Method for defining different layer elements of an artificial tooth element - Patents.com

Abstract

The present invention relates to a method for defining different layer elements of an artificial tooth element, the method comprising the steps of: defining an interface between an inner core element (38) and an outer layer element (50) at least partially surrounding the inner core element (38); selecting an additional layer element (60, 62, 64, 66) from a provided selection list including a plurality of additional layer elements; and automatically positioning at least one selected additional layer element (60, 62, 64, 66) in a spatially defined relationship relative to the core element (38) and / or the outer layer element (50).

Description

[Technical Field]

[0001] The present invention relates to a method for defining different layer elements of an artificial tooth element. [Background technology]

[0002] When manufacturing artificial tooth elements, it is an essential aim that the artificial tooth elements resemble as closely as possible in appearance to the patient's natural teeth. In natural teeth, the dentin is surrounded by enamel in the visible area. It is particularly difficult to imitate the appearance of old teeth, since old teeth often exhibit additive effects.

[0003] To produce tooth elements that can be complete artificial teeth or crowns, it is known to produce tooth elements from at least two different materials and reproduce the interface between dentin and enamel. For this purpose, German Patent Application Publication No. 102010002484 discloses using an X-ray method to determine the interface between dentin and enamel of a natural patient's tooth, followed by producing tooth elements in which the inner material mimicking the dentin has the same geometric shape as the patient's natural dentin, and in particular, forming an enamel-replacing material with a layer thickness corresponding to that of natural enamel. Since the enamel-replacing material in the artificial tooth element does not have the same optical properties as the natural material, the optical appearance of the artificial tooth element produced in this way still differs from the optical appearance of the patient's other teeth. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] German Patent Application Publication No. 102010002484 Summary of the Invention

[0005] It is an object of the present invention to provide a method for defining the different layers of a prosthetic tooth element in order to provide a prosthetic tooth element whose optical properties correspond to or are as close as possible to the optical properties of the patient's natural teeth.

[0006] According to the invention, this object is achieved by a method as defined in claim 1.

[0007] According to the method of the present invention, an interface is first defined between an inner core element and at least one outer layer element at least partially surrounding the inner core element, where the inner core element corresponds to a portion of the tooth that includes dentin compared to a natural tooth, and the outer layer element corresponds to a portion of the tooth that includes, among other things, enamel compared to a natural tooth.

[0008] The interface can be defined by imaging the actual interface between the enamel and dentin of the natural tooth being replicated.

[0009] Preferably, at least one interface is defined inside the artificial tooth element, which does not necessarily correspond to a natural interface. The at least one interface represents the interface between at least two different materials from which the artificial tooth element is made. This interface does not correspond, or at least does not correspond completely, to the interface between the dentin and enamel of the patient's natural teeth, or is not defined taking into account the actual interface. By defining at least one other interface, i.e., an interface that is at least partially different from the natural interface, the optical properties of the materials used are adapted so that the optical appearance of the artificial tooth element thus produced is as close as possible to, and preferably essentially corresponds to, the optical appearance of natural teeth.

[0010] First, the three-dimensional outer contour of the tooth element can be determined. Here, the outer contour of the artificial tooth element corresponds to the outer contour of the natural tooth to be replaced. This can be done, for example, by selecting a suitable outer contour from a tooth library adapted to the individual anatomical structure so as to meet the functional and aesthetic requirements of the restoration to be manufactured. As an alternative to selecting a shape from a tooth library, for example in the case of a single tooth crown, it is also possible to mirror the contour of the opposing tooth. In particular, in a step performed prior to the method of the present invention, the three-dimensional outer contour of the tooth element can be determined, in particular detected. It is also possible to open a data set containing the three-dimensional outer contour of the tooth element.

[0011] Furthermore, to prepare the method of the invention, the three-dimensional outer contour of the tooth element can be aligned to a coordinate system. The coordinate system is preferably related to an anatomically defined direction designation, so that the coordinate system includes, in particular, the mesial, distal, apical and incisal / occlusal directions. Aligning the tooth element to a coordinate system has the advantage that, based on the three-dimensional outer contour of the tooth element, it is possible to define in a simple manner at least one boundary surface located on the inside of the tooth element.

[0012] A first boundary curve is defined on the tooth surface. The first boundary curve can be defined based on the tooth equator. The tooth equator is the maximum circumference of the tooth in the region of the crown. The first boundary curve can also be based on a curved preparation boundary, which is the boundary between the artificially prepared tooth element and the unprepared tooth surface. The first boundary curve can also be defined at least partially manually. Furthermore, it is possible to manually adjust an automatically defined curve, for example, based on the tooth equator and / or the preparation boundary. Preferably, the first boundary curve is defined between the tooth equator and the preparation boundary. Here, for example, the first boundary curve can be defined at a fixed distance to the tooth equator and / or the preparation boundary. In particular, the first boundary curve can have the same distance to the tooth equator and the preparation boundary, i.e., it can be precisely located between the tooth equator and the preparation boundary.

