JP4481030B2 - Method for producing crown restoration and crown restoration kit therefor - Google Patents

Description

  The present invention relates to a method for producing a crown restoration such as a jacket crown, an inlay, and an onlay, and a crown restoration kit for producing a crown restoration.

  A dental composite restorative material composed of a polymerizable monomer, a photopolymerization initiator and a filler (filler) is generally known. Various physical properties are required for the composite material, but in the restoration of a crown portion and the like where high occlusal pressure is applied, not only aesthetic properties such as surface lubricity but also machines such as bending strength and fracture toughness Durability and biocompatibility are also important physical properties such as mechanical strength, wear resistance against toothbrush wear and occlusal wear, and non-abrasive teeth that do not wear counter teeth due to occlusal wear. It is known that the filler plays a very important role for these physical properties.

For example, it consists of 40 to 99% by weight of substantially spherical inorganic particles having an average particle diameter of more than 0.1 μm and 1 μm or less, and 60 to 1% by weight of inorganic fine particles having an average particle diameter of 0.1 μm or less. A photocurable dental composite restorative material (hereinafter referred to as restorative material 1) containing a filler and a polymerizable monomer has been proposed (for example, Patent Document 1). The restorative material 1 is characterized by excellent bending strength, surface lubricity, and anti-abrasion resistance.

In addition, amorphous inorganic particles having an average particle size of 1 to 9 μm and a particle size of 10 μm or more are 3% by weight or less, substantially spherical inorganic particles having an average particle size of more than 0.1 μm and 5 μm or less, average A filler containing inorganic fine particles having a particle diameter of 0.01 to 0.1 μm , wherein the mixing ratio of the particles in the filler is the weight of each particle with respect to the total weight of the substantially spherical inorganic particles and the inorganic fine particles. A photocurable dental restorative material (hereinafter, restorative material 2) using fillers expressed in terms of ratios of 0.2 to 3, 0.5 to 0.99, and 0.01 to 0.5, respectively. It has been proposed (for example, Patent Document 2). The restoration material 2 has a surface smoothness that can be practically used as a restoration material for a molar portion, and has a feature that its bending strength and fracture toughness are high.

Furthermore, as a restorative material that is more excellent in surface smoothness than the restorative material 2, the amorphous inorganic particles (a) having an average particle diameter of more than 0.1 μm and not more than 1 μm , and the average particle diameter of primary particles is 0.8. A spherical or substantially spherical inorganic particle (b) that is greater than 1 μm and less than or equal to 5 μm , and inorganic particles (c) that have an average primary particle size of 0.1 μm or less, and (a), (b ) And (c) where {ma / (mb + mc)} is 0.2 to 3 and {mb / (mb + mc)} is 0.5 when the mass of each inorganic particle is ma, mb, and mc, respectively. -0.8, and {mc / (mb + mc)} is blended at a ratio satisfying the relationship of 0.2 to 0.5, and a photocurable dental restorative material (hereinafter, restorative material 3) is also included. It has been proposed (for example, Patent Document 3).

JP 2000-26226 A JP 2000-53519 A International Publication No. 02/05752 Pamphlet

Each of the restoration materials 1 to 3 has excellent physical properties, but still has the following points to be improved for use alone in restoration of a crown. That is, the restorative material 1 is excellent in both aesthetics and bending strength. For example, it can be said that the restorative material 1 has sufficient physical properties for restoration of the front tooth portion. However, the conventional restoration material 1 has a fracture toughness value (KIC) of about 2 MPa · m ^1/2 , and was obtained by using the restoration material when used for restoration of a molar portion or the like where high occlusal pressure is applied. The possibility of a broken crown restoration has not been completely wiped out.

  The restorative materials 2 and 3 are both excellent in bending strength and fracture toughness, and in particular, the restorative material 3 has very good aesthetics (surface smoothness). rare. However, since these restorative materials contain irregular shaped inorganic particles, the crown restoration using the restorative material will wear the counter teeth for a long time, that is, the anti-abrasion property of the counter teeth is still improved. There was room.

  Accordingly, there has been a demand for a restoration of a crown that is excellent in both bending strength and fracture toughness, and is excellent not only in surface lubricity but also in anti-abrasion resistance.

The present inventors have intensively studied to solve the above problems. As a result, as the internal structure corresponding to the main body of the crown restoration, a composition having a surface smoothness of a certain level or more and particularly excellent mechanical strength is used. For the part to be used, as the upper forming layer, a composition excellent in surface smoothness and abrasion resistance is used, and further by making each specific filler composition, it is essential when used as a crown restoration material. As a result, the present inventors have found that no difference in appearance between the upper forming layer and the internal structure is confirmed without any reduction in the mechanical strength.

