Process for the preparation of dental restorations

Patent metadata

Field	Value
Publication number	US-9956146-B2
Application number	US-201615083937-A
Country	US
Kind code	B2
Filing date	Mar 29, 2016
Priority date	Apr 16, 2010
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

The invention relates to a process for preparing dental restorations, wherein a lithium silicate glass ceramic or a lithium silicate glass is used which contains at least 8.5 wt.-% transition metal oxide selected from the group consisting of oxides of yttrium, oxides of transition metals with an atomic number from 41 to 79 and mixtures of these oxides.

First claim

The invention claimed is:

1. Lithium silicate glass ceramic, which comprises at least 14.0 wt.-% transition metal oxide selected from the group consisting of oxides of Y, Nb, La, Ta, W and mixtures of these oxides and further comprises lithium metasilicate or lithium disilicate as main crystal phase.

2. Glass ceramic according to claim 1 , which comprises more than 5 vol.-% of lithium metasilicate or lithium disilicate crystals.

3. Glass ceramic according to claim 1 , which comprises 54.0 to 80.0 wt.-% SiO 2 .

4. Glass ceramic according to claim 1 , which comprises 11.0 to 19.0 wt.-% Li 2 O.

5. Glass ceramic according to claim 1 , which comprises 0.5 to 12.0 wt.-% nucleating agent, wherein the nucleating agent is selected from P 2 O 5 , TiO 2 , and/or metals.

6. Glass ceramic according to claim 1 , which comprises further alkali metal oxide in an amount of from 0.5 to 13.5 wt.-%, wherein the further alkali metal oxide is K 2 O, Cs 2 O and/or Rb 2 O.

7. Glass ceramic according to claim 1 , which comprises up to 6.0 wt.-% alkaline earth metal oxide, wherein the alkaline earth metal oxide is CaO, BaO, MgO and/or SrO, and/or comprises up to 6.0 wt.-% ZnO.

8. Glass ceramic according to claim 1 , which comprises 0.2 to 8.0 wt.-% oxide of trivalent elements, wherein the oxide of trivalent elements is Al 2 O 3 and/or Bi 2 O 3 .

9. Glass ceramic according to claim 1 , which comprises at least one further oxide of tetravalent elements or at least one further oxide of pentavalent elements.

10. Glass ceramic according to claim 9 , wherein the at least one further oxide of tetravalent elements comprises ZrO 2 , SnO 2 or GeO 2 .

11. Glass ceramic according to claim 1 , which comprises at least one of the following components:

Component
wt.-%

SiO 2
54.0 to 80.0

Li 2 O
11.0 to 19.0

Al 2 O 3
 0.2 to 8.0

K 2 O
 0.5 to 13.5

Alkaline earth oxide
  0 to 6.0

ZnO
  0 to 6.0

Transition metal oxide
14.0 to 30.0

P 2 O 5
 0.5 to 12.0

ZrO 2
 0.1 to 4.0

Colorant and fluorescent agent
 0.1 to 8.0.

12. Glass ceramic according to claim 1 , which is present in the form of a powder, a blank or a dental restoration.

13. Glass ceramic according to claim 1 , wherein the refractive index is at least 1.53.

14. Process for the preparation of the glass ceramic according to claim 1 , in which a starting glass with the components of the glass ceramic is subjected to at least one heat treatment in the range of from 450 to 950° C.

15. Process of using the glass ceramic according to claim 1 , as a dental material, wherein the dental material is used for coating dental restorations, for the preparation of dental restorations or as filler in inorganic-organic composites.

16. Lithium silicate glass ceramic, which comprises at least 14.0 wt.-% transition metal oxide selected from the group consisting of oxides of yttrium, oxides of transition metals with an atomic number from 41 to 79 and mixtures of these oxides and further comprises lithium metasilicate or lithium disilicate as main crystal phase, which comprises at least one further oxide of pentavalent elements, wherein the at least one further oxide of pentavalent elements comprises Bi 2 O 5 .

17. Lithium silicate glass, which comprises at least 14.0 wt.-% transition metal oxide selected from the group consisting of oxides of Y, Nb, La, Ta, W and mixtures of these oxides and further comprises nuclei which are suitable for forming lithium metasilicate or lithium disilicate crystals as main crystal phase.

18. Glass according to claim 17 , wherein the refractive index is at least 1.53.

19. Glass according to claim 17 , which is present in the form of a powder, a blank or a dental restoration.

20. Lithium silicate glass ceramic, which comprises at least 18.0 wt.-% transition metal oxide selected from the group consisting of oxides of yttrium, oxides of transition metals with an atomic number from 41 to 79 and mixtures of these oxides and further comprises lithium metasilicate or lithium disilicate as main crystal phase.

21. Lithium silicate glass, which comprises at least 18.0 wt.-% transition metal oxide selected from the group consisting of oxides of yttrium, oxides of transition metals with an atomic number from 41 to 79 and mixtures of these oxides and further comprises nuclei which are suitable for forming lithium metasilicate or lithium disilicate crystals as main crystal phase.

Assignees

• Ivoclar Vivadent Ag

Inventors

• Ritzberger Christian
• Höland Wolfram
• Schweiger Marcel
• Rheinberger Volker

Classifications

• A61K6/822

  comprising rare earth metal oxides · CPC title

• A61K6/818

  comprising zirconium oxide · CPC title

• A61K6/77

  Glass · CPC title

• A61K6/824

  comprising transition metal oxides · CPC title

• A61K6/78

  Pigments · CPC title