Abstract: A drug delivery ophthalmic insert prepared by forming a water soluble solid polymer into a paste by the addition of a small fixed amount of water, drying the paste and then sectioning the paste into a plurality of rod shaped inserts is provided. The insert is rendered suitable for prolonged and sustained delivery of medication to the eye since it is formed by the addition of a small amount of water and has a surface area less than about 3 mm.sup.2. Specific water soluble solid polymers which may be used include methylcellulose, hydroxyethyl cellulose, alginic acid and combinations thereof as well as mixtures of pilocarpine dispersed in methylcellulose and its combinations.

Abstract: A plurality of binary diffractive optic lenses are formed in the surface of one substrate and a corresponding plurality of recesses are formed in the surface of another substrate. The binary diffractive optic lenses on one substrate are aligned with the recesses on the other substrate and the two substrates are bonded together. A plurality of individual binary diffractive optic lens cover assemblies are obtained by dicing the two bonded substrates.

Abstract: A human detention appliance or pacifier device or anti-thumb sucking device is made by a method of injection molding whereby a charge of fluoridating material is admixed with a high-temperature solvent, and then tumbled with a base thermoplastic molding material to form a pre-fluoridated mixture stable which is stable within the temperatures necessary to melt the mixture and the high-temperature limit of the high-temperature solvent, and physically embodied in the molding so that when used, the fluoridating material will leach out of the appliance and become mixed with fluids in the mouth at the buccal, labial, lingual and occlusal surfaces of the teeth which come in contact with the appliance.

Abstract: A method of producing an article of ceramic material for replacement of a lost substance or tissue in the human body includes making a model having a contour of the article to be produced and positioning in a copying machine the model and a blank from which a tool is to be made. The contour of the model is sensed by sensing devices and transmitted to the blank. The model contour is linearly enlarged by use of mechanical procedures so as to define a linearly enlarged contour on the blank. After the enlarged contour has been defined on the blank, a tool is formed from the blank which has a contour corresponding to the linearly enlarged contour. The ceramic starting material is applied and compacted over the contour of the tool to produce an article with a corresponding enlarged contour.

Abstract: A method of making a mold for use in the manufacturing of appliances for use in filling endodontically prepared root canals including the steps of drilling spaced apart holes into a flat base member, inserting into each of the holes elongated metal patterns having the desired configuration of a filler covered carrier shaft portion of an endodontic appliance, forming a vessel with the base member as the bottom and the patterns extending upwardly therein, pouring liquid plastic and a catalyst into the vessel and allowing it to solidify to form a mold, and removing the mold from the vessel and from the base, the mold having a cavity therein for each of the patterns, each cavity being useful for forming an appliance for use in filling an endodontically prepared root canal.

Abstract: The present invention is directed to a process for manufacturing a cladded optical fiber. The cladding and core are halide materials. An interface for inhibiting radiation scatter is provided at the boundary between the halide cladding and the halide core. The process steps include extruding a first halide or halide core from a first chamber, and extruding a second halide or halide cladding from a second chamber into contact with the halide core. The halide cladding is joined to the halide core at the boundary.

Abstract: A method of reinforcing a dental appliance or prosthesis comprising a resin, which includes the steps of applying to a resin portion of the dental appliance or prosthesis a lightweight, woven aramid or extended chain polyethylene fabric, and covering the fabric with more of the resin. Also disclosed are reinforcing materials (preferably a plasma-coated Spectra.TM. fabric), and dental appliances or prostheses reinforced by a lightweight, woven aramid or extended chain polyethylene fabric.

Abstract: A roll-stamper for forming substrates of an information-recording medium includes at least one stamper being fastened along a peripheral face of a mirror roller, carrying on a surface thereof patterns each corresponding to a preformat for an information recording medium, also having stoppers fixed along both edges on the reverse side thereof, and being fastened to the mirror roller by inserting the stoppers respectively into negative stopping-grooves cut into the mirror roller in parallel with the axis of the mirror roller.

