Dental Blanks

Abstract

To provide a dental blank capable of not only minimizing dead space by using a polygonal material part but also increasing production efficiency of a dental prosthesis.SOLUTION: A dental blank 1 according to one embodiment of the present invention comprises a plurality of circumscribed parts which are inserted into an attachment part 20 including an attachment groove 21 having a first cross-sectional shape and which abut on the inside of the attachment part. The dental blank includes a material part 10 having a second polygonal cross-sectional shape distinguished from the first shape. The circumscribed part is brought into line contact with an inside surface of the attachment part along the insertion direction of being inserted into the attachment part. A tool entry part is formed in a separation space between the attachment groove and the material part by a difference between the first shape of the attachment groove and the second shape of the material part.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a dental blank, and more particularly to a dental blank that prevents breakage of a material portion and improves productivity. [Background technology]

[0002] When teeth are lost due to fractures, damage caused by cavities, or chipping, dental restoration or prosthetic procedures are performed. Dental prosthetic procedures refer to all procedures in which artificial teeth are made to resemble natural teeth and then attached or capped after partial or total removal of teeth. Dental prosthetics are made by recreating the shape of the patient's teeth in an impression and pouring plaster over it to recreate the shape of the teeth, or by acquiring the shape of the mouth and teeth through an intra-oral scan process, and using this to design the desired teeth on a screen through a CAD design process and then processing them with automated CAD / CAM processing equipment.

[0003] Generally, in a CAD / CAM processing device, as shown in FIG. 12, a circular workpiece 91 is inserted into a mounting table 93, a fixed table 94 and the mounting table 93 are fastened with bolts 95 to fix the workpiece 91 to a jig 90, and the workpiece 91 is then machined with a processing tool 92 to produce a dental prosthesis.

[0004] Conventionally, the workpiece material 91 has a circular shape, and in order for the tool of the processing tool 92 to move for cutting without interfering with the fixed base 94 or the mounting base 93, the only option is to set the peripheral area of ​​the workpiece material 91 that abuts against the fixed base 94 or the mounting base 93 as an area that cannot be processed. Therefore, the workpiece material 91 necessarily includes a dead space that cannot be processed into a dental prosthesis, which causes a problem of low productivity of dental prostheses.

[0005] Furthermore, the workpiece 91 is fixed to the jig 90 in a state where it is in direct contact with the mounting table 93 or the fixed table 94 over a wide area along the circumference. In other words, the workpiece 91 is fixed in direct surface contact with the hard mounting table 93 or the fixed table 94, but if the tool of the processing tool 92 comes into contact with the workpiece 91 in this state, stress is instantaneously concentrated, causing a problem that the workpiece 91 may be damaged. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Korean Patent No. 10-1382382 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention is made to solve such problems, and its object is to provide a dental blank that uses a polygonal material portion to minimize dead space and improve the production efficiency of dental prostheses.

[0008] Another object of the present invention is to provide a dental blank that can protect the material part from external forces by using a guard part to prevent the material part from directly contacting an attachment part or a fixing part, thereby reducing the amount of wear of the material part due to cracks. [Means for solving the problem]

[0009] A dental blank according to one embodiment of the present invention includes a material part having a second polygonal shape in cross section that is distinct from the first shape and has a plurality of circumscribing portions that are inserted into a mounting part including a mounting groove having a first cross section and abuts against the inside of the mounting part, the circumscribing portions make line contact with the inner surface of the mounting part along the insertion direction in which the material part is inserted into the mounting part, and a tool entry portion is formed in the space between the mounting groove and the material part due to the difference in shape between the first shape of the mounting groove and the second shape of the material part.

[0010] The blank portion may be protected by a guard portion located in contact with at least one of an upper surface, a lower surface, and a side surface of the blank portion, and an opening connected to the tool entrance portion may be formed by the guard portion. The guard portion may be located surrounding the side surface of the blank portion and may have a polygonal cross-sectional shape. The mounting portion may include a mounting groove in which the blank portion is mounted and which has a circular cross-sectional shape. Effect of the Invention

[0011] The dental blank according to the present invention can prevent external forces acting on the material portion from being diffused via the polygonal material portion, thereby reducing the amount of wear on the material portion due to cracks.

