objective) accuracy and precision of the navigated implantation.Especially when systematically comparing relevant quality indicators or statements derived from them over a certain period or a certain number of treatments, the practitioner can also gain insights in the form of feedback.

[0031] If such an evaluation reveals that the dentist has succeeded in improving this precision over time or through multiple treatments, resulting in increasingly smaller or thinner-walled intermediate pieces, it becomes possible, after a certain period, to completely dispense with the temporary prosthesis and fabricate the final prosthetic body in advance. This final prosthesis, along with the fabricated intermediate pieces, could then be inserted into the patient's mouth on the day of implantation. This would significantly and sustainably reduce the costs of such treatment.

[0032] To enable such systematic information processing, according to one aspect of the invention and in a particularly advantageous embodiment, the geometric data defining the gaps can be stored in a database. According to another aspect of the invention, a characteristic value for the fit of the components can be determined based on the geometric data defining the gaps. This value can then be used as a success criterion for the precision of the manufacturing process and / or for the quality of the treatment. This allows conclusions to be drawn about the overall quality of the insertion, which could, for example, be reflected in a decreasing volume or wall thickness of the spacers required for compensation over time or with each trial.Alternatively or additionally, systematic errors caused individually by the practitioner, such as a pre-drilling that is always slightly too deep or the like, can also be identified and used as a basis for compensation.

[0033] If, for example, the practitioner notices that all their implants are consistently inserted at least 1.0 mm too high or too low, this can be determined by a computer and taken into account when designing future surgical guides. Similarly, if the axial angle is always buccally inclined or always tilted in the same direction, the practitioner can consider this in future insertions and thus increase their precision. The same applies, of course, to all other spatial directions where a pattern is recognized by the software (preferably a computer).

[0034] Possible parameters to be considered in such an evaluation could include, but are not limited to:

[0035] 1. Wall thickness of the intermediate body, especially in the area of ​​space laterally surrounding the connecting element

[0036] 2. Volume or weight of the intermediate body (primarily an indicator of height accuracy)

[0037] 3. Wall thickness uniformity or tolerance

[0038] 4. Centricity of the abutment's male matrix in the recess of the prosthetic body

[0039] Advantageously, for a number of treatments, the characteristic parameters for the fit of the components are stored together with reference data characteristic of the respective treatment in a database. This allows for an evaluation of the stored data at a later time, for example, linked to pattern recognition or analysis, in order to identify aspects or factors that contribute to treatments considered particularly successful, as well as those considered unsuccessful or substandard. As a result, a recommendation for action can be generated for the user based on a number of the stored characteristic parameters for fit, in a manner considered to be independently inventive. This allows, among other things, the provision of personalized or individualized correction data, which leads to correction suggestions for the respective practitioner.

[0040] In a treatment system appropriately equipped for this purpose, user-specific parameters of the above-mentioned type can be stored in an independently inventive manner, so that individualized recommendations for action, in the form of individualized training or instruction, can be provided.

[0041] Alternatively or additionally, according to a further aspect of the invention, this stored data and characteristic values ​​can be used to determine and calculate possible improvements and adjustments to the template used for navigation, i.e., to modify the template's manufacturing process. The embodiments described above are particularly suitable for cases where the intermediate body is also intended as a temporary measure. In an advantageous embodiment, the intermediate piece thus produced can subsequently be removed and replaced with a final version made of a particularly durable material (e.g., ceramic, titanium, or the like).According to an aspect considered to be independently inventive, the geometric data acquired during the aforementioned fabrication of the intermediate body and stored in the database can be reused for the fabrication of the final intermediate body, since, by design, they comprise the geometric data actually required for the restoration. According to another aspect of the invention, the acquired intraoral data are therefore appropriately stored in the database, specifically with a suitable identifier and linked to it in a way that allows for the precise assignment to the respective patient and / or other treatment-relevant information, even at a later time, possibly years later.

[0042] The advantages achieved with the invention lie particularly in the fact that, by capturing intraoral data after implant insertion, the positioning and alignment intermediate body, which ensures precise alignment, can be manufactured with exceptional accuracy and precision, but especially quickly and flexibly, particularly when using a prefabricated prosthetic body. This enables high-quality provisional restoration of the patient on the day of implant insertion in a particularly cost-effective manner. A further advantage of the method is that, after fabrication of the intermediate body, it can be bonded extraorally to the crown or bridge and the connecting element to the implant, for example, an abutment, and does not require precise positioning within the patient's mouth during intraoral bonding.

Claims

Claims 1. A method for providing a connection between a number of at least two inserted dental implants and a prosthetic body, which is provided for each dental implant with a recess assigned to it and suitable for receiving a connecting element of the respective dental implant, wherein, after the insertion of the dental implants into the patient's jawbone, the intraoral data characteristic of the patient's oral situation, including the inserted dental implants, are recorded, wherein, based on this intraoral data, the geometric data defining the space formed by the connecting element and the assigned recess when the prosthetic body is correctly placed are determined for the connecting element of the respective dental implant, and an intermediate body filling the space is manufactured based on this data.

2. Method according to claim 1, wherein an abutment associated with the respective dental implant is used as the connecting element of the respective dental implant.

3. Method according to claim 1 or 2, wherein the recesses associated with the dental implants each have different geometries.

4. Method according to any one of claims 1 to 3, wherein the intermediate body or each intermediate body is manufactured using a 3D printing process.

5. Method according to claim 4, wherein the respective intermediate body is printed directly onto the connecting element of the respective dental implant.

6. Method according to any one of claims 1 to 5, wherein the geometry data defining the spaces are stored in a database.

7. Method according to one of claims 1 to 6, wherein a characteristic value for the fit of the components is determined on the basis of the geometry data defining the gaps.

8. Method according to claim 7, wherein, for a plurality of treatments, the characteristic values ​​for the fit of the components are stored together with reference data characteristic for the respective treatment in a database.

9. Method according to claim 8, wherein a recommendation for action for the user is determined on the basis of a plurality of the stored characteristic values ​​for the accuracy of fit.