Patents Assigned to Jeneric/Pentron Inc.
  • Patent number: 6872076
    Abstract: A dental restoration comprising a fiber reinforced composite framework and one or more of a randomly dispersed, fiber-filled veneer, a soft particulate filled composite veneer having a strain to failure greater than that of FRC framework and/or a brittle particulate filled composite veneer having a strain to failure value less than that of the FRC framework. The fiber filled veneer is advantageously placed beneath the framework, the soft veneer is advantageously pled where tensile stresses are expected to occur, while the brittle particulate filled veneer is placed where compressive stresses are expected to occur.
    Type: Grant
    Filed: October 25, 2001
    Date of Patent: March 29, 2005
    Assignee: Jeneric/Pentron Inc.
    Inventors: Ajit Karmaker, Arun Prasad, Gregg Daskalon
  • Patent number: 6821462
    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 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 shell can be deposited concurrently slice after slice and sintered/cured simultaneously.
    Type: Grant
    Filed: September 5, 2001
    Date of Patent: November 23, 2004
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Martin L. Schulman, Carlino Panzera
  • Patent number: 6756012
    Abstract: Chromium-cobalt alloys useful for use with high-expansion porcelains in the fabrication of prosthetic dental appliances. The alloys herein comprise cobalt, chromium and manganese as essential components; and include one or more of aluminum, indium, gallium, tin, and germanium; and may include one or more of iron, nickel, palladium and platinum. Optional components include gold, tantalum, niobium, molybdenum, tungsten, vanadium, iridium, ruthenium, rhenium, titanium, silicon, copper, zirconium, hafnium, boron, yttrium, and rare earths metals. The alloys herein are useful with high-expansion dental ceramics and porcelains.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: June 29, 2004
    Assignee: Jeneric/Pentron, Inc.
    Inventor: Arun Prasad
  • Patent number: 6537563
    Abstract: A gel composition for use in etching the surfaces of teeth in preparation for prophylaxis, repair, or restoration, comprising an aqueous solution of an effective quantity of an acid; and a colloidal silica sol, wherein the silica portion of the sol comprises from about 3 to about 20 weight percent of the total etchant composition.
    Type: Grant
    Filed: May 11, 2001
    Date of Patent: March 25, 2003
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Weitao Jia, Shuhua Jin
  • Patent number: 6533969
    Abstract: Process for the manufacture of dental restorations using high strength ceramic components. A wax pattern is built around a high strength ceramic component on a die. The wax pattern with the high strength ceramic component is surrounded with investment material. The wax is burned out, leaving a mold with the high strength ceramic component. The mold is filled with a ceramic material, covering the high strength ceramic component, creating a dental restoration.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: March 18, 2003
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Gregg Daskalon, Dmitri Brodkin, Ajit Karmaker, Elie Zammarieh, Martin L. Schulman, Arun Prasad, Carlino Panzera, Paul Panzera
  • Patent number: 6517623
    Abstract: This invention is directed to lithium disilicate (Li2Si2O5) based glass-ceramics comprising silica, lithium oxide, alumina, potassium oxide and phosphorus pentoxide. The glass-ceramics are useful in the fabrication of single and multi-unit dental restorations (e.g. anterior bridges) made by heat pressing into refractory investment molds produced using lost wax techniques. The glass-ceramics have good pressability, i.e., the ability to be formed into dental articles by heat-pressing using commercially available equipment. In accordance with one embodiment directed to the process of making the glass-ceramics, the compositions herein are melted at about 1200° to about 1600° C., thereafter quenched (e.g., water quenched or roller quenched) or cast into steel molds, or alternately, cooled to the crystallization temperature. The resulting glass is heat-treated to form a glass-ceramic via a one or two step heat-treatment cycle preferably in the temperature range of about 400° to about 1100° C.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: February 11, 2003
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Dmitri Brodkin, Carlino Panzera, Paul Panzera
  • Patent number: 6484791
    Abstract: A disposable plunger for use in a pressing furnace for the fabrication of dental restorations. The plunger is fabricated of a partially sintered ceramic material. The plunger is fabricated by known casting methods. The mold used for making the plunger can be supplied by a manufacturer of molds or can be easily made by using an alumina or similar plunger as a model. Laborious cleaning and grinding are not required with plungers herein described. Cracking problems that occur with prior art plungers are decreased, if not completely eliminated.
    Type: Grant
    Filed: December 21, 1999
    Date of Patent: November 26, 2002
    Assignee: Jeneric/Pentron, Inc.
