Dental blank and method for recovering scraps from dental blanks

Abstract

Provided are a dental blank and a method for recovering scrap material of a dental blank described below, the dental blank and the method enabling efficient and smooth recovery of dental blank scrap material generated through machining, and regeneration through horizontal recycling.　This dental blank comprises an information tag attached thereto that includes at least specific information associated with material information, the specific information being information that has been agreed upon between a manufacturer of dental blank raw material and a manufacturer of the dental blank. The information tag is an information medium from which the specific information is read when scrap material of the dental blank is recovered. This method for recovering scrap material from a dental blank comprises: a recovery step for recovering scrap material, generated through machining of a dental blank, from a machining operator; and a selection step for selecting specific scrap material for which specific information, associated with material information of the dental blank and agreed upon between a manufacturer of the dental blank raw material and a manufacturer of the dental blank, can be read from the information tag attached to the scrap material.

Description

Dental blanks and method for recovering dental blank scraps

[0001] The present disclosure relates to a dental blank, and more particularly to a dental blank made of a calcined ceramic body, and further to a dental blank made of a calcined ceramic body that allows for smooth recovery and recycling of scrap material generated after cutting.

[0002] Sintered bodies (ceramic materials) such as alumina and zirconia, which have excellent biocompatibility, are widely used as dental materials. Among ceramics, zirconia sintered bodies combine aesthetics close to natural teeth with high mechanical strength, making them widely used in dental prostheses such as crowns, bridges, inlays, onlays, and abutments.

[0003] In a method for producing a dental prosthesis made of a sintered body, a raw material powder is first molded into a green compact (a green compact), which is then calcined to produce a calcined body (a dental blank). The calcined body is then machined in a dental laboratory or the like to give it the shape of the dental prosthesis, taking into account thermal shrinkage due to sintering. The calcined body is then sintered to produce a sintered body (a dental prosthesis), which is then finely adjusted and finally fitted to the patient.

[0004] Meanwhile, there is an increasing demand for recycling ceramic materials from the viewpoint of reducing industrial waste, reducing environmental impact, etc. Known methods for recycling ceramic materials include a technology for recycling electrolyte sheets for fuel cells made of sintered zirconia (Patent Document 1) and a technology for recycling grinding balls made of sintered zirconia (Patent Document 2).

[0005] JP2010-027358A JP10-218662A

[0006] Since dental blanks and other calcined bodies are not subjected to a sintering process, they are considered suitable for recycling (particularly horizontal recycling and closed-loop recycling). However, both Patent Documents 1 and 2 relate to recycling technologies for sintered bodies, and are not recycling technologies for dental blanks, particularly dental blank scraps generated after cutting.

[0007] In addition, multiple types of dental blanks are used depending on the characteristics of the desired dental prosthesis. Dental blank scraps generated after cutting are a mixture of different compositions and types, making recovery with the intention of recycling difficult. Therefore, currently, the only possibilities are for them to be disposed of by processing companies such as dental laboratories, or for cascade recycling, such as converting them into cement raw materials. Even if dental blank scraps could be recovered, horizontal recycling requires that each recovered scrap be separated after undergoing compositional analysis. For this reason, horizontal recycling of dental blank scraps has been practically impossible.

[0008] The present disclosure aims to provide a dental blank that allows for efficient and smooth recovery of dental blank scraps generated by cutting and regeneration processing through horizontal recycling.

[0009] That is, the present invention is as described in the claims, and the gist of the present disclosure is as follows. [1] A dental blank having an information tag attached thereto containing at least specific information linked to material information, the specific information being information agreed upon between the manufacturer of the dental blank raw material and the manufacturer of the dental blank, and the information tag being an information medium from which the specific information is read when scrap material of the dental blank is collected. [2] The dental blank described in [1] above, wherein the specific information includes one or more selected from the group consisting of the raw material ratio, composition, average composition, contained elements, color tone, color tone code, average color tone, and average color tone code of the dental blank. [3] The dental blank described in [1] or [2] above, wherein the specific information includes one or more selected from the group consisting of the manufacturing lot, manufacturing location, manufacturing year, and collection deadline of the dental blank. [4] The dental blank described in any one of [1] to [3] above, wherein the specific information includes at least one of the model number and the name of the manufacturer of the dental blank. [5] The dental blank according to any one of [1] to [4] above, wherein two or more information tags are attached to the dental blank. [6] The dental blank according to any one of [1] to [5] above, wherein the information tag is attached to a non-cutting portion of the dental blank. [7] The dental blank according to any one of [1] to [6] above, wherein the dental blank has a disk shape and the information tag is attached to the circumferential side surface of the disk. [8] The dental blank according to any one of [1] to [6] above, wherein the dental blank has a columnar shape and the information tag is attached to the bottom side of the block. [9] The dental blank according to any one of [1] to [8] above, wherein the dental blank is a calcined ceramic body.

