Patents Assigned to Shiken Corporation
  • Patent number: 9113986
    Abstract: The denture has the root of an artificial tooth embedded in a denture base molded from plastic. The artificial tooth is provided with a through-hole in the root that fills with denture base plastic, and the openings at both ends of the through-hole are embedded in the denture base. Further, both ends of the through-hole open at artificial tooth surfaces that face adjacent teeth, and an air-vent is provided that connects with the through-hole. The opening for the air-vent is positioned on a lingual side surface of the artificial tooth that is exposed from the denture base. Plastic that forms the denture base flows into the through-hole and air-vent embedding and retaining the root of the artificial tooth in the denture base.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: August 25, 2015
    Assignee: SHIKEN CORPORATION
    Inventor: Takahiro Shima
  • Patent number: 6210160
    Abstract: A cover for a working cast makes it extremely easy to mount and dismount a working cast to and from an articulator, improves workability, and keeps the working cast as pollution-free as possible. An articulator is also proposed. The articulator has a base and a support member each carrying a rotatable and pivotable retainer plate. Each retainer plate can be fixed in position by turning a knob. Each retainer plate has a magnet plate on its outer surface. On the other hand, a base portion of a master model having a tooth portion is kept covered with the cover when molded. The cover has on its bottom surface a magnet plate. By magnetic attraction between the magnet plates of the cover and one of the retainer, the master model can be mounted on the articulator. On the other hand, a tooth portion of an antagonist model is fixed to a base member.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: April 3, 2001
    Assignee: Shiken Corporation
    Inventor: Fumio Shima
  • Patent number: 5938442
    Abstract: Coupled artificial teeth which minimize the shaping work of gum when manufacturing a denture model and eliminates residues in the plaster mold are disclosed. A coupled artificial tooth assembly includes a plurality of teeth coupled together only by wax. On the front side of the gum, the wax covers a base portion of each of the artificial teeth and fills the interdental papillae, while exposing the tooth crowns. On the backside of the gum, the wax fills the space around the bottom portion of each of the artificial teeth so that the bottom portion is almost completely exposed. The backside of the gum is substantially flush with the bottom portions of the artificial teeth and forms a bow-shaped curved surface similar in shape to a real human gum.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: August 17, 1999
    Assignee: Shiken Corporation
    Inventor: Fumio Shima
  • Patent number: 5904481
    Abstract: A sample of artificial teeth and gums of a display unit for dental surgeons arranges plural artificial tooth samples forming the anterior teeth along the natural arch of the teeth. The artificial tooth samples are fixed and arranged on an artificial gum sample tinted with a determined color. The artificial gum sample has an inner face designed with a contact face curved to a form allowing it to be aligned close to the gum of the anterior teeth of the patient. A handle allowing the artificial gum samples to be aligned with the gum of the patient is fixed to the artificial tooth samples or to the artificial gum sample. With samples of the artificial tooth and gum, the artificial tooth samples and artificial gum samples are both aligned along the anterior teeth of the patient by holding the handles, allowing the patient to decide the color, shape and teeth arrangement of the artificial teeth and the artificial gum.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: May 18, 1999
    Assignee: Shiken Corporation
    Inventor: Fumio Shima