Lithium silicate materials are described which can be easily processed by machining to dental products without undue wear of the tools and which subsequently can be converted into lithium silicate products showing high strength.

Lithium silicate materials are described which can be easily processed by machining to dental products without undue wear of the tools and which subsequently can be converted into lithium silicate products showing high strength.

The present invention relates to a method of fabricating an improved lithium silicate glass ceramic and to that material for the manufacture of blocks for dental appliances using a CAD/CAM process and hot pressing system. The lithium silicate material has a chemical composition that is different from those reported in the prior art with 1 to 10% of germanium dioxide in final composition. The softening points are close to the crystallization final temperature of 800 C. indicating that the samples will support the temperature process without shape deformation.

A dental block for producing a dental prosthesis comprises a green body including zirconia and having a chemical composition including increasing amounts of a chroma component, such as manganese, through a thickness of the green body. The green body is substantially white with a substantially consistent optical characteristic of chroma across the thickness, and is subsequently millable and sinterable to form the dental prosthesis with an optical characteristic of decreasing gray color through a thickness of the dental prosthesis.

A dental block for producing a dental prosthesis comprises a green body including zirconia and having a chemical composition including increasing amounts of a chroma component, such as manganese, through a thickness of the green body. The green body is substantially white with a substantially consistent optical characteristic of chroma across the thickness, and is subsequently millable and sinterable to form the dental prosthesis with an optical characteristic of decreasing gray color through a thickness of the dental prosthesis.

The present invention provides an alumina pre-sintered body that demonstrates reduced yellowing after sintering, exhibits high translucency and high linear light transmittance in the sintered body even when sintered under atmospheric pressure, and yields an alumina sintered body with high aesthetics suitable for dental applications. The present invention relates to an alumina pre-sintered body for dental use comprising alumina particles with an average primary particle diameter of 30 to 300 nm, a sintering aid, and a bluish colorant, wherein the content of the sintering aid is 10 to 5,000 ppm.

The present invention provides a zirconia pre-sintered body having suitable shades, translucency, and strength. The present invention relates to a zirconia pre-sintered body comprising a layered structure of at least three layers containing zirconia and a stabilizer capable of preventing a phase transformation of zirconia, the layered structure including at least two layers that differ from one another in the content of the stabilizer relative to the total mole of the zirconia and the stabilizer, the layered structure including at least two layers having substantially the same stabilizer content relative to the total mole of the zirconia and the stabilizer, the zirconia pre-sintered body containing a coloring component in all of the layers having substantially the same stabilizer content, and the layers having substantially the same stabilizer content differing from one another in the composition of the coloring component.

A multi-layer porcelain block includes a first zirconia powder layer, a second zirconia powder layer, a third zirconia powder layer, a fourth zirconia powder layer, a fifth zirconia powder layer, a sixth zirconia powder layer, a seventh zirconia powder layer, and an eighth zirconia powder layer laid in sequence. The zirconia powders in the first to eighth zirconia powder layers are doped with yttria. The first zirconia powder layer accounts for 13% to 17% by mass, the second zirconia powder layer accounts for 8% to 12% by mass, the third zirconia powder layer accounts for 10% to 14% by mass, the fourth zirconia powder layer accounts for 10% to 14% by mass, the fifth zirconia powder layer accounts for 10% to 14% by mass, the sixth zirconia powder layer accounts for 10% to 14% by mass.