Production of dental shaped parts

Patent metadata

Field	Value
Publication number	US-10646309-B2
Application number	US-201715652635-A
Country	US
Kind code	B2
Filing date	Jul 18, 2017
Priority date	Dec 17, 2010
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

From the obtained blank, monolithic dental shaped parts can be obtained by mechanical processing followed by sintering, wherein a process according to the invention for stabilizing the shape of the shaped parts is used.

First claim

The invention claimed is:

1. A process for producing a sintered monolithic dental shaped part
comprising at least one sintering step in which a monolithic shaped part is sintered, wherein the monolithic shaped part is connected to at least one support structure or to at least one support mould during at least one time segment within the duration of the sintering, such that during the at least one time segment the monolithic shaped part has a change in shape that is limited by the support structure or the support mould, and
further comprising releasing the monolithic shaped part from the at least one support structure or the at least one support mould after the at least one sintering step.

2. The process according to claim 1 , wherein said at least one time segment is provided at least at the end of the duration of the sintering.

3. The process according to claim 1 , wherein the support structure or the support mould comprises a temperature-resistant material the shape of which changes during the sintering by less than 2 vol.-%.

4. The process according to claim 1 , wherein the support structure or the support mould comprises a temperature-resistant material the shape of which changes during the sintering by less than 1 vol.-%.

5. The process according to claim 1 , wherein the support structure or the support mould comprises a material having a sintering shrinkage that corresponds to the sintering shrinkage of the monolithic dental shaped part during the sintering.

6. The process according to claim 1 , wherein the process further comprises machining a blank consisting entirely of porous glass without crystalline portions and having a density between 50% and 95% of the theoretical density of the blank when it is in a densely-sintered state and having a disc-like shape with a diameter of at least 20 mm to obtain a monolithic shaped part, and wherein the at least one sintering step comprises sintering the thus-obtained monolithic shaped part to at least 98% of theoretical density.

7. The process according to claim 6 , wherein the density of the blank is between 55% and 85% of the theoretical density.

8. The process according to claim 7 , wherein the density of the blank is between 70% and 80% of the theoretical density.

9. The process according to claim 6 , wherein the porous glass comprises the following components:

SiO 2
50-80 wt.-%

Al 2 O 3
 3-24 wt.-%

K 2 O
 3-13 wt.-%

Na 2 O
 3-13 wt.-%

Li 2 O
 0-4 wt.-%

B 2 O 3
 0-4 wt.-%

F
 0-4 wt.-%

TiO 2
 0-8 wt.-%

ZrO 2
 0-8 wt.-%

P 2 O 5
 0-4 wt.-%

SnO 2
 0-4 wt.-%

MgO
 0-4 wt.-%

CaO
 0-4 wt.-%

BaO
 0-4 wt.-%

Sb 2 O 3
 0-4 wt.-%

CeO 2
 0-8 wt.-%.

10. The process according to claim 9 , wherein the porous glass comprises the following components:

SiO 2
55-65 wt.-%

Al 2 O 3
17-24 wt.-%

K 2 O
 5-9 wt.-%

Na 2 O
 7-11 wt.-%

Li 2 O
 0-1 wt.-%

B 2 O 3
 0-2 wt.-%

F
 0-1 wt.-%

TiO 2
 0-1 wt.-%

ZrO 2
 0-2 wt.-%

P 2 O 5
 0-1 wt.-%

SnO 2
 0-1 wt.-%.

11. The process according to claim 9 , wherein the porous glass comprises the following components:

SiO 2
55-80 wt.-%

Al 2 O 3
 7-23 wt.-%

K 2 O
 3-10 wt.-%

Na 2 O
 3-13 wt.-%

Li 2 O
 0-1 wt.-%

B 2 O 3
 0-4 wt.-%

F
 0-1 wt.-%

TiO 2
 0-1 wt.-%

ZrO 2
 0-8 wt.-%

P 2 O 5
 0-1 wt.-%.

Assignees

• Ivoclar Vivadent Ag

Inventors

• Reinshagen Jörg
• Cramer Von Clausbruch Sascha
• Winterling Michael

Classifications

• A61C13/0022 Primary

  Blanks or green, unfinished dental restoration parts · CPC title

• C03C11/00 Primary

  Multi-cellular glass {; Porous or hollow glass or glass particles} · CPC title

• Y10T428/21

  Circular sheet or circular blank · CPC title

• A61K6/836 Primary

  Glass · CPC title

• C03C4/0021

  for dental use · CPC title