    Inventor: Patricia E. Vidal
  • Patent number: 6455451
    Abstract: This invention is directed to lithium disilicate (Li2Si2O5) based glass-ceramics comprising silica, lithium oxide, alumina, potassium oxide and phosphorus pentoxide. The glass-ceramics are useful in the fabrication of single and multi-unit dental restorations (e.g. anterior bridges) made by heat pressing into refractory investment molds produced using lost wax techniques. The glass-ceramics have good pressability, i.e., the ability to be formed into dental articles by heat-pressing using commercially available equipment. In accordance with one embodiment directed to the process of making the glass-ceramics, the compositions herein are melted at about 1200° to about 1600° C., thereafter quenched (e.g., water quenched or roller quenched) or cast into steel molds, or alternately, cooled to the crystallization temperature. The resulting glass is heat-treated to form a glass-ceramic via a one or two step heat-treatment cycle preferably in the temperature range of about 400° to about 1100° C.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: September 24, 2002
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Dmitri Brodkin, Carlino Panzera, Paul Panzera
  • Patent number: 6447297
    Abstract: An endodontic post comprising a combined endodontic post and filling material tip in a single unit. To use the post unit, the device is placed in an oven or heater to heat and soften the thermoplastic material. The device will then be placed in a root canal that has been opened to a predetermined dimension by use of endodontic files, to seal the apical end. If necessary, the gutta percha can be compacted toward the apex, while it is still in the softened state, to ensure the apex is adequately sealed. The post is then cemented into place by lining the canal walls with a bonding agent and filling the interface between the post and the walls of the canal with a dual cure resin cement. This will result in a coronal seal of the canal via resin restorative material and an apical seal of the canal by means of gutta percha and sealant. The remaining portion of the post, extending supra-gingivally, will be used to build a core around it. Any excess will be cut off.
    Type: Grant
    Filed: May 12, 2000
    Date of Patent: September 10, 2002
    Assignees: Jeneric/Pentron, Inc.
    Inventors: Larry A. Lopez, Bruce A. Finnigan, Ajit Karmaker
  • Patent number: 6441346
    Abstract: A burn-out furnace having heating system configured in a series or plurality of radiating sleeves aligned on top of one another against at least one wall of the burn-out furnace. At least one heating element is disposed in the radiating sleeves. The heating element is preferably a single piece of wire which is coiled or wound along its entire length and curved after it exits each radiating sleeve to continue into the next tube, and “zig-zag” through the plurality of tubes. The heating element is stretched to a point whereby during operation of the furnace, when the heating element is heated, there is little or no creeping of the wire occurring. Moreover, the heating element contains very tight turns between the sleeves as the direction of the element reverses and it continues the zig-zag configuration through the plurality of radiating sleeves.
    Type: Grant
    Filed: September 4, 2001
    Date of Patent: August 27, 2002
    Assignee: Jeneric/Pentron, Inc.
    Inventor: George Zychek
  • Patent number: 6428319
    Abstract: An endodontic post comprising a combined endodontic post and filling material tip in a single unit. To use the post unit, the device is placed in an oven or heater to heat and soften the thermoplastic material. The device will then be placed in a root canal that has been opened to a predetermined dimension by use of endodontic files, to seal the apical end. If necessary, the gutta percha can be compacted toward the apex, while it is still in the softened state, to ensure the apex is adequately sealed. The post is then cemented into place by lining the canal walls with a bonding agent and filling the interface between the post and the walls of the canal with a dual cure resin cement. This will result in a coronal seal of the canal via resin restorative material and an apical seal of the canal by means of gutta percha and sealant. The remaining portion of the post, extending supra-gingivally, will be used to build a core around it. Any excess will be cut off.
    Type: Grant
    Filed: October 6, 2000
    Date of Patent: August 6, 2002
    Assignees: Jeneric/Pentron, Inc.
    Inventors: Larry A. Lopez, Bruce A. Finnigan, Ajit Karmaker
  • Patent number: 6428614
    Abstract: Opaque porcelains for use with metal cores in the manufacture of PFM restorations. The porcelains exhibit a coefficient of thermal expansion (CTE) substantially equal to or slightly above the CTE of the metal to which it is applied. The porcelains exhibit a CTE equal to or up to about 1.5×10−6/° C. higher than the dental alloys to which they are applied as the opaque. The porcelains are fabricated from a mixture of two frit compositions. A high expansion, leucite containing frit is combined with a low melting glass frit to provide a porcelain having an expansion in the range of 16.9 to about 18×10−6/° C. in the temperature range of 25°-500° C.
