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CN-121985928-A - Curable composition for dental use, inorganic powder and method for producing the same

CN121985928ACN 121985928 ACN121985928 ACN 121985928ACN-121985928-A

Abstract

The curable composition for dental use according to the present invention is a composition comprising a polymerizable monomer (M) and a specific inorganic powder (C) composed of aggregated particles (C) comprising inorganic particles (a) and inorganic particles (B), wherein the inorganic particles (a) constitute an inorganic powder (a) having a specific average particle diameter and Zeta potential, the inorganic particles (B) constitute an inorganic powder (B) having a specific average particle diameter and Zeta potential, and the curable composition for dental use further comprises at least 1 selected from the inorganic powder (a) and a specific organic-inorganic composite powder (D), and the content of each powder is within a specific range. According to the present invention, a curable dental composition having high dispersibility of inorganic powder particles in the composition, good pushability from a syringe, moderate fluidity, small change in fluidity with time, and high mechanical strength after curing can be provided.

Inventors

  • FUJIMORI YUJI
  • AKIMOTO KAORI
  • Ji Lianglongtai

Assignees

  • 德山齿科株式会社

Dates

Publication Date
20260505
Application Date
20241031
Priority Date
20231129

Claims (12)

  1. 1. A curable composition for dental use, which comprises a composition containing 100 parts by mass of a polymerizable monomer (M) and 10 to 100 parts by mass of an inorganic powder (C), The inorganic powder (C) is composed of aggregated particles (C) containing inorganic particles (a) and inorganic particles (b), The inorganic particles (a) form an inorganic powder (A), The inorganic powder (A) has a Zeta potential having a negative Zeta potential polarity measured in water, is composed of a plurality of inorganic particles (a) made of the same material as each other, has an average primary particle diameter of 50nm to 1 [ mu ] m measured by an electron microscope, The inorganic particles (B) constitute an inorganic powder (B), The inorganic powder (B) has a Zeta potential having a positive Zeta potential polarity and being composed of a plurality of inorganic particles (B) made of the same material as each other and having an average primary particle diameter of 1 to 300nm as measured by an electron microscope, The average value of the total mass of the inorganic particles (b) is within the range of 20 to 300 parts by mass per 100 parts by mass of the total mass of the inorganic particles (a) contained in the aggregated particles (C) constituting the inorganic powder (C), An inorganic powder (C) having an average agglomerated particle size of 1 to 50 [ mu ] m, defined as the median particle size in the volume-based particle size distribution measured by a laser diffraction/scattering method; The composition further contains at least one of the inorganic powder (A) and the organic-inorganic composite powder (D), The organic-inorganic composite powder (D) is composed of organic-inorganic composite particles (D), wherein the organic-inorganic composite particles (D) comprise a composite material of the inorganic powder (A) and a resin, the content of the inorganic powder (A) in the composite material is 60-90% by mass, and the average particle diameter of the organic-inorganic composite powder (D) is 1-100 [ mu ] m as defined by the median particle diameter in the particle size distribution of the volume standard measured by a laser diffraction scattering method; in the composition, the total content of the inorganic powder (A) independent of the containing form is 170-270 parts by mass, and the total content of the inorganic powder (B) independent of the containing form is 5-50 parts by mass.
  2. 2. The curable composition for dental use according to claim 1, wherein the inorganic particles (b) are uniformly dispersed in the inorganic particles (a) among the respective aggregated particles (C) constituting the inorganic powder (C).
  3. 3. The curable composition for dental use according to claim 1, wherein the inorganic particles (a) comprise a silica-based inorganic compound and the inorganic particles (b) comprise a crystalline rare earth metal fluoride.
  4. 4. The curable composition for dental use according to claim 3, wherein the full width at half maximum of the maximum intensity peak derived from the crystalline rare earth metal fluoride in an X-ray diffraction pattern obtained by X-ray diffraction measurement of the inorganic powder (B) is 0.3 ° or more.
  5. 5. The curable composition for dental use according to claim 1, wherein the inorganic powder (C) is obtained by spray-drying a uniform mixed slurry obtained by mixing 100 parts by mass of the slurry (Sa) in which the inorganic powder (a) is dispersed in a dispersion medium and 20 to 300 parts by mass of the slurry (Sb) in which the inorganic powder (B) is dispersed in a dispersion medium.
  6. 6. A method for producing a curable composition for dental use according to claim 1, which comprises mixing the polymerizable monomer (M) and the inorganic powder (C) with at least one of the inorganic powder (A) and the organic-inorganic composite powder (D).
  7. 7. The method for producing a curable composition for dental use according to claim 6, wherein, The inorganic powder (C) is produced by mixing a slurry (Sa) in which 100 parts by mass of the inorganic powder (A) is dispersed in a dispersion medium with a slurry (Sb) in which 20 to 300 parts by mass of the inorganic powder (B) is dispersed in a dispersion medium to obtain a uniform mixed slurry, and spray-drying the mixed slurry.
  8. 8. The method for producing a curable composition for dental use according to claim 7, wherein the mixed slurry does not contain an ionic surfactant.
  9. 9. The method for producing a curable composition for dental use according to claim 7, wherein the concentration of the mixed slurry is less than 40 mass%.
  10. 10. An inorganic powder (C) comprising aggregated particles (C) containing inorganic particles (a) and inorganic particles (b), The inorganic particles (a) form an inorganic powder (A), The inorganic powder (A) has a Zeta potential having a negative Zeta potential polarity measured in water, is composed of a plurality of inorganic particles (a) made of the same material as each other, has an average primary particle diameter of 50nm to 1 [ mu ] m measured by an electron microscope, The inorganic particles (B) constitute an inorganic powder (B), The inorganic powder (B) has a Zeta potential having a positive Zeta potential polarity and being composed of a plurality of inorganic particles (B) made of the same material as each other and having an average primary particle diameter of 1 to 300nm as measured by an electron microscope; the average value of the total mass of the inorganic particles (b) is in the range of 20 to 300 parts by mass per 100 parts by mass of the total mass of the inorganic particles (a) contained in each of the aggregated particles (C) constituting the inorganic powder particle (C); the inorganic powder has an average agglomerated particle size defined as the median particle size in the volume-based particle size distribution measured by a laser diffraction scattering method of 1 to 50 [ mu ] m, The inorganic powder does not contain an ionic surfactant.
  11. 11. A method for producing an inorganic powder according to claim 10, comprising the steps of mixing a slurry (Sa) in which 100 parts by mass of the inorganic powder (A) is dispersed in a dispersion medium with a slurry (Sb) in which 20 to 300 parts by mass of the inorganic powder (B) is dispersed in a dispersion medium to obtain a uniform mixed slurry, and spray-drying the mixed slurry; The mixed slurry does not contain an ionic surfactant.
  12. 12. A method for producing an inorganic powder or granule according to claim 11, wherein the concentration of the mixed slurry is less than 40% by mass.