[0012] In addition, the dental blank according to the present invention can reduce wear on the machining tool by forming a tool entry portion and reducing the entry load of the machining tool, can minimize dead space in the material by processing even the edge region of the material, and can increase the production efficiency of dental prostheses.

[0013] Furthermore, the dental blank according to the present invention can protect the material by mitigating stress or impact transmitted from the processing device via the guard portion, thereby preventing damage to the material. [Brief description of the drawings]

[0014] [Figure 1] 1A-1D are schematic diagrams illustrating an application of a dental blank according to an embodiment of the present invention. [Diagram 2] FIG. 1 is an exploded perspective view showing a schematic representation of a dental blank according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a perspective view showing a schematic view of a blank portion of a dental blank according to an embodiment of the present invention. [Figure 4] FIG. 2 is a plan view showing a schematic diagram of a blank and a mounting groove of a dental blank according to an embodiment of the present invention. [Diagram 5] 2 is a cross-sectional view showing a schematic view of a blank and a mounting groove of a dental blank according to an embodiment of the present invention; FIG. [Figure 6] FIG. 2 is a plan view showing a schematic diagram of a blank portion, a guard portion, and a mounting groove of a dental blank according to an embodiment of the present invention. [Figure 7] FIG. 2 is a plan view showing a schematic diagram of a blank portion, a guard portion, and a mounting groove of a dental blank according to an embodiment of the present invention. [Figure 8] 2 is a cross-sectional view showing a schematic view of a blank portion, a guard portion, and a mounting groove of a dental blank according to an embodiment of the present invention. FIG. [Figure 9] FIG. 2 is a schematic plan view of a blank portion and a guard portion of a dental blank according to an embodiment of the present invention; [Figure 10]2 is a cross-sectional view showing a schematic of a blank portion and a guard portion of a dental blank according to an embodiment of the present invention; FIG. [Figure 11] 2 is a cross-sectional view showing a schematic of a blank portion and a guard portion of a dental blank according to an embodiment of the present invention; FIG. [Figure 12] FIG. 1 is a perspective view showing a machining jig and a workpiece of a conventional machining apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The advantages, features and methods of achieving the present invention will become more apparent with reference to the following detailed description of the embodiments taken in conjunction with the accompanying drawings.

[0016] However, the present invention is not limited to the embodiments disclosed below, and may be realized in various different forms. However, the embodiments are provided merely to complete the disclosure of the present invention and to fully convey the scope of the invention to those skilled in the art to which the present invention pertains. The present invention is defined only by the scope of the claims.

[0017] Hereinafter, a dental blank according to an embodiment of the present invention will be described in detail with reference to Figures 1 to 11. In describing the present invention, detailed descriptions of related known functions or configurations will be omitted in order not to obscure the gist of the present invention.

[0018] FIG. 1 is a diagram showing an example of application of a dental blank according to one embodiment of the present invention; FIG. 2 is an exploded perspective view showing a dental blank according to one embodiment of the present invention; FIG. 3 is an perspective view showing a material portion of a dental blank according to one embodiment of the present invention; FIG. 4 is a plan view showing a blank portion and a mounting groove of a dental blank according to one embodiment of the present invention; FIG. 5 is a cross-sectional view showing a blank portion and a mounting groove of a dental blank according to one embodiment of the present invention; FIGS. 6 and 7 are plan views showing a blank portion, a guard portion and a mounting groove of a dental blank according to one embodiment of the present invention; FIG. 8 is a cross-sectional view showing a blank portion, a guard portion and a mounting groove of a dental blank according to one embodiment of the present invention; FIG. 9 is a plan view showing a blank portion and a guard portion of a dental blank according to one embodiment of the present invention; and FIGS. 10 and 11 are cross-sectional views showing a blank portion and a guard portion of a dental blank according to one embodiment of the present invention.

