DENTAL BLOCK FORMING A BLANK FOR A PARTIAL PROSTHESIS, DENTAL PARTIAL PROSTHESIS AND METHOD OF MANUFACTURING A DENTAL PARTIAL PROSTHESIS

Abstract

The present invention relates to a dental blank, in particular a parallelepipedal block, having an upper surface and a lower surface, which is composed of a flesh-coloured material and a tooth-coloured material. The flesh-coloured material and the tooth-coloured material are bonded together. The interface between the materials with elevations and depressions formed in or at the interface extends through an optionally curved plane, which plane is parallel to or oblique to at least a portion of the surfaces of the blank.

Claims

1. A block comprising an upper and a lower surface, wherein the block comprises a flesh-coloured material and a tooth-coloured material wherein the flesh-coloured material and the tooth-coloured material are connected to each other and wherein an interface between the materials with elevations and depressions formed in or at the interface extends through an optionally curved plane, which plane is parallel to or oblique to at least part of the upper and lower surfaces of the blank, wherein vertex lines of the elevations and depressions, as viewed in plan view of the interface, form substantially straight lines and are substantially parallel to each other.

2. The block according to claim 1, wherein the vertex lines of the elevations and depressions run parallel or substantially parallel to the interface.

3. The block according to claim 1, wherein the vertex lines are at a constant distance from one another, or wherein the distances between vertex lines as viewed in plan view of the interface are different, gradually increasing and/or decreasing.

4. The block according to claim 1, wherein the vertex lines, viewed over the block are arranged in a fan-shape or diverge from one another.

5. The block according to claim 1, wherein the tooth-coloured material, and/or the flesh-coloured material, comprises a colour gradient and/or is continuously and increasingly transparent with increasing distance from the interface between the materials.

6. A dental blank with an upper and a lower surface, wherein the blank comprises a flesh-coloured material and a tooth-coloured material, wherein the flesh-coloured material and the tooth-coloured material are connected to each other and wherein an interface between the materials with elevations and depressions formed in or at the interface extends through an optionally curved plane, which plane is parallel to or oblique to at least part of the upper and lower surfaces of the blank, wherein vertex lines of the elevations and depressions form substantially straight lines when viewed in plan view of the interface and are substantially parallel to each other.

7. The dental blank according to claim 6, wherein the vertex lines of the elevations and depressions run parallel or substantially parallel to the interface and/or extend across the blank.

8. A dental partial prosthesis prepared from a block according to claim 1.

9. A method for manufacturing a dental partial prosthesis using a CAD/CAM device from a dental blank or block which is manufactured with an upper and a lower surface and is constructed from a flesh-coloured material and a tooth-coloured material, wherein the flesh-coloured material and the tooth-coloured material are bonded together and wherein the interface between the materials with elevations and depressions formed in the interface extends through a plane, which plane is parallel or curved or oblique to one of the disc surfaces of the dental blank or block, wherein an area is reserved in the dental blank or block for at least one partial prosthesis, which area extends over one or more elevations and depressions, and wherein vertex lines of the elevations and depressions each form substantially straight lines and are substantially parallel to each other.

10. The method for manufacturing a dental partial prosthesis according to claim 9, wherein the vertex lines of the elevations and depressions are parallel or substantially parallel to the interface.

11. The method for manufacturing a dental partial prosthesis according to claim 9, wherein a plurality of partial prostheses for different patients, are produced from the dental blank or block, after scanning, virtual creation of the prosthesis and virtual positioning in the blank.

12. The method of manufacturing a dental partial prosthesis according to claim 9, wherein the block has reference points for positioning in the CAD/CAM device and/or an individual identification mark.

13. The method of manufacturing a dental partial prosthesis according to claim 12, wherein the individual identification mark comprises a QR code or an RFID tag.

14. The method for manufacturing a dental partial prosthesis according to claim 9, wherein the CAD/CAM device fixes the partial prosthesis with regard to a spatial shape thereof, and has a control device which, depending on the desired size and/or tooth width, positions the partial prosthesis in the blank, and also suggests and fixes, if necessary after user intervention, the individual tooth shape, the rotation and/or the angulation of the teeth.

15. The method for manufacturing a dental partial prosthesis according to claim 14, wherein the control device stores the position of a manufactured prosthesis for each blank and determines a blank and/or the positioning on a blank for new partial prostheses to be manufactured, by a “nesting” method, in order to achieve maximum use of raw materials.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Further advantages, details and features result from the following description of several embodiments of the invention on the basis of the drawings.

