Dental block and method for producing dental block

Abstract

This dental block includes a pin section and a block section. The dental block is characterized by the following: the dental block contains a thermoplastic resin; the pin section and the block section are integrally formed; and product identification information is printed on the pin section.

Description

Dental block and method of manufacturing dental block

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to dental blocks and methods for making dental blocks.

[0002] Conventionally, dental blocks have been made using a metal base and thermosetting resin, and dental blocks made using this dental block material have been machined using CAD / CAM. CAD / CAM machining is a process that combines CAD (Computer Aided Design), a system that uses a computer to design structures, and CAM (Computer Aided Manufacturing), a system that converts the shape data obtained by CAD into data for machining. However, dental blocks made using thermosetting resin have been difficult to machine using CAD / CAM. Another issue is that CAD / CAM-machined products obtained from dental blocks made using this dental block material are hard but brittle and easily chipped.

[0003] To address these issues, Patent Document 1 discloses a dental block made of a thermoplastic resin having a Vickers hardness, flexural strength, and flexural modulus within a predetermined range. It also discloses a dental block having a block portion and a pin portion, the block portion and the pin portion being made of the dental block material.

[0004] Japanese Patent Application Laid-Open No. 2022-119683

[0005] A dental prosthesis can be obtained by CAD / CAM processing the dental block disclosed in Patent Document 1. However, the present inventors have found that when a dental prosthesis is obtained from a dental block using CAD / CAM processing, there is no traceability of the product after the dental prosthesis is applied to a patient.

[0006] An object of the present disclosure is to provide a dental block with excellent product traceability and a method for manufacturing the same.

[0007] The present disclosure relates to the following: [1] A dental block having a pin portion and a block portion, wherein the dental block contains a thermoplastic resin, the pin portion and the block portion are integrally molded, and product identification information is printed on the pin portion. [2] The dental block according to [1], wherein the pin portion has a stem and a head, and the product identification information is printed on at least one of the stem and the head. [3] The dental block according to [2], wherein the product identification information is printed on a side surface of the stem. [4] The dental block according to [2] or [3], wherein the head is cylindrical, and the product identification information is printed on a side surface of the head. [5] The dental block according to any of [1] to [4], wherein the product identification information includes one or more selected from the group consisting of the manufacturing date of the dental block, the manufacturing location of the dental block, the manufacturer of the dental block, the manufacturing lot number of the dental block, and the product name of the dental block. [6] The dental block according to any one of [1] to [5], further comprising an inorganic filler, wherein the content of the inorganic filler in the dental block is 5 to 30 mass%. [7] The dental block according to any one of [1] to [6], wherein the thermoplastic resin comprises one or more thermoplastic resins selected from the group consisting of polyether ether ketone, polyether ketone ketone, polycarbonate, and modified polyphenylene ether. [8] A method for manufacturing the dental block according to any one of [1] to [7], comprising: a molding step of integrally molding the pin portion and the block portion; and a printing step of printing the product identification information on the pin portion by laser marking.

[0008] The present disclosure provides a dental block with excellent product traceability and a method for manufacturing the same.

[0009] 1 is a perspective view of a dental block according to one embodiment of the present disclosure; 2 is a perspective view of a dental block according to one embodiment of the present disclosure; 3 is a perspective view of an embodiment of a stem portion; 4 is a photograph (a photograph substituted for drawing) of a dental block according to Example 1; 5 is a photograph (a photograph substituted for drawing) of a dental block according to Example 2; 6 is a photograph (a photograph substituted for drawing) of a dental block according to Examples 3 and 4; 7 is a photograph (a photograph substituted for drawing) of a dental block according to Reference Example 1; 8 is a photograph (a photograph substituted for drawing) of a dental block according to Comparative Example 1;

[0010] The present disclosure will be described below based on specific embodiments. In this specification, when a numerical range is described with a lower limit and an upper limit separately, the numerical range can be a combination of any lower limit and any upper limit. In this disclosure, a numerical range expressed using "A to B" means a numerical range that includes the lower and upper limits, which are the endpoints.