[0013] The incisal or occlusal tooth surface is determined with reference to the first boundary limit. According to the present invention, this tooth surface is displaced inwards. The displacement is in the direction of the surface normal, and in particular by different amounts. Thus, there are more or less surface areas of the tooth surface that are displayed inwards. These different displacement amounts are based on variable design parameters. At least one boundary surface is created by such displacement of the tooth surface.

[0014] The design parameters may vary, particularly for different teeth of a patient. Due to the translucency of the materials used for the artificial tooth elements, the optical appearance of the tooth stumps affects the appearance of the artificial tooth elements, so different design parameters may be necessary, for example, if restorations are performed on tooth stumps of different colors or if the restorations are designed with different thicknesses. The design parameters also depend, in particular, on the material used. For example, a minimum wall thickness of the material can be predefined. This is especially the case for inner, especially ivory-colored, materials, which primarily determine stability. Furthermore, the optical properties of polymer-based materials differ from those of pure ceramic materials.

[0015] In a preferred development of the method, the variable design parameter represents a maximum first displacement of the tooth flank and / or a first length for defining the transition surface.

[0016] Here, the first displacement is preferably selected for anterior and lateral teeth so that the displacement does not occur directly at the first boundary curve. Furthermore, for lateral teeth, no displacement occurs at the central crack. The amount of the first displacement preferably increases continuously from the first boundary curve toward the incisal or occlusal side in the direction normal to the surface until the amount of displacement reaches the maximum first displacement.

[0017] The transition surface may be defined, for example, by setting the design parameters of the first length. Preferably, the first length thus defines a transition region starting from the first boundary curve. The same is defined from 0 to the full first displacement. The transition region is provided to achieve a particularly smooth transition from the first boundary curve to the full first displacement. Defining such a transition surface allows for the reproduction of a natural tooth appearance, where the enamel thins further apically.

[0018] The transition surface may also be defined in such a way that a first boundary curve is projected a first length toward the incisal or occlusal edge, whereby a second boundary curve is defined by this projection, in which case the transition surface is defined between the first boundary curve and the second boundary curve. Therefore, the definition of at least one boundary surface inside the artificial tooth is at least defining a first boundary curve on the tooth surface; determining a tooth surface that is incisal / occlusal to the first boundary curve; - displacing the tooth surfaces inwards by different amounts in the direction of the surface normal to create said at least one boundary surface, in particular said first boundary surface; It is particularly preferred that the composition contains:

[0019] The variable design parameters preferably represent the maximum first displacement of the tooth surface and a first length for defining the transition surface, and during the first displacement, the displacement does not occur directly at the first boundary curves of the anterior and lateral teeth, and further at the central crack of the lateral teeth, but rather the amount of the first displacement in the direction normal to the surface increases continuously from the first boundary curve toward the incisal or occlusal side until the maximum first displacement is reached, and the first length is set as the design parameter.

[0020] Additionally, the first boundary curve may be projected a first length toward the incisal / occlusal side to define a second boundary curve, and a transition plane is defined between the first boundary curve and the second boundary curve.

[0021] According to the present invention, after defining the interface between the inner core element and at least one outer layer element at least partially surrounding the inner core element, at least one additional layer element is selected. According to the present invention, the additional layer element is selected from a provided selection list containing a plurality of additional layer elements. In particular, this may be a selection list or selection box displayed on a monitor, so that the dentist or dental technician can easily select individual or several additional layer elements included in the selection list, for example, by simply clicking or marking. Thus, the dentist or dental technician does not need to model or otherwise create the additional layer elements, but only needs to select them. According to the method of the present invention, the at least one selected additional layer element is automatically positioned in a spatially defined relationship with respect to the core element and / or the outer layer element. In some cases, the automatic positioning can be displayed directly on the monitor, so that the dentist or dental technician, by selecting one or more additional layer elements, already has a first impression of whether the optical appearance of the artificial tooth to be inserted is close to that of a natural tooth.

[0022] The automatic positioning of the at least one selected additional layer element is performed in a spatially defined relationship with respect to the core element and / or the outer layer element. Preferably, the automatic positioning is based on anatomical features and / or auxiliary lines or auxiliary points. The auxiliary lines and / or auxiliary points are preferably applied or defined based on anatomical features of the surface. In particular, the anatomical features and definition of the auxiliary lines and / or auxiliary points are different for each layer element. Preferably, this is done as described below for each layer element. Selection lists, in particular, It may include accentuation of incisal mamelons, and / or colored cervical areas, and / or translucent effects, and / or halo effects, and / or horizontal bands, and / or surface effects.

