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RU-2861668-C2 - DENTAL CURABLE COMPOSITION, DENTAL BLANK FOR MACHINING, METHOD FOR PRODUCING COMPLEX SILICON OXIDE IN FORM OF PARTICLES AND FILLING MATERIAL

RU2861668C2RU 2861668 C2RU2861668 C2RU 2861668C2RU-2861668-C2

Abstract

FIELD: dentistry. SUBSTANCE: group of inventions relates to a method for producing a complex silicon oxide in the form of particles, the use of a dental filler comprising said particles, as well as a dental curable composition and a dental blank for machining containing said complex silicon oxide. The proposed method for producing a complex silicon oxide in the form of primary particles, where the complex silicon oxide comprises a complex silicon-titanium or silicon-zirconium oxide, has a relative silicon dioxide content of 80-92 mol.%, wherein 100 mol.% is the total amount of the complex oxide, has an average primary particle size of 350-600 nm and is formed from spherical particles that do not include a silicon dioxide core, is carried out by using a specific composition and ratio of organic solvents in all solutions used at each stage of obtaining the complex silicon oxide. Also proposed are: the use of a dental filler comprising a complex silicon oxide in the form of particles, which comprises a complex silicon-zirconium oxide with the above characteristics, for producing a dental curable composition; a dental curable composition comprising a radically polymerisable monomer and the above complex silicon-zirconium oxide in the form of particles; a dental blank for machining comprising a machined part including a cured material of the above dental curable composition. EFFECT: cured material that does not cause colour distortion depending on thickness. 11 cl, 5 tbl, 21 ex

Inventors

  • OYA, NAOYUKI
  • MORISAKI, HIROSHI

Dates

Publication Date
20260507
Application Date
20230809
Priority Date
20220927

Claims (20)

  1. 1. A method for producing complex silicon oxide in the form of primary particles, comprising:
  2. a step of obtaining a solution of the starting material by dissolving the condensable silicon compound and the condensable metal compound in a first solvent comprising a first organic solvent; and
  3. a step of precipitating a complex silicon oxide in the form of primary particles by adding a solution of a starting material to a base solution comprising a second solvent that comprises a second organic solvent and water, to hydrolyze and condense a condensable silicon compound and a condensable metal compound, wherein the complex silicon oxide in the form of primary particles comprises a complex oxide of silicon, titanium or zirconium, has a relative silicon dioxide content of 80-92 mol.%, wherein 100 mol.% constitutes the total amount of the complex oxide, and is formed from a spherical particle, characterized in that:
  4. in the first organic solvent, the relative content of methanol is 80% by weight or more,
  5. in the second organic solvent, the total relative content of an alcohol having an alkyl group that contains 3 carbon atoms and/or an alcohol having an alkyl group that contains 4-5 carbon atoms is 80 mass% or more, and the relative content of an alcohol having an alkyl group that contains 3 or less carbon atoms is 5-25 mass%, and
  6. A complex silicon oxide in the form of primary particles, which has an average primary particle size of 350-600 nm and does not include a silicon dioxide core inside a spherical particle, is precipitated by adding a solution of a raw material to a basic solution such that the relative content of an alcohol having an alkyl group that contains 3-5 carbon atoms is 65 mass% or more relative to the total mass of the first organic solvent and the second organic solvent.
  7. 2. A method for producing a complex silicon oxide in the form of particles according to claim 1, characterized in that the complex silicon oxide in the form of particles additionally includes at least one metal selected from a metal of group 2 of the Periodic Table, a metal of group 13 of the Periodic Table, and an alkali metal.
  8. 3. A method for producing complex silicon oxide in the form of particles according to paragraph 1, characterized in that
  9. the stage of obtaining a solution of the starting material includes:
  10. a step of obtaining, by mixing silicon alkoxide, methanol, water and an acid, a first composition in which a partial hydrolysate of silicon alkoxide and/or an oligomer obtained by condensation of the partial hydrolysate are dissolved, a step of obtaining, by mixing a metal alkoxide and a polar organic solvent for dissolving the metal alkoxide, a second composition in which at least one of the metal alkoxide, the partial hydrolysate of the metal alkoxide or the oligomer obtained by condensation of the partial hydrolysate is dissolved, and
  11. a step of obtaining a solution of the starting material by mixing the first composition and the second composition.
  12. 4. A method for producing complex silicon oxide in the form of particles according to paragraphs 1, 2 or 3, characterized in that the value of the standard deviation of the average size of the primary particles is in the range of 1.00-1.30.
  13. 5. The use of a dental filler for producing a dental curable composition, wherein the dental filler is mixed with a dental curable composition that includes a radically polymerizable monomer,
  14. wherein the dental filler comprises a complex oxide of silicon and zirconium, has a relative silicon dioxide content of 80-92 mol.%, wherein 100 mol.% constitutes the total amount of the complex oxide, and an average primary particle size of 350-600 nm and is a complex silicon oxide in the form of particles formed from a spherical particle that does not include a silicon dioxide core inside, the value of the standard deviation of the average primary particle size being in the range of 1.00-1.30, wherein the dental filler satisfies the following formula:
  15. 0.01<n F -n P <0.1,
  16. where n F is the refractive index of the spherical particle at 25°C and with respect to light of wavelength 589 nm, and n P is the refractive index of the cured radical polymerizable monomer material at 25°C and with respect to light of wavelength 589 nm.
  17. 6. The use of a dental filler according to claim 5, wherein the dental filler further comprises at least one metal selected from a metal of group 2 of the Periodic Table, a metal of group 13 of the Periodic Table, and an alkali metal.
  18. 7. A dental curable composition comprising:
  19. radically polymerizable monomer: 100 parts by weight; and
  20. a particulate composite silicon oxide that includes composite silicon oxide and zirconium oxide, has a relative silicon dioxide content of 80-92 mol%, of which 100 mol% is the total amount of composite oxide, and an average primary particle size of 350-600 nm, and is formed from a spherical particle not including a silicon dioxide core: 100-800 parts by weight, and satisfies the following formula:

Description

Field of technology to which the invention relates [0001] The present invention relates to a dental curable composition, a dental blank for turning, a complex silicon oxide in the form of particles and a filling material. State of the art [0002] The composite resin used in dental filling (hereinafter abbreviated as "CR" in some cases) is a dental curable composition that produces a cured material called a hybrid resin (hereinafter abbreviated as "HR" in some cases). In addition, HR is also widely used as a material for inlays, onlays, crowns, bridges, implant abutments, etc. used in dental prosthetics. [0003] A dental curable composition, which is a raw material of a GS, is often composed of a composition including an inorganic filler such as silica, a polymerizable monomer such as a methacrylate resin, and a polymerization initiator from the viewpoint of strength, etc. As the inorganic filler, a particulate material (particulate inorganic material) formed of spherical particles of an inorganic oxide is often used from the viewpoint of machinability and polishing and high aesthetic properties (see Patent Literature 1). In addition, as a filler, which is spherical particles of an inorganic oxide, particles formed from spherical particles of complex silicon oxide are usually used, which is an inorganic oxide that includes as main components at least one metal selected from the group consisting of Groups I to IV of the Periodic Table and a silicon component, in particular, a complex oxide of silicon-element of Group 4, such as silicon-zirconium oxide (see Patent Literatures 1-3). [0004] It should be noted that, in general, it is considered that a particulate material formed from spherical particles of complex silicon oxide is produced by a so-called sol-gel method in which a hydrolyzable (condensable) compound such as silicon and various metal alkoxides is subjected to hydrolysis and dehydration condensation in a basic aqueous solution, wherein in the above-mentioned sol-gel method, when a core (a seed or a center for grain growth) of silicon dioxide is formed by adding only a raw silicon compound to a basic aqueous solution, and then a mixture of the raw silicon compound and the raw metal oxide compound is added to grow a layer of complex oxide around the core of silicon dioxide, a suitable distribution of the sizes of the obtained particles can be obtained (particles formed from spherical particles of the same diameter can be obtained) (Patent Literature 3). In addition, particles formed from spherical particles of complex silicon oxide of group 4 element, which are used as a dental filler, are often obtained in this way (see, for example, Production Examples 5 and 6 from Patent Source 2). [0005] As a dental blank for turning, which has become increasingly popular in recent years with the progress of digital technology, there is known a hybrid resin dental blank for turning (hereinafter, the hybrid resin dental blank will also be simply referred to as a "HS blank" for short), including a turning part formed of HS in which the above-described Group 4 element complex oxide particles are mixed (see Patent Literature 4). It should be noted that the dental blank for turning means a specialized blank (also called a milling blank) that can be mounted on a cutting machine of a cutting system (CAD/CAM system) using computer-aided design (CAD) technology and a computer-aided manufacturing (CAM) system, and usually includes a turning part in the shape of a block, which is formed of a non-metallic material and has a predetermined shape, and a member for mounting it on the cutting machine. Then, using the CAD/CAM system, the part to be machined is machined (CAM) into the prosthesis shape designed by CAD based on the digital information such as the oral cavity shape and the model shape, to obtain a dental prosthesis having the required shape with high precision. [0006] In addition, when GS is used as a dental prosthetic material, it is necessary to use a material that is matched in color close to the color (expressed as an index including a combination of hue and a mixed index of brightness and saturation, or an index taking into account the tone, brightness and saturation. Hereinafter, the color determined by such an index will also be referred to as the "shade") of natural teeth using a coloring substance such as a pigment, from the point of view of aesthetic properties. Since the color (shade) of natural teeth varies among individuals, GS and CS products are usually manufactured in a tone matched to a variety of different specified colors (shades), and those that match the color of the tooth being restored or the color (shade) of the surrounding teeth are selected and used. [0007] This color (shade) selection (commonly referred to as "shade matching") is typically performed using tooth color samples, called a color guide or shade chart. Various color guides exist, each with a different number of color samples and a dif