Method For Specifying A Material Color Of A Dental Restoration

Abstract

The invention relates to a computer program for specifying a material color of a dental restoration for which the desired tooth color is entered as a target tooth color (56) by the user, said target tooth color being the tooth color of a neighboring tooth, wherein upon specification of the material color of the dental restoration starting from the target tooth color (56) the material color of the dental restoration material is changed based on parameters such as the color of a stump and/or an abutment, the layer thickness of the dental restoration, the type of the dental restoration as well as the processing technique, wherein the specification of the material color of the dental restoration is controlled by the computer program, and wherein, once a parameter is selected, the next parameter is offered automatically, wherein the selection is limited based on parameters which are dependent on one another, such as the layer thickness, the restoration type, that is to say the indication, and the material.

Claims

1. A computer-implemented method for specifying a material color of a dental restoration comprising a desired tooth color is entered as a target tooth color by a user, said target tooth color being the tooth color of a neighboring tooth, said target tooth color specified as the material color of the dental restoration, upon specification of the material color of the dental restoration starting from the target tooth color the material color of the dental restoration is changed based on one or more parameters selected, wherein the specification of the material color of the dental restoration is controlled by the computer-implemented method, and wherein, once one of the one or more parameters is selected, a next parameter is offered automatically, wherein the selection is limited based on parameters which are dependent on one another.

2. The computer-implemented method as claimed in claim 19, wherein the material color of the dental restoration is changed with respect to the target tooth color depending on the layer thickness of the dental restoration, wherein a darker material color is specified for a brighter target tooth color (56) and a brighter stump and a larger layer thickness, and wherein a brighter material color is specified for of a darker target tooth color (56) and a brighter stump and a larger layer thickness.

3. The computer-implemented method as claimed in claim 1, wherein output of a material color is blocked or a solution is unsuitable without an opaquer for a darker stump and a brighter target tooth color (56) starting from a predefined difference in brightness.

4. The computer-implemented method as claimed in claim 1, wherein a change in material color is performed depending on the translucency of the dental restoration.

5. The computer-implemented method as claimed in claim 1, wherein the dental restoration is monolithic and consists of one material or one material class and comprises a material color which is the same in itself.

6. The computer-implemented method as claimed claim 1, wherein the dental restoration is monolithic and built up in several layers of same or different translucency, and wherein a vestibular or occlusal layer is more translucent or brighter than an oral or gingival layer.

7. The computer-implemented method as claimed in claim 19, wherein brightness of the material color of the dental restoration is increased when the stump color or the abutment color is below a predefined brightness threshold.

8. The computer-implemented method as claimed in claim 1, wherein the specification of the material color of the dental restoration is carried out based on the one or more parameters comprising the target tooth color, stump color and layer thickness of the dental restoration and optionally based on additional further parameters comprising a type of restoration, a processing technique and type of luting material.

9. The computer-implemented method as claimed in claim 8, wherein based on at least one of the one or more parameters, a material color is offered for selection, automatically in an app of a smartphone or in a CAD/CAM software.

10. The computer-implemented method program as claimed in claim 9, wherein the selection is limited based on parameters already specified, which parameters comprise the layer thickness, the indication and the material.

11. The computer-implemented method as claimed in claim 1, wherein a brighter material color is specified for a darker target tooth color and a dark stump color.

12. The computer-implemented method as claimed in claim 19, wherein the layer thickness relates to a thinner central position on a vestibular side of crowns, veneers and copings, and to a thinnest occlusal position for inlays and onlays.

13. The computer-implemented method as claimed in claim 19, wherein the method offers layer thicknesses larger than or equal to 1.0 mm for crowns, inlays and onlays as an indication, layer thicknesses starting from 0.3 mm for veneers and copings, and wherein maximum layer thickness is less than 2.0 mm or 1.5 mm.