[0052] FIG. 1A shows a schematic section through a block according to the invention in perspective view in a first embodiment with possible placements of various virtual partial prostheses;

[0053] FIG. 1B shows a schematic section through a block according to the invention in perspective view in a further embodiment;

[0054] FIG. 2A shows a schematic representations of a further embodiment of the inventive interface between the tooth-coloured and the flesh-coloured material and possible positioning of teeth of different sizes in a disc-shaped blank;

[0055] FIG. 2B shows a schematic representations of a first embodiment of a block according to the invention in top view and possible positioning of a partial prosthesis;

[0056] FIG. 3A shows a schematic representations of a further embodiment of the inventive interface between the tooth-coloured and the flesh-coloured material and possible positioning of teeth of different sizes in a disc-shaped blank;

[0057] FIG. 3B shows a schematic representations of a first embodiment of a block according to the invention in top view and possible positioning of a partial prosthesis;

[0058] FIG. 4A shows a schematic representations of a further embodiment of the inventive interface between the tooth-coloured and the flesh-coloured material and possible positioning of teeth of different sizes in a disc-shaped blank;

[0059] FIG. 4B shows a schematic representations of a first embodiment of a block according to the invention in top view and possible positioning of a partial prosthesis;

[0060] FIG. 5A shows a schematic section through a tooth/gingival part prepared according to the invention, consisting of a gum-coloured and a tooth-coloured material in a first embodiment;

[0061] FIG. 5B shows a schematic section through a partial prosthesis part or tooth/gingival part prepared according to the invention, consisting of a gum-coloured and a tooth-coloured material in a further embodiment.

DETAILED DESCRIPTION

[0062] FIGS. 1A and 1B show a schematic section through a block or blank according to the invention in perspective view. FIG. 1A shows possible placements of several virtual tooth/gingiva parts 1. The teeth 2, in particular connected by joints 6, consist of tooth-coloured material 4 and the prosthesis base 8 of flesh-coloured material 10. The two materials are intensively bonded to each other at their interface 12, in particular polymerised or bonded to each other.

[0063] The tooth/gingiva parts 1 are made from a two-colour block or blank. The plane 13 passing through the interface 12 between the two materials is perpendicular to the height, and thus horizontal in FIGS. 1A and 1B. In FIG. 1A the plane 13 is shown at a side view.

[0064] FIG. 1B shows the arrangement of the interface 12 in a block according to the invention with the vertex lines 11 according to the invention in perspective view. Here, the three-dimensional embodiment of the flesh-coloured material 10 is shown at the interface between materials 4 and 10.

[0065] In the top view, the plane 13 runs as a sectional plane through the interface 12 according to the invention between the tooth-coloured material 4 and the flesh-coloured material 10. Even though this is shown in FIG. 1A, the plane 13 and thus the general course of the interface 12 between the two materials does not have to run horizontally in the blank. Rather, the plane 13 can also run at an angle or be curved. The blank can be block-shaped or round. In the block-shaped embodiment, the plane 13 passing through the interface 12 between the two materials runs horizontally in the flat block. In another embodiment, a plane 13 passing through the interface 12 and running obliquely in the blank is realised and thus also an interface 12 running obliquely in the blank.

[0066] As shown in FIG. 1B, the interface 12 between the materials of the block, as viewed along the plane 13 and perpendicular to the vertex lines 11 according to the invention, has a succession of elevations 32 and depressions 34. The vertex lines 11 of a depression 34 or an elevation 32 each form a line, in particular a straight line, which is parallel or at least approximately parallel to the interface. However, a slight inclination towards or away from the boundary surface is also possible. This inclination can be 0.5 degrees, 1 degree, 2 degrees, 4 degrees, 7 degrees, 10 degrees, 15 degrees, 20 degrees or any value between 0 degrees and 30 degrees.

[0067] Furthermore, the individual vertex lines 11 of the elevations 32 and depressions 34 each run essentially parallel to each other. The vertex lines 11 protrude from the plane. The vertex lines 11 of the elevations 32 extend to the figures above level 13 and the vertex lines 11 of the depressions 34 below the plane 13.

[0068] The tooth-coloured material 4 has exactly the negative shape of the flesh-coloured material 10 at the interface 12 between the two materials. Thus, the interface 12 between the materials has linear elevations 32 and depressions 34 and the two materials interlock. Between these extend transitions which form sloping surfaces or, as it were, slopes. In cross-section, which is perpendicular to the linear elevations 32 and depressions 34 and also perpendicular to the plane 13, the interface 12 between the two materials thus has a curved shape. This shape can also be described as chain-line shaped.

[0069] If the blank is viewed in cross-section through both materials as shown in FIG. 1B, i.e., perpendicular to the plane of the interface 12, whereby it is assumed here that the flesh-coloured material 10 is at the bottom and the tooth-coloured material 4 is at the top and which cross-section runs perpendicular to the vertex lines 11, the elevations 32 and depressions 34 of the flesh-coloured material 10 at the interface 12 are not symmetrical when reflected on the plane 13. On the contrary, the elevations 32 are rather pointed and the depressions 34 are rather rounded. This design of the interface 12 corresponds to the human gum line and can be compared to a string of Us 30.