    Type: Grant
    Filed: June 29, 2000
    Date of Patent: August 6, 2002
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Dmitri Brodkin, Carlino Panzera, Paul Panzera
  • Patent number: 6413660
    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.
    Type: Grant
    Filed: June 11, 1999
    Date of Patent: July 2, 2002
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Gregg Daskalon, Ajit Karmaker, Elie Zammarieh, Martin L. Schulman, Arun Prasad, Carlino Panzera, Dmitri Brodkin, Paul Panzera
  • Patent number: 6375729
    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.
    Type: Grant
    Filed: March 17, 2000
    Date of Patent: April 23, 2002
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Dmitri Brodkin, Carlino Panzera, Paul Panzera
  • Patent number: 6354836
    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).
    Type: Grant
    Filed: August 18, 1999
    Date of Patent: March 12, 2002
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Carlino Panzera, Dmitri Brodkin, Paul Panzera
  • Patent number: 6345984
    Abstract: Ready-to-use preshaped, prefabricated cured structural components are prepared in a variety of shapes and sizes to be used in the fabrication of dental appliances. Preferably the structural components are fabricated of a fiber-reinforced composite material or a particulate-filled composite material comprising fibers or particulate filler impregnated with a polymeric matrix. The polymeric matrix is partially or fully cured to the point of sufficient hardness to provide a ready-to-use structural component for use in the fabrication of dental appliances such as orthodontic retainers, bridges, space maintainers, tooth replacement appliances, splints, crowns, partial crowns, dentures, posts, teeth, jackets, inlays, onlays, facings, veneers, facets, implants, abutments, cylinders, and connectors.
    Type: Grant
    Filed: June 25, 1999
    Date of Patent: February 12, 2002
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Ajit Karmaker, Martin L. Schulman, Arun Prasad
  • Patent number: 6325839
    Abstract: Metal materials are sintered using microwave energy to provide high strength dental restorations. The metal materials used to manufacture the dental restorations herein are sintered to high density to provide high strength products that have a density close to the density achieved when the same materials are cast. A dense solid having a fine microstructure is achieved using microwave heating. Through the process described herein, higher heating rates may be achieved, reducing the time necessary for sintering the materials. The process is faster than conventional processes used in the manufacture of dental restorations, eliminates time-consuming steps typically involved in the lost wax process and provides materials with better grain-size control and properties. It is possible to produce high strength dental restorations at lower temperatures having high hardness and density and small grain size.
    Type: Grant
    Filed: July 20, 2000
    Date of Patent: December 4, 2001
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Arun Prasad, Gordon S. Cohen
  • Patent number: 6322728
    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.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: November 27, 2001
    Assignee: Jeneric/Pentron, Inc.
    Inventors: Dmitri Brodkin, Carlino Panzera, Paul Panzera
  • Patent number: 6302186
    Abstract: A disposable plunger for use in a pressing furnace for the fabrication of dental restorations. The plunger is fabricated of a refractory investment material such as gypsum-bonded, phosphate-bonded or ethyl silicate-bonded investment materials. The plunger is fabricated by known casting methods. The mold used for making the plunger can be supplied by a manufacturer of molds or can be easily made by using an alumina or similar plunger as a model. Laborious cleaning and grinding are not required with plungers herein described. Cracking problems that occur with prior art plungers are decreased, if not completely eliminated.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: October 16, 2001
    Assignee: Jeneric/Pentron, Inc.
    Inventor: Patricia E. Vidal
  • Patent number: 6270562
    Abstract: A filler material comprising a fibrous material and one or more forms of surface-modifying particles for use in dental composites and dental restorations. The surface-modifying particles are bonded to the fibrous material to increase the surface area of the fibrous material and improve the bonding properties of the fibrous material to enable it to better bond to a resin matrix material in a dental composite. In accordance with the present invention, the fibrous material possesses a lower melting temperature than the surface-modifying particles. The surface-modifying particles and the fibrous material are heated to a temperature below the softening temperature of the fibrous material but at a temperature and time sufficient to soften the surface of the fibrous material in order to bond the surface-modifying particles thereto.
    Type: Grant
    Filed: June 10, 1999
    Date of Patent: August 7, 2001
    Assignee: Jeneric/Pentron, Inc.
    Inventor: Weitao Jia