Abstract: High strength ceramic components for use in dental applications are provided with a bonding layer disposed thereon to increase the bonding properties of the ceramic component in order that the ceramic component may better bond to a resin material, ceramic material or composite material. Moreover, the bonding layer provides strength to the ceramic component by forming a compressive layer thereon. The ceramic component may be partially or fully embedded in composite material. The ceramic component is bonded to the composite material either by mechanical means, chemical means or both. The material may be placed directly on the ceramic component. Alternatively, the structural component is coated with a bonding layer to provide adhesion between the composite or like material and the structural component.

Abstract: Blocks or blanks of material comprise indicia to indicate the properties of the material. The blanks are designed for use in computer assisted milling machines whereby the machines can interpret the indicia and accomplish the milling process required for the blank being used. The milling process used will depend upon the information provided in the indicia. Preferably, the blocks are milled into shapes for use as dental restorations.

Abstract: Solid free form fabrication techniques such as fused deposition modeling and three-dimensional printing are used to create a shell used in the manufacture of a dental restoration. Three-dimensional printing comprises ink-jet printing a binder into selected areas of sequentially deposited layers of powder. Each layer is created by spreading a thin layer of powder over the surface of a powder bed. Instructions for each layer may be derived directly from a CAD representation of the restoration. The area to be printed is obtained by computing the area of intersection between the desired plane and the CAD representation of the object. All the layers required for an aesthetically sound shell can be deposited concurrently slice after slice and sintered/cured simultaneously.

Abstract: Micaceous glass-ceramics are useful in the fabrication of single and multi-unit dental restorations including but not limited to orthodontic appliances, bridges, space maintainers, tooth replacement appliances, splints, crowns, partial crowns, dentures, posts, teeth, jackets, inlays, onlays, facing, veneers, facets, implants, abutments, cylinders, and connectors by machining the glass-ceramic using CAM/CAM devices. The micaceous glass-ceramics are provided in a plurality of shades and colors to adequately match the colors and shades of teeth found in 95% or more of the human population.

Abstract: Solid free form fabrication techniques such as fused deposition modeling and three-dimensional printing are used to create a dental restoration. Three-dimensional printing comprises inkjet printing a binder into selected areas of sequentially deposited layers of powder. Each layer is created by spreading a thin layer of powder over the surface of a powder bed. Instructions for each layer may be derived directly from a CAD representation of the restoration. The area to be printed is obtained by computing the area of intersection between the desired plane and the CAD representation of the object. All the layers required for an aesthetically sound restoration can be deposited concurrently slice after slice and sintered/cured simultaneously. The amount of green body oversize is equivalent to the amount of shrinkage which occurs during sintering or curing.

Abstract: Ceramic precursor powders are combined with a binder and pressed into blocks or similar shapes to form green bodies. The ceramic powders consist of fairly uniform particles thoroughly dispersed to be essentially free of agglomerates such that it will sinter predictably and isotropically without appreciable distortion. The green bodies may be soft-sintered to a bisque density less than about eighty five percent of the final density. The soft-sintered blocks are then milled to a desired shape and sintered to a final density rendering a high strength dental restorative material. The material may be aluminum oxide, partially stabilized zirconium oxide, mixtures of the two, mullite or any suitable oxide that may be sintered to high strength (i.e., greater than 250 MPa).

Abstract: Blocks of material are prepared in a variety of shapes and sizes to be used in the fabrication of models for dental restorations. The material comprises a partially sintered ceramic material. The blocks are used to manufacture molds using CAD/CAM methods and equipment. The molds are useful in the manufacture of dental restorations using ceramics, metals, alloys, or powders thereof, and composite materials. The models milled from the blanks may be used to manufacture a variety of dental restorations including, but not limited to, crowns, bridges, space maintainers, tooth replacement appliances, orthodontic retainers, dentures, posts, jackets, inlays, onlays, facings, veneers, facets, implants, abutments, splints, partial crowns, teeth, cylinders, pins, and connectors.

