Patents by Inventor Richard L. Dunn

Richard L. Dunn has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4938763
    Abstract: A biodegradable polymer is provided for use in providing syringeable, in-situ forming, solid biodegradable implants for animals. The polymer is placed into the animal in liquid form and cures to form the implant in-situ. A thermoplastic system to form said implant comprises the steps of dissolving a non-reactive polymer in biocompatible solvent to form a liquid, placing the liquid within the animal, and allowing the solvent to dissipate to produce the implant. An alternative, thermosetting system comprises mixing together effective amounts of a liquid acrylic ester terminated, biodegradable prepolymer and a curing agent, placing the liquid mixture within an animal and allowing the prepolymer to cure to form the implant. Both systems provide a syringeable, solid biodegradable delivery system by the addition of an effective level of biologically active agent to the liquid before injection into the body.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: July 3, 1990
    Inventors: Richard L. Dunn, James P. English, Donald R. Cowsar, David P. Vanderbilt
  • Patent number: 4932972
    Abstract: A prosthetic ligament assembly includes a nonaugmented prosthetic ligament for permanently replacing a natural ligament spanning first and second body members, such as the femur and tibia, and a bone screw adapted for tensioning the prosthetic ligament during implantation. The prosthetic ligament includes a load bearing member intertwined into a plain braid from a plurality of biocompatible, high strength, ultra high molecular weight polyethylene yarns. Each yarn includes at least fifty fibers and has a tensile strength greater than or equal to about 100,000 psi. The load bearing member has a gage section and a loop at each end thereof for anchoring the load bearing member to the body members. The load bearing member is preloaded to remove slack therefrom. The load bearing member may be used alone or may be formed into a hollow braid having a core disposed within the hollow portion of the braid to permit radiographic visualization of the prosthetic ligament.
    Type: Grant
    Filed: April 26, 1988
    Date of Patent: June 12, 1990
    Assignee: Richards Medical Company
    Inventors: Richard L. Dunn, Danny H. Lewis, Thomas W. Sander, James A. Davidson, Neil B. Beals, Yancy L. Gill
  • Patent number: 4841968
    Abstract: The controlled first-order release of either an antithrombotic or thrombolytic agent from a sutures at an anastomosis site is disclosed which prevents postoperative thrombosis and improves vascular patency in animals. A suitable polymer, such as polycaprolactone, is blended with prostacyclin or analogues of prostacyclin to form the suture material.
    Type: Grant
    Filed: September 26, 1986
    Date of Patent: June 27, 1989
    Assignees: Southern Research Institute, Texas Health Science Center
    Inventors: Richard L. Dunn, John W. Gibson, Carlton A. Eddy, Leonard E. Laufe
  • Patent number: 4804691
    Abstract: A method for making an adhesive for use in joining soft living tissue including the steps of preparing a hydroxyl-terminated polyester by reacting a biodegradable monomer with a polyhydroxy polymerization initiator in the presence of an amount up to about 2.0 weight percent of a catalyst, and then preparing a diisocyanate-terminated prepolymer adhesive by reacting about 24 to 92 weight percent of the hydroxy-terminated polyester with about 8 to 76 weight percent excess aromatic diisocyante. The polyester and the diisocyanate are preferably dissolved in an organic solvent prior to the mixture thereof in a ratio of solids to solvent of about 60:40. The polyester is a polymer or copolymer of lactide, glycolide or .epsilon.-caprolactone. The initiator is ethylene glycol, diethylene glycol, pentaerythritol or 1,1,1-tris (hydroxymethyl) ethane. The catalyst is stannous octoate, a zinc compound, an aliphatic tertiary amine, dibutyltin diacetate or 1,4-diazabicyclo [2,2,2] octane.
    Type: Grant
    Filed: August 28, 1987
    Date of Patent: February 14, 1989
    Assignee: Richards Medical Company
    Inventors: James P. English, Gerald W. McNeely, Richard L. Dunn
  • Patent number: 4790850
    Abstract: A prosthetic ligament assembly includes a nonaugmented prosthetic ligament for permanently replacing a natural ligament spanning first and second body members, such as the femur and tibia, and a bone screw adapted for tensioning the prosthetic ligament during implantation. The prosthetic ligament includes a load bearing member intertwined into a plain braid from a plurality of biocompatible, high strength, ultra high molecular weight polyethylene yarns. Each yarn includes at least fifty fibers and has a tensile strength greater than or equal to about 100,000 psi. The load bearing member has a gage section and a loop at each end thereof for anchoring the load bearing member to the body members. The load bearing member is preloaded to remove slack therefrom. The load bearing member may be used alone or may be formed into a hollow braid having a core disposed within the hollow portion of the braid to permit radiographic visualization of the prosthetic ligament.