[0011] As used herein, dental blocks refer to blocks containing resin for use in CAD / CAM processing. By subjecting dental blocks to CAD / CAM processing, dental prostheses called dental block molded products (also called crowns) can be manufactured. These dental block molded products can be used, for example, to treat caries in patients by drilling out the decayed portion and then placing the dental block molded product in the area of ​​the tooth to be restored, and are therefore primarily used for dental treatment. As used herein, dental block materials refer to materials used in the production of dental blocks. Dental block materials can also be referred to as dental block material compositions.

[0012] As described above, dental prostheses are obtained by CAD / CAM processing dental blocks. The inventors initially considered printing product identification information, such as a lot number, on the block portion of the dental block. However, in CAD / CAM processing, dental prostheses are obtained by cutting the block portion of the dental block. Therefore, if product identification information is printed on the block portion, the product identification information is also cut off when CAD / CAM processing begins. As a result, the product identification information cannot be confirmed during CAD / CAM processing or when the dental prosthesis is obtained after CAD / CAM processing is completed. After extensive research, the inventors discovered that the dental block disclosed herein can solve the above-mentioned problems, leading to the dental block disclosed herein. The dental block will be described below based on its specific configuration and with reference to the accompanying drawings.

[0013] FIG. 1 is a perspective view of a dental block 80 according to one embodiment of the present disclosure. In FIG. 1 , the dental block 80 includes a cylindrical pin portion 82 and a rectangular parallelepiped block portion 81. Furthermore, the pin portion 82 is provided approximately in the center of one of the faces of the rectangular parallelepiped block portion. That is, the dental block 80 includes the pin portion 82 and the block portion 81. The block portion 81 is a portion that will become the molded block portion through CAD / CAM processing. The shape of the block portion 81 is not particularly limited and may be, for example, a rectangular parallelepiped, cube, cylinder, or sphere. For example, when the shape of the block portion is a rectangular parallelepiped, the height X in FIG. 1 is preferably 10 mm to 20 mm, the vertical length Y is preferably 10 mm to 20 mm, and the horizontal length Z is preferably 15 mm to 65 mm. The method of using the molded block portion is not particularly limited. For example, the molded block portion can be used by removing a cavity in a patient's oral cavity to prepare an abutment tooth and then placing the block portion over the abutment tooth. Additionally, the molded block part can be used as a dental filling or bridge. Product identification information, a barcode, a QR code (registered trademark), a company logo, etc., as described below, may be printed on the block part.

[0014] The pin portion 82 is a portion used to attach the dental block to a CAD / CAM processing machine. The dental block 80 includes the pin portion 82, allowing the dental block to be fixed to the CAD / CAM processing machine and adjusted for positioning during processing. Furthermore, product identification information is printed on the pin portion. The pin portion is fixed to the CAD / CAM processing machine and is not actively removed during processing. Therefore, by printing the product identification information on the pin portion, the product identification information can be confirmed during CAD / CAM processing and after CAD / CAM processing is completed, when the dental prosthesis is obtained. As a result, the dental block has excellent product traceability. CAD / CAM processing is often performed semi-automatically using a processing machine, and the processing is long. Therefore, if a defect occurs during processing, it may be difficult to confirm the product identification information of the dental block, which is the raw material. The dental block of the present disclosure has the product identification information printed on the pin portion 82, making it easy to confirm the product identification information even in such cases. The idea of ​​printing product identification information on the pins was not present in the prior art. This is thought to be because, in conventional dental blocks that use thermosetting resin for the metal base, the laser is reflected off the non-flat metal base, narrowing the printable area and making the printing unclear.

