Lithium silicate-wollastonite glass ceramics are described which are characterized by a controllable translucence and can be easily machined and therefore can be used in particular as restoration material in dentistry.

Lithium silicate-low quartz glass ceramics are described which are characterized by a combination of very good mechanical and optical properties and can therefore be used in particular as restoration material in dentistry.

Disclosed herein are curable glass ionomer compositions that include a first paste and a second paste, and methods for using the disclosed compositions. The first paste includes water, a polyacid, and a non acid-reactive filler. The second paste includes water, an acid-reactive filler; and non-aggregated, water-miscible, nano-sized silica particles having at least 25% surface coverage of the particles with a silane. The composition is essentially free of a resin. In some embodiments, the water content of the first paste and the second paste of the paste/paste GI composition disclosed herein is less than 20% by weight, based on the total weight of the composition.

The invention relates to a process for the preparation of a glass-ceramic blank for dental purposes with lithium silicate as crystal phase, in which lithium silicate blanks that are no longer required and in particular residues thereof are used as starting material and which allows the production of a homogeneous starting glass within a short time.

The present invention provides a material composition and a process of producing translucent ZrO.sub.2SiO.sub.2nanocrystalline glass ceramic (NCGC) with ultra-high flexural strength. The method comprises the following step: (1) prepare homogenous ZrO2-SiO2 nano-sized powder with high purity via a sol-gel method; (2) pressure assisted sintering of ZrO2-SiO2 nano-sized sol-gel powder to obtain translucent ZrO2-SiO2 NCGC. The invention also includes materials manufactured using the method.

The present invention relates to a method for preparing a lithium disilicate glass-ceramics containing silicate as a main component, and more particularly, to a method for preparing a glass-ceramics, which is capable of adjusting machinability or translucency according to a crystalline size by using a first heat treatment or a second heat treatment. To this end, a method for preparing a glass-ceramics containing a silica crystalline phase includes: performing a first heat treatment on a glass composition at a temperature of 400 to 850 C., so that a lithium disilicate crystalline phase and a silica crystalline phase each having a size of 5 to 2,000 nm are formed through the first heat treatment. After the first heat treatment, the method further includes performing a second heat treatment at a temperature of 780 to 880 C., so that translucency is adjusted by a temperature of the second heat treatment.

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.

Provided is a method for preparing a lithium disilicate glass-ceramics containing silicate as a main component, and more particularly, to a method for preparing a glass-ceramics, which is capable of adjusting machinability or translucency according to a crystalline size by using a first heat treatment or a second heat treatment. To this end, a method for preparing a glass-ceramics containing a silica crystalline phase includes: performing a first heat treatment on a glass composition at a temperature of 400 to 850 C., so that a lithium disilicate crystalline phase and a silica crystalline phase each having a size of 5 to 2,000 nm are formed through the first heat treatment. After the first heat treatment, the method further includes performing a second heat treatment at a temperature of 780 to 880 C., so that translucency is adjusted by a temperature of the second heat treatment.

The invention relates to a method for producing a monolithic form body, in particular a dental restoration, comprising the steps of: providing of a blank, producing of the form body through pressing and/or machining of the blank, and softening of the form body exclusively in its surface region by irradiation with infrared radiation.

The invention relates to a method for the production of a restoration from a blank consisting of, or containing, a lithium silicate glass ceramic, wherein at least two layers of ceramic material of different compositions are filled into a mold layer-by-layer and after filling of the layers they are then pressed and sintered, wherein after filling of a first layer this is structured on its surface in such a way that the first layer, viewed across its surface, differs in its height from region to region, and then a layer with a composition that differs from the first layer is filled as a second layer into the mold. After sintering the dental restoration is produced from the blank by mechanical working.