14. The computer-implemented method as claimed in claim 1, wherein the tooth color is selected based on four or five parameters which are present in a tree structure such that upon selection of one of the parameters only matching ranges of other parameters are offered, and wherein the four or five parameters comprise tooth color, indication, stump color, layer thickness, and material of the dental restoration to be used.

15. The computer-implemented method as claimed in claim 1, wherein impossible combinations of parameters are blocked by the method or displayed as not realizable and/or wherein based on the layer thickness the tooth color group (A, B, C, D) is adapted if necessary to optimize the visual impression of the material color to be produced.

16. The computer-implemented method as claimed in claim 9, wherein in a result region of the app of a smartphone or the CAD/CAM software, both the target tooth color (56) and the recommended material color is displayed and wherein in the result region the indication is displayed in a graphically approximated manner.

17. The computer-implemented method as claimed in claim 1, wherein on a result screen a further alternative color is displayed and also shown in color in addition to an optimum and recommended material color of the dental restoration part.

18. The computer-implemented method as claimed in claim 1, wherein on a result screen a free selection of the material color is offered, via which the user may display different material colors for visual comparison with the target tooth color.

19. The computer-implemented method as claimed in claim 1, wherein the one or more parameters comprises a color of a stump and/or an abutment, a layer thickness of the dental restoration, a type or indication of the dental restoration, a material and a processing technique.

20. The computer-implemented method program as claimed in claim 11, wherein the brighter material color specified has a tinge of red, the darker target tooth color is C4, and the dark stump color is ND8.

Description

[0061] Further advantages, details and features may be taken from the following description of several exemplary embodiments in conjunction with the drawings, in which:

[0062] FIG. 1 shows a selection diagram within a computer program of an inventive method in one embodiment;

[0063] FIG. 2 shows a selection view for a target tooth color in the embodiment according to FIG. 1;

[0064] FIG. 3 shows a view according to FIG. 2, however illustrating other target tooth colors;

[0065] FIG. 4 shows a view according to FIG. 2, wherein, however, a tooth color has already been selected and the indication is due for selection;

[0066] FIG. 5 shows a view according to the FIGS. 2 to 4, wherein both the tooth color and the indication have been selected and the stump color is due for selection;

[0067] FIG. 6 shows a view according to the FIGS. 2 to 5, wherein tooth color, indication and stump color have been selected and the layer thickness is due for selection;

[0068] FIG. 7 shows a view according to the FIGS. 2 to 6, wherein tooth color, indication, stump color and layer thickness have been selected and the material is due for selection;

[0069] FIG. 8 shows an illustration of a result field, wherein there is no suitable selection according to the illustration such that no result is obtained;

[0070] FIG. 9 shows an illustration of the result field according to FIG. 8, wherein a result is shown;

[0071] FIG. 10 shows an illustration of an information field with regard to FIG. 9 which reflects the parameters of the result;

[0072] FIG. 11 shows an illustration of a selection screen according to the FIGS. 2 to 7 wherein the layer thickness is due for selection and no further selection has been made up to now;

[0073] FIG. 12 shows an illustration according to FIG. 11 wherein the stump color is due for selection and no further selection has been made up to now; and

[0074] FIG. 13 shows an illustration according to the FIGS. 11 and 12 wherein the stump color ND3 has been selected and the tooth color is now due for selection.

[0075] A possible process diagram of the program for providing the inventive method is illustrated in FIG. 1. The program part illustrated herein relates to the selection of the parameters, of the following parameters in the exemplary case: target tooth color, indication or type of dental restoration, stump color, thickness of the restoration layer and the material used.

[0076] When the parameter field of tooth color is selected, it is possible to select from numerous possible target tooth colors, They comprise the tooth colors BL1 to BL4, A1 to A4, B1 to B4, Cl to C4 and D1 to D4, that is to say 20 tooth colors altogether which are grouped in correspondence with the letters in a way known per se. One corresponding selection field each is available for selecting the tooth color which reflects the respective tooth color for the tooth shape.

[0077] The user, that is to say e.g. the dentist, determines the tooth color of the neighboring tooth or the neighboring teeth either based on a tooth key or a mini color key according to EP 2 255 749 B1.