That is, the present invention builds a photocurable composition of the following (I) on an abutment model to obtain an internal structure, and then forms a photocurable composition of the following (II) on the internal structure, The portion that contacts the counter teeth is covered, and the portion corresponding to the tooth neck is exposed to the internal structure, and is partially built up and hardened to have the shape of a crown and has a tooth shape. A method for producing a restoration of a crown, characterized by obtaining a cured product.
(I): It contains a polymerizable monomer, a photopolymerization initiator, and an inorganic filler, and the inorganic filler is a substantially spherical inorganic material having an average primary particle diameter in the range of 0.2 to 0.7 μm. 1% by weight of particles, inorganic fine particles having an average primary particle size of 0.05 to 0.08 μm, and particles having an average primary particle size of 0.9 to 1.2 μm and a particle size of 10 μm or more A photocurable composition (II) that can be obtained by mixing the following amorphous inorganic particles in a proportion of 20 to 50% by mass with respect to the whole inorganic filler. The photocurable composition (I) comprising a monomer, a photopolymerization initiator, and an inorganic filler, wherein the average particle diameter of primary particles is in the range of 0.2 to 0.7 μm. substantially spherical inorganic particles of the same type of substantially spherical inorganic particles are blended,及Which can be an average particle diameter of primary particles is in the range of 0.05～0.08Myuemu, obtained by mixing inorganic fine particles of the same kind of inorganic fine particles are blended in the photo-curable composition (I) And a photocurable composition that does not contain amorphous inorganic particles having a particle size of 0.2 μm or more.

  Another invention is a crown restoration kit for use in the manufacturing method.

  Since the crown restoration obtained by the production method of the present invention is excellent in both bending strength and fracture toughness, it is less likely to break even when used in a molar part. Excellent non-friability. Furthermore, even if the internal structure is exposed on the oral cavity side, the difference in surface lubricity cannot be confirmed with the naked eye, so that repair with excellent aesthetics is possible.

In the present invention, the restoration of the crown is constructed by building up a photocurable composition (I) described later on the abutment model to obtain an internal structure, and then on the internal structure, the photocurable composition ( the II), portion in contact with opposite teeth are coated, in a manner the portion corresponding to the tooth neck of the internal structure is exposed, partially built up city so that the shape of the crown, and further light irradiation By doing so, a hardened body having a crown shape can be obtained.

  The method for manufacturing the abutment model may be a publicly known method of collecting an impression of a site to be repaired in the oral cavity and producing it based on the impression, but is generally as follows. In other words, an impression material such as a dental silicone impression material is collected from a site to be repaired in the oral cavity where the abutment has been constructed and formed, and an abutment model is produced based on the impression. This abutment model can be produced using a plaster model material generally used in the production of dental prostheses.

  In the present invention, a photocurable composition (I), which will be described later, is built on the abutment model obtained by the method as described above so as to cover the abutment model to obtain an internal structure. At this time, it is necessary to build up the portion in contact with the mating tooth to be smaller than the size of the crown restoration to be finally obtained. On the other hand, it is not necessary to make it smaller in the vicinity of the portion that becomes the root of the tooth.

  Before building the photocurable composition (I) on the abutment model, the undercut on the inner surface of the model may be blocked out using wax or the like, if necessary. Also, if necessary, use a separating material or mold release material to prevent adhesion between the plaster model and the photocurable composition, or use a spacer to secure dental cement space. Also good.

  After building up the photocurable composition (I) in a desired shape, the photocurable composition (II) described later is built up on the photocurable composition (II). In advance, the photocurable composition (I) may be cured by light irradiation. Furthermore, from the viewpoint of work efficiency, when building up the photocurable composition (I), the photocurable composition (I) is divided into several stages such as partially building up, light irradiation, and building up again. You may go.

On the internal structure made of the photocurable composition (I) and / or the cured product of the photocurable composition (I) produced as described above, the photocurable composition (II) is paired. The portion in contact with the denture is covered, and the portion corresponding to the tooth neck is constructed so as to have the shape of a crown in such a manner that the internal structure is exposed . Even when the photocurable composition (II) is built up, partial building up and light irradiation may be repeated.

  Thus, after obtaining the photocuring body which has a tooth | gear shape, heating at 90-140 degreeC further as needed is suitable when raising mechanical strength further.

  What is necessary is just to use the crown restoration obtained in this way according to a well-known method. That is, the crown restoration obtained by photocuring (and thermosetting) is further subjected to shape correction, polishing and polishing, and mounted in the oral cavity using dental cement or the like.

  The thickness of the restoration of the crown produced by the method of the present invention largely depends on the case, and generally, the restoration is not a restoration having a uniform thickness. Typically, the thickness of the photocurable composition (I) is preferably 0.5 mm or more, and more preferably 1.0 mm or more. Moreover, as thickness of photocurable composition (II), it is preferable that it is 0.2 mm or more, and it is more preferable that it is 0.5 mm or more. Moreover, as ratio of both thickness, it is suitable that the ratio of the curable composition for light (I) is 40 to 90% of the whole on average.

The crown restoration obtained by the production method of the present invention has a structure in which the cured product of the photocurable composition (I) is substantially covered with the cured product of the photocurable composition (II), that is, the interior ( The abutment side) is formed of a cured body (internal structure) of the photocurable composition (I), and the exterior (oral cavity side) is formed of a cured body of the photocurable composition (II). However, the cured product of the photocurable composition (I) is not completely covered with the cured product of the photocurable composition (II), and the portion corresponding to the tooth neck is the photocurable composition. A restoration of the crown from which the cured product (I) is exposed. That is, the portion corresponding to the tooth neck is often thin as a crown restoration. Therefore, in order to prevent breakage of the portion corresponding to the cervical region, the layer of the cured body of the photocurable composition (I) is made thinner in order to cover with the cured body of the photocurable composition (II). also, it is better to form all of the cured product of the photocurable composition (I). Since the vicinity of the tooth neck does not contact the counter teeth, the effect of the present invention is not lost.