[0015] FIG. 2 is a perspective view of a dental block 80 according to one embodiment of the present disclosure. In FIG. 2, the dental block 80 includes a pin portion and a rectangular parallelepiped block portion 81. The pin portion includes a cylindrical shank 82-1 and a cylindrical head 82-2. The shank 82-1 is located approximately at the center of the bottom surface of the cylindrical head 82-2. More specifically, when the pin portion is viewed from the longitudinal direction of the shank 82-1, the center of the bottom surface of the head 82-2 and the center of the bottom surface of the shank 82-1 overlap. Additionally, the head 82-2 is located approximately at the center of one of the faces of the rectangular parallelepiped block portion 81. More specifically, when the pin portion is viewed from the longitudinal direction of the shank 82-1, the center of the bottom surface of the head 82-2 and the center of one face of the block portion 81 overlap. A screw hole 83 is located approximately at the longitudinal center of the shank 82-1. In addition, product identification information (not shown) is printed on the head 82-2. That is, although the shape of the pin portion is not particularly limited, it is preferable that the pin portion has a shaft portion 82-1 and a head portion 82-2. In addition, it is preferable that the shaft portion 82-1 has a screw hole 83. By having the screw hole 83, it becomes easier to attach it to a CAD / CAM processing machine.

[0016] The shank 82-1 is the portion of the pin portion 82 that is attached to the CAD / CAM processing machine, and the head 82-2 is the portion of the pin portion 82 on which product identification information can be printed. That is, it is preferable that the product identification information be printed on the head 82-2. However, the product identification information may also be printed on the shank 82-1. That is, it is preferable that the product identification information be printed on at least one of the shank or the head. The shank 82-1 is the portion that is attached to the CAD / CAM processing machine, but it may be subjected to friction from the processing machine during processing. Therefore, if product identification information is printed on the shank 82-1, the product identification information may be erased. By having such a shank 82-1 and head 82-2, the printed product identification information is less likely to be erased even when the dental block is attached to the CAD / CAM processing machine. Note that in FIG. 1, the shank can also be said to constitute the pin portion 82.

[0017] FIG. 3 is a perspective view of one embodiment of the shaft portion 82-1. In FIG. 3, the shaft portion 82-1 has a constricted portion 84 located approximately in the center of the shaft portion 82-1 in the longitudinal direction. A screw hole 83 is provided approximately in the center of the shaft portion 82-1 in the longitudinal direction. However, the shape of the shaft portion 82-1 is not particularly limited, and may be, for example, a rectangular parallelepiped, a cube, or a cylinder. Of these, a cylindrical shape is preferable for the shaft portion 82-1. From the viewpoint of easier attachment to a CAD / CAM processing machine, it is more preferable that the shaft portion 82-1 has a constricted portion 84.

[0018] When the product identification information is printed on the shaft portion 82-1, the location of printing is not particularly limited, but it is preferable that the product identification information be printed on the side surface of the shaft portion 82-1. For example, if the shape of the shaft portion 82-1 is cylindrical, it is preferable that the product identification information be printed on the side surface of the cylinder. If the shaft portion 82-1 has a constricted portion 84, it is preferable that the product identification information be printed on a location of the shaft portion 82-1 other than the constricted portion 84. For example, when the product identification information is printed on the side surface of a cylinder, the printing area for printing the product identification information can be 5 to 100 area % of the total printable area of ​​the side surface of the cylinder, and preferably 10 to 90 area %. By setting the area within this range, the readability of the product identification information is likely to be improved.

[0019] The shape of the head 82-2 is not particularly limited and can be, for example, a rectangular parallelepiped, a cube, or a cylinder. Among these, a cylindrical shape is preferred for the head 82-2. A cylindrical shape for the head 82-2 is preferable because, compared to a rectangular parallelepiped or other shape, the side area is increased, thereby increasing the amount of product identification information that can be printed. Furthermore, when the head 82-2 is cylindrical and the shank 82-1 is cylindrical, it is preferred that, when the pin portion 82 is viewed from the longitudinal direction of the shank 82-1, the radius of the circle defining the outline of the head 82-2 is larger than the radius of the circle defining the outline of the shank 82-1. This makes it easier to increase the amount of product identification information that can be printed. Furthermore, when product identification information is printed on the head 82-2, the location of printing is not particularly limited. However, for example, when the head 82-2 is cylindrical, it is preferable that the product identification information be printed on the side of the cylinder. In this case, the printing area for the product identification information can be 5 to 100% of the total printable area of ​​the side surface of the cylinder, and preferably 10 to 90%. By setting the printing area in this range, the readability of the product identification information is likely to be improved.

