Lithium silicate glass ceramics and glasses containing specific oxides of divalent elements are described which crystallize at low temperatures and are suitable in particular as dental materials.

The invention relates to a process for selectively treating parts of the surface of a porous dental zirconia article, the process comprising the steps of providing a liquid composition and a porous 3-dimensional dental zirconia article having an outer and inner surface, applying the liquid composition to only a part the outer surface and/or inner surface of the porous dental zirconia article, the liquid composition comprising a whitening agent comprising a phosphorous containing component, the phosphorous containing component comprising a phosphate, phosphone or phosphine moiety, with the proviso that at least one PO unit of the phosphate, phosphone or phosphine moiety is dissociable or able to otherwise interact with zirconia. The invention also relates to a dental zirconia article obtainable or obtained by such a process and a kit of parts comprising a container containing a certain liquid composition.

A method for producing dentures uses a green compact containing a mixture of ceramic powder and a binder system. A ceramic shell for dentures can be produced from the green compact and can be shaped and can be adapted to a carrier prior to a firing step below a temperature of 1050 C.

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.

ZrO.sub.2-toughened glass ceramics having high molar fractions of tetragonal ZrO2 and fracture toughness value of greater than 2 MPa.Math.m.sup.1/2. The glass ceramic may also include also contain other secondary phases 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.

The present invention is directed to a porous pre-densified CeO.sub.2 stabilized ZrO.sub.2 ceramic having a density of 50.0 to 95.0%, relative to the theoretical density of zirconia, and an open porosity of 5 to 50% as well as to ceramic having a density of 97.0 to 100.0%, relative to the theoretical density of zirconia, and wherein the grains of the ceramic have an average grain size of 50 to 1000 nm, methods for the preparation of the pre-densified and densified ceramics and their use for the manufacture of dental restorations.

There is provided an oral biofilm inhibitor having an exceptional inhibitory effect on oral biofilm formation. It is an oral biofilm inhibitor comprising a curable composition containing an antimicrobial agent, wherein a compressive strength of a cured product formed by curing the composition is 150 MPa or less, and a content of the antimicrobial agent is 0.001 to 3% by weight. An oral biofilm inhibitor thus obtained is used for inhibiting biofilm formation in an oral cavity by applying a curable composition containing an antimicrobial agent to a dental defect site for allowing the composition to cure at the dental defect site, and then disintegrating the cured composition.

To provide a two-paste type sealer composition for root canal filling consisting of a first paste containing a polymer (a) of an acid group-containing polymerizable monomer in which a portion or the entirety of the acidic group in a molecule forms a salt with an alkaline metal, a non-acid reactive powder (b) and water (c), wherein the pH of the first paste is in the range from 3.5 to 5.5, and a second paste containing an acid reactive inorganic powder (d), water (c) and a thickener (e), wherein, a cured product of a kneaded material of the first paste and the second paste comprises 3 to 20 part by weight of the polymer (a), 15 to 60 part by weight of the water (c), and 30 to 70 part by weight of the acid reactive inorganic powder (d).

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.

Kits of parts comprising a coloring solution, a porous zirconia article, optionally application equipment, the solution comprising cation(s) of coloring agent(s) in an amount above about 0.05 mol/l, solvent(s) for the ion(s), optionally complexing agent(s), optionally thickening agent(s), optionally organic marker substance(s), optionally additive(s), the porous zirconia article showing a N2 adsorption and desorption of isotherm type IV according to IUPAC classification. Methods for coloring a zirconia article comprising the steps of providing a porous zirconia article and a coloring solution, applying the coloring solution to at least a part of the outer surface of the porous zirconia article, optionally drying the porous zirconia article of the preceding step, sintering the porous zirconia article to obtain a colored zirconia ceramic article.