Since the present invention produces a crown restoration in which the internal structure is partially exposed in this way, the effect is exhibited. That is, since the cured product of the photocurable composition ( I ) is excellent in surface smoothness, the gloss between the internal structure composed of the cured product and the outer layer portion composed of the cured product of the photocurable composition ( II ). There is almost no difference between them, and it can be used without any problem in appearance. On the other hand, when a composition such as the above-described conventionally known restoration material 2 is used as the material of the internal structure, there is often a difference in gloss with the outer layer portion.

  In the method for producing a restoration of a dental crown of the present invention, two kinds of photocurable compositions are used.

The photocurable composition (I) comprises a polymerizable monomer, a photopolymerization initiator, and an inorganic filler, and the inorganic filler has a primary particle average particle size in the range of 0.2 to 0.7 μm. The substantially spherical inorganic particles, the fine particles having an average primary particle diameter of 0.05 to 0.08 μm, and the primary particles have an average particle diameter of 0.9 to 1.2 μm and a particle diameter of 10 μm or more. This is a photocurable composition obtained by mixing amorphous inorganic particles having a particle size of 1% by weight or less with a proportion of 20 to 50% by mass of the amorphous inorganic particles with respect to the entire inorganic filler .

  As the polymerizable monomer, known dental polymerizable monomers can be used without limitation. Examples of the polymerizable monomer that can be suitably used include monomers having an acryloyl group and / or a methacryloyl group. Specific examples of such polymerizable monomers include the following [I-1] to [I- 4].

  [I-1] Monofunctional vinyl monomer: Methacrylate such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, hydroxyethyl methacrylate, tetrahydrofurfuryl methacrylate, glycidyl methacrylate, and acrylates corresponding to these methacrylates; or acrylic acid, methacrylic acid, p-methacryloyloxybenzoic acid, N-2-hydroxy-3-methacryloyloxypropyl-N-phenylglycine, 4-methacryloyloxyethyl trimellitic acid and its anhydride, 6-methacryloyloxyhexamethylenemalonic acid, 10-methacryloyl Oxydecamethylenemalonic acid, 2-methacryloyloxyethyl dihydrogen phosphate, 10-methacryloyloxydeca Chi-range hydrogen phosphate, 2-hydroxyethyl hydrogen phenyl phosphonate or the like.

[I-2] Bifunctional vinyl monomer (i) Aromatic compound-based 2,2-bis (methacryloyloxyphenyl) propane, 2,2-bis [4- (3-methacryloyloxy) -2-hydroxypropoxy Phenyl] propane (hereinafter abbreviated as bis-GMA), 2,2-bis (4-methacryloyloxyphenyl) propane, 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane (hereinafter referred to as bis-MEPP) Abbreviation), 2,2-bis (4-methacryloyloxydiethoxyphenyl) propane), 2,2-bis (4-methacryloyloxytetraethoxyphenyl) propane, 2,2-bis (4-methacryloyloxypentaethoxyphenyl) ) Propane, 2,2-bis (4-methacryloyloxydipropoxyphe) ) Propane, 2 (4-methacryloyloxydiethoxyphenyl) -2 (4-methacryloyloxydiethoxyphenyl) propane, 2 (4-methacryloyloxydiethoxyphenyl) -2 (4-methacryloyloxyditriethoxyphenyl) propane, 2 (4-methacryloyloxydipropoxyphenyl) -2- (4-methacryloyloxytriethoxyphenyl) propane, 2,2-bis (4-methacryloyloxypropoxyphenyl) propane, 2,2-bis (4-methacryloyloxyiso) Propoxyphenyl) propane, and acrylates corresponding to these methacrylates; 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, etc. Diadducts obtained from addition of methacrylate monomers or vinyl monomers having —OH groups such as acrylates corresponding to these methacrylates and diisocyanate compounds having aromatic groups such as diisocyanate methylbenzene and 4,4′-diphenylmethane diisocyanate etc.

  (Ii) Aliphatic compounds of ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate (hereinafter abbreviated as TEGDMA), butylene glycol dimethacrylate, neopentyl glycol dimethacrylate, propylene glycol dimethacrylate, 1, 3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate (hereinafter abbreviated as HDDM), and acrylates corresponding to these methacrylates; 2-hydroxyethyl methacrylate, 2- Methacrylates such as hydroxypropyl methacrylate and 3-chloro-2-hydroxypropyl methacrylate, or polymers corresponding to these methacrylates A diadduct obtained from the addition of a vinyl monomer having an —OH group such as acrylate and a diisocyanate compound such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diisocyanate methylcyclohexane, isophorone diisocyanate, methylenebis (4-cyclohexylisocyanate), For example, 1,6-bis (methacrylethyloxycarbonylamino) -2,2-4-trimethylhexane (hereinafter abbreviated as UDMA); acrylic acid anhydride, methacrylic acid anhydride, 1,2-bis (3-methacryloyloxy- 2-hydroxypropoxy) ethyl, di (2-methacryloyloxypropyl) phosphate and the like.