[10] The dental blank according to any one of [1] to [9] above, wherein the dental blank is a calcined zirconia body.

[11] A dental blank scrap recovery method comprising: a recovery step of recovering scraps generated by cutting the dental blank described in any one of [1] to

[10] above from a processing business operator; and a selection step of selecting specific scraps from which specific information linked to material information of the dental blank agreed upon between the dental blank raw material manufacturer and the dental blank manufacturer can be read from the information tag attached to the scraps.

[12] The dental blank scrap recovery method described in

[11] above, including a supply step of supplying dental blank raw materials to the blank manufacturer prior to the recovery step.

[13] The dental blank scrap recovery method described in

[12] above, including a specific information arrangement step of arranging the specific information prior to the supply step.

[14] The dental blank scrap recovery method described in any one of

[11] to

[13] above, including a recycling step of recycling the specific scraps based on the specific information after the selection step.

[0010] The present disclosure provides a dental blank that allows for efficient and smooth recovery of dental blank scraps generated by cutting and regeneration processing through horizontal recycling.

[0011] 1 is a diagram illustrating a dental blank 10 according to an embodiment of the present disclosure; FIG. 2 is a cross-sectional view showing layers (shades) of the dental blank 10; FIG. 3 is a diagram illustrating a dental block 20; FIG. 4 is a diagram illustrating an information tag 12; FIG. 5 is a diagram illustrating an offcut 15 of the dental blank 10; and FIG. 6 is a flowchart illustrating an offcut recovery method according to an embodiment of the present disclosure.

[0012] The dental blank of the present disclosure will be described below by showing an example of an embodiment thereof. Note that the various configurations disclosed in the following description can be combined in any desired manner, and the upper, lower, and ranges of the numerical values ​​disclosed in this specification can also be combined in any desired manner. [Dental Blank] The dental blank of this embodiment will be described below by taking an example in which the dental blank is a dental blank made of a calcined ceramic body (ceramic blank) and a dental blank made of a calcined zirconia body (zirconia blank).

[0013] Fig. 1 shows a dental blank according to the present embodiment, specifically a disc-shaped dental blank (hereinafter also referred to as a "dental disc"). Fig. 2 shows a cross-sectional view of a dental blank 10 made up of multiple layers. In Fig. 2, the dental blank is a dental disc having a laminated structure of two or more layers (e.g., 2 to 15 layers, further 2 to 10 layers, or even 3 to 8 layers) with different compositions, and the dental blank 10 is a dental disc having a layer structure in which at least one of the color tone and the translucency is graded along the thickness direction.

[0014] 3 is a diagram showing a cylindrical dental blank (dental block) 20. As described above, the dental blank 10 may have any shape that can be machined using CAD / CAM, such as a disk, column, plate, or column.

[0015] The dental blank 10 is not limited to having a pair of peripheral grooves 11. The information tag 12 is not limited to being attached to the side peripheral surface 10s. The information tag 12 may be attached to another non-cut portion (a portion that remains as waste material 15).

[0016] When the dental blank 10 is a dental disc, the size is arbitrary, but examples include a diameter of 10 mm or more and 100 mm or less and a thickness of 3 mm or more and 30 mm or less, preferably a diameter of 80 mm or more and 110 mm or less and a thickness of 12 mm or more and 20 mm or less, and more preferably a diameter of 98 mm and a thickness of 16 mm.

[0017] To facilitate fixation to a CAD / CAM device, the dental blank 10 preferably has a gripping portion (clamping portion) on the peripheral side surface 10s that is gripped by the CAD / CAM device during cutting. In this case, the dental blank 10 preferably has a pair of peripheral grooves 11 on the peripheral edge 10e. The pair of peripheral grooves 11 can be used to grip the dental blank 10 to the CAD / CAM device. Since the peripheral side surface 10s is sandwiched between the pair of peripheral grooves 11, it becomes a non-cutting area. However, the dental blank does not need to have peripheral grooves 11 as long as it has a structure that allows it to be fixed to a CAD / CAM device during cutting.

