The present invention relates to a composition for a single-paste type hydraulic endodontic filling material comprising dimethyl sulfoxide (DMSO). According to one aspect of the invention, there is provided a single-paste type hydraulic endodontic filling composition, comprising a calcium silicate component and DMSO.

A powder intended for the manufacture of a sintered dental article, The powder has a chemical analysis such that, as weight percentages based on the oxides: Al.sub.2O.sub.3: 0.2%, oxides other than ZrO.sub.2, HfO.sub.2, Yb.sub.2O.sub.3, Y.sub.2O.sub.3 and Al.sub.2O.sub.3: <0.5%, and ZrO.sub.2+HfO.sub.2+Yb.sub.2O.sub.3+Y.sub.2O.sub.3: balance to 100%, with HfO.sub.2<2%. The contents of Yb.sub.2O.sub.3 and Y.sub.2O.sub.3, as molar percentages based on the sum of ZrO.sub.2, HfO.sub.2, Yb.sub.2O.sub.3 and Y.sub.2O.sub.3, being such that Yb.sub.2O.sub.3≥1%, 0.5%≤Y.sub.2O.sub.3<2%, and Yb.sub.2O.sub.3+Y.sub.2O.sub.3≤5.5%. The powder has a specific surface area of greater than or equal to 5 m.sup.2/g and less than or equal to 16 m.sup.2/g. The powder has a median size of greater than or equal to 0.1 μm and less than or equal to 0.7 μm.

A powder intended for the manufacture of a sintered dental article, The powder has a chemical analysis such that, as weight percentages based on the oxides: Al.sub.2O.sub.3: 0.2%, oxides other than ZrO.sub.2, HfO.sub.2, Yb.sub.2O.sub.3, Y.sub.2O.sub.3 and Al.sub.2O.sub.3: <0.5%, and ZrO.sub.2+HfO.sub.2+Yb.sub.2O.sub.3+Y.sub.2O.sub.3: balance to 100%, with HfO.sub.2<2%. The contents of Yb.sub.2O.sub.3 and Y.sub.2O.sub.3, as molar percentages based on the sum of ZrO.sub.2, HfO.sub.2, Yb.sub.2O.sub.3 and Y.sub.2O.sub.3, being such that Yb.sub.2O.sub.3≥1%, 0.5%≤Y.sub.2O.sub.3<2%, and Yb.sub.2O.sub.3+Y.sub.2O.sub.3≤5.5%. The powder has a specific surface area of greater than or equal to 5 m.sup.2/g and less than or equal to 16 m.sup.2/g. The powder has a median size of greater than or equal to 0.1 μm and less than or equal to 0.7 μm.

A method for producing a zirconia sintered body includes: heating a zirconia molded body or a zirconia pre-sintered body, the heating includes a temperature increasing step, and a rate of temperature increase in a temperature region from a temperature at which the zirconia starts to shrink to a temperature at which the zirconia finishes shrinking in the temperature increasing step is adjusted to enable the zirconia molded body or the zirconia pre-sintered body to shrink at substantially a constant rate during temperature increase in each of zones of when the temperature region is evenly divided into a plurality of zones of specific temperature ranges.

A method for producing a zirconia sintered body includes: heating a zirconia molded body or a zirconia pre-sintered body, the heating includes a temperature increasing step, and a rate of temperature increase in a temperature region from a temperature at which the zirconia starts to shrink to a temperature at which the zirconia finishes shrinking in the temperature increasing step is adjusted to enable the zirconia molded body or the zirconia pre-sintered body to shrink at substantially a constant rate during temperature increase in each of zones of when the temperature region is evenly divided into a plurality of zones of specific temperature ranges.

The invention relates to a dental opaquer composition which can be used to increase the opacity of zirconium oxide ceramics. In addition, the invention relates to a process for producing a dental restoration, in which the opacity of the zirconium oxide ceramic is increased by using the opaquer composition.

The invention relates to a dental opaquer composition which can be used to increase the opacity of zirconium oxide ceramics. In addition, the invention relates to a process for producing a dental restoration, in which the opacity of the zirconium oxide ceramic is increased by using the opaquer composition.

ZrO.sub.2-toughened glass ceramics having high molar fractions of tetragonal ZrO.sub.2 and fracture toughness value of greater than 1.8 MPa.Math.m.sup.1/2. The glass ceramic may also include also contain other secondary phases, including lithium silicates, that may be beneficial for toughening or for strengthening through an ion exchange process. Additional second phases may also decrease the coefficient of thermal expansion of the glass ceramic. A method of making such glass ceramics is also provided.

ZrO.sub.2-toughened glass ceramics having high molar fractions of tetragonal ZrO.sub.2 and fracture toughness value of greater than 1.8 MPa.Math.m.sup.1/2. The glass ceramic may also include also contain other secondary phases, including lithium silicates, that may be beneficial for toughening or for strengthening through an ion exchange process. Additional second phases may also decrease the coefficient of thermal expansion of the glass ceramic. A method of making such glass ceramics is also provided.

Dental material, which contains at least one radically polymerizable monomer, at least one radiopaque filler, at least one composite filler, at least one inorganic filler and at least one initiator for the radical polymerization. The dental material is particularly suitable as dental filling material.