  [I-3] Trifunctional vinyl monomers such as trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, pentaerythritol trimethacrylate, trimethylolmethane trimethacrylate (hereinafter abbreviated as TMPT), and methacrylates thereof. Corresponding acrylate etc.

  [I-4] Tetrafunctional vinyl monomers pentaerythritol tetramethacrylate, pentaerythritol tetraacrylate and diisocyanate methylbenzene, diisocyanate methylcyclohexane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, methylenebis (4-cyclohexyl isocyanate), 4 Diadducts obtained from the addition of diisocyanate compounds such as 1,4-diphenylmethane diisocyanate and tolylene-2,4-diisocyanate and glycidol dimethacrylate.

  Among the above exemplified examples, particularly preferred polymerizable monomers include bis-GMA, bis-MEPP, TEGDMA, UDMA, TMPT, HDDM and the like.

  The above polymerizable monomers may be used alone or in combination of two or more. In particular, it is preferable to use a mixture of three or more kinds in order to adjust the mechanical strength, refractive index, and viscosity.

  As the photopolymerization initiator used in the photocurable composition (I), known ones can be used without limitation, and specifically, benzoin alkyl ethers such as benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether, Benzyl ketals such as benzyl dimethyl ketal and benzyl diethyl ketal, benzophenones such as benzophenone, 4,4′-dimethylbenzophenone and 4-methacryloxybenzophenone, diacetyl, 2,3-pentadione benzyl, camphorquinone, 9,10- Α-diketones such as phenanthraquinone and 9,10-anthraquinone, thioxanthone compounds such as 2,4-diethoxythioxanthone, 2-chlorothioxanthone and methylthioxanthone, 2,4,6-trimethylbenzoyl Diphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -4 Bisacylphosphine oxides such as -propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide can be used.

  In addition, a reducing agent is often added to the photopolymerization initiator as a polymerization initiation assistant. Examples thereof include 2- (dimethylamino) ethyl methacrylate, ethyl 4-dimethylaminobenzoate, and N-methyldiethanolamine. And tertiary amines, aldehydes such as lauryl aldehyde, dimethylaminobenzaldehyde, terephthalaldehyde, and sulfur-containing compounds such as 2-mercaptobenzoxazole, 1-decanthiol, thiosalicylic acid, and thiobenzoic acid.

  Particularly suitable photopolymerization initiators include camphorquinone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide. In particular, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide have a long operation margin and are unpolymerized when used as a dental restoration composition. It is preferable because of its small amount and little discoloration.

  The photopolymerization initiator / reducing agent may be used alone or in combination of two or more.

  The blending amount of the photopolymerization initiator may be arbitrarily determined in consideration of physical properties and the like. However, if a suitable range is exemplified, 0.01 to 5 weights with respect to 100 weight parts of the polymerizable monomer. Parts, more preferably 0.1 to 5 parts by weight.

The inorganic filler compounded in the photocurable composition (I) is a substantially spherical inorganic particle having an average primary particle size in the range of 0.2 to 0.7 μm, and an average primary particle size of 0.00. By mixing inorganic fine particles in the range of 05 to 0.08 μm and amorphous inorganic particles having an average primary particle size of 0.9 to 1.2 μm and a particle size of 10 μm or more of 1% by weight or less Any method can be used as long as it can be obtained, and the method for obtaining the inorganic filler is not particularly limited. In general, the inorganic filler may be mixed and produced.

The substantially spherical inorganic particles are not particularly limited as long as the average particle diameter is in the range of 0.2 to 0.7 μm and the shape is substantially spherical . The particle size distribution of the inorganic particles should be excellent in monodispersity such that the coefficient of variation in particle diameter is within 0.3, so that the abundance ratio of large particles is reduced, surface lubricity, It is more preferable from the viewpoint of improving the wearability and the non-abrasion property of the mating teeth, and from the viewpoint of close packing. Here, the substantially spherical shape means a direction in which particles observed in the unit field of view are rounded and orthogonal to the maximum diameter of the filler taken with a scanning electron microscope (hereinafter abbreviated as SEM). The average uniformity obtained by dividing the particle diameter by the maximum diameter is 0.6 or more. When the shape of the inorganic particles is not substantially spherical, there is a risk that the filling rate will decrease as the specific surface area increases, and the surface smoothness and the non-abrasive nature of the teeth will deteriorate.

  The production method of these substantially spherical inorganic particles is not particularly limited, but can be suitably produced by the methods described in, for example, JP-A Nos. 58-110414 and 58-156524.

  The material of the substantially spherical inorganic particles is not particularly limited, and known materials can be used, and inorganic oxides such as amorphous silica, silica-zirconia, silica-titania, silica-titania-barium oxide, quartz, alumina, etc. It is common that. As these inorganic oxides, a small amount of a Group I metal oxide was present in the inorganic oxide for the purpose of easily obtaining a dense inorganic oxide upon firing at a high temperature. Complex oxides can also be used. As the material of the substantially spherical inorganic particles, a complex oxide mainly composed of silica and zirconia is particularly preferable because a cured body having X-ray contrast properties and more excellent wear resistance can be obtained. Used.