Abstract: A root canal sealer and cleaner provided with a dimension discriminating part at their heads so as to discriminate the dimension easily, and a method and device for forming the dimension discriminating part on the root canal sealer and cleaner.According to the root canal sealer and cleaner of the invention, a coloring part having a hue for indicating the required dimension is formed directly at the head gripped by an operating tool such as pincers, etc., at the time of the root canal cleaning and sealing treatment of a tooth, so that it is possible to indicate the dimension by each root canal sealer and cleaner itself, to discriminate easily and exactly the dimension of each root canal sealer and cleaner, and to distinguish it from those of different standards even when it is mixed with them in the course of operation.

Abstract: A process for producing an optical recording medium, including the steps of: melt-extruding a resin to form a resin sheet; passing the resin sheet under pressure between a first roller having a predetermined unevenness pattern and a second roller disposed opposite thereto before the resin sheet is hardened, thereby to transfer the unevenness pattern to a surface of the resin sheet; and forming a recording layer having an organic coloring matter on the surface of the resin sheet provided with the unevenness pattern; wherein the steps are conducted while the resin sheet is moved.

Abstract: The invention relates to a process for the treatment of dental impressions of conventional molding material, in which the surface of the impressions is treated prior to filling with plaster with an aqueous solution which contains 0.01 to 10 % by weight of a fluorine compound. The detrimental effect which the surface-active substances adhering to the dental impressions have on the surface finish of the plaster models which are produced using the dental impressions is thus eliminated.

Abstract: A transmissive screen for use in a video projector or the like and a manufacturing method thereof is provided wherein a UV-curable resin is coated on a back film or a mold. One surface of a lens surface of opposite shape is formed by the mold. The UV-curable resin is sandwiched between the back film and the mold, ultraviolet rays are irradiated on the UV-curable resin and the screen is released from the mold, thereby forming a transmissive screen in which the lens surface is formed on one surface by the UV-curable resin and the back film is formed on the other surface. Thus, the screen can be reduced in weight and thickness, and can be mass-produced.

Abstract: A method is disclosed for preparing an improved bioreactive material of the glass or partially crystallized glass type for bone prostheses or dental implants, which can be welded to bone tissue by chemical bonding. The material consisting essentially of, by weight, 5 to 14% Na.sub.2 O, 0 to 12% P.sub.2 O.sub.5, 49 to 57% SiO.sub.2, and balance, no more than 33% CaO+CaF.sub.2, the material containing 0.5 to 7% CaF.sub.2, and is prepared by a method comprising the steps of preparing a mixture of powders constituting a precursor of the material made of carbonates, phosphates, silica, oxides and fluorides, melting, homogenizing, casting and cooling the mixture to obtain an intermediate, non-crystallized glass, optionally annealing, and then grinding, either pressing the non-crystallized ground glass obtained cold to shape it, then sintering naturally or under a load after degassing, or sintering under a load directly after degassing, then cooling and optionally polishing or machining.

Abstract: A method and system for replicating microstructures surface relief patterns, such as diffraction patterns including holograms, by casting. A liquid casting resin is held between a surface relief master of the microstructure to be replicated and a substrate while the resin is hardened by actinic radiation curing. Application of resin to edges and discontinuities of the master is avoided in order to reduce undesirable build-up of resin on these areas of the master. The hardened resin surface relief replica may optionally be coated with a discontinuous graphical pattern of a clear or colored paint that eliminates the effect of the surface relief pattern in the regions so coated.

Abstract: A plastic optical fiber comprising a core polymer having a refractive index of n.sub.1, which comprises a polymer of .alpha., .beta.-unsaturated carboxylic acid fluoroalkylester represented by the general formula [I] as the main monomer, and a clad copolymer having a refractive index of n.sub.2, which comprises perfluoro(2,2-dimethyl-1,3-dioxole) as the main monomer, and which satisfies the relationship of (n.sub.1 -n.sub.2 .gtoreq.0.01): ##STR1## wherein X represents CH.sub.3, H, D, F, Cl, or CF.sub.3, Y represents H or D, and Rf represents a fluoroalkyl group having a linear or branched chain. The optical fiber is prepared by a melt-extrusion method. The optical fiber has excellent light transmitting properties, and it is suitable as an optical fiber for long distance light communication.

