Abstract: The invention provides an implantable device coated with a layer of calcium phosphate and optionally one or more biologically active substances such as growth factors, lipis, (lipo)polysaccharides, hormones, proteins, antibiotics or cytostatics. The device can be obtained by a nanotechnology process comprising subjecting a substrate to a surface treatment until a surface roughness with an average peak distance (Ra value) between 10 and 1,000 nm and subjecting the roughened surface to precipitation of calcium phosphate from a solution containing calcium and phosphate ions with optional coprepitation of the biologically active substance.

Abstract: A strong, porous article useful as a bone substitute material and having an outer surface defining a shape having a bulk volume and having open interconnecting interstices extending throughout said volume and opening through said surface. The article comprises a continuous strong framework structure having interstices which interconnect throughout the bulk volume and a second continuous material occupying at least a portion of the same bulk volume as the framework structure. The second material comprises an osteoinductive and/or osteoconductive composition. This composition may be present in one of several forms. One of these is as a coating on the surface of the framework structure. A second form is in the form of a composite, intimately mixed with the framework material within the framework struts. The third form is as a porous mass within the interstices of the framework structure, having pores which are interconnecting with themselves, and with the interstices of the framework structure.

Abstract: This invention encompasses porous, nanocrystalline, biomimetic calcium phosphate coatings of the order of 2-30 microns that can be grown on metal implants. The chemical surface treatments and methods for making the calcium phosphate coatings are disclosed. Post treatment with dilute hydrogels such as phema reinforce the inorganic structure and enhance the mechanical strength of the coatings. Methods are also disclosed for adsorbing or covalently attaching growth factor proteins to derivatives of the hydrogel coated calcium phosphate coatings. Such hydrogel reinforced calcium phosphate coatings show equivalent bone tissue growth as the currently used implants and are easily resorbed. This property in combination with the immobilized growth factors is expected to enhance the process of osseointegration of the disclosed coatings.

Abstract: Alkali silicate glasses are described which, in view of their good chemical stability and their optical properties and processing properties, are particularly suitable as a coating or veneering material for ceramic dental frameworks and hence for the production of all-ceramic dental restorations such as crowns or bridges.

Abstract: A fabric made of fibers of a carbon-precursor cellulose material is impregnated with a composition containing at least one inorganic ingredient having a function of promoting dehydration of cellulose, and the fabric is subjected to heat treatment. This treatment consists in raising temperature at a speed lying in the range 1.degree. C./min to 15.degree. C./min followed by keeping the temperature constant in the range 350.degree. C. to 500.degree. C., and it is followed by a step of washing the fabric. This produces directly an activated fabric of carbon fibers having a specific surface area of not less than 600 m.sup.2 /g, without subsequent activation treatment at a higher temperature.

Abstract: The present invention is a method of coating a substrate with a calcium phosphate compound using plasma enhanced MOCVD. The substrate is a solid material that may be porous or non-porous, including but not limited to metal, ceramic, glass and combinations thereof. The coated substrate is preferably used as an implant, including but not limited to orthopaedic, dental and combinations thereof. Calcium phosphate compound includes but is not limited to tricalcium phosphate (TCP), hydroxyapatite (HA) and combinations thereof. TCP is preferred on a titanium implant when implant resorbability is desired. HA is preferred when the bone bonding of new bone tissue into the structure of the implant is desired. Either or both of TCP and/or HA coated implants may be placed into a solution with an agent selected from the group of protein, antibiotic, antimicrobial, growth factor and combinations thereof that can be adsorbed into the coating before implantation.

Abstract: A process for the preparation of a microsphere comprising a coating composed of one or more silica nanoparticles layers, comprises the steps of: a) providing a microsphere of polymeric material, the said microsphere having adsorbed on its surface one or more surfactants; and b) causing a layer of silica nanoparticles to coat the surface of the said microsphere by means of seeded polymerization of alkyl silicates onto the surface of said microsphere.

Abstract: The invention relates to a method for manufacturing a fiber-reinforced bioactive ceramic implant, wherein a base form is made from fibrous material and interspaces between the different fibers are filled using chemical vapor phase infiltration. Preferably, a calcium-phosphate compound is brought between the fibers, which are preferably of the continuous-fiber type.