[0018] The dental blank 10 is a zirconia blank, which is a dental blank containing zirconia as the main component and a stabilizing element and a coloring element as secondary components.

[0019] The dental blank 10 may have a single-layer structure, i.e., a uniform composition throughout the entire dental blank. On the other hand, dental prostheses are required to aesthetically harmonize with the surrounding tooth structure (the patient's natural teeth). Therefore, the dental blank 10 may have two or more layers 13 along its thickness. In this case, each layer 13 is not limited to being clearly separated, but may include two or more regions (e.g., 2 to 15 regions, or even 2 to 10 regions, or even 3 to 8 regions). Two or more layers 13 may be stacked to form a gradation. The gradation may be formed by at least one of color tone and translucency. A clear interface between the regions may exist, but this is not required. When the dental blank has a structure consisting of two or more layers, the coloring element may be contained in at least one layer.

[0020] The dental blank 10 is a calcined body obtained by calcining a green body obtained by molding a raw material for the dental blank. The dental blank 10 is manufactured by a dental blank manufacturer (a disc manufacturer; hereinafter, also referred to as a "blank manufacturer"). The raw material for the dental blank is zirconia (ZrO ２The present invention relates to a powder of zirconia (zirconium dioxide) containing metal elements such as a stabilizing element and a coloring element. Examples of the stabilizing element include one or more elements selected from the group consisting of yttrium (Y), calcium (Ca), and magnesium (Mg), and further includes yttrium. Examples of the coloring element include one or more elements selected from the group consisting of titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), manganese (Mn), praseodymium (Pr), neodymium (Nd), europium (Eu), gadolinium (Gd), terbium (Tb), erbium (Er), and ytterbium (Yb). Examples of other metal elements include one or more elements selected from the group consisting of aluminum (Al), silicon (Si), and germanium (Ge). The zirconia powder referred to here is a powder containing zirconia as the main component (i.e., a so-called zirconia powder) and is not limited to a powder consisting solely of zirconia. The dental blank raw material is produced by a dental blank raw material manufacturer (hereinafter simply referred to as the "raw material manufacturer") and provided to the blank manufacturer. The blank manufacturer produces a dental blank 10 having a predetermined composition (raw material ratio) by molding and calcining the raw material (powder) provided by the raw material manufacturer in accordance with the aesthetics of the intended dental prosthesis. If necessary, multiple raw materials may be mixed to form a mixed powder, which is then molded and calcined. Furthermore, prior to calcination, the green body may be mixed with a solution containing a coloring element.

[0021] The dental blank 10 is a precursor to a dental prosthesis, and is subjected to cutting processing using a CAD / CAM device (not shown) at a processing business such as a dental laboratory (dental technician). Through cutting, the dental blank 10 is cut into the shape of a dental prosthesis such as a crown. The shape after cutting takes into account thermal shrinkage during sintering, and therefore is larger than the shape of the dental prosthesis to be fitted to the patient.

[0022] The dental blank 10 is affixed with an information tag (described below) that includes at least identifying information linked to the material information. The "identifying information" is information that can be linked to the material information, and the "material information" is information that allows identification of the dental blank 10, and preferably includes at least composition information, and more preferably includes one or more selected from the group consisting of composition information, product information, and manufacturing information (all of which are described below). By attaching identifying information to the dental blank 10, selection and collection can be carried out efficiently.

[0023] The specific information preferably includes one or more items selected from the group consisting of raw material ratio, composition (chemical composition), average composition, contained elements, color tone, color tone code, average color tone, and average color tone code (hereinafter also referred to as "composition information"). The composition information allows the identity of the dental blank 10 to be directly confirmed. The specific information preferably includes one or more items selected from the group consisting of raw material ratio, composition, contained elements, color tone, and color tone code, and preferably includes at least one of a composition and a color tone code. Furthermore, when the dental blank 10 has a structure consisting of two or more layers, the composition information preferably includes, in addition to or instead of the composition, color tone, and color tone code, one or more items selected from the group consisting of an average composition, average color tone, and average color tone code, or one or more items selected from the group consisting of a representative composition, representative color tone, and representative color tone code, which enable linking to the most abundant component, etc. The "raw material ratio" is information about the type (e.g., powder product name) and amount of each raw material used in manufacturing the dental blank 10, and the "color tone" is the target color tone of the dental prosthesis obtained by sintering the dental blank 10, for example, L ＊ a ＊ b ＊ Lightness L indicated by the color system ＊ , hue a ＊ and b ＊ The "color code" is a code that represents each color tone in the dental color sample, and is, for example, a code indicated by any of the alphabets A1 to D4 in the Vita Classical Shade, and a number.