Abstract: Dental light-curing resins are cured with light and under pressure by placing the uncured resin on a cast or mold or dental appliance to be prepared then covered with a transparent or translucent flexible membrane or sheet. In a chamber gas pressure is applied to the sheet and, in turn, to all parts of the underlying resin and, while pressurized, the resin is exposed to light to cure it.

Abstract: A method of manufacturing appliances for use in filling endodontically prepared root canals including the steps of forming a mold having a plurality of spaced apart elongated cavities therein, filling each of the cavities with uncured endodontic filler material, inserting into each cavity the shaft portion of a filler carrier, each filler carrier having a handle portion that remains exterior of the mold, placing the mold with the uncured filler material and filler carrier therein in an oven, heating the mold with the uncured filler material and filler carriers therein to cause the filler material to cure and adhere to the filler carrier shaft portions, and removing the filler carriers having the filler material cured thereon, each of which is ready for use as an appliance to fill an endodontically prepared root canal.

Abstract: A method of making a positive model of a tooth or gum involving the steps of pouring hardenable positive impression material into a negative impression of the tooth or gum comprising a curved, vinyl polysiloxane composition, and hardening the positive impression material, wherein the improvement involves applying finely divided palladium over at least part of the surface of the negative impression that will contact the positive impression material before pouring the hardenable positive impression material.

Abstract: The fragranced orthodontic appliance and method of making the same utilizes a fragranced "cold cure" acrylic. The method comprises the steps of combining fragrancing oils in a predetermined ratio with a monomer liquid. The monomer is then combined in a conventional manner with a polymer to form a hard acrylic orthodontic appliance. The appliance includes a hard cold cure acrylic base member which is formed from a suitable powdered polymeric component and a liquid monomeric component, the liquid monomeric component containing a selected fragrancing oil therein. The method comprises the steps of admixing an effective amount of fragrancing oil with a liquid monomeric component and then admixing the resulting mixture with an effective amount of a powdered polymeric component to form an acrylic base member. Hardware is then embedded in the acrylic base member.

Abstract: The invention relates to a method of producing an optical cable in which at least one optical waveguide fed forward from a supply reel is provided with a loosely surrounding jacket by means of extrusion, whose length is subsequently reduced relative to the length of the optical waveguide travelling through the expander and is thereafter wound-up. The excessive length of the optical waveguide is consequently distributed uniformly along the overall length of the optical cable, because of the fact that the optical waveguides paid-out from the supply reel are stranded before they are fed into the extruder.

Abstract: A method for making a dental root canal filling point wherein provision is made of a rotary member having its outer processing surface in the form of a curved plane in parallel with its axial direction and adapted to be rotated at a predetermined speed, and a moving member in which at least its processing surface is located in parallel with the processing surface of the rotary member and adapted to move at a speed substantially identical with a peripheral speed of the rotary member in an opposite rotational direction as the rotational direction of the rotary member in a gap portion in which a minimum distance is defined between the processing surfaces of the rotary member and the moving member.

Abstract: The present invention is an improvement upon a known apparatus for polymerization of a body from dental plastic material by irradiation of the body with radiation of a selected wave length in the range between about 350 nm and about 550 nm. To achieve a desired degree of polymerziation of the dental plastic, a specific amount of radiation must be applied to the body. In order to achieve reproducible irradiation results in spite of fluctuations in supply voltage, alterations in lamp characteristics, burn out of one or more lamps, shifting of spectral outputs, replacement of defective or superannuated lamps, soiling of lamps and reflector surfaces and/or changes of operating temperatures in the irradiation area, a supplemental detection system in provided.

