CeO2-stabilized ZrO2 ceramics for dental applications

Patent metadata

Field	Value
Publication number	US-10315958-B2
Application number	US-201314409801-A
Country	US
Kind code	B2
Filing date	Jun 20, 2013
Priority date	Jun 20, 2012
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

The present invention is directed to a porous pre-densified CeO 2 stabilized ZrO 2 ceramic having a density of 50.0 to 95.0%, relative to the theoretical density of zirconia, and an open porosity of 5 to 50% as well as to ceramic having a density of 97.0 to 100.0%, relative to the theoretical density of zirconia, and wherein the grains of the ceramic have an average grain size of 50 to 1000 nm, methods for the preparation of the pre-densified and densified ceramics and their use for the manufacture of dental restorations.

First claim

The invention claimed is:

1. Porous CeO 2 -stabilized ZrO 2 ceramic having a density of 50.0 to 95.0%, relative to the theoretical density of zirconia, and an open porosity of 5 to 50%, wherein the pores of the ceramic have a mean pore diameter of 10 to 500 nm.

2. Porous ceramic according to claim 1 having a density of 60.0 to 90.0%.

3. Porous ceramic according to claim 1 having an open porosity of 10 to 30%.

4. Porous ceramic according to claim 1 having a closed porosity of less than 5%.

5. Porous CeO 2 -stabilized ZrO 2 ceramic having a density of 50.0 to 95.0%, relative to the theoretical density of zirconia, and an open porosity of 5 to 50%, wherein grains of the ceramic have an average grain size of 10 to 500 nm.

6. Porous ceramic according to claim 1 comprising tetragonal ZrO 2 in an amount of 50 to 100 vol.-%, based on the total volume of crystals of the ceramic.

7. Porous ceramic according to claim 2 having a density of 70.0 to 85.0%.

8. Porous ceramic according to claim 3 having an open porosity of 14 to 25%.

9. Porous ceramic according to claim 3 having an open porosity of 15 to 23%.

10. Porous ceramic according to claim 4 having a closed porosity of less than 2%.

11. Porous ceramic according to claim 4 having a closed porosity of less than 1%.

12. Porous ceramic according to claim 1 , wherein the pores of the ceramic have a mean pore diameter of 25 to 300 nm.

13. Porous ceramic according to claim 1 , wherein the pores of the ceramic have a mean pore diameter of 50 to 200 nm.

14. Porous ceramic according to claim 5 , wherein the grains of the ceramic have an average grain size of 25 to 300 nm.

15. Porous ceramic according to claim 5 , wherein the grains of the ceramic have an average grain size of 50 to 200 nm.

16. Porous ceramic according to claim 6 comprising tetragonal ZrO 2 in an amount of 70 to 100 vol.-%, based on the total volume of crystals of the ceramic.

17. Porous ceramic according to claim 6 comprising tetragonal ZrO 2 in an amount of 90 to 100 vol.-%, based on the total volume of crystals of the ceramic.

18. Method for preparing a porous CeO 2 -stabilized ZrO 2 ceramic having a density of 50.0 to 95.0%, relative to the theoretical density of zirconia, and an open porosity of 5 to 50%, wherein the pores of the ceramic have a mean pore diameter of 10 to 500 nm comprising
(a) pre-densifying a CeO 2 -containing ZrO 2 starting material to provide the porous ceramic.

19. Method according to claim 18 , wherein pre-densifying in step (a) is performed by spark plasma sintering which includes heating the CeO 2 -containing ZrO 2 starting material to a sintering temperature of about 950 to 1350° C. and/or heating the CeO 2 -containing ZrO 2 starting material at a heating rate of 1 to 400° C./min.

20. Method according to claim 18 , comprising
(b) re-oxidizing the porous ceramic obtained in step (a).

21. Method according to claim 19 , wherein pre-densifying in step (a) is performed by spark plasma sintering the CeO 2 -containing ZrO 2 starting material to a sintering temperature of about 1050 to 1250° C., and/or heating the CeO 2 -containing ZrO 2 starting material at a heating rate of 5 to 100° C./min.

22. Method according to claim 19 , wherein pre-densifying in step (a) is performed heating the CeO 2 -containing ZrO 2 starting material at a heating rate of 50 to 100° C./min.

23. Method of using a porous CeO 2 -stabilized ZrO 2 ceramic having a density of 50.0 to 95.0%, relative to the theoretical density of zirconia, and an open porosity of 5 to 50%, wherein grains of the ceramic have an average grain size of 10 to 500 nm, for the preparation of dental restorations, dental frameworks, dental abutments and dental implants.

Assignees

• Ivoclar Vivadent Ag

Inventors

• Ritzberger Christian
• Rothbrust Frank
• Schweiger Marcel
• Courtois Nicolas
• CHEVALIER Jérôme
• Reveron Helen
• Höland Wolfram
• Rheinberger Volker

Classifications

• A61K6/822

  comprising rare earth metal oxides · CPC title

• A61K6/818

  comprising zirconium oxide · CPC title

• C04B38/0038

  by superficial sintering or bonding of particulate matter · CPC title

• C04B2235/604

  Pressing at temperatures other than sintering temperatures · CPC title

• C04B2235/3201

  Alkali metal oxides or oxide-forming salts thereof · CPC title