Patents by Inventor Yohji Imai

Yohji Imai 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).

  • Publication number: 20040157954
    Abstract: The bone cement composition of the present invention comprises a liquid component including ethyl methacrylate as the main component and a powder component including an ethyl methacrylate/methyl methacrylate copolymer as the main component.
    Type: Application
    Filed: February 3, 2004
    Publication date: August 12, 2004
    Inventors: Yohji Imai, Yoshinori Kadoma, Kazuo Takakuda, Sadao Morita
  • Patent number: 6585514
    Abstract: To dissolve a calcium hydroxide-based root canal filler having been carbonated and fixed within a root canal, which cannot be removed from the root canal by means of a reamer and a file, during doing the root canal treatment again, and to sterilize the root canal, the solubilizing agent of the carbonated calcium hydroxide-based root canal filler includes water containing 1 to 60% by weight of the whole of at least one acid selected from the group consisting of phosphoric acid, gluconic acid, fumaric acid, lactic acid, glycolic acid, propionic acid, malic acid, maleic acid, citric acid, succinic acid, tartaric acid, acetic acid, glycerophosphoric acid, and malonic acid; and 0.1 to 30% by weight of the whole of at least one sterilizing properties-imparting agent selected from the group consisting of an iodine preparation, a surfactant, a bactericide, hydrogen peroxide, and limonene.
    Type: Grant
    Filed: February 15, 2002
    Date of Patent: July 1, 2003
    Assignee: GC Corporation
    Inventors: Yohji Imai, Masao Abiru, Kimihiko Sato
  • Patent number: 6566418
    Abstract: A calcium hydroxide-based root canal filling material having superior bioaffinity is provided, which is a temporary root canal filling material to be used in the root canal treatment of teeth, having such roles that, when filled temporarily in the root canal, it stays in an affected part during a predetermined period of time, thereby a root canal being prevented from staining by pathogenic bacteria or exudates, has corrosion resistance, and promotes the remedy of an apical abscess by wound of the root apex portion. The calcium hydroxide-based root canal filling material is comprised of 3 to 20% by weight of polyvinylpyrrolidone and/or polyvinyl methyl ether, 30 to 60% by weight of calcium hydroxide, and 35 to 60% by weight of water. Further, there is an embodiment in which from 5 to 20 parts by weight of at least one X-ray opacity medium selected from barium sulfate, zirconium oxide, bismuth subnitrate, bismuth trioxide, and bismuth carbonate and/or 0.
    Type: Grant
    Filed: January 25, 2001
    Date of Patent: May 20, 2003
    Assignee: GC Corporation
    Inventors: Yohji Imai, Masao Abiru
  • Publication number: 20020198283
    Abstract: A calcium hydroxide-based root canal filling material having superior bioaffinity is provided, which is a temporary root canal filling material to be used in the root canal treatment of teeth, having such roles that, when filled temporarily in the root canal, it stays in an affected part during a predetermined period of time, thereby a root canal being prevented from staining by pathogenic bacteria or exudates, has corrosion resistance, and promotes the remedy of an apical abscess by wound of the root apex portion. The calcium hydroxide-based root canal filling material is comprised of 3 to 20% by weight of polyvinylpyrrolidone and/or polyvinyl methyl ether, 30 to 60% by weight of calcium hydroxide, and 35 to 60 % by weight of water. Further, there is an embodiment in which from 5 to 20 parts by weight of at least one X-ray opacity medium selected from barium sulfate, zirconium oxide, bismuth subnitrate, bismuth trioxide, and bismuth carbonate and/or 0.
    Type: Application
    Filed: January 25, 2001
    Publication date: December 26, 2002
    Applicant: GC CORPORATION
    Inventors: Yohji Imai, Masao Abiru
  • Publication number: 20020164558
    Abstract: To dissolve a calcium hydroxide-based root canal filler having been carbonated and fixed within a root canal, which cannot be removed from the root canal by means of a reamer and a file, during doing the root canal treatment again, and to sterilize the root canal, the solubilizing agent of the carbonated calcium hydroxide-based root canal filler includes water containing 1 to 60% by weight of the whole of at least one acid selected from the group consisting of phosphoric acid, gluconic acid, fumaric acid, lactic acid, glycolic acid, propionic acid, malic acid, maleic acid, citric acid, succinic acid, tartaric acid, acetic acid, glycerophosphoric acid, and malonic acid; and 0.1 to 30% by weight of the whole of at least one sterilizing properties-imparting agent selected from the group consisting of an iodine preparation, a surfactant, a bactericide, hydrogen peroxide, and limonene.