Abstract: A multifilament type plastic optical fiber having a substantially rectangular cross-section and an islands-in-the-sea structure in which 100 to 10,000 islands are arranged in the sea, wherein the respective islands have a substantially circular cross-section and a core-sheath structure, the islands are arranged in a zigzag-stacked structure, the core occupaney ratio in the multifilament type optical fiber cores section is at least 50% and the brightness index value I which is defined by the following (1), is at least 4.5.times.10.sup.-2 : ##EQU1## wherein S stands for the core occupancy ratio in the multifilament type optical fiber, .alpha. stands for the transmission loss (dB/m) per meter of the multifilament type optical fiber, NA stands for the numeral apertures, and L stands for the length (m) of the used optical fiber.

Abstract: A human detention appliance or pacifier device or anti-thumb sucking device is made by a method of injection molding whereby a charge of fluoridating material is admixed with the base thermoplatic molding material to form a pre-fluoridated mixture stable within the temperatures necessary to melt the mixture and physically embodies in the molding so that when used, the fluoridating material will leach out of the appliance and become mixed with fluids in the mouth at the buccal, labial, lingual and occlusal surfaces of the teeth which come in contact with the appliance.

Abstract: An orthodontic appliance for maloccluded teeth and an associated method of construction utilizes an elastomer base material comprised of a silicone elastomer composition. The elastomer composition, when in an uncured condition, possessses a sufficiently low viscosity so that the positioner can be formed in a low pressure injection molding process and which, when in a cured condition, possessses a relatively high resistance to tear.

Abstract: A glazing device, and a method for using such device to apply a surface glaze to a dental construct. The device includes glazing material associated with a shrinkable, hollow carrier. The method includes associating glazing material with a hollow carrier composed of a shrinkable and removable material, assembling the construct and carrier with the construct positioned within the carrier, shrinking the carrier onto the construct, removing the carrier, and maturing the material to a glaze. The device and method find particular application in applying coloration, either uniformly or in a pattern, to a dental construct.

Abstract: An optically clear custom tooth positioning and retaining appliance made in a flask or mold device having mold members from an elastomeric or resilient thermoplastic material with the capability of having optically clear transparentness. After the appliance has been trimmed and/or buff polished subsequent to molding thereof which causes the appliance to have a frosty or translucent appearance, the exterior surfaces of the appliance has been subjected to a source of concentrated heat to cause surface melting which produces transparentness, cooling the appliance before, during and after heating as needed to preserve its integrity, and optionally utilizing the mold members from the flask or reproductions thereof in the archways of the appliance during heating thereof.

Abstract: A method of applying a surface glaze to a dental construct. The method includes associating glazing material with a carrier composed of a highly flexible and removable material, assembling the construct and carrier with the construct positioned within the carrier, forcing the carrier onto the construct by differential fluid pressure, removing the carrier, and maturing the glazing material to a glaze. The method finds particular application in applying coloration, either uniformly or in a pattern, to a dental construct.

Abstract: A method of obtaining hydrocolloid impression material to be used in conjunction with making dental impressions where a quantity of the hydrocolloid impression material in solid form is cut into a mass of small parts. This mass of small parts is then heated within a microwave oven until the mass is liquefied and achieves a homogeneous consistency. The liquid mass is then poured into a tray and tempered and then utilized to make a desired dental impression.

Abstract: A process for coating the pores of a mineral matrix with collagen by pumping collagen through the molded matrix is disclosed. The resulting coated matrix can be used as a prosthesis in bone repair.

Abstract: A method of making a dental appliance made of an elasticized acrylic containing embedded nylon fibers including the steps of heating the thermoplastic material, forming it onto a dental cast, and cooling it to a rigid state. The fibers may be arranged in various patterns within the elasticized acrylic and it is the fibers which act on the arch through the elasticized acrylic. The appliance may be used as a tooth positioner, a retainer, a splint, or a base plate.

