PASSIVE FIT OF IMPLANT BRIDGES AND IMPLANT BARS BY MEANS OF A CAD/CAM TOOL FOR THE MODEL-FREE CREATION OF IMPLANT-SUPPORTED RESTORATIONS

Abstract

The invention relates to a specimen part (1) for creating a stress-free fit, a so-called passive fit, of implant-supported and/or abutment-supported bridges (2) and bars (3) by means of a CAD/CAM tool for the creation of restorations (5), and to a method for creating a restoration from a digital model (15) of a patient's jaw provided with at least two implants and/or abutments, wherein the model (15) is determined by means of an intraoral scan (14). In order to improve the precision of restorations and to shorten the production process, provision is made that the specimen part (1) per implant (4) and/or abutment has a scannable structure (6), preferably at a defined distance (7) and angle (8) to the implant (4) and/or abutment. In the method according to the invention, a specimen part (1) is produced from the model (15) by means of CAD/CAM, the specimen part (1) is checked in terms of its dimensional match to at least two implants (4) and/or abutments and if necessary is corrected, the specimen part (1) is scanned, and a digital model (15) of the optionally altered specimen part (1) is generated, which model is used to generate a restoration (16) manufactured by CAD/CAM.

Claims

1. A specimen part for creating a stress-free fit of implant-supported and/or abutment-supported bridges and bars by means of a CAD/CAM tool for the creation of restorations, the specimen part comprises a scannable structure at a defined distance and angle to at least one implant and/or abutment wherein the specimen part is joined to a separating point.

2. The specimen part according to claim 1, wherein the scannable structure is a conical prism.

3. The specimen part according to claim 1, wherein a second scannable structure is provided on a bar located between two implants and/or abutments.

4. The specimen part according to claim 1, wherein the specimen is produced from a plastic.

5. The specimen part according to claim 1, further comprising a screw channel for each implant.

6. A method for creating a restoration from a digital model of a patient's jaw provided with at least two implants and/or abutments, wherein the model is determined by means of an intraorally-created scan, comprising the steps of: creating a specimen part from the model by means of CAD/CAM; checking the specimen part for dimensional stability with respect to at least two implants and/or abutments and, if necessary, correct the specimen part by a separation the specimen part the at least two implants and/or abutments and rejoining to form a corrected specimen part; scanning the corrected specimen part; and generating a corrected digital model of the corrected specimen part, wherein the digital model or corrected digital model is used to produce a restoration manufactured by means of CAD/CAM.

7. The method according to claim 6, wherein the specimen part is provided with screw channels for each implant.

8. The method according to claim 7, wherein a suitable, scannable basic shape connected to the specimen part is provided at a predetermined distance and angle to each implant and/or abutment.

9. The method according to claim 7, wherein the specimen part is provided with at least one scannable two- or three-dimensional structure.

10. The method according to claim 6, wherein the intraoral scan is created using scan bodies that have a known shape and known dimensions, and are connected to the implants and/or abutments.

11. The method according to claim 6, wherein the corrected scanning step of the corrected specimen part takes place extra-orally.

12. The method according to claim 6, further comprising the step of entering a piece of information regarding the position of a separating point into the digital model of the specimen part or the corrected specimen part.

13. The method according to claim 6, further comprising the step of creating the restoration is created at least partially by means of stereolithographic methods.

14. The specimen part according to claim 1, wherein the stress-free fit is a passive fit.

15. The specimen part according to claim 1, wherein the specimen part is joined to a separating point by cementing.

16. The specimen part according to claim 2, wherein the scannable structure is a tetrahedron prism.

17. The specimen part according to claim 3, wherein the second scannable structure is a two-dimensional milled structure.

18. The specimen part according to claim 4, wherein the plastic is PMMA.

19. The method according to claim 6, wherein the separation takes place between the at least two implants and/or abutments in order to adapt the specimen part, which separation is connected by subsequent stress-free joiningpreferably, by casting or cementing.

20. The method according to claim 19, wherein the stress-free joining is by casting or cementing.

21. The method according to claim 9, wherein the at least one scannable two- or three-dimensional structure is located on a bar or bridge between two implants and/or abutments.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The method according to the invention and the apparatus according to the invention are explained using the drawings. Shown are:

[0047] FIG. 1 the work flow according to the invention in the creation of the restoration,

[0048] FIG. 2 a top view of a specimen part according to the invention, and

[0049] FIG. 3 a top view of a corrected specimen part.

EXEMPLARY EMBODIMENTS OF THE INVENTION

[0050] In FIG. 1, the large vertical blocks are assigned to the individual actors, i.e., the dentist, dental technician, and remote production, in the creation of a restoration. The blocks within the large blocks represent actions of the respective actor, wherein the sequence of the actions is indicated by connecting arrows.

[0051] The left block 19 thus contains the actions of the dentist, the central block 20 those of the dental technician, and the right block 21 the actions of a remote production site.