[0023] The additional layer elements "Translucent effect" and "Halo effect" are in particular subsets of the additional layer element "Incisal / occlusal optical effect".

[0024] To further improve the optical appearance of the additional tooth elements, it is preferably possible to select materials and / or colors for at least each additional layer element. The additional layer elements may also be made of different materials and have different colors or color gradients. If additional layer elements are provided in an additional tooth element not only once but several times, it is preferably possible to select different materials, colors, etc., so that the corresponding material and / or color selection can be performed separately for each additional layer element.

[0025] To select an "incisal node emphasis", it is preferably arranged on the core element in the region of the incisal node. At least one incisal node is preferably defined by a boundary surface. A plurality of additional layer elements can be formed in such a way that different additional layer elements "incisal node emphasis" are arranged on different incisal nodes. In particular, the additional layer element "incisal node emphasis" is preferably arranged at least partially on the outer layer element. In particular, to form the additional layer element "incisal node emphasis", the boundary surface is displaced at at least one incisal node. The displacement of the boundary surface occurs in particular in the incisal direction.

[0026] The additional layer element "Incisal Node Emphasis" is preferably placed at the incisal node defined by the boundary surface. In particular, the additional layer element "Incisal Node Emphasis" is set at the incisal node in a manner similar to a hood or hat.

[0027] In a preferred development of the method according to the invention, at least one control point of the incisal node is defined. Preferably, the control point is a vertex. The vertex defines the tip or the top of the incisal node. Preferably, the control point, in particular the vertex, is displaced in the incisal direction. The low points, i.e. the lowest points between adjacent incisal nodes, are preferably not displaced. Thus, the polygon defining the outer contour of the incisal node has maxima corresponding to the vertices of the incisal node and minima corresponding to the low points of the valleys between the incisal nodes. Thus, in a preferred embodiment, the maxima of the polygon are displaced in the incisal direction, and the minima are not displaced.

[0028] It is particularly preferred that the additional layer element "incisal node accentuation" is formed in the region between the boundary surfaces before and after the boundary surface displacement, which is preferably in the range of 0 to 1 mm, in particular in the range of 0 to 0.7 mm.

[0029] To define such a polygon, a third or further boundary curve can first be defined or created. This is done by projecting the first or second boundary curve a second length, with the provision of a second boundary curve being optional. In particular, the third or further boundary curve can be created by projecting the incisal or occlusal side of the first boundary curve, or by projecting the apical end of the second boundary curve. Alternatively, the third boundary curve can be created manually or independently of the first or second boundary curve, based on other features of the tooth element, such as the equator or preparation boundary.

[0030] Furthermore, preferably, a first surface contour is determined on the incisal or occlusal side. The first surface contour is defined by the highest curve on the first interface created by the first maximum displacement. The highest curve is determined automatically and can be manually corrected if necessary. Nodes are created or defined on the first surface contour. The nodes are then at least partially displaced in the apical or incisal / occlusal direction. The at least partially displaced nodes are interconnected to form the second surface contour. The second surface contour thus created defines a second maximum displacement of the tooth surface (or the first interface surface) in the region of the incisal or occlusal contour. Preferably, two different incisal node curves causing the second displacement are created according to the method steps described below. Here, the two different incisal node curves create two different geometric shapes. By "subtracting" the smaller geometric shape from the larger geometric shape, space is obtained for the placement of an additional layer element, "Incisal Node Enhancement."

[0031] In this preferred embodiment of the method according to the invention, the amount of second displacement decreases continuously towards the surface normal by a third length in the apical direction in the case of anterior and lateral teeth, until it reaches the third boundary curve or a length defined as maximum for that purpose. In lateral teeth, the amount of second displacement also decreases continuously towards the central fissure until it reaches the central fissure. Preferably, the amount of displacement in the immediate vicinity of the third boundary curve or in the immediate vicinity of the central fissure is "0". The central fissure may also be defined manually and / or manual correction of an automatically defined or predetermined central fissure may be performed.

[0032] Preferably, the maximum first displacement of the tooth flank is in the range of 0 mm to 4 mm.

[0033] Furthermore, the first length required to create the transition surface preferably has an extension of 0.1 mm to 10 mm.

