Method to produce a dental structure and dental structure

Patent metadata

Field	Value
Publication number	US-2016340240-A1
Application number	US-201615159427-A
Country	US
Kind code	A1
Filing date	May 19, 2016
Priority date	May 22, 2015
Publication date	Nov 24, 2016
Grant date	—

Abstract

The invention relates to a method to produce a dental structure with a cavity having a negative form of the structure, which is formed in an investment material, wherein flowable lithium silicate glass ceramic is pressed into the cavity. Thereby a compressive surface stress is created in the ceramic structure through the replacement of lithium ions by alkali ions, in that the model is enriched with alkali compounds and/or the model is covered with a layer of a material containing alkali ions.

First claim

1 . A method to produce a dental structure comprising the steps of:
providing a cavity that has a negative shape of the structure, which is formed in an investment material using a model which prescribes the shape of the cavity and can be removed, wherein the model is enriched with one or more alkali compounds having alkali ions and/or the model is covered with a layer of material having alkali ions; pressing lithium silicate glass ceramic into the cavity to form a ceramic structure; and creating a surface compressive stress in the ceramic structure through the replacement of lithium ions by alkali ions of a greater diameter.

2 . The method according to claim 1 , further comprising the step of forming the layer with which the model is covered with the material having potassium ions and at least one salt selected from the group consisting of inorganic acids, organic acids or a combination of both.

3 . The method according to claim 2 , wherein the inorganic acids and/or the organic acids are selected from the group consisting of nitrates, carbonates, acetates and chlorides.

4 . The method according to claim 1 , wherein the one or more alkali compounds are in the form of one or more salts of inorganic acids and/or organic acids.

5 . The method according to claim 4 , wherein the one or more salts of inorganic acids and/or organic acids are selected from the group consisting of nitrates, carbonates, acetates and chlorides.

6 . The method according to claim 1 , further comprising the step of applying the layer having a thickness D where 10 μm≦D≦100 μm.

7 . The method according to claim 1 , wherein the percentage by weight of the alkali ions in the model or in the layer covering the model is in the range 0.5-10% by weight.

8 . The method according to claim 1 , wherein the lithium silicate glass ceramic is produced from a glass melt that includes as starting components at least SiO 2 , Al 2 O 3 , Li 2 O, K 2 O, at least one nucleating agent, at least one stabilizer, and at least one coloring metal oxide.

9 . The method of claim 8 , wherein the at least one nucleating agent is P 2 O 5 , the at least one stabilizer is ZrO 2 , and the at least one coloring metal oxide is CeO 2 and/or Tb 4 O 7 .

10 . The method according to claim 8 , wherein the glass melt includes the following starting components in percentage by weight:

SiO 2
50-80,

at least one nucleating agent
0.5-11, 

Al 2 O 3
 0-10,

Li 2 O
10-25,

K 2 O
 0-13,

Na 2 O
0-1,

ZrO 2
 0-20,

CeO 2
 0-10,

Tb 4 O 7
0-8,

optionally an oxide or a number of oxides of an earth alkali metal or a number of earth alkali metals from the group magnesium, calcium, strontium, barium 0-20,
optionally one or more additives selected from the group consisting of B 2 O 3 , MnO 2 , Fe 2 O 3 , V 2 O 5 , TiO 2 , Sb 2 O 3 , ZnO, SnO 2 and fluorides 0-6,
optionally one or more oxides of the rare earth metals with the atomic numbers 57, 59-64, 66-71, 0-5,
wherein the total sum is 100% by weight.

11 . The method according to claim 8 , wherein the glass melt includes the following starting components in percentage by weight:

SiO 2
  52-70,

at least one nucleating agent
  3-8,

Al 2 O 3
0.5-5,

Li 2 O
  13-22,

K 2 O
0.5-8,

Na 2 O
   0-0.5,

ZrO 2
  4-16,

CeO 2
0.5-8,

Tb 4 O 7
0.5-6,

optionally an oxide or a number of oxides of an earth alkali metal or a number of earth alkali metals from the group magnesium, calcium, strontium, barium 0-20,
optionally one or more additives selected from the group consisting of B 2 O 3 , MnO 2 , Fe 2 O 3 , V 2 O 5 , TiO 2 , Sb 2 O 3 , ZnO, SnO 2 and fluorides 0-6,
optionally one or more oxides of the rare earth metals with the atomic numbers 57, 59-64, 66-71, 0-5,
wherein the total sum is 100% by weight.

12 . The method according to claim 8 , wherein the glass melt includes as starting components in percentage by weight the following:

SiO 2
58.1 ± 2.0

P 2 O 5
 5.0 ± 1.5

Al 2 O 3
 4.0 ± 2.5

Li 2 O
16.5 ± 4.0

K 2 O
 2.0 ± 0.2

ZrO 2
10.0 ± 0.5

CeO 2
0-3,

Tb 4 O 7
0-3,

Na 2 O
  0-0.5,

Assignees

• Dentsply Sirona Inc

Inventors

• Vollmann Markus
• Schusser Udo

Classifications

• A61K6/833

  Glass-ceramic composites · CPC title

• A61K6/818

  comprising zirconium oxide · CPC title

• A61K6/853

  Silicates · CPC title

• A61K6/822 Primary

  comprising rare earth metal oxides · CPC title

• A61C5/77

  Methods or devices for making crowns · CPC title