Abstract: The invention relates to a composite composed of a plastic substrate and a thin, continuous metal-containing layer, characterised in that the metal-containing layer is ductile, adheres firmly to the plastic substrate, has a thickness of <2 .mu.m and is composed of a compound corresponding to the formulaM.sub.a O.sub.b C.sub.x N.sub.y B.sub.zwherein:M means one or more metals from the group comprising Ti, Ta, Nb, Zr and Hf,a=0.025 to 0.9b=0.025 to 0.7x=0.2 to 0.9y=0 to 0.7z=0 to 0.7a+b+x+y+z=1provided that the value of a, starting from the substrate surface, increases from a value approximating zero towards to the layer surface, and at least 50% of the carbon atoms at the base of the layer are bound to other carbon atoms by C--C bonds.

Abstract: The present invention provides a method for growing or depositing artificial bone materials called organoapatites on a metal surgical alloy. The method involves pretreating the alloy with at least one aqueous solution of a poly(amino acid). After this pretreatment step, the organoapatites can be synthesized onto the alloy. Because most surgical implants are made from metal alloys, this method can be used to make implants which contain organoapatites may promote the formation of natural bone when placed into a human patient in vivo.

Abstract: A process for forming a uniform, boron nitride coating on a boron-doped, refractory carbide body, and in particular on a sintered, boron-doped, silicon carbide fiber, where the body is exposed to a nitrogen-containing atmosphere at a temperature equal to or greater than the densification or sintering temperature. The coated fibers exhibit no loss in strength properties and show improved creep resistance.

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 process for manufacturing a phosphorescent screen for use in a cathode ray or field emission display, is described. The phosphor layer is applied in the form of a slurry consisting of a powdered phosphor, an ethylene glycol monobutyl ether acetate solvent, and a cellulose acetate butyrate binder. The phosphor concentration is between 30 and 60% by weight, the solvent between 5 and 52.5% and the binder between 17.5 and 35%. If the slurry composition falls within these ranges, then, once the aluminum anode layer is in place, all organic material can be removed by firing at a temperature that is less than 500.degree. C. By keeping the firing temperature below 500.degree. C., roughening of the undersurface of the aluminum is avoided and a more efficient screen is obtained. Data to illustrate this is also provided.

Abstract: Methods for synthesis of nanocrystalline apatites are presented, as well as a series of specific reaction parameters that can be adjusted to tailor, in specific ways, properties in the recovered product. Particulate apatite compositions having average crystal size of less than 150 nm are provided. Products also can have a surface area of at least 40 m.sup.2 /g and can be of high density.Hydroxyapatite material is investigated in particular detail. Compositions of the invention can be used as prosthetic implants and coatings for prosthetic implants.

Abstract: An improved coated orthopaedic implant component is disclosed. The implant may be coated with platinum, iridium or other metals for improved characteristics. Ion beam coating orthopaedic parts by ion implanting the parts with zirconium ions while the parts are immersed in an oxygen-containing background gas is also disclosed. The adhesion of the graded interface zirconium oxide surface layer so formed is further improved by the initial removal of surface contamination using an ion bombardment and the deposition of an intermediate layer of platinum or similar metal or silicon between the orthopaedic metal component and the zirconium oxide. Furnace heating results in atomic interdiffusion to enhance adhesion between the surfaces. The zirconium oxide provides a low friction, low wear articulating surface. The graded interface may be characterized by a blackish color and a transition between pure zirconium oxide and pure intermediate layer that extends over a thickness of hundreds of Angstroms.

Abstract: A process for the production of a hydroxyapatite coated article includes contacting a coating comprising hydroxyapatite with a recrystallization medium, pressurizing the recrystallization medium, heating the coated article under conditions of reduced oxygen activity at a temperature in the range of 100 to 350.degree. C. A process for the production of highly crystalline hydroxyapatite coated articles includes contacting a coating comprising hydroxyapatite with recrystallization medium containing hydroxyapatite particles, pressurizing the recrystallization medium, and heating the immersed coated article under conditions effective to crystallize hydroxyapatite.

Abstract: An implant includes a main body member having bio-compatibility, and particles formed of bioactive material and dispersedly provided at the surface of an embedded section of the main body member. Each of the particles has a part embedded in the embedded portion and the other part protruding from the embedded portion. The main body member is formed of titanium or titanium alloy. The particles having osteo-conduction are formed of a material selected from among a group consisting of sintered substances of hydroxylapatite, .alpha.-tricalcium phosphate, .beta.-tricalcium phosphate, tetra-calcium phosphate, a single substance of amorphous calcium phosphate, monetite, brushite, 45S4 glass, and a mixture of them. It is desirable that the embedded section surface has a surface roughness in a range of 5 to 50 .mu.m.

