Glass ceramic having SiO2 as main crystal phase

Patent metadata

Field	Value
Publication number	US-11091388-B2
Application number	US-201916454747-A
Country	US
Kind code	B2
Filing date	Jun 27, 2019
Priority date	May 16, 2014
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

Glass ceramics having SiO2 as main crystal phase and precursors thereof are described which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.

First claim

The invention claimed is:

1. Process for the preparation of a dental restoration in which a glass ceramic which comprises the following components

Component
wt.-%

SiO 2
58.0 to 92.0

Li 2 O
 2.0 to 10.0

and comprises SiO 2 as main crystal phase is given the shape of the desired dental restoration, wherein said dental restoration comprises a bridge, inlay, onlay, veneer, abutment, partial crown, crown or facet.

2. Process according to claim 1 , wherein the glass ceramic comprises 60.0 to 90.0 wt.-% SiO 2 .

3. Process according to claim 1 , wherein the glass ceramic comprises 2.8 to 9.0 wt.-% Li 2 O.

4. Process according to claim 1 , wherein the glass ceramic comprises 0 to 13.0 wt.-% further alkali metal oxide Me I 2 O.

5. Process according to claim 1 , wherein the glass ceramic comprises 0 to 11.0 wt.-% oxide of divalent elements Me II O.

6. Process according to claim 1 , wherein the glass ceramic comprises 0 to 10.0 wt.-% oxide of trivalent elements Me III 2 O 3 .

7. Process according to claim 1 , wherein the glass ceramic comprises 0 to 21.0 wt.-% further oxide of tetravalent elements Me IV O 2 .

8. Process according to claim 1 , wherein the glass ceramic comprises 0 to 7.0 wt.-% P 2 O 5 .

9. Process according to claim 1 , wherein the glass ceramic comprises 0 to 6.0 wt.-% further oxide of pentavalent elements Me V 2 O 5 .

10. Process according to claim 1 , wherein the glass ceramic comprises 0 to 6.0 wt.-% oxide of hexavalent elements Me VI O 3 .

11. Process according to claim 1 , wherein the glass ceramic comprises 0 to 5.0 wt.-% fluorine.

12. Process according to claim 1 , wherein the glass ceramic comprises at least one of the following components in the specified amounts:

Component
wt.-%

Me I 2 O
0 to 13.0

Me II O
0 to 11.0

Me III 2 O 3
0 to 10.0

Me IV O 2
0 to 21.0

P 2 O 5
0 to 7.0

Me V 2 O 5
0 to 6.0

Me VI O 3
0 to 6.0

fluorine
0 to 5.0.

13. Process according to claim 1 , wherein the glass ceramic comprises low quartz, cristobalite or a mixture thereof as main crystal phase.

14. Process according to claim 1 , wherein the glass ceramic comprises 5.0 to 50.0 wt.-% SiO 2 as crystal phase.

15. Process according to claim 1 , wherein the glass ceramic comprises lithium phosphate and/or lithium silicate as further crystal phase.

16. Process according to claim 1 , wherein the glass ceramic is present in the form of a powder, a frit, a blank or a dental restoration.

17. Process according to claim 1 , wherein the glass ceramic is prepared by subjecting a starting glass which comprises the following components

Component
wt.-%

SiO 2
58.0 to 92.0

Li 2 O
 2.0 to 10.0

to at least one heat treatment at a temperature of from 700 to 950° C.

18. Process according to claim 17 , wherein
(a) powder of the starting glass, optionally after the addition of further components, is pressed to form a powder compact, and
(b) the powder compact is subjected to a heat treatment at a temperature of 700 to 950° C.; or
(a′) melt of the starting glass is shaped to form a glass blank, and
(b′) the glass blank is subjected to a heat treatment at a temperature of 700 to 900° C.

19. Process according to claim 1 , wherein the glass ceramic is given the shape of the desired dental restoration by pressing, sintering or machining.

20. Process for the preparation of a dental restoration in which a starting glass which comprises the following components

Component
wt.-%

SiO 2
58.0 to 92.0

Li 2 O
 2.0 to 10.0

and comprises nuclei for the crystallization of SiO 2 is given the shape of the desired dental restoration, wherein said dental restoration comprises a bridge, inlay, onlay, veneer, abutment, partial crown, crown or facet.

Assignees

• Ivoclar Vivadent Ag

Inventors

• Rampf Markus
• Dittmer Marc
• Ritzberger Christian
• Schweiger Marcel
• Höland Wolfram

Classifications

• C03C10/0009 Primary

  containing silica as main constituent · CPC title

• C03C4/0021

  for dental use · CPC title

• C03C3/085

  containing an oxide of a divalent metal · CPC title

• A61K6/836

  Glass · CPC title

• A61K6/833

  Glass-ceramic composites · CPC title