Abstract: Provided is a dental blank. The dental blank includes: a seating portion provided in an artificial tooth processing apparatus; and a material portion configured to be inserted into the seating portion, wherein the material portion includes a plurality of outer contacting portions in contact with an inner side of the seating portion, and may have a polygonal shape in a cross-section.

Abstract: Proposed is a hybrid ceramic prosthesis. Since the prosthesis is made of a novel hybrid ceramic material, the prothesis has a similar color and transmittance to natural teeth, minimizes tooth removal during preparation for placement of the prothesis, is securely attached to the target tooth by snap-fit fastening to prevent detachment of the prothesis and re-treatment caused by the prothesis detachment, and can be more conveniently applied to the patient than conventional prostheses, enabling an one-day-one-stop dental procedure, thereby reducing burden to patients. The prothesis is useful as a primary crown.

Abstract: The present invention relates to a method for manufacturing a prefabricated crown by processing and tabulating the type, size, material and color of prefabricated crowns for sub-gingival and supra-gingival, and actual and try-in crowns by a table system (1), and a prefabricated crown manufactured therefrom, and the method includes a first step (S100) of classifying a plurality of prefabricated crowns by type and size by a first module (5) of the table system (1); a second step (S110) of classifying the plurality of prefabricated crowns by color and material by a second module (7) of the table system (1); a third step (S120) of tabulating the type, size, color and material data of the prefabricated crowns classified in the first and second steps (S100, S110) by a third module (9) of the table system (1), and assigning an identification code to each data; a fourth step (S130) of manufacturing the tabulated plurality of prefabricated crowns; and a fifth step (S140) of inputting the measured type, size, color and

Abstract: An inverted nanocone structure of the present disclosure includes a first surface, a second surface spaced apart from the first surface by a predetermined distance and having a greater area than the first surface, and a body having an inverted cone shape between the first surface and the second surface, wherein at least one activated point defect center is provided in the body.

Abstract: Dental composite composition including a glass ceramic and a curable organic material is described in which the glass ceramic includes a crystal phase having an average grain size of 50 to 400 nm, and the dental composite composition is provided as a dental prosthetic material exhibiting superior transparency and mechanical properties comparing to conventional composite products containing micro-sized crystal grains and also has excellent aesthetics and processability required for prosthetic materials for same-day dental prosthetic service.

Abstract: Provided is a dental bulk block made from a glass-ceramic material having a crystalline phase embedded in an amorphous glass matrix. The crystalline phase includes eucryptite and at least one lithium silicate-based crystalline phase selected from the group consisting of lithium metasilicate and lithium disilicate. The dental bulk block is a functionally graded material having a crystalline size gradient with respect to a depth thereof and having no interface at a point of change in main crystalline size gradient value. The bulk block that is heat-treated at 820° C. for 40 minutes exhibits a characteristic peak of a spodumene crystalline phase in an X-ray diffraction analysis result graph unlike the bulk block that is heat-treated at 820° C. for 2 minutes.

Abstract: Provided is a machinable abutment-integrated prosthetic block. The machinable abutment-integrated prosthetic block is structured such that an abutment is integrated with a crown block made of a material requiring no heat treatment after undergoing machining processing. The abutment and the crown block are integrated by an adhesive layer containing a cured product of a polymerizable organic compound. Therefore, the prosthetic block which is an integrated form of the abutment and the crown block can be processed by machining processing such as CAD/CAM processing. Therefore, the prosthetic block can be processed, by machining processing, into artificial teeth to be used as temporary teeth or permanent teeth and does not require no additional heat treatment after undergoing the machining processing, thereby shortening a treatment time for implant restoration, resulting in a one-day prosthesis procedure.

Abstract: Dental prosthesis having a structure similar to that of natural teeth and a method for manufacturing the same. Provided is a dental prosthesis capable of expressing a structure and properties similar to natural teeth in which enamel is a surface layer and dentine is an inner layer underneath the enamel. In addition, a method of manufacturing the same dental prosthesis through three-dimensional printing is provided. The dental prosthesis is a cured product including ceramic particles dispersed in a polymer matrix. The cured product includes a first cured product layer including 70% to 90% by weight of ceramic particles having an average particle diameter of 100 to 1,000 nm and a second cured product layer including 40% to 60% by weight of ceramic particles having an average particle diameter of 10 ?m to 500 ?m, the second cured product layer being adjacent to the inner surface of the first cured product layer.

Abstract: Provided is a dental bulk block comprising a crystalline phase includes lithium disilicate as a main crystalline phase and eucryptite as a sub-crystalline phase in an amorphous glass matrix that is a functionally graded material having a main crystalline size gradient with respect to the depth thereof, and having no interface at the point of change in the main crystalline size gradient value, and is useful for manufacturing artificial teeth having structural characteristics similar to those of natural teeth, is facile to machine into an artificial tooth prosthesis due to the inclusion of eucryptite as the sub-crystalline phase compared to when only lithium disilicate exists, and can not only shorten the manufacturing time, but also increase the structural stability in terms of force distribution through functional grading of mechanical properties.

Abstract: This specification discloses a quantum public-key cryptosystem. The quantum public-key cryptosystem may use two rotation operators R{circumflex over (n)}(?) and R{circumflex over (m)}(?) satisfying a cyclic evolution. The two rotation operators R{circumflex over (n)}(?) and R{circumflex over (m)}(?) do not have a commutation relation or an anti-commutation relation with each other. The commutation relation or the anti-commutation relation is established when either of the following conditions is satisfied: ?=2i?, ?=2j?, or {circumflex over (n)}·{circumflex over (m)}=1 (i, j=integer), and ?=(2k+1)?, ?=(2l+1)?, or {circumflex over (n)}·{circumflex over (m)}=0 (k, l=integer).