Abstract: A superalloy component having a substrate article of a superalloy, and a strengthenable coating covering at least a portion of the substrate article. The coating exhibits thermal barrier characteristics and when cured formed a ceramic material. The component may further include a fiber layer between the substrate article and the coating, and the coating may be reinforced with fiber and the ceramic may be imbedded with inorganic particles. The coating is a foam obtained by reacting an admixture of (a) a silane polymer, (b) a silicone-vinyl resin and (c) a catalyst. The article is preferably a turbine blade. The component is useful as a gas turbine element.

Abstract: A method is disclosed for ion beam treating orthopaedic parts by ion implanting the parts with aluminum ions while the parts are immersed in an oxygen-containing background gas. When the parts are at sufficiently elevated temperature, a highly adherent layer of aluminum oxide is grown which provides a low friction, low wear articulating surface. The interface between the semi-pure aluminum oxide and the substrate orthopaedic part consists of a composition which gradually grades with depth between the grown aluminum oxide and the pure substrate material. This interface has a thickness dependent on the processing parameters, typically hundreds of Angstroms. In an alternative embodiment, the thickness of the alumina layer may be increased by simultaneously depositing aluminum oxide on the parts.

Abstract: A battery electrode substrate which is constituted of a porous metallic body structure having communicating pores at a porosity of at least 90% and an Fe/Ni multilayer structure wherein the skeletal portion of the porous metallic body is composed mainly of Fe and has an Ni covering layer on the surface thereof while pores communicating with the inside and outside of Fe skeletal portion exist in the Fe skeletal portion and the inside of the pores is covered with Ni. The electrode substrate is produced by applying an iron oxide powder of at most 20 .mu.m in an average particle size on a porous resin core body; heat treating the core to remove an organic resin component while simultaneously sintering Fe to obtain a porous Fe body; and then covering the Fe skeletal portion with Ni by electroplating. In this process, the iron oxide can be used in combination with carbon powder. Further, a nickel porous sintered body can also be produced using nickel oxide in place of iron oxide.

Abstract: A calcium phosphate based thin film on which bone cells may be cultured to permit evaluation of bone cell functional properties comprises calcium phosphate entities which provide for varying degrees of resorption of the calcium phosphate entities in evaluating the functional properties. The film is sufficiently thin that resorption of the entities can be detected. Such film, as applied to a support, is a very useful analytical component for evaluating such bone cell functional characteristics. An analytical device, which may be used in an analytical kit, can be provided having a plurality of wells with the devices located at the bottom thereof. A process is provided for making the film and especially the film which has a combination of calcium hydroxyapatite with tricalcium phosphate.

Abstract: In order to produce lightweight mirror structures or other reflecting components, preformed silicon elements of sufficient wall thickness are applied to a CFC or CMC substrate structure with the dimensions of the component to be produced, at a temperature in the range 1300.degree. C. and 1600.degree. C. either in vacuum or in a protective atmosphere. In this way a mirror structure or reflector is formed directly. It is possible to work at temperatures in the range of 300.degree. C. to 600.degree. C. when the silicon is applied in the form of a preform such as a wafer, which is joined to the substrate by way of a zone of a melt eutectic incorporating a nonferrous metal, which is preferably gold. The surfaces are subsequently coated.

Abstract: A process for the coating of a carbon fiber composite which comprises carbon fibers bonded together with a polymeric material, which process comprises positioning the carbon fibre composite in a chamber maintained at a reduced pressure of from 25,000 to 10,000 Pa (250 to 100 mBar), and plasma spraying a coating onto a surface of the carbon fiber composite whilst cooling the said surface of the composite with an inert liquid coolant medium the said coating composition being selected from the group consisting of non-agglomerated hydroxyapatite or non-agglomerated modified hydroxyapatite.

Abstract: A process is provided for producing a bioceramic composite in which an alumina based ceramic substrate is coated with an intermediate calcium pyrophosphate layer to cement a porous calcium phosphate material to the alumina based ceramic substrate. In one aspect of the invention, the porous calcium phosphate material is a porous lattice made from natural bone. A bioceramic composite which includes an alumina-based ceramic substrate, an intermediate calcium pyrophosphate layer and a porous natural bone material bonded to the intermediate calcium pyrophosphate layer is also disclosed.

