Shaded Zirconium Oxide Articles

• US 20120214134A1
• Filed: 04/27/2012
• Published: 08/23/2012
• Est. Priority Date: 04/06/2006
• Status: Abandoned Application

• Current Assignee: Ivoclar Vivadent AG
• Original Assignee: Ivoclar Vivadent AG
• Inventors: Khan, Ajmal, Panzera, Carlino, Brodkin, Dmitri G.
• Application Number:
  US13/458,667
• Publication Number:
  US 20120214134A1
• Time in Patent Office: Days
• US Class Current: 433/201.1
• CPC Class Codes: A61C 13/082 Cosmetic aspects, e.g. inlays; Determination of the colour A61C19/10 takes precedence
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: C04B 2235/3217 Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
• CPC Class Codes: C04B 2235/3224 Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
• CPC Class Codes: C04B 2235/3225 Yttrium oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3229 Cerium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3239 Vanadium oxides, vanadates or oxide forming salts thereof, e.g. magnesium vanadate
• CPC Class Codes: C04B 2235/3241 Chromium oxides, chromates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3275 Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite
• CPC Class Codes: C04B 2235/3279 Nickel oxides, nickalates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3281 Copper oxides, cuprates or oxide-forming salts thereof, e.g. CuO or Cu2O
• CPC Class Codes: C04B 2235/40 Metallic constituents or additives not added as binding phase
• CPC Class Codes: C04B 2235/404 Refractory metals
• CPC Class Codes: C04B 2235/405 Iron group metals
• CPC Class Codes: C04B 2235/443 Nitrates or nitrites
• CPC Class Codes: C04B 2235/444 Halide containing anions, e.g. bromide, iodate, chlorite
• CPC Class Codes: C04B 2235/445 Fluoride containing anions, e.g. fluosilicate
• CPC Class Codes: C04B 2235/449 Organic acids, e.g. EDTA, citrate, acetate, oxalate
• CPC Class Codes: C04B 2235/6026 Computer aided shaping, e.g. rapid prototyping
• CPC Class Codes: C04B 2235/604 Pressing at temperatures other than sintering temperatures
• CPC Class Codes: C04B 2235/608 : Green bodies or pre-forms with well-defined density
• CPC Class Codes: C04B 2235/616 : Liquid infiltration of green bodies or pre-forms
• CPC Class Codes: C04B 2235/6562 : Heating rate
• CPC Class Codes: C04B 2235/6565 : Cooling rate
• CPC Class Codes: C04B 2235/72 : Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics
• CPC Class Codes: C04B 2235/77 : Density
• CPC Class Codes: C04B 2235/96 : Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
• CPC Class Codes: C04B 2235/9661 : Colour
• CPC Class Codes: C04B 35/486 : Fine ceramics
• CPC Class Codes: C04B 35/62655 : Drying, e.g. freeze-drying, spray-drying, microwave or supercritical drying
• CPC Class Codes: C04B 35/638 : Removal thereof

Abstract

A dental article includes yttria stabilized tetragonal zirconia polycrystalline ceramic, and no more than about 0.15 wt. % of one or more coloring agents of one or more of: Fe, Er, Co, Pr, Tb, Cr, Nd, Ce, V, Eu, Ho, Ni, and Cu, oxides thereof, and combinations thereof, whereby the dental article is provided with a color corresponding to a natural tooth shade; and wherein the dental article has a flexural strength of at least about 800 MPa. Corresponding methods are also described.

Claims

1. A method for creating a shaded ceramic including the steps of:

creating three or more uniquely shaded zirconia pigment powders, each having their own characteristic hue, by combining zirconia powder with a chemical component selected from the group consisting of Fe, Er, Co, Pr, Tb, Cr, Nd, Ce, V, Eu, Ho, Ni, and Cu salts, oxides, inorganic, organic, organo-metallic compounds thereof, and combinations thereof;

mixing together unpigmented zirconia powder with one or more of said pigment powders to achieve a predetermined shade powder;

pressing said predetermined shade powder to form a green block;

drying said green block;

pre-sintering said green block.

2. A method for creating a dental ceramic comprising the method of claim 1, wherein zirconia powder comprises yttria stabilized tetragonal zirconia polycrystal (YTZP) powder.

3. A method for creating a dental ceramic comprising the method of claim 1, with the further steps of milling the block to create a desired form, and sintering said form.

4. A method for creating a dental ceramic comprising the method of claim 1, wherein the chemical component is added in the form of an aqueous or nonaqueous solution, emulsion, dispersion, gel or particulate.

5. A method for creating a dental ceramic comprising the method of claim 1, wherein three uniquely shaded pigment powders each have their own characteristic hue in the yellow, pink and gray ranges.

6. A shaded ceramic created by the method set forth in claim 1.

7. A dental ceramic prosthesis created by the method set forth in claim 1.