Abstract: A dental bulk block for a CAD/CAM machining process. The dental bulk block is a glass-ceramic block having a crystalline phase embedded in an amorphous glass matrix. The crystalline phase includes lithium disilicate as a main crystalline phase, no sub-crystalline phase exists, and the crystalline phase has a mean grain size of 0.01 to 1.0 ?m and a crystallinity degree of 25 to 45%. The dental bulk block can improve machinability during cutting such as CAD/CAM machining in the state of a high-strength workpiece with high flexural strength, thereby reducing a tool resistance and a wear rate, increasing a tool life span, and reducing edge chipping during a machining process. In addition, a dental restoration with desired translucency variations can be manufactured through a simple process of machining a block and altering post-heat treatment conditions, and thus can be realized with various shades.

Abstract: A crystallized glass includes crystalline and vitreous structures, in which the crystalline structure includes lithium disilicate as a main crystalline phase and at least one crystalline phase among lithium phosphonate (Li3PO4), lithium metasilicate (Li2SiO3), silica (SiO2), and zirconia (ZrO2) as a sub-crystalline phase, has an excellent processability and an excellent plasma corrosion resistance, thereby being useful as a material for production of parts for various dry etching apparatuses.

Abstract: Provided is a silicate glass, a method for preparing a silicate glass-ceramics by using the silicate glass, and a method for preparing a lithium disilicate glass-ceramics by using the silicate glass, and more particularly, to a method for preparing a glass-ceramics that has a nanosize of 0.2 to 0.5 ?m and contains lithium disilicate and silicate crystalline phases. A nano lithium disilicate glass-ceramics containing a SiO2 crystalline phase includes: a glass composition including 70 to 85 wt % SiO2, 10 to 13 wt % Li2O, 3 to 7 wt % P2O5 working as a nuclei formation agent, 0 to 5 wt % Al2O3 for increasing a glass transition temperature and a softening point and enhancing chemical durability of glass, 0 to 2 wt % ZrO2, 0.5 to 3 wt % CaO for increasing a thermal expansion coefficient of the glass, 0.5 to 3 wt % Na2O, 0.5 to 3 wt % K2O, and 1 to 2 wt % colorants, and 0 to 2.0 wt % mixture of MgO, ZnO, F, and La2O3.

Abstract: Disclosed is a machinable dental bulk block that is a glass ceramic block including an amorphous glass matrix and crystalline phases introduced into the matrix. A major crystalline phase is lithium disilicate and a minor crystalline phase is lithium phosphate. The dental block is made of a functionally gradient material in which the major crystalline phase exhibits a gradient of particle sizes in a depth direction of the dental block and which has no interface at a point where the gradient of particle sizes of the major crystalline phase changes. The dental bulk block is useful for production of a dental prosthesis (artificial tooth) similar to a natural tooth. The dental bulk block can reduce time and the number of processing steps to manufacture a dental prosthesis and provides improved structural stability through good force distribution obtained by functionally graded mechanical properties.

Abstract: Disclosed is a machinable dental bulk block that is a glass ceramic block including an amorphous glass matrix and crystalline phases introduced into the matrix. A major crystalline phase is lithium disilicate and minor crystalline phases are lithium phosphate and at least one of spodumene and virgilite. The dental block is made of a functionally gradient material in which the major crystalline phase exhibits a gradient of particle sizes in a depth direction of the dental block and which has no interface at a point where the gradient of particle sizes of the major crystalline phase changes. The dental bulk block is useful for production of a dental prosthesis (artificial tooth) similar to a natural tooth. The dental bulk block can reduce time and the number of processing steps to manufacture a dental prosthesis and provides improved structural stability through good force distribution obtained by functionally graded mechanical properties.

Abstract: Provided is a dental blank. The dental blank includes: a seating portion provided in an artificial tooth processing apparatus; and a material portion configured to be inserted into the seating portion, wherein the material portion includes a plurality of outer contacting portions in contact with an inner side of the seating portion, and may have a polygonal shape in a cross-section.

Abstract: An inverted nanocone structure of the present disclosure includes a first surface, a second surface spaced apart from the first surface by a predetermined distance and having a greater area than the first surface, and a body having an inverted cone shape between the first surface and the second surface, wherein at least one activated point defect center is provided in the body.

Abstract: Provided is a dental bulk block for grinding processing. The dental bulk block includes a crystalloid, which includes lithium disilicate as a main crystal phase and silicate as a sub-crystal phase, and hyaline as a remainder. The dental bulk block is a functionally gradient material having a crystalline size gradient with respect to a depth thereof and having no interface at a change point of a crystalline size gradient value. The dental bulk block is useful for manufacturing an artificial dental prosthesis that is similar to natural teeth. Accordingly, the time and process for manufacturing the artificial dental prosthesis are shortened, and structural stability is increased in terms of dispersion of force due to gradient functionalization of mechanical properties.

Abstract: Dental composite composition including a glass ceramic and a curable organic material is described in which the glass ceramic includes a crystal phase having an average grain size of 50 to 400 nm, and the dental composite composition is provided as a dental prosthetic material exhibiting superior transparency and mechanical properties comparing to conventional composite products containing micro-sized crystal grains and also has excellent aesthetics and processability required for prosthetic materials for same-day dental prosthetic service.

Abstract: The present invention provides a random number generation system comprising: an image sensor module for outputting dark noise generated from each unit pixel region respectively that is shielded from external light as digital data; and a control unit for classifying the respective pieces of digital data output from the image sensor module, for allocating random numbers to the same using a database in which a plurality of reference values are stored for each unit pixel, and for collating the same so as to generate a first random number.