Abstract: Solid free form fabrication techniques such as fused deposition modeling and three-dimensional printing are used to create a dental restoration. Three-dimensional printing includes ink-jet printing a binder into selected areas of sequentially deposited layers of powder. Each layer is created by spreading a thin layer of powder over the surface of a powder bed. Instructions for each layer may be derived directly from a CAD representation of the restoration. The area to be printed is obtained by computing the area of intersection between the desired plane and the CAD representation of the object. All the layers required for an aesthetically sound restoration can be deposited concurrently slice after slice and sintered/cured simultaneously. The amount of green body oversize is equivalent to the amount of shrinkage which occurs during sintering or curing.

Abstract: A method and apparatus for producing dental restorations for teeth that need to be restored. In the process, a first set of data points is retrieved from a tooth or an image of the tooth to be restored. The tooth is prepared by the dentist and a second set of data points is retrieved from the tooth or an image of the tooth. The second set of points is compared to the first set of points to obtain a third set of points. The dental restoration is milled from dental material based on the image resulting from the third set of data points.

Abstract: Porcelain compositions of the present invention comprises particulate of one or more glass or glass-ceramic powder components. Additionally, one or more opacifing agents, pigments, fluorescing agents and the like may be included in the composition. Based on volume percent, the particulate has a d10 of from about 1.1 and about 1.8 microns; a d50 of from about 3 to about 6 microns; a d90 of from about 8 to about 16 microns; and about 1.0 to about 4.0% by volume of the particulate has a particle size greater than or equal to about 20 microns. The mean particle size is preferably in the range of about 3.0 microns to about 7.5 microns.

Abstract: A dental restoration comprising a porcelain composition, comprising a glassy matrix and leucite crystallites embedded therein, and having maturing temperatures in the range from about 680.degree. C. to about 870.degree. C. and CTEs in the range from about 12 to about 15, more preferably in the range from about 12.5 to about 14.5, and most preferably in the range from about 13.1 to about 14.5.times.10.sup.-6 /.degree. C. (measured from 25.degree. C. to 470.degree. C.). The porcelain is used in combination with a ceramic core or metal framework. The ceramic core comprises cubic leucite and exhibits maturing temperatures less than about 1200.degree. C. and CTEs in the range of about 12.5 to about 15.0.times.10.sup.-6 /.degree. C. (measured from 25.degree. C. to 500.degree. C.).

Abstract: A method for producing a machinable feldspathic porcelain comprising leucite is presented. Machinability is imparted to feldspathic porcelains by achieving homogeneous distribution of fine crystalline constituent comprised of at least one of the following leucite phases: potassium tetragonal leucite, rubidium leucite, cesium stabilized cubic leucite, rubidium stabilized cubic leucite, and pollucite. The porcelains produced in accordance with the present invention are readily machinable by using available diamond tooling techniques. Furthermore, the porcelains are especially useful for the fabrication of dental restorations using CAD/CAM technology.

Abstract: A dental porcelain composition comprising a continuous glassy phase and a discontinuous, substantially uniform crystalline phase comprising cubic leucite. The porcelain exhibits coefficients of thermal expansion in the range of about 11 to about 17.times.10.sup.-6 /.degree. C. (measured from 25.degree. C. to 500.degree. C.) and fusion temperatures in the range of about 700.degree. C. to about 1200.degree. C. The porcelain composition of the present invention can be used to form dental restorations such as cores for all ceramic restorations. The cubic leucite phase is uniformly dispersed in the glass matrix and has an average grain size not exceeding about 4 .mu.m and about 95% of the leucite grains do not exceed about 8 .mu.m in diameter.

Abstract: Porcelain compositions of the present invention possess non-greening properties and comprise one or more glass or glass-ceramic components. Additionally, an oxygen release agent is included in the compositions. The porcelain compositions may vary depending upon the specific thermal properties desired.The application temperature of the porcelain compositions ranges from about 600.degree. C. to about 930.degree. C. depending upon the method of application of the porcelain. The coefficient of thermal expansion is preferably in the range of about 11.times.10.sup.-6 /.degree. C. to about 16.times.10.sup.-6 /.degree. C. The porcelain is compatible with cores and/or substrates having coefficients of thermal expansion in the range of about 11 to about 20.times.10.sup.-6 /.degree. C.