[0024] If the composition information cannot be obtained, the raw material manufacturer will need to perform a component analysis for each scrap 15. The component analysis will require taking a portion of each scrap 15, dissolving it, and performing an instrumental component analysis of the resulting sample solution, or an instrumental component analysis using electron beams or X-rays. In this case, not only will performing a component analysis for all scraps require a huge amount of work, but if unexpected elements are contained, identifying the components will require even more time and effort. Therefore, even if such scraps can be recovered, they will be virtually impossible to regenerate through horizontal recycling.

[0025] The specific information preferably includes at least one of the dental blank's model number and the manufacturer's name (hereinafter also referred to as "product information"), and preferably includes at least the manufacturer's name. The "model number" is the product name of the dental blank as determined by the blank manufacturer. By including product information in the specific information, rough sorting becomes possible after collection. In other words, scrap materials collected from dental laboratories, etc., may contain a mixture of products from different block manufacturers. In this case, sorting by manufacturer or by manufacturer and product becomes possible, making it easier to efficiently sort for horizontal recycling.

[0026] The specific information preferably includes one or more selected from the group consisting of the dental blank's production lot, production location, production year, and collection deadline (hereinafter also referred to as "production information"); more preferably, it includes at least one of the production year and collection deadline, and even more preferably, it includes the collection deadline. By including the production information, not only recycling but also traceability becomes possible. As described below, the specific information is agreed upon in advance between the raw material manufacturer and the blank manufacturer. Therefore, by attaching a collection deadline agreed upon between the two parties, it becomes possible to trace not only the dental blank but also the raw materials used. Note that the "production year" is information that can identify the time of production, and instead of the production year, the production month or production date may be used.

[0027] The specific information linked to the material information is information that is used when collecting and regenerating (recycling) the waste material 15 of the dental blank 10. In other words, the specific information linked to the material information includes information that is necessary and important for recycling the waste material 15.

[0028] Processing businesses such as dental laboratories cut and process a variety of different dental blanks. As a result, the scrap 15 generated varies widely in terms of manufacturer, composition, contained elements, color, etc. If specific information linked to the material information of the scrap 15 (and dental blank 10) cannot be identified, the recycling process of the scrap 15 (dental blank) by entities other than the raw material manufacturer or blank manufacturer becomes extremely complicated, making horizontal recycling extremely difficult.

[0029] [Information Tag] FIG. 4 is a diagram showing the information tag 12. The information tag 12 is an information medium from which specific information can be read when the dental blank 10 scrap 15 is collected. The information tag 12 is attached to the side surface 10s of the dental blank 10. The information tag 12 may be any information medium capable of capturing specific information linked to material information, and is preferably a machine-readable information medium, such as a code symbol. The information tag 12 may also include one or more characters selected from the group consisting of letters, numbers, and symbols. The type, size, and display format of the code symbol may be appropriately selected depending on the amount of information to be added to the information tag 12 and the shape of the dental blank 10. For example, the code symbol may be at least one of a one-dimensional and two-dimensional code symbol, specifically at least one of a barcode and a QR code (registered trademark). The information tag 12 may also include a unique code. Preferably, the code symbol allows information to be read even if a portion of it is missing.

[0030] The information tag 12 is preferably composed of at least one of printing and engraving, and may be attached by at least one of printing and textured processing, and is preferably composed of a material that can be removed by a recycling process, such as ink printing, for example, an organic component, or a means that can be removed by a recycling process.

[0031] One or more information tags 12 may be attached to the dental blank 10, but two or more are preferred. This makes it easier to ascertain the specific information of each divided piece from the remaining information tags 12, even if some tags are missing or if the scrap material 15 is damaged and separated (divided) into multiple pieces. The number of information tags 12 attached to the dental blank 10 may be 2 to 50 or 2 to 10. The multiple information tags 12 may all have the same code symbol, or a barcode and a QR code may be used in combination, or two or more different code symbols may be used in combination.