[0020] Product identification information may be printed on the surface of the head 82-2 that contacts the stem 82-1. For example, if the head 82-2 is cylindrical, the product identification information may be printed on the surface portion of the head 82-2 surrounding the cylinder that contacts the stem 82-1. In this case, the printing area for printing the product identification information may be 5 to 100% of the total printable area of ​​the surface of the head 82-2 surrounding the cylinder that contacts the stem 82-1, and preferably 10 to 90%. By setting the area within this range, the readability of the product identification information is likely to be improved.

[0021] As described above, the prior art did not consider the idea of ​​printing product identification information on the pin portion 82. Furthermore, when printing product identification information, it is expected that it would be printed on the flat side surfaces that constitute the dental block. In contrast, according to the present disclosure, product identification information is printed on the pin portion 82 of the dental block 80, and further, even if the side surfaces of the shank 82-1 or head 82-2 that may constitute the pin portion 82 are non-flat (e.g., curved), the product identification information can be printed on the side surfaces. Furthermore, if the side surfaces of at least one of the shank 82-1 and head 82-2 are non-flat, printing the product identification information on the non-flat surface allows more product identification information to be imparted to the dental block.

[0022] The pin portion 82 and the block portion 81 are integrally molded. That is, it is preferable that the dental block 80 is an integrally molded product of the block portion 81 and the pin portion 82. Furthermore, when the pin portion 82 has a shaft portion 82-1 and a head portion 82-2, the shaft portion 82-1, the head portion 82-2, and the block portion 81 are integrally molded. That is, it is more preferable that the dental block is an integrally molded product of the block portion 81, the shaft portion 82-1, and the head portion 82-2. Integral molding improves productivity. The dental block material used for molding can be the one described below.

[0023] Although the product identification information is not particularly limited, it is preferable that the product identification information include one or more selected from the group consisting of the manufacturing date of the dental block, the manufacturing location of the dental block, the manufacturer of the dental block, the manufacturing lot number of the dental block, and the product name of the dental block. Including this information further improves product traceability. Additionally, a barcode, QR code (registered trademark), company logo, etc. may be printed on the pin portion. The height of the barcode and QR code (registered trademark) is preferably 0.2 to 2 mm, more preferably 0.2 to 1.8 mm. The width of the barcode and QR code (registered trademark) is preferably 1 to 2 mm, more preferably 1 to 1.8 mm. The height of the logo mark is preferably 0.02 to 2 mm, more preferably 0.02 to 1.8 mm. The width of the logo mark is preferably 0.02 to 2 mm, more preferably 1 to 1.8 mm.

[0024] The character height of the product identification information is not particularly limited, but from the viewpoint of further improving readability, it is preferably 0.1 mm to 2.0 mm, more preferably 0.6 to 1.0 mm. In particular, a height of 0.6 to 1.0 mm improves readability while making it easier to include more product identification information. The character width of the product identification information is not particularly limited, but from the viewpoint of further improving readability, it is preferably 0.1 mm to 2.0 mm, more preferably 0.6 to 1.0 mm. It is also more preferable that the character height and character width are within the above range. When the product identification information includes multiple characters, the character height of one or more of the multiple characters may be within the above range, or the character height of all of the characters may be within the above range. The character width of one or more of the multiple characters may be within the above range, or the character width of all of the characters may be within the above range. When the character height of all characters is within the above range, readability is more likely to be improved. When the character width of all characters is within the above range, readability is more likely to be improved. The font of the product identification information is not particularly limited, but for example, Arial can be used.