Abstract: A dental porcelain composition, comprising a glassy matrix and rubidium leucite crystallites embedded therein, and having maturing temperatures in the range from about 650.degree. C. to about 800.degree. C. and CTEs in the range from about 13 to about 17, more preferably in the range from about 13.5 to about 16, and most preferably in the range from about 14 to about 16.times.10.sup.-6 /.degree. C. (measured from 25.degree. C. to 400.degree. C.). The tetragonal rubidium leucite is preferably both fine-grained (i.e., having average diameters of less than about 5 microns) and uniformly sized. Preferably, the average diameters are less than about 1 to about 2 microns.

Abstract: The present invention relates to a method for preparing the color of a dental restoration using a spectrophotometer and a unique color system for porcelain dental restorations which enables a dentist or technician to manipulate the various color components of the porcelain, hue, chroma, value, and translucency, independently. Color component deltas between consecutive colors in the powder sets are equidistant, with the difference in values being linear in color space. This enables simplified, exact matching of a specified color component value. The method comprises illuminating an abutting tooth with light, gathering reflected light, converting the gathered light to analog signals, correct for ambient light interference, translucency effects (if necessary) and varying illumination, using the result to obtain accurate color component values, and employing those values to chose and, where necessary, mix the appropriate powers to obtain the correct color porcelain for the desired dental restoration.

Abstract: Porcelain compositions of the present invention comprise one or more glass or glass-ceramic powder components. Additionally, one or more opacifying agents, pigments, fluorescing agents and the like may be included in the composition. Based on volume percent, 10% of the particulate in the porcelain has a particle size of less than between about 1.1 microns and about 1.5 microns, 50% of the particulate in the porcelain has a particle size of less than between about 3 and about 6 microns, 90% of the particulate in the porcelain has a particle size of less than between about 8 and about 13.5 microns, and the maximum particle size of the particulate is greater than about 20 microns and less than about 60 microns. The mean particle size is preferably in the range of about 3.0 microns to about 6.5 microns.

Abstract: A porcelain composition for dental restorations comprising a leucite crystallite phase and a glass matrix phase, wherein the leucite crystallites possess diameters not exceeding about 10 micron. Preferably, the porcelain composition has a maturing temperature from about 750.degree. to about 1050.degree. C. and a coefficient of thermal expansion from about 12.times.10.sup.-6 /.degree. C. to about 17.5.times.10.sup.-6 /.degree. C., and comprises:______________________________________ Component Amount (wt. %) ______________________________________ SiO.sub.2 57-66 Al.sub.2 O.sub.3 7-15 K.sub.2 O 7-15 Na.sub.2 O 7-12 Li.sub.2 O 0.5-3.

Abstract: A method of making a dental porcelain restoration comprises providing a soft-sintered dental porcelain pellet; milling the soft-sintered pellet under the control of a CAD/CAM system to provide a tooth structure; investing the tooth structure with an investment refractory material to provide an invested tooth structure; fusing the invested tooth structure; and removing the investment refractory material from the fused tooth structure to provide the dental restoration.

Abstract: A two-phase porcelain composition for dental restorations comprising a leucite crystallite phase dispersed in a feldspathic glass matrix, a maturing temperature of from about 750.degree. to about 1050.degree. C. and a coefficient of thermal expansion of from about 12.times.10.sup.-6 /.degree.C. to about 17.5.times.10.sup.-6 /.degree.C., said porcelain composition comprising:______________________________________ Component Amount (wt. %) ______________________________________ SiO.sub.2 57-66 Al.sub.2 O.sub.3 7-15 K.sub.2 O 7-15 Na.sub.2 O 7-12 Li.sub.2 O 0.5-3 CaO 0-3 MgO 0-7 F 0-4 CeO.sub.2 0-1 ______________________________________wherein the leucite crystallites possess diameters not exceeding about 10 microns and represent from about 5 to about 65 weight percent of the two-phase porcelain composition.