[0032] The information tag 12 is preferably attached to a non-cut portion of the dental blank. This reduces the risk of damage to the information tag 12 due to the cutting process. The non-cut portion is the portion of the dental blank 10 that remains after the cutting process, such as the side surface 10s in the case of a dental disc, or the bottom side of the block body in the case of a dental block 20. Therefore, in the dental disc, the information tags 12 are preferably arranged at least on the side surface 10s, more preferably on the side surface 10s, and even more preferably at equal intervals on the side surface 10s. For example, when there are two information tags 12 attached to the side surface 10s, they are arranged at 180° intervals, when there are three information tags 12 attached, they are arranged at 120° intervals, and when there are four information tags 12 attached, they are arranged at 90° intervals. The information tags 12 only need to be attached to at least the non-cut portion, and may be attached to the main surface 10a of the dental blank 10, or to at least one of the side surface 10s and the main surface 10a. When the information tag 12 is attached to the main surface 10a, it is preferable that the information tag 12 is placed in a portion that will remain after multiple cutting processes, such as at least one of the outer periphery and the center of the main surface 10a.

[0033] [Scrap 15] Figure 5 is a diagram showing scrap 15 of dental blank 10. A dental prosthesis shape (not shown) that takes thermal shrinkage into consideration is cut from dental blank 10 by cutting using a CAD / CAM device. Therefore, the portion of the dental blank left in the CAD / CAM device after cutting corresponds to scrap 15. In other words, scrap 15 is at least one of the dental blank having one or more holes (perforations) in the shape of the dental prosthesis and its divided pieces.

[0034] [Scrap Recycling Method] Figure 6 is a flowchart showing the scrap recycling method. In this embodiment, the dental blank scrap recycling method includes a collection step S30 in which scraps 15 resulting from the cutting of dental blanks 10, each of which is attached with an information tag 12 containing at least specific information linked to material information, are collected from a processing company, and a selection step S40 in which specific scraps 15K are selected from the information tag 12 attached to the scraps 15, from which specific information linked to the material information of the dental blank 10 agreed upon between the dental blank raw material manufacturer and the dental blank manufacturer can be read. Furthermore, the collection step S30 may be preceded by a supply step S20 in which the dental blank raw material is supplied to the blank manufacturer. Furthermore, the supply step S20 may be preceded by a specific information agreement step S10 in which the raw material manufacturer and the blank manufacturer agree on specific information linked to the dental blank's composition information. Furthermore, after the selection step S40, the method may include a recycling step S50 in which the specific scraps 15K are recycled based on the specific information.

[0035] The specific information arrangement step S10 is a step in which the raw material manufacturer and the blank manufacturer arrange specific information linked to the composition information of the dental blank, and in this step, arrangements are made regarding the content of the specific information linked to the material information of the dental blank 10, rules for assigning the specific information, the format of the information tag 12, and other specific information required for selecting and collecting scrap material 15. Because the specific information may include confidential information related to the blank manufacturer's product lineup and other manufacturing information of the blank manufacturer, it is preferable that the specific information be managed as mutual business confidential information between the raw material manufacturer and the blank manufacturer, and it is preferable that it be managed and protected as non-public information.

[0036] The supplying step S20 is a step of supplying raw materials for dental blanks to a blank manufacturer, and includes a raw material supplying step S21, a dental blank manufacturing step S22, a tagging step S23, and a providing step S24.

[0037] In the raw material supply step S21, a raw material manufacturer supplies raw materials for the dental blank to the blank manufacturer. The raw material manufacturer supplies one or more raw materials, preferably zirconia powder, to the blank manufacturer. The powder preferably contains zirconia as a primary component and a stabilizing element and a coloring element as secondary components.

[0038] In the dental blank manufacturing step S22, the blank manufacturer manufactures the desired dental blank using the raw material (zirconia powder) supplied by the raw material manufacturer. When manufacturing the dental blank, the blank manufacturer may mix two or more raw materials, or may use a coloring component other than powder, such as a coloring solution, if necessary.

[0039] In the tagging step S23, the blank manufacturer attaches an information tag 12 containing specific information to the dental blank 10, etc. The information tag 12 is attached to the dental blank 10, etc. by means of at least one of printing and engraving. The information tag 12 can be attached to the dental blank 10 in accordance with the content specified in the specific information arrangement step S10, such as the format, number, and location of the information tag 12.

