High-strength, translucent mg-high quartz mixed crystal glass ceramics

Patent metadata

Field	Value
Publication number	US-2016051451-A1
Application number	US-201414781510-A
Country	US
Kind code	A1
Filing date	Mar 27, 2014
Priority date	Apr 2, 2013
Publication date	Feb 25, 2016
Grant date	—

Abstract

The invention relates to the use of glass ceramics based on a high quartz mixed crystal system for dental purposes, which can be easily mechanically processed in an intermediate stage of crystallization and present high-strength, highly translucent and chemically stable glass ceramics following complete crystallization, wherein said glass or ceramics still have phosphorus and a transition metal compound, selected from titanium and zirconium or a mixture thereof.

First claim

What is claimed is:

1 . Use of a magnesium oxide/aluminum oxide/silicon oxide glass or glass ceramics for application in dentistry, wherein said glass or glass ceramics have phosphorus and a transition metal compound, selected from the group consisting of titanium and zirconium or a mixture thereof.

2 . Use of a magnesium oxide/aluminum oxide/silicon oxide glass or glass ceramics according to claim 1 , wherein said magnesium oxide/aluminum oxide/silicon oxide glass or glass ceramics is a pure oxide glass.

3 . Use of a magnesium oxide/aluminum oxide/silicon oxide glass or glass ceramics according to claim 1 , having the following composition:

SiO 2
30-60 MA

P 2 O 5
3.5-15 MA 

Al 2 O 3
12-30 MA

MgO
 5-20 MA

Σ(TiO 2 + ZrO 2 )
 5-20 MA

Σ M x O y
  0-15 MA,

wherein M is selected from the group consisting of yttrium, lanthanum, cerium, germanium, tantalum, and boron.

4 . Use of a magnesium oxide/aluminum oxide/silicon oxide glass or glass ceramics according to claim 3 having the following composition:

SiO 2
35-55 MA

P 2 O 5
 5-15 MA

Al 2 O 3
16-27 MA

MgO
6-14.5 MA 

Σ(TiO 2 + ZrO 2 )
 5-15 MA

Σ M x O y
  0-12 MA.

5 . Use of a magnesium oxide/aluminum oxide/silicon oxide glass or glass ceramics according to claim 1 , wherein the primary crystalline phase is a magnesium high quartz mixed crystal.

6 . Use of a magnesium oxide/aluminum oxide/silicon oxide glass or glass ceramics according to claim 1 , comprising a crystalline phase consisting of lanthanum phosphate.

7 . Use according to claim 1 by means of CAD/CAM and/or for chairside applications.

8 . Use according to claim 1 , wherein said glass or glass ceramics have additional transition metal cations and are used as dental coloring.

9 . Use according to claim 1 , wherein a fluorescence additive is added to said glass or glass ceramics to produce a fluorescence effect emulating nature, preferably selected from cations of rare-earth elements, particularly preferably from Er 3+ , Eu 3+ , Tb 3+ , Pr 3+ , and Gd 3+ .

10 . Use according to claim 1 , comprising:
melting glass at temperatures between 1500 and 1800° C., active or passive cooling of said glass to room temperature, causing a first crystallization by heating said glass to 750 to less than 900° C. for between 20 minutes and 4 hours, wherein glass ceramics capable of being readily processed are produced, active or passive cooling of said glass ceramics obtained to room temperature, causing a second crystallization by heating said glass to above 900° C. for a up to 120 minutes, during which the first crystallization is caused, wherein said glass ceramics produced by the first crystallization are mechanically processed, wherein said mechanical processing stage comprises the production of a substitute usable in dentistry, preferably a crown, an onlay or an inlay, from a respective blank.

11 . Use according to claim 10 , wherein the second crystallization is conducted for no more than 80 minutes.

12 . Use according to claim 10 , wherein the first crystallization is conducted in two stages, wherein the first stage occurs at 750-800° C., preferably at approximately 780° C., and the second stage occurs at 820-880° C., preferably at approximately 850° C.

13 . Use according to claim 10 , wherein the second crystallization occurs at 950-1025° C., provided that the selected temperature is not more than 150K above that of the first crystallization.

Assignees

• Fraunhofer Ges Forschung

Inventors

• Durschang Bernhard
• Probst Joern
• Katzschmann Axel

Classifications

• A61K6/816

  comprising titanium oxide · CPC title

• A61K6/807

  comprising magnesium oxide · CPC title

• A61K6/838 Primary

  Phosphorus compounds, e.g. apatite · CPC title

• A61K6/818

  comprising zirconium oxide · CPC title

• A61K6/824

  comprising transition metal oxides · CPC title