Patents by Inventor Kei Nakashima

Kei Nakashima 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: 20240000670
    Abstract: Provided are a zirconia dental mill blank and a manufacturing method therefor, said mill bank having a to-be-cut part composed of a composite material, which includes fine particles of an inorganic oxide (excluding zirconium oxide, an inorganic oxide functioning as a stabilizer, and aluminum oxide) and a matrix composed of a temporarily sintered body of a crystalline zirconium oxide powder containing a stabilizer and an aluminum oxide additive, wherein the temporarily sintered body is a microporous temporarily sintered body having a relative density of 45-65% and having pores opened outward, and the fine particles of the inorganic oxide are held in the pores of the microporous temporarily sintered body. Moreover, provided are a method for manufacturing a dental zirconia ceramic prosthesis, and a method for manufacturing an article composed of a zirconia composite ceramic.
    Type: Application
    Filed: October 22, 2021
    Publication date: January 4, 2024
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Hiroshi Hara, Akari Hashimoto, Kei Nakashima
  • Patent number: 11759297
    Abstract: Provided is a reference denture alignment jig which guides reference dentures into an oral cavity or to an articulator in which upper and lower edentulous jaw models are fixed, and aligns the reference dentures in the oral cavity or in the articulator in which upper and lower edentulous jaw models are fixed, the jig having a reference denture holding portion for holding reference dentures.
    Type: Grant
    Filed: May 10, 2018
    Date of Patent: September 19, 2023
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Tatsuya Yamazaki, Kei Nakashima, Youichi Yamamoto, Hitoshi Motohashi
  • Publication number: 20210137652
    Abstract: Provided is a reference denture alignment jig which guides reference dentures into an oral cavity or to an articulator in which upper and lower edentulous jaw models are fixed, and aligns the reference dentures in the oral cavity or in the articulator in which upper and lower edentulous jaw models are fixed, the jig having a reference denture holding portion for holding reference dentures.
    Type: Application
    Filed: May 10, 2018
    Publication date: May 13, 2021
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Tatsuya YAMAZAKI, Kei NAKASHIMA, Youichi YAMAMOTO, Hitoshi MOTOHASHI
  • Patent number: 10973740
    Abstract: The present invention provides a powder-liquid type denture base liner comprising: a powder material including (A) uncrosslinked resin particles, (B) an organic peroxide, (C) a pyrimidine trione derivative, and (D) an organic metal compound; and a liquid material including (E) a radical polymerizable monomer and (F) an aromatic amine compound, wherein the powder-liquid denture base liner is characterized in that the (C) pyrimidine trione derivative is 0.0002-1.0 mass parts per 100 mass parts of (E) radical polymerizable monomer.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: April 13, 2021
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Miki Hitomi, Ayumu Gyakushi, Kei Nakashima
  • Publication number: 20190216689
    Abstract: The present invention provides a powder-liquid type denture base liner comprising: a powder material including (A) uncrosslinked resin particles, (B) an organic peroxide, (C) a pyrimidine trione derivative, and (D) an organic metal compound; and a liquid material including (E) a radical polymerizable monomer and (F) an aromatic amine compound, wherein the powder-liquid denture base liner is characterized in that the (C) pyrimidine trione derivative is 0.0002-1.0 mass parts per 100 mass parts of (E) radical polymerizable monomer.
    Type: Application
    Filed: July 20, 2017
    Publication date: July 18, 2019
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Miki HITOMI, Ayumu GYAKUSHI, Kei NAKASHIMA
  • Publication number: 20190083210
    Abstract: A maxilla standard dental plate configured so that if the length of a line segment PQ which connects a point P corresponding to the left-side pterygomaxillary notch at the plate posterior border and a point Q corresponding to the right-side pterygomaxillary notch at the plate posterior border is 1, the length of a line segment OM which connects a point O corresponding to the maxillary labial frenulum at the exact middle of the labial denture border and a median point M of the line segment PQ is 0.76-0.98.