  The substantially spherical inorganic particles do not necessarily have to be a single filler as long as the average particle size is within the above range. For example, as shown in Japanese Patent Publication No. 3-10603, the average particle size and material (component) May be a mixture of different fillers.

  The substantially spherical inorganic particles are preferably used after the surface is treated with an appropriate surface treating agent for the purpose of improving the dispersibility in the polymerizable monomer as a matrix. The method for the treatment is not particularly limited, and a known method is employed without limitation. For example, a typical surface treatment method is a treatment with a silane coupling agent such as γ-methacryloyloxyalkyltrimethoxysilane or hexamethyldisilazane or a titanate coupling agent as the surface treatment agent. There is a method of graft-polymerizing the polymerizable monomer on the particle surface.

In particular, the general formula
CH ₂ = C (R ¹ ) -COO- (CH ₂ ) _n -Si- (R ² ) _m (R ³ ) _3-m
{Wherein R ¹ is a hydrogen atom or a methyl group, R ² is an alkoxy group, a chlorine atom, or an isocyanate group, R ³ is an alkyl group having 1 to 6 carbon atoms, and m is 2 to 3 N is an integer of 8-20. }
When the surface treatment is performed using a silane coupling agent in which a (meth) acrylate group is bonded to a silicon atom via a long chain alkylene group, the affinity with the polymerizable monomer may be improved. This is preferable because it is possible. When the inorganic filler filling rate is improved, it is expected that the thermal expansion is reduced or the wear resistance is improved, thereby improving the durability of the restoration in the oral cavity. Examples of the silane coupling agent represented by the above general formula include 10-methacryloyloxydecyltrimethoxysilane, 11-methacryloyloxyundecylmethyldimethoxysilane, 11-methacryloyloxyundecyltrichlorosilane, and the like.

  These silane coupling agents may be used alone or in combination of two or more. Moreover, as long as the effect is not impaired, it can also be used in combination with known surface treatment agents other than the silane coupling agent represented by the above general formula. A method for surface-treating the inorganic filler using a silane coupling agent is not particularly limited, and a known method can be used. Specifically, a method in which the inorganic filler and the silane coupling agent are dispersed and mixed in a suitable solvent using a ball mill or the like, dried with an evaporator or a spray dryer, and then heated to 50 to 150 ° C. The inorganic filler and the silane coupling agent may be heated in a solvent such as alcohol with stirring.

  At this time, the amount of the silane coupling agent to be used is not particularly limited, and an optimal value may be determined after confirming in advance experiments the mechanical properties of the obtained cured product. For example, the surface treatment agent is in the range of 1 to 10 parts by weight with respect to 100 parts by weight of the inorganic particles.

The inorganic fine particles are not particularly limited as long as the average particle diameter is in the range of 0.05 to 0.08 μm, and the shape may be spherical or irregular . The particle size distribution of the inorganic particles should be excellent in monodispersity such that the coefficient of variation in particle diameter is within 0.3, so that the abundance ratio of large particles is reduced, surface lubricity, This is preferable from the viewpoint of improving the wear resistance and non-abrasion of the teeth.

  The production method and material of these inorganic fine particles are not particularly limited, and known ones can be used, and the production method and material similar to those of the substantially spherical inorganic particles may be used. Further, like the substantially spherical inorganic particles, it is preferable to use the surface after treating the surface with an appropriate surface treating agent for the purpose of improving the dispersibility in the polymerizable monomer as a matrix.

The amorphous inorganic particles are not particularly limited as long as the particles having an average particle size of 0.9 to 1.2 μm and a particle size of 10 μm or more are 1% by weight or less. Further, it is more preferable that the primary particles having a particle diameter of 5 μm or more are 1% or less. Here, the irregular shape in the present invention means that the shape of the primary particles observed by SEM or the like has a large number of irregular corners and surfaces, and particles usually obtained by crushing or grinding. Point to.

  By blending such irregularly shaped particles, for example, in a composition comprising a filler composition consisting only of spherical particles, when a fracture starting point such as a crack is formed in the material, the crack extends in one direction. It is thought that the property which becomes easy to do has the effect of being suppressed.

  The material of the amorphous inorganic particles is not particularly limited, and known materials can be used. Specifically, borosilicate glass, soda glass, glass containing heavy metals (for example, barium, strontium, zirconium), aluminosilicate, fluoroaluminosilicate, glass ceramics, silica, silica / zirconia, silica / titania, silica / alumina, etc. A composite inorganic oxide or the like is preferable. A particularly preferred example is a composite oxide mainly composed of silica and zirconia since a cured product having X-ray contrast properties and more excellent wear resistance can be obtained.

  The amorphous inorganic particles are preferably used after the surface is treated with an appropriate surface treating agent for the purpose of improving the dispersibility in the polymerizable monomer as a matrix. As the method for the treatment, the surface treatment method for substantially spherical inorganic particles can be used without any limitation as described above.

