Lithium silicate glass ceramic

• US 7,452,836 B2
• Filed: 02/06/2006
• Issued: 11/18/2008
• Est. Priority Date: 02/08/2005
• Status: Active Grant

• Current Assignee: Ivoclar Vivadent AG
• Original Assignee: Ivoclar Vivadent AG
• Inventors: Schweiger, Marcel, Holand, Wolfram, Apel, Elke, van t'Hoen, Christian, Burke, Harald, Rheinberger, Volker M.
• Primary Examiner(s): GROUP, KARL E
• Application Number:
  US11/348,053
• Publication Number:
  US 20070042889A1
• Time in Patent Office: 1,016 Days
• Field of Search: 501/5, 106/35, 433/228.1
• US Class Current: 501/5
• CPC Class Codes: A61C 13/0004 Computer-assisted sizing or machining of dental prostheses
• CPC Class Codes: A61C 13/0006 Production methods
• CPC Class Codes: A61C 13/0022 Blanks or green, unfinished dental restoration parts
• CPC Class Codes: A61C 13/082 Cosmetic aspects, e.g. inlays; Determination of the colour A61C19/10 takes precedence
• CPC Class Codes: A61C 13/083 Porcelain or ceramic teeth A61C13/081 takes precedence; preparations A61K6/80
• CPC Class Codes: A61C 5/70 Tooth crowns; Making thereof
• CPC Class Codes: A61C 5/77 Methods or devices for making crowns
• CPC Class Codes: A61C 8/0001 Impression means for implants, e.g. impression coping
• CPC Class Codes: A61C 8/0012 characterised by the material or composition, e.g. ceramics, surface layer, metal alloy use of specific materials A61K6/00
• CPC Class Codes: A61C 8/0048 Connecting the upper structure to the implant, e.g. bridging bars A61C8/0028 takes precedence
• CPC Class Codes: A61K 6/78 Pigments
• CPC Class Codes: A61K 6/804 comprising manganese oxide
• CPC Class Codes: A61K 6/807 comprising magnesium oxide
• CPC Class Codes: A61K 6/818 comprising zirconium oxide
• CPC Class Codes: A61K 6/833 Glass-ceramic composites
• CPC Class Codes: C01B 33/32 Alkali metal silicates C01B33/24 , C01B33/26 take precedence
• CPC Class Codes: C03B 32/02 Thermal crystallisation, e.g. for crystallising glass bodies into glass-ceramic articles C03B27/012 takes precedence
• CPC Class Codes: C03C 10/0027 containing SiO2, Al2O3, Li2O as main constituents
• CPC Class Codes: C03C 10/0045 containing SiO2, Al2O3 and MgO as main constituents
• CPC Class Codes: C03C 10/0054 containing PbO, SnO2, B2O3
• CPC Class Codes: C03C 3/097 : containing phosphorus, niobium or tantalum
• CPC Class Codes: C03C 4/0021 : for dental use
• CPC Class Codes: Y10T 409/303752 : Process
• CPC Class Codes: Y10T 83/04 : Processes

Abstract

Lithium silicate materials are described which can be easily processed by machining to dental products without undue wear of the tools and which subsequently can be converted into lithium silicate products showing high strength.

Claims

1. A lithium silicate glass ceramic which comprises the following components:

2. Glass ceramic according to claim 1 which is essentially free of ZnO.

3. Glass ceramic according to claim 1, which comprises lithium metasilicate as main crystalline phase.

4. Glass ceramic according to claim 1, which comprises 0 to 2.0 wt. % of Me(II)O.

5. Glass ceramic according to claim 1, wherein Me(II)O is selected from at least one of CaO and MgO.

6. Glass ceramic according to claim 1, which comprises 0.1 to 1.0 wt. % of MgO.

7. Glass ceramic according to claim 1, wherein the molar ratio of SiO₂:

Li₂O is at least 2.2;

1.

8. Glass ceramic according to claim 1, wherein the molar ratio of Al₂O₃:

K₂O is in the range of 1;

0.5 to 1;

2.0.

9. Glass ceramic according to claim 1, which comprises 2.5 to 5.0 wt. % of Al₂O₃.

10. Glass ceramic according to claim 1, which comprises 70.0 to 73.0 wt. % of SiO₂.

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

12. Glass ceramic according to claim 1, which further comprises at least one of the following additional components

13. Glass ceramic according to claim 1, wherein the nucleating agent is at least one of P₂O₅ and compounds of the elements Pt, Ag, Cu and W.

14. Glass ceramic according to claim 1, which comprises lithium metasilicate forming more than 50 and up to 80 vol. % of the lithium silicate glass ceramic.

15. Glass ceramic according to claim 1, which is in form of a blank or a dental restoration.

16. Glass ceramic according to claim 15, wherein the dental restoration is an inlay, an onlay, a bridge, an abutment, a facing, a veneer, a facet, a crown, a partial crown, a framework or a coping.

17. Glass ceramic according to claim 1, which comprises 64.0 to 73.0 wt. % SiO₂.

18. Glass ceramic according to claim 4, which comprises 0 to 1.5 wt. % of Me(II)O.

19. Glass ceramic according to claim 7, which comprises a molar ratio of SiO₂:

Li₂O of at least 2.3;

1.

20. Glass ceramic according to claim 7, which comprises a molar ratio of SiO₂:

Li₂O in the range of 2.3;

1 to 2.5;

1.

21. Glass ceramic according to claim 8, wherein the molar ratio of Al₂O₃:

K₂O is in the range of 1;

1 to 1;

2.0.

22. Glass ceramic according to claim 1, which comprises 1.5 to 3.0 wt. % of ZrO₂.

23. Glass ceramic according to claim 11, which comprises 0.5 to 3.5 wt. % coloring and fluorescent metal oxides.