    Type: Application
    Filed: August 26, 2016
    Publication date: March 21, 2019
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Kei NAKASHIMA, Tatsuya YAMAZAKI, Ayumu GYAKUSHI, Miki HITOMI, Koji MATSUSHIGE, Masanao HASHIGUCHI
  • Patent number: 9931180
    Abstract: A dental powder/liquid material-containing preparation accommodation bag, which suppresses entrainment of air in mixing a powder material and a liquid material for dispensing, is provided. A powder material 8 is accommodated in a powder material accommodation chamber 3 of a bag body 2, while a liquid material 9 dissolving the powder material 8 and changing into a pasty form, in cooperation with the powder material 8 is accommodated in a liquid material accommodation chamber 4 partitioned from the powder material accommodation chamber 3 by a weakened section 7. The weakened section 7 is ruptured by applying a pressing force to the bag body 2. As a result, the powder material accommodation chamber 3 and the liquid material accommodation chamber 4 communicate, to feed the liquid material accommodated in the liquid material accommodation chamber 4 into the powder material accommodation chamber 3.
    Type: Grant
    Filed: May 14, 2014
    Date of Patent: April 3, 2018
    Assignee: Tokuyama Dental Corporation
    Inventors: Masanao Hashiguchi, Nobutoshi Yamaguchi, Kei Nakashima
  • Patent number: 9549879
    Abstract: A powder-liquid dental curable material kit composed of (A) a liquid material and (B) a powder material, wherein the liquid material (A) contains (a1) a radically polymerizable (meth)acrylic monomer, (a2) an organic halogen compound and (a3) a radical chain transfer agent; the powder material (B) contains (b1) non-crosslinked resin particles, (b2) a pyrimidinetrione compound and (b3) an organic metal compound; and (Z) a peroxide is blended in at least one of the liquid material (A) and the powder material (B). This curable material kit is capable of reducing the heat generation during the curing of a curable material which is a mixture of the liquid material (A) and the powder material (B) and is not susceptible to the excessive prolongation of the curing time even when the curable material is cured by a brush-on technique, thereby ensuring an appropriate curing time for both of a brush-on technique and a kneading technique.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: January 24, 2017
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Megumi Sato, Kei Nakashima, Koji Matsushige
  • Publication number: 20160106519
    Abstract: A dental powder/liquid material-containing preparation accommodation bag, which suppresses entrainment of air in mixing a powder material and a liquid material for dispensing, is provided. A powder Material 8 is accommodated in a powder material accommodation chamber 3 of a bag body 2, while a liquid material 9 dissolving the powder material 8 and changing into a pasty form, in cooperation with the powder material 8 is accommodated in a liquid material accommodation chamber 4 partitioned from the powder material accommodation chamber 3 by a weakened section 7. The weakened section 7 is ruptured by applying a pressing force to the bag body 2. As a result, the powder material accommodation chamber 3 and the liquid material accommodation chamber 4 communicate, to feed the liquid material accommodated in the liquid material accommodation chamber 4 into the powder material accommodation chamber 3.
    Type: Application
    Filed: May 14, 2014
    Publication date: April 21, 2016
    Inventors: Masanao HASHIGUCHI, Nobutoshi YAMAGUCHI, Kei NAKASHIMA
  • Publication number: 20150038614
    Abstract: A powder-liquid dental curable material kit composed of (A) a liquid material and (B) a powder material, wherein the liquid material (A) contains (a1) a radically polymerizable (meth)acrylic monomer, (a2) an organic halogen compound and (a3) a radical chain transfer agent; the powder material (B) contains (b1) non-crosslinked resin particles, (b2) a pyrimidinetrione compound and (b3) an organic metal compound; and (Z) a peroxide is blended in at least one of the liquid material (A) and the powder material (B). This curable material kit is capable of reducing the heat generation during the curing of a curable material which is a mixture of the liquid material (A) and the powder material (B) and is not susceptible to the excessive prolongation of the curing time even when the curable material is cured by a brush-on technique, thereby ensuring an appropriate curing time for both of a brush-on technique and a kneading technique.
    Type: Application
    Filed: March 5, 2013
    Publication date: February 5, 2015
    Inventors: Megumi Sato, Kei Nakashima, Koji Matsushige
  • Patent number: D897539
    Type: Grant
    Filed: January 4, 2019
    Date of Patent: September 29, 2020
    Assignee: Tokuyama Dental Corporation
    Inventors: Tatsuya Yamazaki, Kei Nakashima, Youichi Yamamoto, Hitoshi Motohashi