[0078] Alternatively, when the inventive method is realized by means of a tablet or a smartphone, the respective tooth color field displayed may also be held next to the tooth without further ado to allow for visual assessment.

[0079] In case of smartphones or tablets, the fields in question may be selected via touchscreen in a way known per se, wherein it is to be understood that instead control via a mouse is also possible, especially with regard to the realization as a separate or integrated program on a computer which is also intended for the CAD design. It is also possible to enter the tooth colors via a keyboard or any other suitable input device.

[0080] Automatic offering is an essential element of the inventive method. Thus, when a parameter such as the tooth color has been selected, the possible selection jumps directly further to the next parameter and offers the then still available parameters thereat. Any excluded possible selections are displayed e.g. in a grayed out fashion, or it is made clear in another fashion that they are not available for selection.

[0081] The empirical determination performed in advance of the color and translucency effect of different combinations of the parameters which were incorporated into the programing of the computer program allows for exclusion of certain combinations of parameters by the inventive computer program. This is described in more detail below.

[0082] However, in correspondence with the counter arrow 10 according to FIG. 1 it is also possible to select a changed tooth color again directly after selection of the tooth color. For this purpose, the user shortly taps the parameter field tooth color again. The parameter field selected in this way which allows for selection of the possible selections is marked active by a suitable mark.

[0083] If no new correction is required, the user is automatically led to the next field. In the exemplary embodiment illustrated, this is the indication wherein the possible selections veneer, inlay, onlay, crown and coping are available. Basically, these possible selections apply to all tooth colors such that no limitations or else correspondingly grayed-out fields are provided in this respect. Needless to say, in addition to the already mentioned possible selections further indications such as bridges, abutments, occlusal veneers (table tops) and the like and also corresponding materials (e.g. titanium for abutments) are also possible by a corresponding extension of the programing.

[0084] Here, too, there is the possibility of performing correction, corresponding to the counter arrow 12. Then again, the user may return to the tooth color again and thus follow the counter arrows 12 and then 10.

[0085] When no corrections are desired, the next possible parameter selection appears automatically, which is the stump color in the present case. Now it is possible to select between the bright stump color ND1 and the dark stump color ND9 but also to select the intermediate stump colors ND2 to ND8.

[0086] Then again, here too, the same correction possibility is available analogously by following the execution path according to counter arrow 14.

[0087] The next possible selection applies to the layer thickness of the dental restoration. Here, substantial limitations are already provided as soon as the indication has been selected. Thus, veneers may be specified with a thickness of between 0.3 mm and 1.5 mm, that is to say with all 12 possible selections. But inlays or onlays may only be provided with a minimum depth of 1.0 mm such that in this case only the 6 possible selections from 1.0 mm to 1.5 mm are illustrated as active. As a result, layer thicknesses of less than 1.0 mm are automatically illustrated as excluded by the computer programthey are displayed in a grayed-out fashion and are not available anymore for selection as a possible parameter.

[0088] The selection crown also offers the possibility of selecting a layer thickness of between 1.0 mm and 1.5 mm, but not less. In case of the indication selection coping the selection of 0.3 mm is blocked while the remaining possible selections are available.

[0089] Now, when the user changes his/her mind with regard to the displayed selection as it were and selects e.g. another tooth color and follows the counter arrows 16, 14, 12 and 10 in this respect, the selections made up to nowprovided that they are adequateremain unchanged, and only the appropriate possible selections are offered now.

[0090] However, this means that when e.g. the value of 0.3 is set for the layer thickness and then the user returns to the indication up to the counter arrow 12, only veneer remains for selection as only the indication veneer is available for the layer thickness of 0.3. In this respect, here, too, the selection is automatically limited to the combinations realizable in the production of the dental restoration by the computer program based on the combination of the parameters already entered.