[0034] In a preferred development of the invention, the boundary, i.e., the beginning and end of the automatically determined highest curve on the first and / or second incisal surface contour, is defined by an angle in the case of anterior teeth. The angle is the angle between the tangent to the incisal surface contour and the tooth axis, which angle is between 0° and 90°, preferably between 10° and 70°, particularly preferably between 40° and 50°. For teeth, the tooth axis is defined as the connecting line between the root tip and the center of the incisal surface or the chewing surface in single-rooted teeth, and between the root furcation and the center of the chewing surface in the case of multi-rooted teeth. In particular, it is also possible to manually define or adjust the boundary, i.e., the beginning and end, and the course of the incisal surface contour.

[0035] Preferably, the positions of the nodal points on the incisal contour of the anterior teeth are indicated or defined with respect to the entire length of the incisal contour, with at least five points being defined on the incisal contour, although it is preferred to define more points, in particular more than 10 points, and particularly preferably more than 20 points.

[0036] For lateral teeth, the location of the nodal points on the incisal / occlusal contour is preferably indicated for each cusp in terms of the length of the cusp ridges. In particular, the length of the cusp ridge between the mesial start of the cusp and the tip of the cusp, or between the tip of the cusp and the distal end of the cusp, is used. Furthermore, it is preferred that at least five points are defined per cusp over the entire length of the occlusal contour. More points, at least 10, and especially at least 20 points, are preferred.

[0037] The apical displacement of the nodal points on the incisal / occlusal contour is preferably in the range of -4.0 to +4.0 mm.

[0038] In addition to or instead of providing one or more additional layer elements "incisal node accentuation", an additional layer element "cervical coloring" can be selected. In order to match the optical appearance of the artificial tooth element to that of a natural tooth, it is often possible and necessary to match, and in particular darken, the tooth color, especially in the cervical region. Here, it is particularly preferred to use a material that is darker than the color of the dentin. In particular, this means coloring the tooth to a yellowish and / or brownish color.

[0039] If the additional layer element "colored neck" is selected, the material is at least partially colored in the area of ​​the outer layer element that is located apical to the boundary curve.

[0040] The material of the outer layer element can be colored to form the additional layer element "colored neck." Additionally or alternatively, an additional element of another material may be provided to design the additional layer element "colored neck." In this case, it is preferably disposed within the outer layer element. Since the outer layer element may not extend into the region below the neck, the outer layer element may not be provided in the region where the additional layer element "colored neck" is to be disposed. In this regard, the additional layer element "colored neck" may also be provided in whole or in part on the core element, which may form the outer layer of the artificial tooth element in the region of the neck.

[0041] The additional layer element "colored neck" is preferably limited by the outer contour of the outer layer element. In order to improve the optical appearance, it is also possible to arrange the additional layer element "colored neck" partially below the outer layer element, especially if the outer layer element extends completely under the tooth so that at least part of the neck is covered by the outer layer element.

[0042] Furthermore, it is possible to vary the layer thickness of the additional layer element "colored neck", in particular by designing a continuous color gradient, so that the layer thickness decreases in particular in the apical and / or incisal or occlusal direction.

[0043] In addition to or instead of the above-mentioned additional layer elements "incisal tubercle emphasis" and / or "colored neck", it is preferred to provide an additional layer element "incisal / occlusal optical effect". The additional layer element "incisal / occlusal optical effect" is in particular the additional layer element "translucent effect" or "halo effect".

[0044] The translucent or transparent effect often occurs in the incisal region of the crown or tooth. The additional layer element "translucent effect" is preferably arranged in the incisal region of the artificial tooth element within the outer layer element. Here, the additional layer element "translucent effect" is preferably limited by the outer contour of the outer layer element, in particular the additional layer element "translucent effect" is arranged at the outer edge of the artificial tooth, so that the additional layer element "translucent effect" forms the outer contour of the tooth.

[0045] For the definition of the additional layer element "semi-transparent effect", it is preferred to automatically position control points on the surface of the outer layer element, which are then displaced to the apex.

[0046] The additional layer element "Translucent effects" is preferably arranged as described for the additional layer element "Incisal nodule emphasis" in relation to the definition of the polygon, however in this case it is preferable to have a smaller outer contour.

[0047] The displacement is preferably along the normal to the surface of the outer layer element, and particularly preferably a displacement of 0 to 1 mm, in particular 0 to 0.5 mm.

[0048] Furthermore, an additional layer element "semi-transparent effect" is preferably formed in the region between the surfaces of the outer layer element before and after the displacement, where the outer contour of the additional layer element "semi-transparent effect" is particularly preferably limited by the original outer contour of the outer layer element.

[0049] A further optical effect is a halo effect. Therefore, the dentist or dental technician can select the additional layer element "halo effect" in addition to or instead of the above-mentioned additional layer elements. The halo effect is a slight brightening of the incisal edge of the artificial tooth element. This is usually not as noticeable as translucency. Preferably, the additional layer element "halo effect" is positioned, sized, etc. in the same way as the additional layer element "translucent effect". Preferably, the noticeableness of the additional layer element "halo effect" is less than that of the additional layer element "translucent effect".