[0070] The interlocking supports the strength and resistance of the connection of the tooth-coloured material 4 with the flesh-coloured material 10, in particular in the case of a connection via an adhesive joint, against forces acting thereon, for example during the further processing of the blank, but also during the everyday use of the final partial prosthesis. The asymmetry of the interface, on the other hand, allows easy fabrication of tooth/gingiva parts 1, which have a particularly natural appearance, since the tapering elevations 32 of the flesh-coloured material 10 automatically resemble the natural course of the gums in the interdental region. The rounded depressions 34 of the flesh-coloured material 10, i.e., the rounded elevations of the tooth-coloured material 4 in the negative form, provide the natural tooth shape. In order to achieve a natural appearance, the tooth/gingiva parts 1 thus only have to be milled out of the blank at suitable points, i.e., at points which are identified by the control device of the CAD/CAM device as suitable and preferably also the most space-saving. As a final finishing operation, only a finishing milling of the gingival margin at the transition area between flesh-coloured and tooth-coloured material 4, 10, respectively, is necessary.

[0071] FIGS. 2A and 2B, 3A and 3B as well as 4A and 4B show schematic representations of several embodiments of a blank according to the invention, namely a disk in FIGS. 2A, 3A and 4A and a block in FIGS. 2B, 3B and 4B. The representation in these figures is intended to show the interface 12 between materials 4 and 10 (cf. FIGS. 1A and 1B). Several parallel lines are shown, each of which runs across the disk or the block. Dashed lines correspond to vertices or vertex lines 11 of the recesses 34—this position then corresponds to the centre of a tooth of the manufactured partial prosthesis. Solid lines correspond to vertices or vertex lines 11 of elevations 32, which correspond to the interdental spaces, the papillae, i.e. in the partial prosthesis the junctions 6 between the individual teeth 2. Both figures refer to the flesh-coloured material 10.

[0072] In addition, possible positions of teeth and tooth arrangements 2 are drawn in FIGS. 2A and 2B. These correspond to the teeth of the partial prostheses which are to be milled out of the block according to FIG. 2B and the disc according to FIG. 2A later.

[0073] Another particular advantage of a disc-shaped blank with a diameter of e.g., just under 100 mm is that a large number of positions are available for the arrangement of partial dentures. Such a blank can also be used for considerably more partial dentures than shown in FIG. 2A. The apex lines of the elevations and depressions, which extend completely and uninterruptedly across the blank, make it possible to arrange the partial dentures in any desired distribution, even, as shown in FIG. 2A, adjacent to the edge of the disc-shaped blank.

[0074] FIGS. 2A and 2B shows a waveform in the interface 12 between materials 4 and 10, in which the distances between the vertex lines 11, which are close to the centre of the blank, are further apart than the distances between vertex lines 11 closer to the edge of the blank. As a result, large tooth sizes can be realized here near the centre of the blank and smaller tooth sizes near the edge of the blank. A smaller line spacing corresponds to a less high waveform and a larger one to a higher waveform.

[0075] If the teeth of a partial prosthesis or a tooth/gingiva part are to be large, the partial prosthesis is positioned in the middle, and if small, on the left or right edge of the blank.

[0076] It is understood that the exact shape of the chain line or wave, i.e. the shape of the slopes between the elevations and depressions, can also be varied at will, so that bulkier or slimmer teeth can be realized if necessary.

[0077] It is also possible to vary the shape of these oblique areas or slopes along the vertex lines 11. The choice of the position of the teeth on the vertex lines 11 then determines the shape of the individual tooth or teeth of the partial prosthesis in question.

[0078] Even though only premolars and molars forming the partial prosthesis are shown in FIGS. 2A to 4B, it is understood that partial prostheses comprising incisors and/or canines can equally be produced, in a curved course of the tooth arrangement corresponding to the human dental arch.

[0079] The embodiment according to FIGS. 3A and 3B differs from that according to FIGS. 2A and 2B only in the distribution of the lines. Here the distances between the vertex lines 11, which are close to the centre of the blank, are closer together than the distances between vertex lines 11 closer to the edge of the blank. In this embodiment, small tooth sizes are provided in the centre area of the blank and large tooth sizes are provided at the left or right edge of the blank.

[0080] The embodiment according to FIGS. 4A and 4B differs from that according to FIGS. 2A and 2B as well as 3A and 3B also in the distribution of the lines. Here the distances between the vertex lines 11 further to the left in the blank are smaller than the distances between vertex lines 11 further to the right. Accordingly, small tooth sizes can be arranged in the left area of the blank and large tooth sizes in the right area of the blank.