[0040] The providing step S24 is a step in which the blank manufacturer provides the dental blank 10 or the like having the information tag 12 to a dental laboratory or other processing business operator that performs cutting processing.

[0041] The recovery process S30 is a process of recovering scrap material 15 generated by cutting processing of dental blanks 10 that are attached with information tags 12 that contain at least specific information linked to material information from processing companies, and includes cutting processing S31 and a scrap material recovery process S32.

[0042] The cutting process S31 is a process of cutting the dental blank 10. A processing business such as a dental laboratory uses a processing device such as a CAD / CAM device to cut the dental blank 10 into the shape of the dental prosthesis based on information provided by the dentist. This process generates a precursor of the dental prosthesis and scrap material 15.

[0043] In the scrap collection step S32, scrap materials 15 are collected from processing businesses such as dental laboratories. The collection of scrap materials 15 may be carried out so that the scrap materials 15 are ultimately delivered to a business that regenerates (recycles) the scrap materials 15. The scrap materials 15 may be collected by at least one of the blank manufacturer and the raw material manufacturer, or the scrap materials 15 collected by the blank manufacturer may be further collected by the raw material manufacturer. Furthermore, scrap materials 15 may be collected by a collection business that performs primary collection from processing businesses, such as a collection business designated by at least one of the blank manufacturer and the raw material manufacturer. Therefore, collection in the collection step S30 may be carried out directly by the processing business, or may be carried out via a collection business that performs primary collection from the processing business instead of or in addition to the processing business.

[0044] On the other hand, the processing company may collect the scrap material 15 by sending it to at least one of the blank manufacturer and the raw material manufacturer.

[0045] The scrap 15 is a calcined body having perforations, and is therefore very fragile and easily broken, so that the scrap 15 may be damaged (broken) and divided into two or more pieces (scrap pieces, broken fragments) during transportation in the scrap collection step S32.

[0046] The selection process S40 is a process of selecting specific scrap 15K from the information tag 12 attached to the scrap 15, from which specific information linked to the material information of the dental blank 10 agreed upon between the dental blank raw material manufacturer and the dental blank manufacturer can be read, and includes a tag reading process S41 and a scrap selection process S42.

[0047] In the tag reading step S41, the information tags 12 of all the collected scraps 15 are read. If the scraps 15 are divided pieces, the information tags 12 of the divided pieces to which the information tags 12 are attached may be read.

[0048] The information tag 12 may be read by any means capable of grasping the specific information, for example, by a code symbol reading means, specifically, at least one of a barcode reader and image analysis.

[0049] In the scrap selection step S42, scraps 15K (hereinafter also referred to as "specific scraps") from which specific information can be read from the information tag 12 are selected and sorted. The specific scraps 15K have clear attributes such as material composition, so they can be collected and suitably used for horizontal recycling.

[0050] The specific scraps 15K may be selected and separated based on their attributes, and it is particularly preferable to select and separate them based on at least one of the elements contained therein and the composition, which makes it easier to apply them to regeneration (recycling).

[0051] On the other hand, the material information of scraps 15 and their divisions cannot be determined if the specific information cannot be read due to a missing or lost information tag 12. Although it is possible to select and separate such scraps after obtaining composition information separately through instrumental analysis, etc., from the viewpoint of disposal efficiency, they may also be treated as targets for cascade recycling or disposal.

[0052] The recycling step S50 is a step of recycling the specific scrap materials 15K based on the specific information, and the specific scrap materials 15K can be recycled based on the specific information. Because the specific scrap materials 15K have clear attributes such as material composition, it is possible to set recycling conditions appropriate for each group of selected specific scrap materials 15K based on the specific information.

[0053] An example of a regeneration method in the regeneration step S50 is a regeneration method (hereinafter also referred to as a "grinding and regeneration method") in which the specific scrap 15K is pulverized to obtain a powder (recycled powder). If necessary, the regeneration step S50 may include at least one of the following steps (none of which are shown): a step of washing at least one of the specific scrap 15K and its pulverized material to remove impurities prior to pulverization; a particle size adjustment step of adjusting the particle size of the pulverized specific scrap 15K after pulverization; and a step of drying at least one of the specific scrap 15K and its pulverized material (none of which are shown).