[0050] A further additional or alternative additional layer element is the additional layer element "horizontal band".

[0051] Horizontal Band: For the automatic placement of the additional layer element "horizontal band", it is preferred that a horizontal line is first defined on the tooth element. With reference to the height of the tooth element, it is preferred to locate the horizontal line in an approximately central region of the tooth element. In particular, the horizontal line is defined relative to ±10% of the height of the tooth element. Starting from the horizontal line, the horizontal band extends over a predetermined width in both directions. The width is preferably in the range of 0.3 mm to 2 mm. In addition to this incisal / apical dimension, the horizontal band preferably has a depth of 0.2 mm to 1.5 mm. It is further preferred that the horizontal band is located between the core element and the outer layer element, and in particular extends into the core element and / or the outer layer element.

[0052] As with the other additional layer elements, the additional layer element "horizontal band" may have a choice of material, possibly several different materials, and coloring, which may again be a color gradient or different colors.

[0053] A further additional layer element is the additional layer element "surface effect". The additional layer element "surface effect" is arranged at the anterior interface (i.e., the surface between the core element and the outer layer element). The anterior region is the anterior visible part of the tooth when the tooth element is in place. The additional layer element "surface effect" is particularly related to the incisal edge. For the arrangement of the additional layer element "surface effect", in particular, a virtual grid can be arranged at the interface. The virtual grid has crossing points or intersections. By selecting the corresponding intersections, the area in which the additional layer element "surface effect" is arranged can be defined. The additional layer element "surface effect" preferably has a width of 1 to 8 mm, a height of preferably 1 to 10 mm, and a depth of preferably 0.1 to 1 mm. Furthermore, the additional layer element "surface effect" extends within the core element and / or the outer layer element.

[0054] If so desired, the additional layer element "incisal node emphasis" can be covered by the additional layer element "surface effects" or the additional layer element "horizontal bands".

[0055] To carry out the method according to the invention, it is particularly preferred to provide a virtual grid that is arranged on the surface of the outer layer element, which makes it possible to automatically define control points, in particular the intersections of the grid lines, which can then be used to define the position and extension of the individual additional layer elements, which in particular makes it possible to achieve a good and automatic positioning of the individual additional layer elements.

[0056] Preferably, the vertical and horizontal extensions of the virtual grid are defined by the maximum vertical and horizontal dimensions of the outer contour silhouette of the tooth element. More preferably, the grid has vertical and horizontal lines that preferably divide the tooth contour at equal distances, where the outer contour silhouette is the projected contour of the tooth element in a front view.

[0057] All additional layer elements can be arranged individually or in combination with one another. In addition to the preferred selection of material, color, color gradient, etc., the dentist or dental technician can also define the position and prominence, i.e., the dimensions, of each additional layer element. Preferably, the system automatically suggests the position and prominence of the corresponding additional layer element depending on the type of tooth element and the patient-specific size. The corresponding measurements can be particularly automatically defined, for example, by the defined size or outer dimensions of the additional layer element. It is also possible for the system to automatically suggest the design, material, etc. This can be done, for example, by automatic comparison with the natural tooth to be replaced or with other natural teeth, in particular the patient's adjacent natural teeth, based on a photograph or image.

[0058] The present invention will now be described in more detail by way of preferred embodiments with reference to the accompanying drawings. [Brief explanation of the drawings]

