Dental curable composition

• US 20030036582A1
• Filed: 04/22/2002
• Published: 02/20/2003
• Est. Priority Date: 08/22/2000
• Status: Active Grant

• Current Assignee: Tokuyama Corporation
• Original Assignee: Tokuyama Corporation
• Inventors: Kazama, Hideki, Yamakawa, Junichiro
• Granted Patent: US 6,933,327 B2
• Time in Patent Office: Days
• US Class Current: 523/115
• CPC Class Codes: A61K 6/71 Fillers
• 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

Abstract

A dental polymerizable and curable composition that can be used as a dental composite restorative featuring excellent handling property at the time of filling, a small contraction upon polymerization, a high bending strength, excellent surface smoothness and wear resistance, and a very good matching of color tone to the natural tooth after restored.

Claims

1. A dental curable composition containing an organic/inorganic composite filler having an average particle diameter of from 1 to 20 μ

m and a polymerizable monomer, wherein a cured product of said dental curable composition has a diffusion degree D as defined by the following formula,

D={(I₂₀/cos 20°

)+(I₇₀/cos 70°

)}/(2×

I₀)

wherein I₀, I₂₀ and I₇₀ denote intensities of light that has passed through in the directions of 0°

, 20° and

70°

with respect to the direction of incidence of light when light is permitted to fall perpendicularly onto the surface of a plate-like sample having a thickness of 0.3 mm obtained by curing said dental curable composition, of not smaller than 0.01.

2. A dental curable composition according to claim 1, wherein the diffusion degree D is not smaller than 0.01 but is not larger than 0.5.

3. A method of producing a dental curable composition according to claim 1, wherein, in producing the dental curable composition by mixing a polymerizable monomer composition and an organic/inorganic composite filler having an average particle diameter of from 1 to 20 μ

m together, a refractive index of said organic/inorganic composite filler and a refractive index of the cured product obtained by curing said polymerizable monomer composition, are so adjusted that a difference therebetween is not smaller than, 0.01 in an absolute value.

4. A method of producing a dental curable composition according to claim 3, wherein a refractive index of said organic/inorganic composite filler and a refractive index of the cured product obtained by curing said polymerizable monomer composition, are so adjusted that a difference therebetween is not smaller than 0.01 but is not larger than 0.04 in an absolute value.

7. A dental curable composition according to any one of claims 1, 2, 5 and 6, wherein the organic/inorganic composite filler is the one obtained by pulverizing the cured product of the polymerizable and curable composition that contains a polymerizable monomer and spherical or nearly spherical inorganic particles having an average particle diameter of from 0.001 to 1 μ

m and/or aggregates of said inorganic particles.

8. A dental curable composition according to claim 7, wherein the inorganic particles and/or the aggregates of said inorganic particles contained in the organic/inorganic composite filler, are chiefly constituted by an inorganic oxide obtained by reacting an organosilicon compound which is hydrolyzable and an organic compound of at least one kind of metal selected from the group consisting of metals of the Groups I, II, III and IV of periodic table which can be bonded to the organosilicon compound which is hydrolyzable.

9. A dental curable composition according to any one of claims 1, 2, 5, 6, 7 and 8, wherein there is contained the inorganic filler which comprises spherical or nearly spherical inorganic particles having an average particle diameter of not larger than 1 μ

m and/or aggregates of said inorganic particles.

10. A dental curable composition according to claim 9, wherein the inorganic filler is treated for its surfaces with a silane compound represented by the following general formula,

CH₂═ C(R¹)—

COO—

(CH₂)_n—

Si—

R²_mR³_(3-m) 

 

[I]

wherein R¹ is a hydrogen atom or a methyl group, R² is an alkoxy group having 1 to 6 carbon atoms, an isocyanate group or a chlorine atom, R³ is a hydrocarbon group having 1 to 6 carbon atoms, m is 2 or 3, and n is an integer of 8 to 20.

11. A dental curable composition according to any one of claims 1, 2, 5, 6, 7, 8, 9 and 10, wherein the organic/inorganic composite filler contains a fluorescent whitening agent.

12. A dental curable composition according to claim 11, wherein the cured product has a yellowness index (YI) as defined by the following formula,

Yellowness ivdex (YI)=100×

(1.28X−

1.06Z)/Y

wherein X, Y and Z are three stimulus values of when a sample having a thickness of 2 mm is measured using a color-difference meter with the sample being closely adhered to a white background, of not larger than 20.

13. A dental curable composition according to any one of claims 1, 2, 5, 6, 7, 8, 9, 10, 11 and 12, wherein the polymerizable monomer constituting the dental curable composition forms a cured product thereof having a refractive index which is different in an absolute value by from 0.005 to 0.05 from the refractive index of the cured product of the polymerizable composition used as the starting material of the organic/inorganic composite filler.

5. A dental curable composition containing an organic/inorganic composite filler and a polymerizable monomer, the organic/inorganic composite filler satisfying the following conditions (1) and (2):

(1) an average particle diameter is from 1 to 20 μ

m; and

(2) when a refractive index thereof is denoted by n_F and a refractive index of a matrix portion in which saidorganic/inorganic composite filler is dispersed in a cured product obtained by curing said dental curable composition, is denoted by n_M, then, an absolute value of n_F−

n_M is not smaller than 0.01.

6. A dental curable composition according to claim 5, wherein under the condition (2) of the organic/inorganic composite filler, the absolute value of n_F−

n_M is not smaller than 0.01 but is not larger than 0.04.