[0025] Materials that the dental block may contain are described below. The dental block contains a thermoplastic resin. In other words, the pin and block portions can be said to contain a thermoplastic resin. The thermoplastic resin is not particularly limited, and examples include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, polyamides, polystyrene, poly(meth)acrylic, polycarbonates, polyaryl ketones, polyphenylene ethers, and modified polyphenylene ethers. Among these, from the viewpoint of high strength and ease of integral molding, it is preferable to include one or more thermoplastic resins selected from the group consisting of polycarbonates, polyaryl ketones, and modified polyphenylene ethers. The polyaryl ketone is not particularly limited, and examples include polyether ketones, polyether ether ketones (PEEK), polyether ketone ketones (PEKK), and polyether ketone ether ketone ketones (PEKEKK). Among these, one or more selected from the group consisting of polyether ether ketones and polyether ketone ketones are preferred, with polyether ether ketones being more preferred. The thermoplastic resins may be used alone or in combination of two or more.

[0026] The content of the thermoplastic resin in the dental block is not particularly limited, but is preferably 70 to 95% by mass, more preferably 75 to 90% by mass, and even more preferably 75 to 85% by mass.

[0027] The dental block preferably contains an inorganic filler. The inorganic filler content in the dental block is not particularly limited, but is preferably 5 to 30% by mass. It is more preferably 10 to 25% by mass, and even more preferably 15 to 25% by mass. The inorganic filler content in the dental block material can be adjusted by changing the amount of inorganic filler added when producing the dental block material. The inorganic filler content can be measured by thermogravimetry (TG).

[0028] The inorganic filler is not particularly limited, but inorganic oxides such as silica, alumina, aluminosilicate glass, silica fiber, praseodymium oxide, erbium oxide, manganese oxide, titanium oxide, barium titanate, and yellow iron oxide are preferred. Sulfates such as calcium sulfate and barium sulfate are also preferred. Among these, one or more selected from the group consisting of titanium oxide, barium titanate, and barium sulfate are more preferred in terms of achieving a favorable color for the dental block. The inorganic filler may contain inorganic substances other than those listed above. Examples of inorganic substances other than those listed above include praseodymium salts such as praseodymium(III) chloride; erbium salts such as erbium chloride, erbium nitrate, erbium fluoride, and erbium oxalate; and manganese pink, a solid solution of manganese in aluminum oxide.

[0029] The dental block may contain known additives, such as antioxidants and ultraviolet absorbers.

[0030] The method for manufacturing the dental block is not particularly limited, but the dental block can be manufactured by molding a dental block material containing the above-mentioned thermoplastic resin and, if necessary, an inorganic filler, using a known molding method such as injection molding or extrusion molding. That is, the manufacturing method for the dental block preferably includes a step of molding the dental block material. It also preferably includes a molding step of integrally molding the pin portion and the block portion. By molding them integrally, it is no longer necessary to perform the subsequent printing process on the pin portion and the block portion as separate components.

[0031] The method for manufacturing a dental block preferably includes a printing step of printing product identification information on the pin portion. By including such a printing step, the product identification information is printed on the pin portion. The printing step is not particularly limited, and examples include a step of printing the product identification information on the pin portion by printing, and a step of printing the product identification information on the pin portion by laser marking. Among these, the printing step is preferably a printing step of printing the product identification information on the pin portion by laser marking. With such a printing step, the product identification information can be easily printed even when a resin with low printability, such as polyaryl ketone, is used as the thermoplastic resin. Furthermore, the printing step may be performed multiple times. By performing the printing step multiple times, it becomes easier to increase the printing area on which the product identification information is printed.

[0032] When the printing process is a process of printing product identification information on the pin portion by laser marking, the laser marking conditions such as scan speed, pulse frequency, and laser power can be adjusted appropriately depending on the content and density of the product identification information to be printed.

[0033] The configurations and combinations thereof in each embodiment are merely examples, and additions, omissions, substitutions, and other modifications of the configurations are possible as appropriate within the scope of the spirit of the present invention. The present disclosure is not limited to the embodiments, but is limited only by the scope of the claims.

[0034] The present disclosure will be specifically described below with reference to examples, but the present disclosure is not limited to the aspects of the following examples.