[0059] [Figure 1] FIG. 2 is a schematic front view of an artificial tooth element for an anterior tooth. [Figure 2] 1 is a schematic side view of an artificial tooth element for an anterior tooth. [Figure 3] FIG. 3 is a schematic front view of the anterior artificial tooth element of FIGS. 1 and 2, showing additional surfaces and curves. [Figure 4] FIG. 3 is a schematic side view of the anterior artificial tooth element of FIGS. 1 and 2, showing additional faces and curves. [Figure 5] FIG. 3 is a schematic front view of the anterior artificial tooth element of FIGS. 1 and 2, showing additional surfaces and curves. [Figure 6] FIG. 3 is a schematic side view of the anterior artificial tooth element of FIGS. 1 and 2, showing additional faces and curves. [Figure 7] FIG. 6 is an incisal view of the tooth element shown in FIG. 5. [Figure 8a] FIG. 6 is an alternative view of FIG. 5 with a different tangent angle. [Figure 8b] FIG. 6 is an alternative view of FIG. 5 with a different tangent angle. [Figure 8c] FIG. 6 is an alternative view of FIG. 5 with a different tangent angle. [Figure 9] FIG. 2 is a schematic diagram of the contours of the first and second surfaces. [Figure 10] FIG. 3 is a schematic front view of the anterior tooth element of FIGS. 1 and 2, showing additional faces and curves. [Figure 11] FIG. 11 is a schematic side view taken along section XI of FIG. [Figure 12] FIG. 2 is a schematic side view of an artificial tooth element for a lateral tooth. [Figure 13] 13 is a schematic view of the artificial tooth element for the lateral tooth shown in FIG. 12 as viewed from the incisal direction. FIG. [Figure 14] FIG. 10 is a schematic front view of a detail of a prosthetic tooth element for determining the placement of an additional layer element "incisal node accentuation." [Figure 15] FIG. 15 is a side view of the artificial tooth element shown in FIG. [Figure 16] 1A and 1B are front and side views of an artificial tooth element and an additional layer element "incisal node enhancement." [Figure 17] 1A and 1B are front and side views of the artificial tooth element and the additional layer element "colored neck." [Figure 18] FIG. 10 is a detailed view of the artificial tooth element to clarify the additional layer element "colored neck". [Figure 19] 10A and 10B are front and side views of the artificial tooth element to clarify the additional layer element "translucent effect." [Figure 20] 1A and 1B are front and side views of the artificial tooth element to clarify the additional layer element "horizontal band." [Figure 21] 1A and 1B are front and side views of the artificial tooth element to clarify the additional layer element "surface effect." [Figure 22] 1A and 1B are front and side views of an artificial tooth element with a virtual grid. [Figure 23] 1A and 1B show front and side views of an artificial tooth element with a virtual grid combined with the production of an additional layer element "translucent effect." [Figure 24] 1A and 1B show front and side views of an artificial tooth element with a virtual grid combined with the manufacture of an additional layer element "surface effect." DETAILED DESCRIPTION OF THE INVENTION

[0060] To carry out the method of the present invention, it is first necessary to define an interface between the inner core element and the outer layer element that at least partially surrounds the core element. Possible methods for defining this interface are described in detail below with reference to Figures 1-13.

[0061] 1 and 2 show a front and side view of an artificial tooth element 10 for an anterior tooth. This is the three-dimensional outer contour of the tooth element, and preferably, a corresponding data set containing data on the three-dimensional outer contour of the tooth element is opened. After aligning the tooth element 10 with a coordinate system (not shown), a first boundary curve 12 is defined, which can be defined manually and / or based on a preparation boundary or based on the tooth equator. The first boundary curve 12 defines the tooth surface 14 in the incisal direction, i.e., above the first boundary curve 12 in FIGS. 1 and 2.

[0062] The tooth flanks 14 are displaced inward toward the surface normal to create a first interface surface 16 (FIGS. 3 and 4), where a maximum displacement 17 is shown by way of example.

[0063] 3 and 4, in accordance with a preferred embodiment of the present invention, a transition surface 18 extending in an incisal direction 19 can be defined starting from the first boundary curve 12. In the illustrated embodiment, the transition surface 18 is defined in such a way that a second boundary curve 20 is defined. The second boundary curve 20 can be obtained by projecting the first boundary curve 12 a first length 22.

[0064] In the illustrated embodiment, a third boundary curve 24 is also defined (FIGS. 5 and 6). The third boundary curve 24 can be obtained by projecting the first boundary curve 12 by a second length 26.

[0065] The highest curve on the first interface surface 16 created by the first maximum displacement is defined as the incisal / occlusal first surface contour 28. The first surface contour 28 has two boundaries 30, specifically a start point and an end point. Here, the boundary 30 is defined by a tangent line 32. In FIG. 5, the angle of the tangent line 32 with respect to the tooth axis 34 is approximately 45°.

[0066] As shown in Figures 8a to 8c, the position of the boundary 30 changes as the tangent angle changes.

[0067] The course of the first surface contour 28 is shown in plan, or incisal, view (FIG. 7).

[0068] A number of nodes (FIG. 9) are defined on the surface contour. In FIG. 9, these nodes are designated as nodes 1 through 9 by way of example and are listed in a table. As indicated by the arrows, the nodes located on the first surface contour 28 are displaced in the apical direction. Connecting the displaced nodes results in a second surface contour 36.

[0069] In the illustrated embodiment, the above method steps result in a three-dimensional interface defined by the third boundary curve 24, a portion of the first interface surface 16, and the second surface contour 36 (FIGS. 10 and 11). In a preferred embodiment according to the invention, the interior of this three-dimensional surface, i.e., in the space 38, is provided with a material that is different from the volume of the artificial tooth element 10 that surrounds this space. These two volumes are defined in particular by different materials, with the internal volume 38 imitating dentin. Here, the interface between the volume forming the dentin and the surrounding volume is not identical to the corresponding interface of the associated natural tooth.

