DENTAL FILLING MATERIAL

• US 20090023115A1
• Filed: 05/12/2008
• Published: 01/22/2009
• Est. Priority Date: 07/20/2007
• Status: Active Grant

• Current Assignee: Coltene/Whaledent AG (Coltene Holding AG)
• Original Assignee: Coltene/Whaledent AG (Coltene Holding AG)
• Inventors: BENZ, Silvan, BOHNER, Ralf, LUBBERS, Dierk
• Granted Patent: US 8,106,109 B2
• Time in Patent Office: Days
• US Class Current: 433/228.100
• CPC Class Codes: A61C 19/003 Apparatus for curing resins by radiation
• CPC Class Codes: A61K 6/54 Filling; Sealing
• CPC Class Codes: A61K 6/858 Calcium sulfates, e.g, gypsum
• CPC Class Codes: A61K 6/887 Compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C08L 33/00 Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides or nitriles thereof; Compositions of derivatives of such polymers
• CPC Class Codes: Y10S 522/908 Dental utility

Abstract

The invention concerns a dental filling material with dual hardening mechanism, wherein i) a first hardening mechanism is based on a photocuring reaction, preferably a radical reaction, and ii) a second hardening mechanism is dependent on H₂O as a reactant, especially as a ligand. Preferably, the second hardening mechanism is a gypsum-type reaction. Owing to the expansion of the composition an excellent marginal seal can be achieved, while the first hardening mechanism allows for a rapid cure on demand.

Claims

1. Dental filling material with dual hardening mechanism, wherein

i) a first hardening mechanism is based on a photocuring reaction, preferably a radical reaction, and

ii) a second hardening mechanism is dependent on H₂O as a reactant, especially as a ligand.

2. Dental filling material according to claim 1, wherein the photocuring reaction is susceptible to initiation by irradiation of blue light, preferably light of a wavelength in the range of about 400 nm to about 500 nm.

3. Dental filling material according to claim 1, comprising acrylate and/or methacrylate resin(s), which are hardenable by photocuring.

4. Dental filling material according to claim 1, further comprising a photoinitiator.

5. Dental filling material according to claim 1, wherein the second hardening mechanism is a gypsum-type reaction.

6. Dental filling material according to claim 1, wherein the second hardening mechanism comprises the addition of crystal water.

7. Dental filling material according to claim 1, wherein the second hardening mechanism comprises

i) the addition of crystal water to water deficient CaSO₄, preferably CaSO₄ with ≦

½

molecules of crystal water, most preferably CaSO₄.½

H₂O;

or

ii) the reaction ZnSO₄.H₂O+ZnO→

Zn₂(OH)₂SO₄ and/or ZnSO₄+ZnO+H₂O→

Zn₂(OH)₂SO₄;

or combinations thereof.

8. Dental filling material according to claim 1, comprising:

a) about 0.1 to about 80 percent, preferably about 15 to about 50 percent by weight of ZnO, and about 0.1 to about 25 percent, preferably about 5 to about 20 percent by weight of ZnSO₄.H₂O and/or ZnSO₄; and

/or

b) about 0.1 to about 80 percent, preferably about 10 to about 60 percent by weight of CaSO₄.½

H₂O;

about 0.001 to about 3 percent, preferably about 0.01 to about 0.5 percent by weight of a photoinitiator;

optionally, up to about 80 percent, preferably about 0.1 to about 50 percent by weight of filling material which is not sensitive to moisture.

9. A method of at least partially hardening a material according to claim 1, comprising the step of irradiating the said material with blue light, preferably light of a wavelength in the range of about 400 nm to about 500 nm.

10. A method of manufacturing of a material according to claim 1, wherein at least

about 1 to about 40 percent, preferably about 5 to about 30 percent by weight of at least one photocurable resin;

a) about 0.1 to about 80 percent, preferably about 15 to about 50 percent by weight of ZnO, and about 0.1 to about 25 percent, preferably about 5 to about 20 percent by weight of ZnSO₄.H₂O and/or ZnSO₄; and

/or

b) about 0.1 to about 80 percent, preferably about 10 to about 60 percent by weight of CaSO₄.½

H₂O;

about 0.001 to about 3 percent, preferably about 0.01 to about 0.5 percent by weight of a photoinitiator;

optionally, up to about 80 percent, preferably about 0.1 to about 50 percent by weight of filling material which is not sensitive to moisture;

are admixed.

11. A method of restoration of a dental cavity or root canal, comprising the steps of

i) applying a dental filling material according to claim into a dental cavity or root canal;

ii) initiating the hardening of the surface layer of the dental filling material by a first hardening mechanism;

iii) allowing the dental filling material below the said surface layer to at least partially set by a second hardening mechanism, preferably via a gypsum-type reaction.

12. A method according to claim 11, wherein initiation of the hardening in step ii) is performed with light, especially with light of a wavelength in the range of about 400 nm to about 500 nm.

13. A method according to claim 11, wherein the opacity of the dental filling material is chosen such as to allow for a selective hardening of about 1 mm of the surface layer by irradiation with an intensity of at least 300 mW/cm² at a wavelength in the range of about 440-480 nm.