Abstract: A preformed pattern for forming an occlusal splint having a U-shaped member composed of material that is form-stable at room temperature and sufficiently pliable at an elevated temperature to be conformed to the bits of a person's jaw or to a model of such person's jaw.

Abstract: The present invention relates to the addition of aluminum salts of fatty acids with 12 to 18 carbon atoms, particularly aluminum stearate, to dental impression materials on the basis of addition and/or condensation crosslinking organosilicones to improve their structural viscosity behavior and thus to ease their handling for the dentist.

Abstract: A method of making a positive model of a tooth or gum including the steps of pouring hardenable positive impression material into a negative impression of the tooth or gum comprising a cured, vinyl polysiloxane composition, and hardening the positive impression material, and further including applying finely divided palladium over at least part of the surface of the negative impression that will contact the positive impression material before pouring the hardenable positive impression material.

Abstract: Disclosed herein are a novel and highly refractive S-alkyl thiocarbamate base resin useful in preparing lenses and a process for producing the resin comprising reacting one or more of polyisocyanate compounds and one or more of mercapto compound having at least one hydroxyl group, a plastic lens made of the resin, and a process for making a plastic lens of high profile regularity from the resin by using internal mold releasing agents in the casting polymerization process.

Abstract: For use in making dental restorations, a model is prepared by taking an intra-oral impression and molding in the impression a replica model made from the thermosetting resin and a thermoplastic resin. The thermosetting resin provides a tough, heat- and abrasion-resistant surface. Heat from the molten thermoplastic resin accelerates the curing of the thermosetting resin.

Abstract: Disclosed are ceramic compositions which have been improved through the addition of a light-curing resin. Porcelain compositions are formulated to include a light-curing resin, generally of the acrylic monomer type, molded into a desired shape, and subjected to an appropriate light source to preset the molded object, for example, a porcelain inlay or margin. The present ceramic object having a thus improved integrity is transported or further manipulated, and then fired in a conventional porcelain firing oven. Ceramic compositions made in accordance with the present invention may be employed in all types of dental restoration procedures, including the fabrication of margins, inlays, crowns, laminates, as well as various non-dental applications.

Abstract: Control of speed and uniformity of the heating of the working zone of the preform in a glass drawing operation in which the softening heat is applied by forced convection (13), using a separate fluid heating zone to introduce temperature and velocity controlled fluid. The size of the working zone is further controlled by changing (18) the configuration of a movable exit sleeve. Uniformity and accuracy of temperature is enhanced by normalization (10) of the temperature of the preform close to a preselected value before the preform enters the furnace. A glass drawing apparatus embodies the preferred means to carry out the process, providing a two-chamber furnace having an air heating chamber (44) connected by air delivery channels (51) to a drawing chamber (43). The drawing chamber has preform inlet (41) and a drawn product outlet (56). Each of the latter preferably has an adjustable opening diameter. The inlet is provided with a pre-cooling collar (35).

Abstract: Optical fibers formed by rolling crystals of infrared transmissive material, such as potassium chloride, have been made into a smooth optical fiber by rolling between smooth grooved rolls (16) and (20) in a heated, atmosphere controlled environment.The Government of the United States of America has rights in this invention pursuant to Contract Number N00014-79-0-0691 awarded by the Department of Defense.

Abstract: A scratch resistant coating is applied to one or both surfaces of an extruded thermoplastic synthetic resin web by passing the web through a polishing roll stack wherein at least one of the rolls has thereon a film of a material forming such a scratch resistant coating, the coating being in this way transferred from the roll to the surface of the web.

Abstract: A homogeneous porcelain block is used instead of using porcelain powder in a porcelain press technique to make dental prosthesis. Porcelain block is placed directly onto a mold, and softened by heating. Then the upper and the lower flasks of the mold assembly are closed so as to press the porcelain block. The process prevents adverse effects from steam and gases during the procedure. Therefore the porcelain block eliminates discoloration, bubbles, uneven baking and weakness in the porcelain block. In addition, considerable time and labor may be saved.