Abstract: A high quality shaped article of silicon carbide is efficiently produced by using a carbon substrate suitable for the production of a silicon carbide film without generating cracking or breakage. In a method of producing a shaped article of silicon carbide while using a carbonaceous material as a deposition substrate by decomposing halogenated organic silicone compound by a reduction pyrolysis at a high temperature, forming a silicon carbide film layer on a surface of the substrate by CVD and removing the carbon substrate, the carbon substrate is formed of a composite of graphite and amorphous carbon obtained by shaping and firing a mixture of a powdery graphite and an organic substance.

Abstract: A method of forming a protective covering on an electronic or microelectronic device to prevent inspection. A first silica-containing ceramic layer is applied to the surface of the device to planarize its surface. A second silicon carbide coating layer is applied to the surface of the first silica-containing ceramic layer to form a hermetic barrier. A third porous silica-containing ceramic layer is formed on the surface of the second silicon carbide coating layer. The third porous silica-containing ceramic layer is impregnated with an opaque material or filler. A fourth metal layer or metal pattern is applied over the third opaque porous silica-containing ceramic layer. The fourth metal layer or pattern is then coated with a fifth layer similar to the third opaque porous silica-containing ceramic layer.

Abstract: An improved process for producing a thin film of calcium phosphate entities to support bone cell activity thereon. The material to be sintered is prepared by combining a solution of ammonium phosphate with a solution of calcium nitrate to form a sol-gel containing hydroxyapatite. A film of the sol gel is applied to at least one side of the substrate and the film coated on the substrate is sintered to form a solid film of calcium phosphate entities. The improvement in the process comprising sintering the film at temperatures selected from a range of temperatures which optimize a composition of calcium phosphate entities in the film. The sintering step converts hydroxyapatite to .alpha.-tricalcium phosphate where extent of such conversion is temperature dependent. The optimized composition comprises a ratio of hydroxyapatite to .alpha.-tricalcium phosphate in the range of 50:50 to 20:80. A sintering temperature is selected to provide these ratios. The sintering temperature is selected from a range of 920.

Abstract: An implant and a process for treating the same wherein the implant has a highly pure coating of crystalline hydroxylapatite (HA). The implant is initially coated with HA using a plasma spraying technique and is then subjected to a two stage process, including a hydrothermal treatment stage and a leaching stage. The resulting implant is highly crystalline, containing only a small percentage of amorphous calcium phosphate and essentially being free of calcium hydroxide, calcium oxide, and calcium carbonate.

Abstract: A method of crosslinking a silazane polymer having Si--H bonds in which the polymer is mixed with a crosslinker selected from alkenyl functional cyclosiloxanes and alkenyl functional cyclosilazanes and a crosslinking promoter and then heated to a temperature sufficient to crosslink the silazane polymer. The mixture of the silazane polymer, crosslinker and promoter is useful in the formation of ceramic matrix composites.

Abstract: Fiber reinforced ceramic matrix composites are prepared by coating refractory fibers having a interfacial coating thereon with a curable preceramic polymer having a char which contains greater than about 50% sealant oxide atoms followed by forming the coated fibers into the desired shape, curing the coated fibers to form a pre-preg, heating the pre-preg to form a composite and heating the composite in an oxidizing environment to form an in situ sealant oxide coating on the composite. The resultant composites have good oxidation resistance at high temperature as well as good strength and toughness.

Abstract: A method for strengthening and increasing the thickness of the strengthened surface layer of a dental ceramic restorative material where the ceramic material is heat treated with a salt composition containing a lithium ion and a metal ion larger than the lithium ion first at a temperature above the strain temperature followed by a second heat treatment with the salt composition at a temperature below the strain temperature. The treatment is especially effective for all-ceramic, high-leucite feldspathic porcelain restorations.

Abstract: The present invention aims at preventing or reducing the lowering in mechanical characteristics of a carbon fiber reinforced carbon composite due to stress orientation caused by the use of a thermosetting resin as a carbon matrix precursor resin to thereby obtain a carbon fiber reinforced carbon composite improved in mechanical characteristics, and for attaining this aim, provides a process for the preparation of a carbon fiber reinforced carbon composite which comprises impregnating a carbon fiber with a bismaleimide-triazine copolymer resin instead of the sizing agent and thermoplastic resin which have been used conventionally and heating the resulting impregnated carbon fiber in a non-oxidizing atmosphere to carbonize or graphitize the resin.

