POROUS, SILICATE, CERAMIC BODY, DENTAL RESTORATIONS AND METHOD FOR THE PRODUCTION THEREOF

• US 20110183297A1
• Filed: 07/21/2009
• Published: 07/28/2011
• Est. Priority Date: 07/21/2008
• Status: Abandoned Application

• Current Assignee: Vita Zahnfabrik H. Rauter GMBH & Co.. KG (Rauter Beteiligungsgesellschaft mbH)
• Original Assignee: Vita Zahnfabrik H. Rauter GMBH & Co.. KG (Rauter Beteiligungsgesellschaft mbH)
• Inventors: Tholey, Michael, Bibus, Joachim, Bojemüller, Enno, Dorn, Michael, Thiel, Nobert, Geske, Vilma, Huber, Birgit
• Application Number:
  US12/737,491
• Publication Number:
  US 20110183297A1
• Time in Patent Office: Days
• US Class Current: 433/217.1
• CPC Class Codes: A61C 13/0003 Making bridge-work, inlays, implants or the like
• CPC Class Codes: A61C 13/0022 Blanks or green, unfinished dental restoration parts
• CPC Class Codes: A61C 13/083 Porcelain or ceramic teeth A61C13/081 takes precedence; preparations A61K6/80
• CPC Class Codes: A61C 13/20 Methods or devices for soldering, casting, moulding or melting A61C13/04, A61C13/081 take precedence
• CPC Class Codes: C04B 2111/00836 for medical or dental applications
• CPC Class Codes: C04B 2235/6022 Injection moulding
• CPC Class Codes: C04B 2235/6026 Computer aided shaping, e.g. rapid prototyping
• CPC Class Codes: C04B 2235/656 characterised by specific heating conditions during heat treatment
• CPC Class Codes: C04B 2235/6562 Heating rate
• CPC Class Codes: C04B 2235/6567 Treatment time
• CPC Class Codes: C04B 2235/6581 Total pressure below 1 atmosphere, e.g. vacuum
• CPC Class Codes: C04B 2235/661 Multi-step sintering
• CPC Class Codes: C04B 2235/77 Density
• CPC Class Codes: C04B 2235/96 Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
• CPC Class Codes: C04B 2235/9607 Thermal properties, e.g. thermal expansion coefficient
• CPC Class Codes: C04B 2235/9615 Linear firing shrinkage
• CPC Class Codes: C04B 2235/9661 Colour
• CPC Class Codes: C04B 35/16 based on silicates other than clay zircon C04B35/48
• CPC Class Codes: C04B 35/64 Burning or sintering processes C04B33/32 takes precedence ; powder metallurgy B22F
• CPC Class Codes: C04B 38/00 Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof treating slag with gases or gas generating material C04B5/06 ; expanded graphite C04B35/536
• CPC Class Codes: C04B 38/0054 : the pores being microsized or nanosized

Abstract

The present invention relates to a porous, silicate, ceramic body, possibly with different colors, with a first density, which can be sintered into a silicate, ceramic body with a second density, wherein the ratio of the first density to the second density is 2/5 to 98/100, and the three-point bending strength of the porous, silicate ceramic body with a first density, measured according to ISO 6872, amounts to 25 to 180 MPa.

Claims

1. A porous silicate-ceramic body, optionally with different colors, having a first density that can be sintered to a silicate-ceramic body having a second density, wherein the ratio of the first density to the second density is from 2/5 to 98/100, and the three-point bending strength of said porous silicate-ceramic body having a first density as measured according to ISO 6872 is from 25 to 180 MPa.

2. The porous silicate-ceramic body according to claim 1, the second density approximately corresponds to the theoretically reachable density of the ceramic body.

3. The porous silicate-ceramic body according to claim 1, wherein the coefficient of thermal expansion (CTE) of the body is adjusted for use as a veneer material for a scaffold and, as measured according to ISO 6872, is at least 7×

10<sup>−

6</sup> K<sup>−

1</sup>.

4. The porous silicate-ceramic body according to claim 3, wherein the CTE of the body as measured according to ISO 6872 is from 7 to 16×

10<sup>−

6</sup> K<sup>−

1</sup>.

5. The porous silicate-ceramic body according to claim 3, wherein the CTE of the body as measured according to ISO 6872 is from 7 to 10×

10<sup>−

6</sup> K<sup>−

1</sup>.

6. The porous silicate-ceramic body according to claim 1, designed as a molded member.

7. The porous silicate-ceramic body according to claim 6, comprising a holding element.

8. The porous silicate-ceramic body according to claim 6, embedded in a matrix.

9. A dental restoration precursor obtainable by processing a porous silicate-ceramic body according to claim 1.

10. A dental restoration obtainable by dense-sintering the dental restoration precursor according to claim 9, a sintering shrinkage being taken into account if necessary.

11. A dental restoration precursor obtainable by processing the porous silicate-ceramic body according to claim 1 and applying it to a complementary scaffold.

12. A dental restoration obtainable by dense-sintering the dental restoration precursor according to claim 11, a sintering shrinkage being taken into account if necessary, onto the complementary scaffold.

13. In a process comprising sintering a porous silicate-ceramic body to produce a dental restoration, the improvement comprising use of the porous silicate-ceramic body according to claim 1.

14. A process for preparing the porous silicate-ceramic body according to claim 1, comprising the steps of:

preparing a green body having the desired geometry;

if necessary, removing the binder from the green body to obtain a preform, optionally under vacuum;

sintering the preform to obtain a porous molded member, optionally under vacuum.

15. A process for preparing a dental restoration, comprising the steps of:

processing the porous silicate-ceramic body according to claim 1 to produce a veneer;

positioning the veneer on a scaffold and subjecting it to sinter firing;

dense-sintering the restoration precursor into the final dental restoration; and

dense-sintering the veneer followed by positioning and bonding (by sintering, adhesive bonding, using a glass solder) to a scaffold.

16. The porous silicate-ceramic body of claim 3, wherein the CTE is from 7 to 18×

10<sup>−

6</sup> K<sup>−

1</sup>.

17. The porous silicate-ceramic body of claim 4, wherein the CTE is from 12 to 15×

10<sup>−

6</sup> K<sup>−

1</sup>.