    Type: Application
    Filed: February 15, 2002
    Publication date: November 7, 2002
    Applicant: GC Corporation
    Inventors: Yohji Imai, Masao Abiru, Kimihiko Sato
  • Patent number: 5739231
    Abstract: A metal surface treatment agent is disclosed, comprising: (a) from 0.001 to 10% by weight of a polymerizable monomer containing a thiophosphoric acid chloride group therein and (b) from 0.001 to 10% by weight of a polymerizable monomer containing a phosphoric acid ester group therein, and optionally, (c) from 0.1 to 5% by weight of a polymerization initiator dissolved in an organic solvent.
    Type: Grant
    Filed: April 7, 1995
    Date of Patent: April 14, 1998
    Assignee: GC Corporation
    Inventors: Yohji Imai, Yosuke Taira, Tetsuro Sakuma
  • Patent number: 5290172
    Abstract: A method for treating a tooth surface to make it bondable well enough for dental purposes involves treating enamel and dentin with a primer comprising a) an organic acid, b) an iron, copper or cobalt salt and c) water, and then curing the tooth surface with a bonding material comprising d) a methacrylate or acrylate having at least one unsaturated double bond, e) a (thio)barbituric acid derivative and f) a polymerization initiator.
    Type: Grant
    Filed: August 31, 1992
    Date of Patent: March 1, 1994
    Assignee: GC Corporation
    Inventors: Tetsuro Sakuma, Yohji Imai
  • Patent number: 5288341
    Abstract: An agent is characterized by containing a polymerizable monomer having a thiophosphoric acid dichloride group. By applying this agent to the surfaces of noble metals, much more durable and increased bond strength is obtained.
    Type: Grant
    Filed: September 11, 1992
    Date of Patent: February 22, 1994
    Assignee: GC Corporation
    Inventors: Katsunori Kojima, Yohji Imai, Tetsuro Sakuma
  • Patent number: 5252629
    Abstract: An adhesive showing a strong bonding effect on dentin characterized by comprising in combination a primer comprising a water-miscible monomer and a salt of copper, iron or cobalt, and a curing composition comprising a methacrylate monomer and a polymerization initiator containing a (thio)barbituric acid derivative as one component.
    Type: Grant
    Filed: April 17, 1992
    Date of Patent: October 12, 1993
    Assignee: GC Corporation
    Inventors: Yohji Imai, Shigenobu Kusakai
  • Patent number: 5234971
    Abstract: An odontotherapeutical material is based on two liquids A and B containing materials capable of forming difficult-to-dissolve precipitations immediately by mixing. The liquids A and B are successively applied on the affected region.
    Type: Grant
    Filed: November 25, 1991
    Date of Patent: August 10, 1993
    Assignee: G-C Dental Industrial Corp.
    Inventors: Yohji Imai, Takahiro Akimoto
  • Patent number: 4957437
    Abstract: An artifical tooth comprises a contacting member formed of a composite material having compatibility with living tissues and diaposed at an outer portion of the artificial tooth to be contacted with alveolar bone, a metal base member having an opening therein and disposed inside of and attached to the contacting member, a metal post inserted into the opening of the metal base member and at least two elastic buffer members disposed in a space between the metal base member and the metal post. The composite material having compatibility with living tissues contains 40 to 95% by weight of a calcium phosphate compound and 60 to 5% by weight of an organic polymer. Each of the elastic buffer members is spaced apart for movably receiving the metal post by which pressure imposed upon the artificial tooth is transmitted.
    Type: Grant
    Filed: February 16, 1989
    Date of Patent: September 18, 1990
    Assignee: Mitsubishi Mining & Cement Co., Ltd.
    Inventors: Kaizo Shimura, Hiroyasu Takeuchi, Masahiro Hirano, Yohji Imai