Abstract: Composites in the form of a three-dimensional framework or skeleton of ceic particles are formed by a low cost, low temperature sintering process which decomposes a pre-ceramic inorganic or organic precursor. Upon heating, preferably in air, the precursor decomposes to form a ceramic phase in the form of necks between the individual ceramic particles. The properties of the resulting porous ceramic bodies can be modified, such as toughened by impregnation with monomers, oligomers or polymers which are polymerized or cured in situ. Such composites find use as cosmetic products or protheses for humans and animals, such as dental restoratives and bone implants. Methods of fabrication are disclosed which include the use of a pre-ceramic polymer as a binder for the ceramic particles which forms the necks of material between the individual ceramic particles upon firing.

Abstract: An improved coated orthopaedic implant component is disclosed. The implant may be coated with platinum for improved characteristics. Ion beam coating orthopaedic parts by ion implanting the parts with zirconium ions while the parts are immersed in an oxygen-containing background gas is also disclosed. The adhesion of the graded interface zirconium oxide surface layer so formed is further improved by the initial removal of surface contamination using an ion bombardment and the deposition of an intermediate layer of platinum or silicon between the orthopaedic metal component and the zirconium oxide. Furnace heating results in atomic interdiffusion to enhance adhesion between the surfaces. The zirconium oxide provides a low friction, low wear articulating surface. The graded interface may be characterized by a blackish color and a transition between pure zirconium oxide and pure intermediate layer that extends over a thickness of hundreds of Angstroms.

Abstract: A method for forming a layer of particles on a substrate, such as a layer of phosphor particles on the inside of a CRT, is described. The depends on the use of a double-sided adhesive tape comprising a laminate of a dry adhesive between two protective layers. One of the protective layers is stripped away to expose one surface of the dry adhesive layer which is then pressed up against the substrate surface using a method such as rolling or autoclaving to bring about bubble-free adhesion. The other protective layer is then stripped away, thereby exposing the other surface of the adhesive layer. The particles that will comprise the final layer are then applied to the exposed adhesive surface by means of dusting. This is followed by the removal of any weakly adhering particles from the final particle layer. Finally, the dry adhesive layer is itself removed by means of a heat treatment, leaving in place a uniform layer of particles adhering to the substrate surface.

Abstract: A solid substrate, the surface of which has been modified to introduce reactive groups of a hydrophilic nature thereon, the modification being provided by a primer comprising a first polysaccharide containing as reactive groups amino and hydroxyl groups; and a process for the preparation of such solid substrate.

Abstract: The invention provides (i) a process for preparing tetracalcium phosphate particles, the process comprising the steps of (1) sintering or fusing a powder mixture at a temperature of not lower than 1,400.degree. C., the mixture comprising a powder of calcium source and a powder of phosphorus source in a Ca/P molar ratio of 2/1, and about 0.005 to about 5 parts of an aluminum compound, calculated as Al.sub.2 O.sub.

Abstract: The production of SiC whiskers and of mats thereof on a substrate by treatment, at 1250.degree. to 1500.degree. C., of a gaseous mixture including hydrogen and sources of Si and C atoms which are in the form of at least one oxygen-free compound, in the presence of a metal type catalyst, by a semi-continuous or periodic process, is characterized in that, during the growth period, an Al-Fe catalyst is introduced into the gas phase in the reaction zone, by means of carbon reduction of aluminosilicate ceramics, which comprise at least 73 weight % of Al.sub.2 O.sub.3 and 0.3 to 3.0 weight % of iron oxides and the substrate is a carbonized rayon fiber based carbon fabric which has been pre-treated, prior to carbonization, with a solution of borax and a solution of diammonium phosphate until the quantities of boron and phosphorus in the fabric do not amount to more than 4 and 2 weight %, respectively.

Abstract: There is disclosed a process for encapsulating a preform of arbitrary size and shape for the purpose of manufacturing a body by means of hot isostatic pressing. The preform is encapsulated with glass using a sol gel technique. The glass initially forms a hard, porous layer. Heating the glass in the hot isostatic press results in the formation of a gas-impermeable capsule around the preform.

Abstract: A process for manufacturing carbonaceous parts including the steps of shaping a mixture of carbonaceous powder and bonding agent to form raw parts, cooling the raw parts to ambient temperature at a known rate and firing the cooled parts in a furnace from ambient temperature to a final firing temperature to release volatile particles to produce fired parts devoid of volatile products. This process is improved by placing the raw parts in an electric furnace in the absence of heating filler, heating the raw parts in the furnace to an intermediate temperature of about 200.degree. C. at a fixed initial heating rate such that the loss of volatile products is less than 10% by weight of the total amount of volatile products contained in the raw parts and being a function of the cooling rate such that the internal strain from the shaping and cooling step is freed.