In the photocurable composition (I), the amount of filler added to the substantially spherical inorganic particles (A1), the inorganic fine particles (B1), and the amorphous inorganic particles (C) is 100 parts by weight of the polymerizable monomer. On the other hand, a range of 200 to 1900 parts by weight, more preferably 300 to 900 parts by weight is preferable from the viewpoint of mechanical strength and operability. The blending ratio [(C) / ((A1) + (B1) + (C))] of the amorphous inorganic particles (C) is 0.2 to 0.5, preferably 0.2. It is the range which becomes -0.4. That is, the compounding ratio with respect to the whole inorganic filler of an amorphous inorganic particle (C) is 20-50 mass%. Furthermore, when the suitable range of the compounding ratio of the substantially spherical inorganic particles (A1) and the inorganic fine particles (B1) is exemplified, (A1) / ((A1) + (B1) + (C)) is 0 by mass ratio. 0.1 to 0.9, more preferably 0.3 to 0.6, and (B1) / ((A1) + (B1) + (C)) is 0.2 to 0.4, more preferably 0.3. It is the range which becomes -0.6.

The photocurable composition (II) used in the production method of the present invention comprises a polymerizable monomer, a photopolymerization initiator, and an inorganic filler, and the inorganic filler has an average primary particle size of 0.00. The average particle diameter of the substantially spherical inorganic particles of the same kind as the substantially spherical inorganic particles blended with the photocurable composition (I) in the range of 2 to 0.7 μm and the primary particles is 0.05. It can be obtained by mixing the same kind of inorganic fine particles as those mixed with the photocurable composition (I) in the range of ~ 0.08 μm, and has a particle diameter of 0.2 μm or more. It is a photocurable composition which does not contain the amorphous inorganic particles.

  The polymerizable monomer and photopolymerization initiator used in the photocurable composition (II) are the same as those described for the photocurable composition (I).

The inorganic filler compounded in the photocurable composition (II) is an abbreviated compounding of the photocurable composition (I) in which the average particle diameter of primary particles is in the range of 0.2 to 0.7 μm . Spherical inorganic particles of the same kind as the spherical inorganic particles, and inorganic fine particles blended with the photocurable composition (I) having an average primary particle size in the range of 0.05 to 0.08 μm. the same kind of are those that can be obtained by mixing the inorganic fine particles should and can contain more irregular inorganic particles having a particle diameter 0.2 [mu] m. The method for obtaining the inorganic filler is not particularly limited, but in general, the photocurable composition (I) in which the average particle diameter of the primary particles is in the range of 0.2 to 0.7 μm. Includes substantially spherical inorganic particles of the same type as the blended substantially spherical inorganic particles, and particles having an average primary particle size in the range of 0.05 to 0.08 μm and a particle size of 0.2 μm or more. What is necessary is just to mix and manufacture the inorganic fine particle mix | blended with the photocurable composition (I) and the same kind of inorganic particle.

The substantially spherical inorganic particles having an average primary particle diameter in the range of 0.2 to 0.7 μm are the same as those described as the components of the inorganic filler blended in the photocurable composition (I). but it can be used in the context of the same kind of material as substantially spherical inorganic particles are blended with the photocurable composition (I).

Inorganic fine particles having an average primary particle size in the range of 0.05 to 0.08 μm are also blended with the photocurable composition (I) except for those containing particles having a particle size of 0.2 μm or more. the same ones as described as a component of the inorganic filler can be used in the context of the inorganic fine particles of the same type of material that is blended with the photocurable composition (I).

  In the photocurable composition (II), the blending amount of the filler obtained by adding the substantially spherical inorganic particles (A2) and the inorganic fine particles (B2) is 200 to 1900 parts by weight with respect to 100 parts by weight of the polymerizable monomer. More preferably, it is in the range of 300 to 900 parts by weight from the viewpoint of mechanical strength and operability. When a suitable range of the mixing ratio of the substantially spherical inorganic particles (A2) and the inorganic fine particles (B2) is exemplified, (A2) / ((A2) + (B2)) is 0.1 to 0.9 by mass ratio. More preferably, it is the range which becomes 0.4-0.7.

  In the said photocurable composition (I) and (II), a well-known additive can be mix | blended in the range which does not inhibit the effect remarkably. Examples of such additives include polymerization inhibitors, fluorescent agents, ultraviolet absorbers, pigments and the like. Specific examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, dibutylhydroxytoluene, phenothiazine and the like. Specific examples of the fluorescent agent include 2,2 ′-(thiophendiyl) -bis (tert-butyl-benzoxazole), 7- (4′-chloro-6 ″ -diethylamino-1 ′, 3 ′, 5 ′ -Triazin-4'-yl) -amino-3-phenyl-coumarin, diethyl dihydroxyterephthalate and the like. Specific examples of the ultraviolet absorber include 2- (5-methyl-2-hydroxyphenyl) benzotriazole, vitamin C, 2-hydroxy-4-methoxybenzophenone, titanium oxide, zinc oxide and the like.

  Each of the above-mentioned photocurable compositions is generally used after taking a predetermined amount of each of the essential components and, if necessary, each optional component, mixing them, and vacuum degassing. The inorganic filler may be added to the polymerizable monomer after mixing various inorganic particles, or may be added separately to the polymerizable monomer. The photocurable composition thus obtained may be stored in a light-shielding container, stored and distributed, and examples of the container include a syringe, a compute, a lidded lid and the like. It is done.