[0091] If no correction is made it is possible to select the material wherein the materials CAD, Press and ZirCAD are available in the exemplary embodiment illustrated. As has already been mentioned further above, further materials such as titanium (for abutments) may be added when the programming of the computer program is extended.

[0092] It is to be understood that any other materials may also be offered in this respect, such as also explicitly composite, lithium disilicate or the like.

[0093] Now, here, it is also possible to change the selection made up to now corresponding to the counter arrow 18.

[0094] When all the selections have been made, which is shown by corresponding marks of the parameter fields, the display of the result is inventively activated instead of selection fields. Here, generate result may e.g. be displayed, and a result screen is now displayed upon this selection. The result screen shows both the selected tooth color in the shape of a tooth and the material color, and additionally the material color name such as HT BL1 or the like. HT indicates a material of high transparency.

[0095] The suggested material color is made up of the stump color, the transparent cement and the restoration color wherein the layer thickness of the restoration in correspondence with the indication is also taken into account by the computer program. The total color of the dental restoration is then illustrated like it would be represented in the mouth of the patient.

[0096] In addition to this, the dental restoration material to be produced is also illustrated symbolically with the determined material color corresponding to the indication.

[0097] It is to be understood that in addition to a graphic output on a result screen a voice output may also be performed for instance.

[0098] In an advantageous configuration it is provided that a preferred material color, i.e. the primary material color, and additionally a secondary material color is displayed, and in a further advantageous configuration also free possible selection additionally.

[0099] Then, the user has the opportunity of illustrating the different results next to one another and of optimizing them visually or else by comparison with the target tooth color.

[0100] In a further advantageous configuration it is also possible either to make a correction based on the determined result, to illustrate the underlying parameters, to print the result or to send it.

[0101] A selection screen 19 is illustrated in FIG. 2. Parameter fields 20, 22, 24, 26 and 28 which are labeled tooth color, indication, stump color, layer thickness and material are in the upper region of the selection screen. The parameter field which is active respectively, the parameter field 20 in the present state, is marked or has a dark background.

[0102] Selection fields 30 to 40 are in the bottom region of the selection screen 19. The visible selection fields are labeled as follows: [0103] Selection field 30-BL1 [0104] Selection field 32-BL2 [0105] Selection field 34-BL3 [0106] Selection field 36-BL4 [0107] Selection field 38-A1

[0108] Next to them, a selection field 40 is partly visible which would correspond to the selection field A2. By a corresponding swiping finger gesture, any desired section of 5 or 6 tooth colors from the visible field string or strip of the possible 19 target tooth colors may be displayed, the tooth colors C3, C4, D2, D3 and D4 according to FIG. 3.

[0109] By tapping one of the selection fields, the respective selection field is selected, and without further measures a change of screen is immediately performed to the selection screen 42 according to FIG. 4. The parameter field 20 with the selected tooth color BL1 continues to be marked dark, and at the same time the parameter field 22 is marked while the selection fields 24 to 28 are unmarked.

[0110] Accordingly, the selection fields 30 to 38 show the different indications or restoration types, namely the selection field 30 a veneer, the selection field 32 an inlay, the selection field 34 an onlay, the selection field 36 a crown and the selection field 38 a coping. By tapping the desired selection field, the selection is triggered and the selection screen 44 according to FIG. 5 appears. The parameter field 24 stump color is active and five stump colors are displayed in the region of the selection fields 30 to 38, ND1 to ND5 in the illustrated exemplary embodiment, wherein it is also possible to arrive at another selection up to ND9 by scrolling.

[0111] By selection of the stump, the screen changes again to FIG. 6 with the selection screen 46 for selecting the layer thickness in the parameter field 26. In this way, the layer thicknesses possible in correspondence with the indication are shown as active and may be selected, wherein impossible layer thicknesses are shown as not active and thus grayed out. Thus, the not possible and in this respect not active layer thicknesses may not be selected by the user at all, they are automatically blocked by the computer program. Thus, maloperation by the user is excluded.

