Patents Assigned to Pentron Corporation
  • Patent number: 6846181
    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: October 26, 2001
    Date of Patent: January 25, 2005
    Assignee: Pentron Corporation
    Inventors: Ajit Karmaker, Martin L. Schulman, Arun Prasad
  • Patent number: 6787584
    Abstract: Curable compositions comprising degradable macromonomers having one or more terminal acrylate or methacrylate functionality, a curing composition, a filler composition comprising bioactive particles of bioactive glass, bioactive glass-ceramics, calcium phosphates, calcium apatites, or mixtures thereof and optionally one or more polymerizable acrylate or methacrylate comonomers. Degradable macromonomers are manufactured from cyclic monomers with compounds having acrylate or methacrylate functionality. Depending on their use, the degradable macromonomer compositions further comprise one or more organic or inorganic fillers, including a calcium-based compound and/or a radiopacity-imparting agent. The compositions are particularly suitable for root canal sealants, implants, bone cements, and pulp capping materials.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: September 7, 2004
    Assignee: Pentron Corporation
    Inventors: Weitao Jia, Shuhua Jin
  • Patent number: 6761760
    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 18.5×10−6/° C. in the temperature range of 250°-600° C.
    Type: Grant
    Filed: June 12, 2002
    Date of Patent: July 13, 2004
    Assignee: Pentron Corporation
    Inventors: Dmitri Brodkin, Carlino Panzera, Paul Panzera
  • Patent number: 6645285
    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: February 4, 2002
    Date of Patent: November 11, 2003
    Assignee: Pentron Corporation
    Inventors: Dmitri Brodkin, Carlino Panzera, Paul Panzera
  • Patent number: 4547531
    Abstract: A chemically curable dental restorative material is provided comprising a two-component paste-paste system wherein:(i) a first initiator-containing paste system comprises from about 15 to 40% by weight of a polymerizable methacrylic ester monomeric system comprising a cross-linking methacrylate monomer, at least one co-monomeric methacrylate diluent and a free radical-generating catalyst, and from about 60 to 85% by weight of an inorganic filler prepared by wet milling, surface etching milling and a silanizing milling; and(ii) a second accelerator-containing paste system comprises from about 15 to 31% by weight of a polymerizable methacrylic ester monomeric system comprising a cross-linking methacrylate monomer, at least one co-monomeric methacrylate diluent and an inorganic amine accelerator and from 69 to 85% by weight of an inorganic filler prepared by wet milling, surface etching milling and a silanizing milling;said first and second paste systems being admixed in substantially equal proportions to form t
    Type: Grant
    Filed: August 2, 1984
    Date of Patent: October 15, 1985
    Assignee: Pentron Corporation
    Inventor: Samuel Waknine
  • Patent number: 4544359
    Abstract: In a dental restorative material comprising 20-30% by weight of a visible light polymerizable methacrylic ester monomeric system, from about 65-79% by weight of an inorganic filler and from about 1-5% by weight of collidal fumed silica; said inorganic filler having an average particle size diameter ranging from about 0.5 to 5 microns and said collidal fumed silica having an average particle size ranging from about 0.01 to about 0.05 micron, the improvement comprising subjecting the filler to a series of milling steps comprising (1) wet milling in aqueous medium having a pH of 5-7; (2) surface etch milling in an aqueous etchant medium and (3) a silanizing milling in a silane solution.
    Type: Grant
    Filed: December 3, 1984
    Date of Patent: October 1, 1985
    Assignee: Pentron Corporation
    Inventor: Samuel Waknine