[0019] 1 to 3, the dental blank 1 can be applied to an artificial tooth processing device, which can be, for example, a CAD (computer-aided design) / CAM (computer-aided manufacturing) processing device 80. The CAD / CAM processing device 80 can process the dental blank 1 by grinding, milling, cutting, etc. The dental blank 1 can include a material part 10, a mounting part 20, and a fixing part 40.

[0020] The material part 10 may be made of at least one of glass or glass-ceramic, polymer infiltrated glass, composite resin or hybrid material, unsintered or separately sintered or a densely-sintered ceramic, metal or metal alloy. The material part 10 has characteristics such as high strength, thermal stability, and high corrosion resistance, and may be white or colored alone, or a mixture of white and colored.

[0021] The material part 10 can be processed into a dental prosthesis 11 by a CAD / CAM processing device 80. For example, when a dental blank 1 is mounted on the CAD / CAM processing device 80, a processing tool 81 of the processing device 80 operates based on data converted via the external surface coordinates of a tooth model obtained through scanning, and the material part 10 of the dental blank 1 can be cut and processed into a dental prosthesis 11.

[0022] Here, the dental prosthesis 11 may refer to a dental restoration, filling, or casting that can regenerate a tooth portion or replace a lost tooth when a tooth is lost due to a tooth fracture, damage caused by tooth decay, or loss, etc. For example, the dental prosthesis 11 may be a crown, inlay, onlay, veneer, coping, pontic, laminate, or the like for various teeth such as molars and canines.

[0023] The material part 10 may further be processed to have a connection bar 12 connected to the dental prosthesis 11. The connection bar 12 can interconnect the inside of the material part 10 and the processed dental prosthesis 11, and can play a role in easily separating the dental prosthesis 11 from the material part 10. The material part 10 may refer to a body to be machined by the CAD / CAM processing device 80, or may refer to a body including the processed dental prosthesis 11.

[0024] The mounting part 20 is connected to the CAD / CAM processing device 80, and may include a mounting groove 21, a coupling groove 22, and a coupling hole 23. The mounting groove 21 may have a circular groove shape recessed toward the inside of the mounting part 20. The mounting groove 21 may be a space in which the material part 10 is mounted. When the material part 10 is positioned in the mounting groove 21, the circumference of the inner surface of the mounting groove 21 may abut against an outer corner of the material part 10.

[0025] The coupling groove 22 may have a groove shape recessed toward the inside of the mounting part 20. The coupling groove 22 may be a space in which the fixing part 40 is mounted. The coupling hole 23 may have a hole shape provided toward the inside of the mounting part 20.

[0026] The fixing part 40 may include a fastener 41 and a fastening hole 42. The fastener 41 is a fastening device such as a bolt, and may be connected to the coupling hole 23 in a state where it is inserted into the fastening hole 42 passing through the fixing part 40.

[0027] When the material part 10 and the fixing part 40 are mounted in the mounting groove 21 and the coupling groove 22, respectively, the fastener 41 can pass through the fastening hole 42 and couple with the coupling hole 23. In other words, with the fixing part 40 in contact with a part of the material part 10, the fastener 41 is bolted to the coupling hole 23, so that the fixing part 40 can fix the material part 10 to the mounting part 20. The structure of the material part 10 of the dental blank 1 will now be described in more detail with reference to FIGS.

[0028] 4 and 5, the blank 10 may have a polygonal cross section and may include a plurality of circumscribing portions 13 located on the periphery. The circumscribing portions 13 may be formed corresponding to the polygonal corners of the blank 10. For example, if the blank 10 is octagonal, there may be eight circumscribing portions 13.