[0112] In accordance with the selection screen 48 in FIG. 7, the material to be used is still to be specified with the parameter field 28, wherein CAD, Press and ZirCAD are possible.

[0113] Once the respective selection is made, a not illustrated intermediate screen appears which offers the possibility of generating the result, wherein, however, a correction of the selection is additionally possible in accordance with the counter arrows in FIG. 1.

[0114] Once generate result is tapped, the result screen according to FIG. 8 appears. The following combination was selected in the exemplary embodiment illustrated: Tooth color BL1, veneer, ND3 as stump color and 1.2 as layer thickness and Press as material.

[0115] Although the stump color ND3 is not particularly dark, it may not be combined with BL1 such that the result would be satisfactory. Thus, in accordance with FIG. 8, no result is displayed in the primary result field 52 and in the secondary result field 54. By contrast, the target tooth color 56 is illustrated both as a letter/number combination and as a correspondingly shaped and shaded tooth in the left region. Via the add field 58 a further selection may be made if necessary.

[0116] The missing suggestions in the result fields make clear to the user in a program-controlled way that the combination of the parameters selected in advance would not lead to the desired result and thus a correction to at least one of the input parameters is necessary.

[0117] An alternative result screen 50 is illustrated in FIG. 9. Here, instead of the tooth color BL1 the tooth color A4 was selected. Here, it is possible to prepare a useful restoration in an aesthetically particularly satisfactory manner. LT A3.5 is suggested as a material tooth color in the primary result field 52. In the secondary result field 54 HT A3.5 is suggested. A result image is illustrated in a region 60 which is to illustrate a veneer with the determined primary result field tooth color.

[0118] By tapping an information icon 62 the underlying parameters may additionally be displayed again according to FIG. 10, that is to say A4, veneer, ND3, 1.2 and Press. Here, the configuration may be edited again via a field 64 if necessary.

[0119] By way of example, it is referred to the following results of the following compilations of parameters.

TABLE-US-00001 target tooth stump layer material color indication color thickness material color A3 inlay ND4 0.3 CAD not possible A3 inlay ND4 0.6 CAD not possible A3 inlay ND4 1.0 CAD HT BL2 A3 inlay ND4 1.2 CAD HT BL4 A3 inlay ND4 1.5 CAD HT BL4 A3 veneer ND4 0.3 CAD not possible A3 veneer ND4 0.6 CAD not possible A3 veneer ND4 0.9 CAD MT BL2 A3 veneer ND4 1.2 CAD MT BL2 A3 veneer ND4 1.5 CAD MT A1

[0120] As is apparent, the inventive method leads to darker material colors in case of larger layer thicknesses in case of inlays provided primarily occlusally as well as in case of vestibularly visible crowns as the stump may be covered better due to the larger layer thickness and thus has less influence on the total color effect.

[0121] Additionally, the free selection field 66 according to FIGS. 8 and 9 may display and graphically illustrate any selection from the range of available material tooth colors.

[0122] According to FIG. 11, an alternative selection screen 46 is illustrated. Here, the parameter fields 20 to 26 are not marked and accordingly not dark. By contrast, the parameter field 26 for the layer thickness is active and dark and in the region of the selection fields 30 to 38 possible layer thicknesses are illustrated for selection accordingly. A corresponding state is created when the layer thickness according to the parameter field 26 is tapped first instead of the tooth color. In this state, the tooth color has not been selected yet, but after tapping a certain layer thickness via the fields 30 to 38 possible selection may be made corresponding to the selection screen 19, wherein the layer thickness according to the parameter field 26 remains selected as a matter of fact.

[0123] This is illustrated analogously in the same manner in FIG. 12 for the stump color 44 according to the selection screen 44 thereat. Here, too, none of the other parameters is specified in advance, and it is possible to select the stump color initially.

[0124] When this is done, the modified selection screen 19 appears according to FIG. 13 in which the tooth color according to the parameter field 20 is marked as active and the tooth color is selectable via the selection fields 30 to 38 accordingly.