[0070] 12 and 13 show the corresponding contours of the lateral teeth, which correspond to the contours described for the protruding edges of the anterior teeth. Additionally, a central fissure 40 (FIG. 13) is shown. The line indicating the central fissure 40 has two boundary points 42, which represent the start and end of the cusp, respectively. Additionally, a cusp tip 44 is shown on the second surface contour 36. Point 46 defines the end of the cusp and the start of the next cusp.

[0071] In the three-dimensional boundary surface defined according to the above method steps, the interior volume 38 forms the inner core element, and the volume 50 surrounding the interior volume 38 forms the outer layer element.

[0072] For the placement of the additional layer element "incisal node accentuation," a vertex 54 is defined in the preferred embodiment on the silhouette curve 52, i.e., the boundary curve between the inner core element 38 and the outer layer element 50. The vertex 54 is displaced toward the incisal edge so that a point 56 is defined. The position of the silhouette curve 52 changes accordingly. Gaps 60 are formed between the silhouette curve 52 and the boundary surface 58 defined by the point 56 after the incisal edge displacement. In these gaps 60, the additional layer element "incisal node accentuation" is placed. These may be differently colored or made of different materials, as shown in particular in FIG. 16 .

[0073] 17 and 18 show an example of an additional layer element "colored neck". As can be seen from the figures, the artificial tooth element is colored in the neck region, resulting in the placement of the additional element. The additional layer element "colored neck" 62 can be at least partially located within the core element 38, as can be seen in FIG. 18. This is determined in particular by where the boundary surface 53 is located. The additional layer element "colored neck" is preferably limited by the outer contour of the outer layer element 50. Similarly, for a change in optical appearance, the additional layer element "colored neck" 62 can be partially located within the outer layer, resulting in the outer layer element 50 covering the additional layer element "colored neck" 62 with a layer, which may be thin.

[0074] A further additional layer element, shown diagrammatically in Fig. 19, is the additional layer element "translucent effect" 64. This is an additional layer element that is provided in the incisal region of the artificial tooth element within the outer layer element 50. To define the position and design of the additional layer element "translucent effect" 64, control points can be defined on the top surface of the outer layer element, which are then displaced inwards, i.e. towards the inner core element.

[0075] In a preferred embodiment, the outer boundary of the additional layer element “semi-transparent effect” represents the outer surface of the outer layer element 50 .

[0076] Another additional layer element, "horizontal band" 66, particularly shown in Figure 20, is a horizontal line located approximately in the central region of the artificial tooth element. The horizontal band preferably begins at a horizontal line 68 located approximately at the center height of the tooth element. The horizontal band 66 may be elliptical in cross section. In particular, the horizontal band 66 protrudes partially into the outer layer element 50 and is located partially within the inner partial element 38.

[0077] A further additional layer element (FIG. 21) is the additional layer element "surface effect" 70, which is arranged in the anterior region of the artificial tooth element, preferably between the core element 38 and the outer layer element 50. If there is a vertical overlap between the additional layer element "surface effect" 70 and the additional layer element "incisal node emphasis" 60, the additional layer element "surface effect" is 21 1. The additional layer element "incisal tubercle accentuation" 60 can be positioned anteriorly or posteriorly relative to the anterior incisor surface 72 shown in FIG.

[0078] For the implementation of the method according to the invention, in particular for at least partial automation, a virtual grid (FIG. 2 2 24) is preferably provided. The virtual grid comprises, in particular, horizontal lines 74 and vertical lines 76, which are equidistantly spaced. As an outer boundary, the grid has an outer contour silhouette 78 of the artificial tooth element. Nodes 80 can be defined by the contact points of the vertical and horizontal lines 74, 76 with the outer contour silhouette. Further nodes 82 (see, for example, FIG. 24) are vertical Lines and beside It can be defined by the intersection of lines 74, 76.

[0079] Using the individual nodes 80, 82, the alignment, size etc. of the individual additional layer elements can be defined and adjusted in a simple manner, especially automatically.

[0080] For example, nodes 80 placed on the silhouette 78 can be used for translucent effects by displacing individual points, as seen in FIG.

[0081] As can be seen in Figure 24, for example, node 82 can be used to define the location of the surface effect. Other nodes can be used to define the remaining additional layer elements.