[0029] When the blank 10 is received in the mounting groove 21, the circumscribing portions 13a, 13b, 13c, and 13d can each abut against the inside of the mounting groove 21. Since the blank 10 has a polygonal shape, the circumscribing portions 13a, 13b, 13c, and 13d can each make line contact with the inner surface of the mounting groove 21 along the insertion direction in which the blank 10 is inserted into the mounting groove 21. In other words, when the blank 10 is inserted into the mounting groove 21, as shown in the enlarged circle in FIG. 5, a line contact portion 14 that makes line contact with the inner surface of the mounting groove 21 and the circumscribing portion 13a along the z-axis direction can be formed.

[0030] Conventionally, the workpiece is disk-shaped, and when it is placed on the mounting table, the entire circumference of the workpiece is fixed in surface contact with the inner surface of the mounting table. When an external force is applied to the workpiece in this state, the external force is diffused over the entire workpiece along the wide surface contact area between the workpiece and the hard mounting table, and the entire area of ​​the workpiece may be damaged.

[0031] On the other hand, the material part 10 of the present invention has a polygonal shape, and when it is accommodated in the mounting groove 21, the circumscribing part 13 and the mounting groove 21 are in line contact with each other. In other words, a relatively narrow line contact part 14 is formed between the material part 10 and the mounting groove 21, so that even if an external force is generated in the material part 10, the force does not spread throughout the material part 10. Therefore, the material part 10 of the present invention can be prevented from being broken as a whole, and the amount of wear of the material part 10 due to cracks can be reduced.

[0032] Meanwhile, when the blank part 10 is accommodated in the mounting groove 21, a tool entrance part 15 may be formed between the mounting groove 21 and the circumscribing part 13. The tool entrance part 15 may be a space between the polygonal blank part 10 and the circular mounting groove 21. For example, the tool entrance part 15a may be a space having a circular arc side formed between the pair of circumscribing parts 13a, 13b and the inner surface of the mounting groove 21. When the blank part 10 is octagonal, eight tool entrance parts 15 may be formed. The tool entrance part 15 may be a space into which a processing tool 81 of a processing device 80 enters or in which a processing tool 81 is accommodated.

[0033] In the conventional method, a circular workpiece is in close contact with a circular mounting base, and no space is formed between them, so the processing tool starts processing the workpiece from above, but when the processing tool comes into contact with the top of the workpiece, stress is concentrated at the contact point, causing cracks and potentially damaging the workpiece. In addition, in the conventional method, the area where the workpiece contacts the mounting base or fixing base and the surrounding area are set as dead spaces where processing is not possible, resulting in low productivity of dental prostheses.

[0034] In contrast, the dental blank 1 proposed in the present invention forms the tool entry section 15 between the polygonal material part 10 and the circular mounting groove 21, and starts processing with the processing tool 81 entering the side surface of the material part 10, so that the entry load of the processing tool 81 is low and stress concentration phenomenon between the processing material 10 and the processing tool 81 can be prevented in advance. In addition, when the processing tool 81 starts processing at the tool entry section 15, it is possible to process even the edge region of the material part 10, so that the dead space of the material part 10 can be minimized and the production efficiency of the dental prosthesis 11 can be improved. In addition, when processing the dental prosthesis 11 on the edge part of the material part 10, the resistance force generated in the processing tool 81 is smaller than when forming the dental prosthesis 11 in the center part of the material part 10, so that the wear of the processing tool 81 can be reduced and the production speed of the dental prosthesis 11 can be improved.

[0035] The cross section of the material 10 may be a polygonal shape having 4 to 32 corners, and preferably has an octagonal cross section. Here, the octagon does not mean a mathematically perfect octagon, but means one that can be recognized as an octagon at a glance overall, and all are used with the same meaning in the present invention.

[0036] The diameter of the material part 10, which is the longest diameter of the octagonal cross section of the material part 10, can be 50 mm or more, preferably 80 mm to 150 mm. The thickness of the material part 10, i.e., the height in the z-axis direction, can be 5 mm or more. The thickness of the material part 10 can be smaller than the diameter of the material part 10.

