Inert dental glass
View Patent ↗The invention relates to the use of ions of weakly basic oxides as linking ions for polyacids in cements, preferably polyelectrolyte cements. Suitable ions comprise elements of the scandium series, for example, Sc 3+ , Y 3+ , La 3+ , Ce 4+ and all subsequent tri- and tetra-valent lanthanides and the ions Mg 2+ , Zn 2+ , Ga 2+ , In 2+ . The application of said ions permits a regulation of the cement reaction without surface treatment of the glass powder.
1. A dental cement comprising a dental glass comprising:
Oxide
Proportion
a member selected from the group
[[30]] 35 to 60%
by
consisting of Y 2 O 3 ,
weight
La 2 O 3 , Gd 2 O 3 , Yb 2 O 3 , and Lu 2 O 3 or
20 to 50%
by weight
Sc 2 O 3 by itself
Al 2 O 3
15 to 40%
by weight
SiO 2
15 to 50%
by weight
P 2 O 5
0 to 2%
by weight
at least one of MgO, CaO, SrO, ZnO, and
0 to 8%
by weight
BaO
at least one of Li 2 O, Na 2 O, K 2 O, Rb 2 O,
0 to 2%
by weight
and Cs 2 O
at least one of TiO 2 , ZrO 2 , and HfO 2
0 to 4%
by weight
at least one of V 2 O 5 , Nb 2 O 5 , and
0 to 4%
by weight
Ta 2 O 5
2. The dental cement of claim 1 , further comprising:
A) mineral solid in an amount of 50 to 90% by weight,
B) water in an amount from 5 to 50% by weight and
C) polyacid in an amount from 5 to 50% by weight, wherein the mineral solid comprises the dental glass.
3. The dental cement as claimed in claim 1 , wherein the dental material comprises a three-component system.
4. The dental cement as claimed in claim 1 , wherein fluorine replaces from 0 to 25% by weight of the oxygen in the dental glass.
5. The dental cement as claimed in claim 1 , wherein the dental glass is in powder form with a specific BET surface area of 1 to 15 m 2 /g.
6. The dental cement as claimed in claim 1 , wherein the dental glass has a mean grain size in a range from 0.01 to 10 μm.
7. The dental cement as claimed in claim 1 , wherein the surface of the dental glass has not been washed with acid, surface coated or conditioned in order to adjust the setting time.
8. The dental cement as claimed in claim 1 , further comprising at least one filler from 0 to 60% by weight in component A).
9. The dental cement as claimed in claim 8 , wherein said at least one filler is selected from the group consisting of quartz, glasses, aluminum oxide, mineral powders, feldspars, kaolin, and plastic powder.
10. The dental cement as claimed in claim 2 , wherein the dental cement has a flexural strength of at least 25 MPa when determined in accordance with ISO 4049.
11. A method of producing a dental cement as described in claim 2 , wherein the surface of the dental glass has not been washed with acid, surface coated, or conditioned, wherein the dental cement is a polyelectrolyte cement and wherein the components of the dental glass are melted to form a dental glass, comprising the step of mixing the mineral solid, water and polyacid to form the dental cement.
12. A process for producing the dental cement according to claim 1 , comprising
reacting a polyacid with weakly basic reacting oxides present in the glass where the glass has not been surface treated.
13. The process as claimed in claim 12 , wherein the dental cement is a polyelectrolyte cement.
14. A vessel, comprising a dental cement, wherein the dental cement comprises a dental glass comprising:
Oxide
Proportion
a member selected from the group consisting of
35 to 60%
by weight
Y 2 O 3 , La 2 O 3 , Gd 2 O 3 , Yb 2 O 3 , and Lu 2 O 3 or
20 to 50%
by weight
Sc 2 O 3 by itself
Al 2 O 3
15 to 40%
by weight
SiO 2
15 to 50%
by weight
P 2 O 5
0 to 2%
by weight
at least one of MgO, CaO, SrO, ZnO, and BaO
0 to 8%
by weight
at least one of Li 2 O, Na 2 O, K 2 O, Rb 2 O, and
0 to 2%
by weight
Cs 2 O
at least one of TiO 2 , ZrO 2 , and HfO 2
0 to 4%
by weight
at least one of V 2 O 5 , Nb 2 O 5 , and Ta 2 O 5
0 to 4%
by weight
and comprising
A) mineral solid in an amount of 50 to 90% by weight,
B) water in an amount from 5 to 50% by weight and
C) polyacid in an amount from 5 to 50% by weight, wherein the mineral solid comprises the dental glass,
and
additional constituents;
wherein the vessel comprises at least two compartments; and
wherein free-flowing constituents are separated from solid constituents.
15. A vessel, comprising a dental cement according to claim 1 , wherein the vessel comprises at least two chambers wherein components capable of flowing are separated from the solid components in the at least two chambers.
16. The vessel as claimed in claim 15 , wherein the vessel is in the form of a mixing capsule.