    Type: Grant
    Filed: June 22, 1987
    Date of Patent: December 13, 1988
    Assignee: Richards Medical Company
    Inventors: Richard L. Dunn, Danny H. Lewis, Thomas W. Sander, James A. Davidson, Neil B. Beals, Yancy L. Gill
  • Patent number: 4784699
    Abstract: The invention provides a process for decontaminating military nerve agents and blister agents. The process involves contacting the nerve agent and blister agent, particularly clothing and other items contaminated therewith, with gaseous ozone or chlorine dioxide, whereby the agents are oxidized to non-toxic products and thereby decontaminated rapidly, e.g. within a few minutes. The treatment with ozone or chlorine dioxide does not seriously affect the mechanical properties of the contaminated materials, such as fabrics.
    Type: Grant
    Filed: April 8, 1987
    Date of Patent: November 15, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Donald R. Cowsar, Richard L. Dunn, Robert A. Casper
  • Patent number: 4731084
    Abstract: A nonaugmented prosthetic ligament for permanently replacing a natural ligament spanning first and second body members, such as the femur and tibia includes a load bearing member formed from a plurality of biocompatible polyolefin fibers positioned at angles of from 0.degree. to 55.degree. relative to the longitudinal axis of the load bearing member. Each fiber is less than 100 microns in diameter and has a tensile strength greater than or equal to about 50,000 psi. The load bearing member may be used alone or may be formed into a hollow braid having a core disposed within the hollow portion of the braid to provide shape for the load bearing member. A sheath may be friction fit or molded onto the exterior of the load bearing member to prevent abrasion of the fibers.
    Type: Grant
    Filed: March 14, 1986
    Date of Patent: March 15, 1988
    Assignee: Richards Medical Company
    Inventors: Richard L. Dunn, Danny H. Lewis, Thomas W. Sander, Richard W. Treharne, III
  • Patent number: 4655777
    Abstract: Method of producing biodegradable prostheses comprising a composite of resorbable fibers reinforcing a biodegradable polymer matrix and the use thereof in medical applications such as bone plates and other orthopedic devices. The fibers include ceramic powders, .beta.-TCP and CaAl and a biodegradable glass, CMP.
    Type: Grant
    Filed: December 19, 1983
    Date of Patent: April 7, 1987
    Assignee: Southern Research Institute
    Inventors: Richard L. Dunn, Robert A. Casper
  • Patent number: 4650488
    Abstract: A prosthetic device formed of a biodegradable material and useful as a ventilation tube for insertion between the middle ear and the outer ear. The device includes a shaft with an axial passage, an inner flange and an outer flange. At least a portion of the outer surface of the shaft is tapered, with the taper increasing from the inner to the outer flange. The larger diameter outer flange and any attached portion of the shaft are, therefore, forced outwardly when the tapered portion of the shaft is in contact with animal tissue biodegrades before other portions of the prosthesis.
    Type: Grant
    Filed: May 16, 1984
    Date of Patent: March 17, 1987
    Assignee: Richards Medical Company
    Inventors: F. Barry Bays, Richard L. Dunn, Sam Marchand, Richard W. Treharne, III
  • Patent number: 4589880
    Abstract: A disposable, spermicide-releasing intravaginal contraceptive barrier formed from a homogeneous blend mixture of a thermoplastic polymer, a water-soluble polymer and a spermicide which is released at a controlled rate sufficient to provide contraceptive action for a period of up to 48 hours and methods of making the same.
    Type: Grant
    Filed: July 14, 1983
    Date of Patent: May 20, 1986
    Assignee: Southern Research Institute
    Inventors: Richard L. Dunn, Richard N. Terry, Donald R. Cowsar, Robert A. Casper
  • Patent number: 4582052
    Abstract: A fibrous article is formed of a polymer composition which incorporates povidone-iodine and provides for its sustained release.
    Type: Grant
    Filed: July 19, 1984
    Date of Patent: April 15, 1986
    Assignee: Repromed, Inc.
    Inventors: Richard L. Dunn, Danny H. Lewis, Leonard E. Laufe
  • Patent number: 4469671
    Abstract: A contraceptive device for intravaginal use comprising a bioinsoluble, biocompatible polyurethane and an acrosin inhibitor.
    Type: Grant
    Filed: February 22, 1983
    Date of Patent: September 4, 1984
    Assignee: Eli Lilly and Company
    Inventors: Ronald E. Zimmerman, Philip J. Burck, Richard L. Dunn