  In the production method of the present invention, since the photocurable composition (I) and the photocurable composition (II) are always used in combination, the photocurable composition (I) and the photocurable composition are used. It is preferable to provide a crown restoration kit in combination with the product (II). As the crown restoration kit, other members such as opaque, stain, separator, abrasive and the like, which are necessary for manufacturing the restoration of the crown, may be provided together.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not restrict | limited to these Examples.

In addition, the polymerizable monomer, photoinitiator, and filler which were used by the Example and the comparative example are as follows.
(1) Polymerizable monomer composition M-1: D-2.6E (70) / TEGDMA (15) / UDMA
(15)
M-2: D-2.6E (80) / TEGDMA (10) / UDMA
(10)
(2) Photopolymerization initiator C-1: bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide C-2: 2,4,6-trimethylbenzoyldiphenylphosphine oxide, (50) / dimethylaminobenzoic acid Ethyl ester (50)
(3) Filler FA-1: Spherical silica-zirconia, average particle size; 0.4 μm
FB-1: fine particle silica-titania, average particle diameter; 0.07 μm
FC-1: Amorphous silica-zirconia, average particle size: 1.2 μm , 0% by weight of particles having a particle size of 10 μm or more, γ-methacryloyloxypropyltrimethoxysilane surface-treated product FC-2: Amorphous silica Zirconia, average particle size: 0.9 μm , 0% by weight of particles having a particle size of 10 μm or more, 10-methacryloyloxyundecyltrimethoxysilane surface-treated product FC-3: amorphous silica-zirconia, average particle size: 1 .2 μm , 0% by weight of particles having a particle diameter of 10 μm or more, γ-methacryloyloxypropyltrimethoxysilane (20) / 11-methacryloyloxyundecylmethyldimethoxysilane (80) surface-treated product FC-4: amorphous silica -Zirconia, average particle size: 3.2 μm , particles having a particle size of 10 μm or more are 3.0% by weight, γ-methacryloyl Oxypropyltrimethoxysilane surface-treated product FC-5: Amorphous silica-zirconia, average particle size: 0.3 μm , 0% by weight of particles having a particle size of 10 μm or more, 10-methacryloyloxyundecyltrimethoxysilane surface treatment In the examples and comparative examples, each measured value was measured by the following method.

(1) Opposite tooth wear depth A cylindrical mold with a diameter of 6 mm and a height of 6 mm is first filled with a photocurable composition (II), and light-cured with a technical light irradiator α light (Morita). Next, the bottom surface of the columnar sample piece obtained by filling and photocuring the photocurable composition (I) in the same manner is rotated while being pressed against a bovine enamel plane with a load of 100 g under 37 ° C. water injection. Abrasion of 10,000 revolutions was performed. A step on the flat surface of the bovine enamel was measured with a surface roughness meter to determine the anti-tooth wear depth [μm].

(2) Difference in glossiness Half of a 10 mm × 10 mm × 2 mm mold is filled with the photocurable composition (I), and the other half is filled with the photocurable composition (II). A cured product was produced by irradiation with α light (Morita) for 5 minutes each in the vertical direction. This was polished with # 1500 water-resistant polishing paper, and then polished with a Robinson brush using a diamond paste type abrasive, was used as a sample piece. The polished surface was visually observed under a fluorescent lamp, and the case where the difference in glossiness could not be confirmed was evaluated as ◯, and the case where the difference in glossiness could be confirmed as x.

(3) Fracture toughness value: First, a photocurable composition (I) was filled in a prismatic mold having a width of 2 mm, a height of 4 mm, and a length of 20 mm so as to be approximately 70%, and then the upper portion was photocured. Filled with composition (II). Using a light irradiator α light (manufactured by Morita) for technical use, each of the upper and lower parts was irradiated with 5 spectra, and further heated and polymerized at 120 ° C. for 20 minutes in a heating polymerizer to prepare a sample piece. A 2 mm crack was made in the height direction with a diamond cutter to prepare a sample piece with a notch on one side. This sample piece is mounted on a testing machine (manufactured by Shimadzu Corp., Autograph 500D), and a three-point bending test is performed at a fulcrum distance of 16 mm and a crosshead speed of 1.0 mm / min. The fracture toughness value [MPa · m ^1/2 ] was calculated.

Example 1
40 g of FA-1 and 30 g of FB-1 were mixed and dispersed, and 7 g of mixed particles obtained by subjecting the surface treatment agent γ-methacryloyloxypropyltrimethoxysilane to surface treatment and 3 g of FC-1 were put in a mortar. Matrix monomer M-1 in which C-1 was dissolved by 1% by weight as a photopolymerization initiator was gradually added and mixed to the limit indicating the paste state to obtain a curable composition. This curable composition was designated as a photocurable composition (I).

  Also, 60 g of FA-1 and 40 g of FB-1 were mixed and dispersed, and 10 g of inorganic filler consisting of mixed particles obtained by surface treatment with a surface treatment agent γ-methacryloyloxypropyltrimethoxysilane was taken in a mortar. A curable composition was obtained by gradually adding and mixing a matrix monomer M-1 in which C-1 was dissolved in a weight ratio of 1% in advance as a photopolymerization initiator to the limit indicating the paste state. This curable composition was designated as a photocurable composition (II).