Abstract: The invention is a method of manufacturing a dental restoration from a polymerizable resin or composite resin with an alloy structure, or a method of manufacturing an alloy substructure-reinforced dental restoration. An alloy structure or substructure is first coated with a liquid, vitrifiable ceramic layer. To ensure against crazing in the ceramic layer upon vitrification, the ceramic and alloy have generally similar coefficients of thermal expansion. After vitrification, the ceramic becomes a ceramic bonding layer. Micropores are then formed on that layer, as by sandblasting or by etching with a suitable etching acid. A silane coupling agent is then applied to the micropore-containing ceramic bonding layer. Finally, the silane coupling agent is overlain with a polymerizable resin or composite resin material, and the resin or composite resin is polymerized.

Abstract: A method of producing dental appliances, especially orthodontic appliances, but also including dentures and other dental prosthesis. The method includes placing a self-merging dental gel especially as a stream on a dental cast and under and around preformed dental parts mounted on the cast and merging the dental gel into a homogeneous form of the complete part and then curing the formed dental appliance. The dental gel is a colloidal system including a hardenable dispersing medium, a colloid and a catalyst, preferably a photoinitiator.

Abstract: A preformed pattern for forming an occlusal splint comprises a U-shaped member composed of material that is form-stable at room temperature and sufficiently pliable at an elevated temperature to be conformed to the bits of a person's jaw or to a model of such person's jaw.

Abstract: An ionogenic compound, soluble or dispersible in aziridine compounds is utilized for delaying the polymerization of aziridine compounds initiated by a sulfonium salt. Said ionogenic compounds contain an anion which is more nucleophilic than the anion present in the sulfonium salt employed. Moreover, a preparation for dental purposes is described which contains these components.

Abstract: The specification discloses a new method and apparatus for treating extruded TEFLON (fluoropolymer) tubing to significantly improve its dimensional and optical characteristics. Diameter tolerance is .+-.0.0002, concentricity rises to 95%, and optical clarity rises to the theoretical transmittance of the material. The tubing is first cleaned, and then heated to a transition temperature above 150.degree. C. to soften and further homogenize the tubing. The tubing is then drawn through a polished diamond die and then rapidly cooled. The cooled tubing may be further stabilized by an annealing step. Both a batch mode and a continuous mode of operation are disclosed.

Abstract: For use in making dental restorations, a model is prepared by taking an intra-oral impression and molding in the impression a replica model made from thermoplastic resin and an optional thermoset resin. The model includes a flexible support adhered to the underside of the model. When the model is flexed or cut, cracks will form through the replica gingival tissue between adjacent replica teeth. The flexible support acts as a hinge to provide access to interproximal spaces between replica teeth. A preferred flexible support is a layer of a tough and flexible second thermoplastic resin.

Abstract: For use in making dental restorations, a model is prepared by taking an intra-oral impression and molding in the impression a replica model made from a thermosetting resin and a thermoplastic resin. The thermosetting resin provides a tough, heat- and abrasion-resistant surface. Heat from the molten thermoplastic resin accelerates the curing of the thermosetting resin.

Abstract: Light-diffusing methacrylic plates are continuously prepared by casting a polymerizable material composed of methyl methacrylate or a partially polymerized product thereof with 0.2 to 3.0% by weight of a light diffusing material between two belts. The belts are separated by an average distance l but are capable of both compression and expansion relative to this average separation. The method involves applying compression at at least one point in the casting space to reduce the separation distance and then allowing expansion back to a maximum distance wherein the maximum spacing between the belts is from (l+1) mm to (l+0.2) mm and the minimum spacing during compression is from (l-1) mm to (l-0.2) mm.

Abstract: A dental impression composition comprising alginate material and biocidal component.A method for reducing microorganism contamination in alginate dental impressions comprising preparing a mixture comprising alginate, water and biocide.