Lithium silicate glass ceramic for fabrication of dental appliances

Patent metadata

Field	Value
Publication number	US-9241879-B2
Application number	US-201113374040-A
Country	US
Kind code	B2
Filing date	Dec 8, 2011
Priority date	Apr 11, 2008
Publication date	Jan 26, 2016
Grant date	Jan 26, 2016

Abstract

The present invention relates to a method of fabricating an improved lithium silicate glass ceramic and to that material for the manufacture of blocks for dental appliances using a CAD/CAM process and hot pressing system. The lithium silicate material has a chemical composition that is different from those reported in the prior art with 1 to 10% of germanium dioxide in final composition. The softening points are close to the crystallization final temperature of 800° C. indicating that the samples will support the temperature process without shape deformation.

First claim

I claim:

1. A lithium silicate ceramic glass made from a composition mixture comprising:
53% to 59% wt of SiO 2 ;
14% to 19% wt of Li 2 O;
1% to 9% wt of GeO 2 ; and
coloring oxides.

2. The lithium silicate ceramic glass recited in claim 1 wherein said composition mixture also comprises at least one of the following components: Al 2 O 3 , K 2 O, B 2 O 3 , CaO, MgO, CeO 2 , P 2 O 5 , ZrO 2 , TiO 2 , Er 2 O 3 , V 2 O 5 , Ta 2 O 5 , Sm 2 O 3 , Pr 2 O 3 , and Eu 2 O 3 .

3. A lithium silicate ceramic glass made from a composition mixture comprising:
53% to 59% wt of SiO 2 ;
14to 19% wt of Li 2 O;
1% to 9% wt of GeO 2 ;

wherein the molar ratio of SiO 2 /Li 2 O is between 1.8 and 1.9.

4. The lithium silicate ceramic glass recited in claim 3 wherein said composition mixture also comprises at least one of the following components:
Al 2 O 3 , K 2 O, B 2 O 3 , CaO, MgO, CeO 2 , P 2 O 5 , ZrO 2 , TiO 2 , Er 2 O 3 , V 2 O 5 , Ta 2 O 5 , Sm 2 O 3 , Pr 2 O 3 , and Eu 2 O 3 .

5. A lithium silicate dental ceramic glass article comprising:
silicon dioxide (SiO 2 ), lithium oxide (Li 2 O), and germanium oxide (GeO 2 ), wherein a molar ratio of SiO 2 /Li 2 O is between 1.8 and 1.9.

6. The lithium silicate dental ceramic glass article recited in claim 5 , wherein the article is fully crystallized and a crystal structure of the article comprises lithium silicate (Li 2 SiO 3 ).

7. The lithium silicate dental ceramic glass article recited in claim 5 , wherein the article is fully crystallized and a crystal structure of the article comprises only lithium silicate (Li 2 SiO 3 ).

Assignees

• Castillo Rodolfo
• Glidewell James R Dental Ceramics Inc

Inventors

• Castillo Rodolfo

Classifications

• A61K6/807

  comprising magnesium oxide · CPC title

• A61K6/804

  comprising manganese oxide · CPC title

• A61K6/833

  Glass-ceramic composites · CPC title

• A61K6/818

  comprising zirconium oxide · CPC title

• A61K6/78

  Pigments · CPC title