Description

Curable composition for dental use, inorganic powder and method for producing the same Technical Field The present invention relates to a curable composition for dental use, an inorganic powder and a method for producing the same. Background The curable composition for dental use contains a polymerizable monomer (monomer), an inorganic filler (filler) containing an aggregate of inorganic particles (inorganic powder) and a polymerization initiator as main components, and the composite resin is one of the most used materials for dental treatment as a material for repairing defects of teeth and removing cavities after caries. As the composite resin, there is a demand for excellent various physical properties such as handleability in a paste state before polymerization curing, aesthetic properties of a cured product obtained after polymerization curing, and mechanical strength. In recent years, a needle having a small hole called a tip (NEEDLE TIP) has been attached to a syringe containing a composite resin paste, and a flowable composite resin designed to allow paste to be directly filled into a cavity from the tip of the needle has been developed, so that dental restoration can be performed more easily, and thus, the syringe has been used more in clinical sites. In the above-mentioned flowable composite resin, there is a demand for good handling properties such as filling into a cavity, specifically, good pushability when pushing out from a syringe to which a tip is attached, and proper fluidity in a paste state according to a case or the like. For example, if fluidity is too high in a paste state, the paste tends to drop easily, and formability (i.e., the property of being difficult to deform by natural flow and maintain shape when left standing) is deteriorated, so that proper fluidity is required. The fluidity composite resin has a relatively small content of inorganic powder particles, and thus has improved fluidity and improved pushout from a syringe, but it may be difficult to obtain formability due to the high fluidity. In order to solve such problems, patent document 1 discloses a technique of using 2 kinds of inorganic powder particles having a specific average particle diameter and specific surface area in a specific quantitative ratio together, which have Zeta potentials (in water) with opposite polarities, thereby improving the physical properties of the composite resin. In addition, in examples thereof, a curable composition for dental use comprising a polymerizable monomer, a silica-based composite oxide having an average particle diameter of 50nm to 1 μm, and a crystalline rare earth metal fluoride having a specific surface area of 25 to 100m 2/g is described, which has excellent pushability (a consistency suitable for pushing from a syringe) and shows moderate fluidity for suppressing sagging of paste or the like. Prior art literature Patent literature Patent document 1 International publication No. 2023/085201 pamphlet Disclosure of Invention Problems to be solved by the invention As described above, patent document 1 discloses that a curable composition (paste) for dental use having appropriate fluidity can be obtained by using a silica-based composite oxide and a crystalline rare earth metal fluoride having mutually different polarities of Zeta potential in combination. However, patent document 1 does not study the change in the fluidity of the curable composition for dental use with time. As is clear from the study by the present inventors, the dental curable composition described in patent document 1 may have a high fluidity and may not exhibit proper fluidity when stored for a long period of time (for example, about 1 week at 50 ℃). Accordingly, an object of the present invention is to provide a curable composition for dental use, which has high dispersibility of inorganic powder particles, good pushability from a syringe, moderate fluidity, little change in fluidity with time, and high mechanical strength after curing. Another object of the present invention is to provide an inorganic powder having good dispersibility when incorporated in a curable composition for dental use, and a method for producing the same. Means for solving the problems The present inventors have repeatedly conducted intensive studies in order to achieve the above object. As a result, it has been found that the above-described problems can be solved by a curable composition for dental use, and the present invention has been completed. The curable composition for dental use comprises a polymerizable monomer (M) and a specific inorganic powder (C) composed of aggregated particles (C) comprising inorganic particles (a) constituting an inorganic powder (A) having a specific average particle diameter and a Zeta potential and inorganic particles (B) constituting an inorganic powder (B) having a specific average particle diameter and a Zeta potential, wherein the composition further comprises at least 1 selected from the