[0054] The powder obtained by the regrind method (recycled powder) can be used as a raw material for calcined bodies and sintered bodies. The recycled powder has a composition derived from the dental blank 10. Therefore, the recycled powder is particularly suitable as a raw material for dental blanks (recycled dental blanks).

[0055] The regeneration method in the regeneration step S50 may also be a regeneration method (hereinafter also referred to as the "dissolution regeneration method") in which the specific mill scraps 15K are dissolved to obtain a solution (recycled solution). Dissolution can be performed by contacting the specific mill scraps 15K with a solution that dissolves the specific mill scraps 15K, such as an acid. Prior to dissolution, the specific mill scraps 15K may be crushed, washed, and dried. The solution (recycled solution) obtained by the dissolution regeneration method can be used as a raw material solution for powder synthesis, preferably for zirconia powder synthesis, or as a raw material for one or more powder production methods selected from the group consisting of neutralization coprecipitation, hydrolysis, and hydrothermal treatment. The raw material obtained thereby is further suitable as a raw material for dental blanks.

[0056] Furthermore, the recycled solution may be purified by ion exchange or the like to remove the elements contained therein, and may be used for desired purposes as a solution of various metal ions including zirconium.

[0057] In this way, according to the dental blank of this embodiment, the waste material 15 of the dental blank 10 can be efficiently recovered so that it can be horizontally recycled as a material for dental blanks.

[0058] The above describes a preferred embodiment of the present disclosure using a zirconia block as an example, but the dental blank in the present disclosure may be any calcined ceramic body, and can also be applied to dental blanks made of calcined metal oxides such as alumina.

[0059] The entire contents of the specifications, claims, drawings and abstracts of Japanese Patent Application No. 2023-201431 filed on November 29, 2023 and Japanese Patent Application No. 2023-201448 filed on November 29, 2023 are hereby incorporated by reference as the disclosure of the specification of the present disclosure.

[0060] 10 Dental disc (dental blank) 10e Periphery 10s Side peripheral surface (non-cutting portion) 11 Peripheral groove 12 Tag (code symbol) 15 Scrap material 15K Specific scrap material 20 Dental block (dental blank)

Claims

1. A dental blank having an information tag attached thereto that includes at least specific information linked to material information, said specific information being information agreed upon between a manufacturer of dental blank raw materials and a manufacturer of dental blanks, and said information tag being an information medium from which said specific information can be read when scraps of said dental blank are collected.

2. The dental blank of claim 1, wherein the specific information includes one or more selected from the group consisting of the raw material ratio, composition, average composition, contained elements, color tone, color tone code, average color tone, and average color tone code of the dental blank.

3. The dental blank of claim 1 or 2, wherein the identifying information includes one or more selected from the group consisting of manufacturing lot, manufacturing place, manufacturing year, and recall date of the dental blank.

4. The dental blank of claim 1 or 2, wherein the identifying information includes at least one of a model number and a name of a manufacturer of the dental blank.

5. The dental blank of claim 1 or 2, wherein two or more of said information tags are affixed to said dental blank.

6. The dental blank of claim 1 or 2, wherein said information tag is affixed to a non-cut portion of said dental blank.

7. A dental blank according to claim 1 or 2, wherein said dental blank has a disk shape and said information tag is attached to a peripheral side surface of said disk.

8. The dental blank according to claim 1 or 2, wherein the dental blank has a columnar shape and the information tag is attached to the bottom side of the block body.

9. A dental blank according to claim 1 or 2, wherein the dental blank is a calcined ceramic body.

10. A dental blank according to claim 1 or 2, wherein the dental blank is a calcined body of zirconia.

11. A method for recovering dental blank scraps, comprising: a recovery step of recovering scraps generated by the cutting processing of the dental blank described in claim 1 from a processing company; and a selection step of selecting specific scraps from which specific information linked to material information of the dental blank agreed upon between a raw material manufacturer of the dental blank and a dental blank manufacturer can be read from the information tag attached to the scraps.

12. A method for recovering dental blank scraps according to claim 11, further comprising a supplying step of supplying raw materials for dental blanks to the blank manufacturer prior to the recovering step.

13. The dental blank scrap recovery method according to claim 12, further comprising a specific information determination step of determining the specific information prior to the supply step.

14. A dental blank scrap recovery method as described in claim 11 or 12, further comprising a recycling step of recycling the specific scrap based on the specific information after the selection step.

Images