[0052] In the left block 19, the dentist thus initially creates an intraoral scan 22 of the jaw arches of a patient, from which scan a digital model of the jaw arches 23 is calculated by a program in known fashion. Subsequently, the dentist decides in accordance with the branching 24, whether he will follow the left stem of the branching and generates a CAD model 25 of the specimen part in a program-supported manner and produce it himself. Otherwise, he sends the data set of the digital model of the jaw arches to the dental technician acting in accordance with block 20 for the CAD/CAM-supported creation of the specimen part 25.

[0053] In both cases of the branching 24, the manufactured specimen part arrives at block 19 again, for try-on 26 in the patient's mouth. During the try-on, any mechanical stresses are removed by separating and rejoining, and the separating point is marked 27 in the digital model by means of a so-called slicing tool, so that the separating point in the model can be taken into consideration in the correction calculation.

[0054] In FIG. 1, the possibly corrected specimen part then returns at block 20 to the dental technician, who scans 28 the corrected specimen part. Alternatively, this scanning process can naturally also be performed with appropriate equipment by the dentist. The result of this scan and of the marked reference positions is then used as the basis for a re-calculation of one or more digital models, such as of the specimen part and/or of the jaw arch, from which a digital model of the restoration is then generated, after a computer-aided matching with the digital design templates, which digital model is finally the basis for the production 29 of the restoration.

[0055] After the CAD/CAM-supported creation of the specimen part, branching off from block 25, the data set of the first digital model of the jaw arches can already be handed over to block 21the remote productionso asoptionally, in parallelto order and have produced 30 a stereolithographically-created model with laboratory analogs, which model is then aesthetically veneered by the dental technician in block 31.

[0056] The restoration finished in this way is sent to the dentist for insertion 32.

[0057] As can be seen easily, this work flow advantageously dispenses with the creation of the customary master model. With appropriate equipment, all actions can also be performed at the dentist's practice.

[0058] FIG. 2 and FIG. 3 respectively show a top view of the same specimen part 1 according to the invention for testing a jaw arch with a total of four implants 4, which are located below the screw channels 5 during the try-on in the jaw arch. The specimen part 1 is screwed to the implants by means of the screw channels 5. Between the four screw channels 5 are located three bars 3, which can be separated at separating points 13 between the screw holes 5 into individual segments 10, as shown in FIG. 3. Naturally, a specimen part can also consist of only one bar, which connects two implants. Such a simpler specimen part is used for the creation of an implant bridge (FIG. 3). The basic work flow, however, remains the same as for the production of a larger restoration.

[0059] Instead of implants, teeth can also be used for anchoring the restoration, which teeth are often ground, in order to then be used as abutments or posts for the mounting of the restoration.

[0060] Finally, implants and abutment teeth can also be used in combination for anchoring.

[0061] Serving as reference points for the scanning and measuring of the specimen part by the software used are basic shapes 6, which are advantageously shaped as tetrahedrons, so that they can be easily detected. The tip 33 of the basic shape can be precisely marked in the enlarged image of the scan, since its distance 7 and angle 8 as reference values to the implants 4 and/or the screw channels result in a precise pattern that is included in the digital model of the specimen part 1. The change in the position of these scan bodies 17 after separating and rejoining of a bar can be used as a correction vector in the calculation of a corrected digital model of the specimen part.

[0062] In addition, a linear milled structure 12 aids as second structure 11, which can be easily used by the software using suitable pattern recognition for the more precise location-dependent correction calculation after the position change, in order to additionally increase the precision.

[0063] FIG. 3 indicates a situation in which the specimen part 1 fits on the three left implants, but can only be mounted on the right implant with force. The bar 3 is therefore separated at the separating point 13, and rejoined by cementing after mounting of the right segment 10 on the implant. The digital model of the jaw arch and/or of the specimen part is corrected based upon the correction data determined from a scan, and used as the basis for the construction and production of the restoration.

[0064] The specimen part according to the invention and the method according to the invention can, particularly advantageously, be used commercially in the precise and rapid production of aesthetic restorations of teeth.

REFERENCE SYMBOLS

[0065] 1 Specimen part [0066] 2 Implant bridges [0067] 3 Bridge bars [0068] 4 Implant [0069] 5 Screw channel [0070] 6 Basic shape [0071] 7 Distance [0072] 8 Angle [0073] 9 Tetrahedron [0074] 10 Segment [0075] 11 Second structure [0076] 12 Milled structure [0077] 13 Separating point [0078] 14 Intraoral scan [0079] 15 Model of the jaw arch? [0080] 16 Restoration [0081] 17 Scan bodies [0082] 18 Scanning [0083] 19 Left block [0084] 20 Central block [0085] 21 Right block [0086] 22 Creation of an intraoral scan [0087] 23 Creation of a digital jaw arch model [0088] 24 Branching [0089] 25 CAD/CAM-supported production of the specimen part [0090] 26 Try-on of the specimen part [0091] 27 Correction of the specimen part and marking of the separating point [0092] 28 Scanning and creation of the digital model of the corrected specimen part [0093] 29 CAD and production of the restoration [0094] 30 Ordering and manufacturing of an SLA model with laboratory analogs [0095] 31 Aesthetic veneering of the restoration [0096] 32 Insertion of the restoration [0097] 33 Tip