Abstract: A method for forming a ceramic fabric by removing a carbon substrate from a fibrous preform by oxidation. Ceramic coated carbon fibers are laid-up in layers to form a preform. The layers generally have dimensions of from several inches to a few feet depending on the size of the preform. The carbon is exposed at any place where the fiber "ends" have been made by cutting the preform. The carbon core can be easily and economically oxidized at this point, leaving the ceramic coating as the ceramic fabric.

Abstract: The surface of a device that is surgically implantable in living bone is prepared. The device is made of titanium with a native oxide layer on the surface. The method of preparation comprises the steps of removing the native oxide layer from the surface of the device and performing further treatment of the surface substantially in the absence of unreacted oxygen.

Abstract: A method for manufacturing a screen having high luminance is provided including the steps of forming a phosphor layer on a black matrix adhered to a panel, forming a filming layer by coating and drying a filming composition containing a decomposable organic polymer and a reducing agent on the phosphor layer, forming a metal layer on the filming layer, and heating the phosphor layer, filming layer and metal layer to a temperature sufficient to decompose the filming layer.

Abstract: A method of repairing damage to an oxidation-resistant layer on a carbon-carbon composite wherein a composition consisting essentially of a polymeric thermosetting polysilazane and a ceramic powder is applied to the damaged area, cured, and fired.

Abstract: A process is described for providing a conductive metal circuit using a coherent radiation source. The circuit pattern is directly written onto a laser addressable element having a supercooling material layer. A conductive metal toner is then applied to the light struck areas and fired in a furnace to provide a conductive metal circuit.

Abstract: A process for preparing coating compositions of a commingled hydrogel of a polyurethane-polyurea polymer hydrogel and at least one other polymer hydrogel of a polymer different from polyurethane-polyurea; a process for making materials composed of a polymeric plastic or rubber substrate or a metallic substrate, with a coating of the commingled hydrogel thereon; and a process for making medical devices with a coating of the commingled hydrogel thereon, are disclosed. The coating compositions tenaciously adhere to the substrate materials and medical devices to which they are applied due to bonding of a tie coat to a reactive substrate surface and due to the commingling of the two hydrogel components. The coating compositions and coated materials and medical devices are non-toxic and biocompatible, making them ideally suited for use in applications such as for catheters, catheter balloons and stents.

Abstract: A method of manufacturing artificial tooth veneer restorations for natural teeth composed of a ceramic core by pressing and sintering ceramic powder. The core is preferably manufactured from a high strength densely sintered ceramic material by copy milling from an impression of the prepared tooth surface to a compacted body, a presintered body or a sintered body. Alternatively, the core is manufactured by compacting the ceramic powder against a body, which surface is copy milled from a model of the prepared tooth surface. During the copy milling, the sintering shrinkage is considered by enlargement of that body. The tooth veneer restorations are given their final shape by shaping the external surface of the compacted, presintered or sintered ceramic body. After the final sintering, the external surface can be shaped before a veneer material is attached to the external surface of the core by firing of dental porcelain.

Abstract: In order to produce lightweight mirror structures or other reflecting components, preformed silicon elements of sufficient wall thickness are applied to a CFC or CMC substrate structure with the dimensions of the component to be produced, at a temperature in the range 1300.degree. C. and 1600.degree. C. either in vacuum or in a protective atmosphere. In this way a mirror structure or reflector is formed directly. It is possible to work at temperatures in the range of 300.degree. C. to 600.degree. C. when the silicon is applied in the form of a preform such as a wafer, which is joined to the substrate by way of a zone of a melt eutectic incorporating a nonferrous metal, which is preferably gold. The surfaces are subsequently coated.

Abstract: A method of effecting the coloration of a restoration to be mounted on a tooth including the steps of forming a mixture of powdered dental porcelain and a photonucleable silicate glass and shaping the mixture into a dental restoration. The dental restoration is heated in an oven to its fusing temperature and allowed to cool. Selected areas of the restoration are exposed to ultra-violet light. The dental restoration is reexposed to high energy while the color of the selected areas changes.

Abstract: A method for producing thick ceramic films of greater than 10 .mu.m on selected substrates is described. Conventional sol gel solutions are loaded with up to about 90% by weight of finely divided ceramic particles and mixed. The resulting slurry or paint can be either spun or dip coated or sprayed or painted onto a planar or other substrate, fired to remove the organic materials and to develop a microcrystalline structure. The fired film may then be heated. Composite films are also contemplated.