  Various physical properties were measured by the measurement methods described above using the above curable compositions. The composition is shown in Table 1, and the results are shown in Table 2.

Example 2
A curable composition was obtained in the same manner as in Example 1 except that FC-2 was used instead of FC-1, and various characteristics were evaluated. The composition is shown in Table 1, and the results are shown in Table 2.

Example 3
A curable composition was obtained in the same manner as in Example 1 except that FC-3 was used instead of FC-1, and various characteristics were evaluated. The composition is shown in Table 1, and the results are shown in Table 2.

Example 4
A curable composition was obtained in the same manner as in Example 1 except that C-2 was used instead of C-1, and various characteristics were evaluated. The composition is shown in Table 1, and the results are shown in Table 2.

Example 5
A curable composition was obtained in the same manner as in Example 4 except that M-2 was used instead of M-1, and various characteristics were evaluated. The composition is shown in Table 1, and the results are shown in Table 2.

Examples 6-8
A curable composition was prepared in the same manner as in Example 1 except that the proportion of the inorganic filler to be blended was changed as shown in Table 1. Using these curable compositions, various physical properties were measured by the measurement methods described above. The composition is shown in Table 1, and the results are shown in Table 2.

  Comparative Example 1 Using only the photocurable composition (II) of Example 1, various physical properties were measured by the measurement method described above. The composition is shown in Table 1, and the results are shown in Table 2.

  Comparative Example 2 Using only the photocurable composition (I) of Example 1, various physical properties were measured by the measurement method described above. The composition is shown in Table 1, and the results are shown in Table 2.

  Comparative Example 3 A curable composition was obtained in the same manner as in Example 1 except that FC-4 was used instead of FC-1, and various characteristics were evaluated. The composition is shown in Table 1, and the results are shown in Table 2. A clear difference in glossiness appeared.

  Comparative Example 4 A curable composition was obtained in the same manner as in Example 1 except that FC-5 was used instead of FC-1, and various characteristics were evaluated. The composition is shown in Table 1, and the results are shown in Table 2.

The cross-sectional schematic diagram of the crown restoration obtained by the manufacturing method of this invention.

Explanation of symbols

1: Abutment model 2: Internal structure constructed by photocurable composition (I) 3: Outer layer part (dental crown) constructed by photocurable composition (II)
4: Tooth neck portion of internal structure

Claims (2)

The following (I) photocurable composition is built on the abutment model to obtain an internal structure, and then the following (II) photocurable composition is brought into contact with the counter tooth on the internal structure. The portion is covered, and the portion corresponding to the tooth neck is exposed in the form of the internal structure, and is partially built up and hardened so as to have a crown shape, thereby obtaining a hardened body having a tooth shape. Characteristic method for producing crown restorations:
(I): It contains a polymerizable monomer, a photopolymerization initiator, and an inorganic filler, and the inorganic filler is a substantially spherical inorganic material having an average primary particle diameter in the range of 0.2 to 0.7 μm. 1% by weight of particles, inorganic fine particles having an average primary particle size of 0.05 to 0.08 μm, and particles having an average primary particle size of 0.9 to 1.2 μm and a particle size of 10 μm or more the following amorphous inorganic particles, the amorphous inorganic particles relative to the entire inorganic filler photocurable composition are those which can be obtained by mixing at a ratio of 20 to 50 wt% (II): polymerizable monomer The photocurable composition (I) comprising a monomer, a photopolymerization initiator, and an inorganic filler, wherein the average particle diameter of primary particles is in the range of 0.2 to 0.7 μm. substantially spherical inorganic particles of the same type of substantially spherical inorganic particles are blended,及Which can be an average particle diameter of primary particles is in the range of 0.05～0.08Myuemu, obtained by mixing inorganic fine particles of the same kind of inorganic fine particles are blended in the photo-curable composition (I) And a photocurable composition that does not contain amorphous inorganic particles having a particle size of 0.2 μm or more. (I) A substantially spherical inorganic particle comprising a polymerizable monomer, a photopolymerization initiator, and an inorganic filler, wherein the inorganic filler has an average particle diameter of primary particles in the range of 0.2 to 0.7 μm. 1% by weight or less of inorganic fine particles having an average primary particle size in the range of 0.05 to 0.08 μm, and particles having an average primary particle size of 0.9 to 1.2 μm and a particle size of 10 μm or more. A photocurable composition that can be obtained by mixing the amorphous inorganic particles in a proportion of 20 to 50% by mass with respect to the whole inorganic filler ,
(II) The photocurable resin comprising a polymerizable monomer, a photopolymerization initiator, and an inorganic filler, wherein the inorganic filler has an average primary particle diameter in the range of 0.2 to 0.7 μm . The photocurable composition , wherein the substantially spherical inorganic particles of the same kind as the substantially spherical inorganic particles blended in the composition (I) and the average particle diameter of the primary particles are in the range of 0.05 to 0.08 μm. A photocurable composition that can be obtained by mixing the same kind of inorganic fine particles as those blended with the product (I) and does not contain amorphous inorganic particles having a particle diameter of 0.2 μm or more; ,
The crown restoration kit for using for the manufacturing method of Claim 1 comprised from these.

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