Claims

1. 1. A method of operating a processing device for defining different layer elements of an artificial tooth element, comprising: a defining means is actuated to define an interface between an inner core element (38) and at least one outer layer element (50) at least partially surrounding said inner core element (38); a display means for displaying on a screen the provided selection list including a plurality of additional layer elements (60, 62, 64, 66), said plurality of additional layer elements comprising: - including incisal nodule highlighting, and / or cervical coloring, and / or translucent effects, and / or halo effects, and / or horizontal bands, and / or surface effects; and a step of operating a positioning means to spatially define and automatically position the additional layer element (60, 62, 64, 66) selected from at least one of the selection lists relative to the inner core element (38) and / or the outer layer element (50) based on anatomical features and / or auxiliary lines or auxiliary points.

2. 2. The method of claim 1, wherein the material and / or color of at least each of the additional layer elements (60, 62, 64, 66) can be selected.

3. 3. The method of claim 1 or 2, wherein when the additional layer element "incisal nodule enhancement" is selected, the additional layer element "incisal nodule enhancement" is disposed on the inner core element (38) within the region of at least one incisal nodule defined by the boundary surface, and the additional layer element at least partially covers at least one of the incisal nodules.

4. 4. The method of claim 3, wherein the additional layer element "incisal node enhancement" is at least partially disposed within the outer layer element (50).

5. 5. The method for operating a processing device according to claim 3 or 4, wherein the boundary surface of at least one of the incisal nodes is displaced in the incisal direction to form the additional layer element "incisal node emphasis", and the additional layer element "incisal node emphasis" is formed in the area between the boundary surfaces before and after the displacement, and / or the displacement is 0 to 1.0 mm.

6. 6. A method for operating a processing device according to claim 1, wherein when the additional layer element "colored neck" is selected, the material is at least partially colored in the area of ​​the outer layer element that is located at the apex relative to the boundary curve.

7. 7. A method for operating a processing device according to any one of claims 1 to 6, wherein when the additional layer element "colored neck" is selected, the outer layer element (50) is at least partially replaced by the additional layer element "colored neck" in the area located at the apex relative to the boundary curve, and / or the outer contour of the additional layer element "colored neck" is limited by the outer contour of the outer layer element (50) and displayed on the screen.

8. 8. The method for operating a processing device according to claim 1, wherein when the additional layer element "incisal / occlusal optical effect" including the additional layer element "translucent effect" and / or the additional layer element "halo effect" is selected, the additional layer element "incisal / occlusal optical effect" is arranged in the outer layer element (50) in the incisal region of the artificial tooth element.

9. 9. The method for operating a processing device according to claim 8, wherein the additional layer element "incisal / occlusal optical effect" is limited by the outer contour of the outer layer element (50) and / or, for the definition of the additional layer element "incisal / occlusal optical effect", control points defined on the surface of the outer layer element (50) are displaced apically, the displacement occurring along a normal to the surface of the outer layer element (50).

10. 10. The method for operating a processing device according to claim 8 or 9, wherein a displacement of 0 to 1 mm occurs and / or the additional layer element "incisal / occlusal optical effect" is formed in the area between the surfaces of the outer layer element (50) before and after the displacement and / or the outer contour of the additional layer element "incisal / occlusal optical effect" is limited by the outer contour of the outer layer element (50).

11. When the additional layer element "horizontal band" is selected, a horizontal centerline is defined, the additional layer element "horizontal band" is positioned between the inner core element (38) and the outer layer element (50) in the area of ​​the centerline, and the additional layer element "horizontal band" protrudes into the inner core element (38) and / or the outer layer element (50); A method for operating a processing device according to any one of claims 1 to 10, wherein said additional layer element "horizontal band" comprises an incisal / apical dimension of 0.3 to 2 mm and / or a depth of 0.2 to 1.5 mm.

12. When the additional layer element "Surface Effect" is selected, the additional layer element "Surface Effect" is placed on the boundary surface in the anterior region, and the additional layer element "Surface Effect" partially overlaps the additional layer element "Incisal Node Enhancement", 12. Method for operating a processing device according to any one of claims 1 to 11, wherein the additional layer element "surface effect" has a width of 1 to 8 mm, a height of 1 to 10 mm and a depth of 0.1 to 1 mm.

13. 13. The method of claim 12, wherein the additional layer element "surface effect" is disposed on the inner core element (38) and / or the outer layer element (50) and is limited by the outer contour of the outer layer element (50).

14. 14. A method for operating a processing device according to any one of claims 1 to 13, wherein in order to automatically define the control points, a virtual grid is applied to the surface of the outer layer element (50), the vertical and horizontal dimensions of said grid being defined by the maximum dimensions of the outer contour silhouette, said grid comprising a plurality of vertical and / or horizontal lines dividing the tooth contour at equal distances.

15. 15. The method of claim 14, wherein the intersection of the horizontal line and the vertical line defines the control point (82), and / or the control point (80) is defined at the intersection of the vertical line and / or the horizontal line with the outer contour silhouette.

Images