[0037] 6 to 11, the material part 10 may include a guard part 30. The guard part 30 may be located in contact with one side of the material part 10. The guard part 30 is made of plastic, rubber, silicone, etc., and can protect the material part 10 by mitigating stress, impact, etc. transmitted from the processing device 80. The guard part 30 can be attached to and detached from the material part 10 and can be reused.

[0038] The guard part 30 may have an opening 31 formed on one side. The opening 31 may be positioned opposite the tool entrance part 15, so that even if machining is started with the machining tool 81 positioned at the tool entrance part 15, the material part 10 can be machined directly through the opening 31.

[0039] 6, the guard part 30 may have a circular shape, surround the side surface of the material part 10, and be located between the mounting groove 21 and the material part 10. The outer side of the guard part 30 may be in surface contact with the mounting groove 21, and the inner side of the guard part may be in line contact with the polygonal shape of the material part 10. In this case, the guard part 30 may protect the material part 10 from external forces transmitted from the processing device 80.

[0040] 7, the guard part 30 can correspond to the polygonal shape of the material part 10. For example, if the material part 10 is octagonal, the cross section of the guard part 30 can also be octagonal. In this case, the guard part 30 is positioned surrounding the side surface of the material part 10, so that it is possible to attenuate processing vibrations generated when the material part 10 is processed and prevent the processing vibrations from diffusing to the processing device 80.

[0041] 8, the guard part 30 can be positioned so as to surround a part of the side surface of the material part 10. That is, the thickness of the guard part 30, i.e., the height in the z-axis direction, can be smaller than the thickness of the material part 10. In this case, when the machining tool 81 moves to cut the material part 10, interference between the guard part 30 and the machining tool 81 can be prevented.

[0042] 9 and 10, the guard part 30 may be located on the upper surface of the material part 10. In this case, the guard part 30 is located between the material part 10 and the fixing part 40, and can protect the material part 10 from fastening pressure that may be generated when the fixing part 40 is bolted to the mounting part 20.

[0043] 11, the guard part 30 may be located on the underside of the material part 10. In this case, the guard part 30 is located between the material part 10 and the mounting part 20, and can absorb stress generated when the processing tool 81 processes the material part 10 from the underside of the material part 10, thereby providing a cushioning effect to the material part 10.

[0044] In summary, the guard part 30 can abut against one side of the material part 10 to protect the material part 10, and can be located on the side, bottom or top of the material part 10. The dental blank 1 proposed in the present invention includes the guard part 30 to prevent the material part 10 from coming into direct contact with the mounting part 20 or the fixing part 40, thereby protecting the material part 10 from external forces and preventing damage in advance.

[0045] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims should also fall within the scope of the present invention. [Explanation of symbols]

[0046] 1 dental blank 10 Materials Section 11 Dental prostheses 12 Connecting bar 13 External part 14 Line contact 15 Tool entry section 20 Mounting part 21 Mounting groove 22 Connection groove 23 Bonding Hole 30 Guard section 31 Opening 40 Fixed part 41 Fasteners 42 Concluding Hole 80 Processing equipment 81 Processing tools

Claims

1. A dental blank including a mounting portion including a mounting groove, and a blank portion that is inserted into the mounting portion in a predetermined insertion direction and has a plurality of circumferential contact portions that abut against an inner side of the mounting portion, In a cross section perpendicular to the insertion direction, the mounting groove has a circular hole shape, and the material portion has a polygonal prism shape in cross section, A configuration in which an edge of the prismatic side surface and an inner side surface of the hole-like shape are in line contact, A dental blank, characterized in that a tool entry portion is formed in a space between the mounting groove formed between the circumferential contact portion and the material portion.

2. The material part is The material portion is protected by a guard portion located in contact with at least one of the upper surface, the lower surface, and the side surface, 2. The dental blank of claim 1, wherein the guard portion defines an opening that is continuous with the tool entry portion.

3. The dental blank according to claim 2 , wherein the guard portion is positioned to surround a side surface of the material portion.

4. 4. The dental blank of claim 3, wherein the guard portion has a polygonal cross-sectional shape.

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