[0081] Instead of the linear increase or decrease of the distance between the vertex lines 11, as shown here, a logarithmic or also an irregular or arbitrary increase/decrease of the line distances is also possible in order to meet special requirements.

[0082] Furthermore, it is also possible to let the vertex line array diverge over your course. The deviation from parallelism can take 0.5 degrees, 1 degree, 2, degrees, 4 degrees, 7 degrees, 10 degrees, 15 degrees, 20 degrees or any value between 0 degrees and 30 degrees for adjacent vertex lines.

[0083] Nor is it necessary that the vertex lines 11 run exactly straight. The course may have a ripple or other change of direction, both in the direction of the adjacent vertex lines 11 and in the direction of height. This allows in a simple way variations in the size of the tooth/gingiva parts 1 to be produced and in particular irregular variations in tooth sizes, for example an unusually small tooth between normally large teeth, or vice versa. Such a sequence of shapes is sometimes also found in natural teeth.

[0084] The blocks according to the invention can be manufactured in different sizes in order to achieve a finer adaptability of dimensioning. Blocks in sizes “L” can be made for large tooth/gingiva parts, “M” for average sized tooth/gingiva parts and “S” for small tooth/gingiva parts.

[0085] In FIGS. 2B, 3B and 4B a holder 36 is shown, which is used for clamping the block according to the invention in the clamping device of the CAM device. This holder 36 can, for example, be glued to the block according to the invention.

[0086] A screw connection of the holder 36 on the block, a form-fitting plug connection or a single-piece design of the holder 36 and the block is also possible. The holder 36 may, for example, be made of flesh-coloured and/or tooth-coloured material, of another plastic or also of metal and may be adapted in its shape to the requirements of the clamping device of the respective CAM device.

[0087] It is also possible that the block be manufactured with a structure rotated by e.g., 45° compared to the embodiments shown. The vertex lines 11 are then not parallel to a side surface of the block, but diagonally or obliquely and essentially parallel to the interface of the block.

[0088] It is understood that for the production of a cuboid block, as shown in FIGS. 2B, 3B and 4B, it is not necessary to mill it from a disc-shaped blank, as shown in FIGS. 2A, 3A and 4A. Rather, the block can be produced directly in cuboid form.

[0089] FIGS. 5A and 5B show a schematic section through a tooth/gingiva part 1 milled from the blank or block according to the invention. The teeth 2 consist of tooth-coloured material 4 and the gingiva part 8 of flesh-coloured material 10. The two materials are intensively bonded to each other, in particular polymerised or bonded to each other, at their interface 12 in advance, i.e., already in the blank. FIG. 5A shows a multi-part, here a four-part, tooth/gingiva part. The teeth 2 made of tooth-coloured material 4 are connected to each other at connection points 6.

[0090] FIG. 5B shows a one-piece tooth/gingiva part, a so-called single tooth prosthesis. The tooth/gingival parts 1 are prepared from a flat, possibly disc-shaped, two-tone block or blank, as shown in FIGS. 1 to 4.

[0091] The terms “about” and “substantially” are intended to include the degree of error or uncertainty associated with measurement of the particular quantity or shape as one of ordinary skill in the art would understand.

[0092] Some embodiments may involve the use of one or more electronic or computing devices. Such devices typically include a processor, processing device, or controller, such as a general purpose central processing unit (CPU), a graphics processing unit (GPU), a microcontroller, a reduced instruction set computer (RISC) processor, an application specific integrated circuit (ASIC), a programmable logic circuit (PLC), a field programmable gate array (FPGA), a digital signal processing (DSP) device, a personal computer microprocessor, and/or any other circuit or processing device capable of executing the functions described herein. The methods described herein may be encoded as executable instructions embodied in a computer readable medium, including, without limitation, a storage device and/or a memory device. Such instructions, when executed by a processing device, cause the processing device to perform at least a portion of the methods described herein. The above examples are exemplary only, and thus are not intended to limit in any way the definition and/or meaning of the term processor and processing device.

[0093] Where used herein, the term “non-transitory” is a limitation on the computer-readable storage medium itself—that is, it is tangible and not a signal—as opposed to a limitation on the persistence of data storage. A non-transitory computer-readable storage medium does not necessarily store information permanently. Random access memory (which may be volatile, non-volatile, dynamic, static, etc.), read-only memory, flash memory, memory caches, or any other tangible, computer-readable storage medium, whether synchronous or asynchronous, embodies it.

[0094] Although the invention is illustrated above, partly with reference to some preferred embodiments, it must be understood that numerous modifications and combinations of different features of the embodiments can be made. All of these modifications lie within the scope of the appended claims.