[0035] Example 1: 100 parts by mass of polyether ether ketone (VESTAKEEP (registered trademark) L4000G manufactured by EVONIK) was pulverized to an average particle size d50 of 10 μm to obtain a PEEK pulverized material. Subsequently, 20 parts by mass of titanium oxide as an inorganic filler was mixed with the PEEK pulverized material using a twin-screw kneader to obtain a dental block material. The obtained dental block material was injection-molded by thermal melting to obtain a dental block having a rectangular parallelepiped block portion and a pin portion having a shaft portion and a head portion, the head portion of which was cylindrical. Subsequently, the pin portion of the dental block was laser-marked using a 3-Axis Hybrid Laser Marker MD-X2000 manufactured by Keyence. The laser marking method was specifically as follows. The laser processing conditions were set using Marking Builder Plus Ver. 2 manufactured by Keyence. The product identification information was set to the font Arial with a character height of 0.6 mm, and the printing surface shape layout was set to a 12 mm cylinder. Laser marking was performed with a laser power of 50%, a scan speed of 1000 mm / s, a pulse frequency of 10 kHz, and one printing. A photograph of the resulting dental block is shown in Figure 4.

[0036] Example 2 A dental block was obtained in the same manner as in Example 1, except that the block, head, and stem were printed with a company logo, the block had a figure height of 2.4 mm and a flat print surface layout, the head had a figure height of 1.8 mm and a cylindrical print surface layout with a diameter of 12 mm, and the stem had a figure height of 1.6 mm and a cylindrical print surface layout with a diameter of 5 mm. A photograph of the resulting dental block is shown in Figure 5.

[0037] [Examples 3 and 4] Dental blocks were obtained in the same manner as in Example 1, except that printing was performed on the block portion and the head portion, and the character heights on the block portion and the head portion were set to 1.0 mm and 0.6 mm, respectively, from the left in Figure 6. A photograph of the obtained dental blocks is shown in Figure 6. From Figure 6, it can be seen that in Examples 3 and 4, more printing was possible on the head portion than on the block portion.

[0038] Reference Example 1 Dental blocks were obtained in the same manner as in Example 1, except that the block portion was printed with character heights of 1.0 mm, 0.6 mm, and 0.3 mm. The printed content was "Height 1.0 mm," "Height 0.6 mm," and "Height 0.3 mm" from right to left in Figure 7. A photograph of the obtained dental block is shown in Figure 7. Reference Example 1 shown in Figure 7 showed significantly better readability at heights of 0.6 mm or more.

[0039] Comparative Example 1 A dental block was obtained in the same manner as in Example 1, except that printing was performed only on the block portion. A photograph of the obtained dental block is shown in FIG.

[0040] According to the present disclosure, a dental block with excellent product traceability can be provided.

[0041] 80 Dental block, 81 Block portion, 82 Pin portion, 82-1 Shank portion, 82-2 Head portion, 83 Screw hole, 84 Neck portion

Claims

1. A dental block comprising a pin portion and a block portion, wherein the dental block contains a thermoplastic resin, the pin portion and the block portion are integrally formed, and product identification information is printed on the pin portion.

2. The dental block according to claim 1, wherein the pin portion has a shaft portion and a head portion, and the product identification information is printed on at least one of the shaft portion and the head portion.

3. The dental block according to claim 2, wherein the product identification information is printed on a side surface of the shaft portion.

4. The dental block according to claim 2 or 3, wherein the head portion has a cylindrical shape, and the product identification information is printed on a side surface of the head portion.

5. The product identification information includes one or more selected from the group consisting of the manufacturing date of the dental block, the manufacturing location of the dental block, the manufacturer of the dental block, the manufacturing lot number of the dental block, and the product name of the dental block. The dental block according to any one of claims 1 to 4.

6. The dental block according to any one of claims 1 to 5, further containing an inorganic filler, and the content ratio of the inorganic filler in the dental block is 5 to 30% by mass.

7. The dental block according to any one of claims 1 to 6, wherein the thermoplastic resin includes one or more thermoplastic resins selected from the group consisting of polyetheretherketone, polyetherketoneketone, polycarbonate, and modified polyphenylene ether.

8. A method for manufacturing a dental block according to any one of claims 1 to 7, comprising a molding step of integrally molding the pin portion and the block portion, and a printing step of printing the product identification information on the pin portion by laser marking.

Images