Abstract: The present invention provides a dental product comprising a base material formed of a zirconia sintered body, and having high aesthetic quality with enhanced fracture toughness and with reduced chipping and cracking in the porcelain layer. The present invention also provides a method for manufacturing such a dental product. The present invention relates to a dental product comprising: a base material formed of a zirconia sintered body, and a porcelain layer, wherein the porcelain of the porcelain layer has a suitable firing temperature of 900° C. or more, and the porcelain layer has a fracture toughness value of 1.20 MPa·m0.5 or more.

Abstract: The present invention provides a silicate glass that can reduce a color change in base material zirconia even when simultaneously fired with an unsintered zirconia. The present invention also provides a dental product using same. The present invention relates to a silicate glass comprising: 65.0 to 90.0 mol % SiO2, 4.0 to 15.0 mol % Al2O3, 1.0 to 10.0 mol % K2O, 0.1 to 7.0 mol % Na2O, and 0.01 to 15.0 mol % CaO, the silicate glass being essentially free of B2O3, and satisfying the relation {(number of moles of Al2O3)/(total number of moles of RO+R2O)}?0.70, wherein R in the metal oxide represented by RO represents a metallic element in group 2 or 12 of the periodic table, and R in the metal oxide represented by R2O represents a metallic element in group 1 of the periodic table. The present invention also relates to a composite comprising the silicate glass and a base material formed of a ceramic; a sintered body as a fired product of the composite; and a dental product comprising the sintered body.

Abstract: The present invention provides a silicate glass that can reduce a color change in base material zirconia even when simultaneously fired with an unsintered zirconia. The present invention also provides a dental product using same. The present invention relates to a silicate glass comprising: 65.0 to 90.0 mol % SiO2, 4.0 to 15.0 mol % Al2O3, 1.0 to 10.0 mol % K2O, 0.1 to 7.0 mol % Na2O, and 0.01 to 15.0 mol % CaO, the silicate glass being essentially free of B2O3, and satisfying the relation {(number of moles of Al2O3)/(total number of moles of RO+R2O)}?0.70, wherein R in the metal oxide represented by RO represents a metallic element in group 2 or 12 of the periodic table, and R in the metal oxide represented by R2O represents a metallic element in group 1 of the periodic table. The present invention also relates to a composite comprising the silicate glass and a base material formed of a ceramic; a sintered body as a fired product of the composite; and a dental product comprising the sintered body.

Abstract: The present invention provides a dental product comprising a base material formed of a zirconia sintered body, and having high aesthetic quality with enhanced fracture toughness and with reduced chipping and cracking in the porcelain layer. The present invention also provides a method for manufacturing such a dental product. The present invention relates to a dental product comprising: a base material formed of a zirconia sintered body, and a porcelain layer, wherein the porcelain of the porcelain layer has a suitable firing temperature of 900° C. or more, and the porcelain layer has a fracture toughness value of 1.20 MPa·m0.5 or more.

Abstract: Provided is a high-strength zirconia sintered body in which the progression of low-temperature degradation is inhibited. The zirconia sintered body contains partially-stabilized zirconia as a matrix phase and contains at least one element from among phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi). The content of the abovementioned element(s) in the zirconia sintered body ranges from 4×10?4 mol to 4×10?2 mol with respect to 1 mol of zirconium(IV) oxide. Preferably, the zirconia sintered body further contains 0.03% to 3% by mass of silicon dioxide.

Abstract: Provided is a high-strength zirconia sintered body in which the progression of low-temperature degradation is inhibited. The zirconia sintered body contains partially-stabilized zirconia as a matrix phase and contains at least one element from among phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi). The content of the abovementioned element(s) in the zirconia sintered body ranges from 4×10?4 mol to 4×10?2 mol with respect to 1 mol of zirconium(IV) oxide. Preferably, the zirconia sintered body further contains 0.03% to 3% by mass of silicon dioxide.

Abstract: The present invention provides a dental ceramic frame (10, 20, 30, 50) which is superior in terms of mechanical strength characteristics compared with conventional bridge-shaped ceramic frames that have glass joining layers or frames consisting of porous ceramics impregnated with glass.

Abstract: Disclosed is an electrode for electrical discharge used for diesinking, comprising an electrode member produced by subjecting a base and binder of gypsum hemihydrate powder and a filler of conductive metal powder to modeling and/or molding and setting into a desired form of electrode, and followed by plating the electrode member with a conductive metal; and a process for manufacturing the same, wherein a gypsum hemihydrate powder, a gypsum dihydrate powder in an amount of 1% by weight of the gypsum hemihydrate powder and a conductive metal powder are kneaded in vacuo, and water is added thereto to continue further kneading in vacuo, followed by casting into a mold having a predetermined shape transferred thereon to carry out hydration, molding and setting to provide an electrode member; after the electrode member is dried, it is plated with a conductive metal to enhance mutual continuity in the conductivity of the former conductive metal powder and also to form a thin metal layer on the surface of the electro