WO2015141683A1

WO2015141683A1 - Orthodontic adhesive and orthodontic adhesive kit

Info

Publication number: WO2015141683A1
Application number: PCT/JP2015/057913
Authority: WO
Inventors: 喜孝稲木; 恭子上村; 倩崔; 広一郎平田
Original assignee: 株式会社トクヤマデンタル; 喜孝稲木; 恭子上村; 倩崔; 広一郎平田
Priority date: 2014-03-19
Filing date: 2015-03-17
Publication date: 2015-09-24
Also published as: JPWO2015141683A1; JP6396429B2

Abstract

　The present invention exhibits exceptional removability of excess adhesive and exceptional cuttability of a cured product obtained by curing the adhesive. An orthodontic adhesive containing: 250-750 parts by mass of a filler (A), the filler (A) containing 10-35 mass% of an inorganic filler component (A1) which comprises particles of spherical or substantially spherical shape and has an average primary particle size of 0.07-0.6 μm and 65-90 mass% of a filler component (A2) having an average particle size of 0.7-35 μm; 100 parts by mass of a polymerizable monomer (B); and 0.01-10 parts by mass of a polymerization initiator (C), 60 mass% or more of the filler component (A2) in the orthodontic adhesive being a filler component (A3) comprising particles having a Vickers hardness HV of less than 750, as well as an orthodontic adhesive kit using the orthodontic adhesive.

Description

Orthodontic adhesive and orthodontic adhesive kit

The present invention relates to an orthodontic adhesive and an orthodontic adhesive kit.

In orthodontic treatment using an orthodontic member such as a bracket, an operation of mounting the orthodontic member on the tooth surface is performed. When the orthodontic member is mounted on the tooth surface, the teeth are generally pretreated with a tooth surface pretreatment agent in advance. Then, after applying a chemical or photo-curing orthodontic adhesive to the base of the orthodontic member on the pretreated tooth surface, the base of the orthodontic member is to be corrected. Press contact with the surface. At the time of pressure contact, excessive orthodontic adhesive overflows on the tooth surface of the orthodontic member periphery. Alternatively, an orthodontic member is disposed on the pretreated tooth surface, and an orthodontic adhesive is placed so as to cover the orthodontic member. When placing, usually a lot of orthodontic adhesive is often placed, and in this case, the pile of the placed orthodontic adhesive contains extra orthodontic adhesive. become. As described above, when the tooth surface and the orthodontic member are bonded, an excessive orthodontic adhesive (hereinafter referred to as “an excess orthodontic adhesive”) is attached to the bonding portion between the tooth surface and the orthodontic member. Often referred to as “surplus adhesive”. If this surplus adhesive is cured and remains on the tooth surface, it may cause caries during the treatment period. Further, when the orthodontic member is removed after the treatment, if there are many hardened bodies of the orthodontic adhesive material attached to the tooth surface, an extra burden is placed on the tooth quality.

In order to avoid such a problem, usually, after the orthodontic member and the tooth surface are bonded, they are removed from the tooth surface before the excessive adhesive is cured. The removal of the excess adhesive material before curing is conventionally performed using a dedicated instrument such as a probe. However, when the conventional orthodontic adhesive is removed with a probe or the like, a phenomenon called so-called stringing occurs in which the orthodontic adhesive continuously stretches into a thread shape. This phenomenon makes it difficult to remove the surplus adhesive material, which is a burden on the operator in clinical practice. Since there is little stringing of the orthodontic adhesive, it becomes possible to remove the orthodontic adhesive overflowing to the peripheral edge of the orthodontic member in a lump and to shorten the operation time (hereinafter referred to as the operation time). In some cases, the “removability is good” or “operability is good” of the surplus adhesive may be referred to in terms of the ease of removing the surplus adhesive).

Also, when the dentition is improved after the treatment with the orthodontic member, it is necessary to remove the orthodontic member from the tooth surface. In addition, the orthodontic member may fall off the tooth surface unexpectedly during treatment. In such a case, the cured body of the orthodontic adhesive often remains attached to the tooth surface. Such a hardened body is removed by cutting with a dedicated tool such as a bar or an engine. However, conventional orthodontic adhesives have a high filling rate (filling ratio of the filling material relative to the total mass of the orthodontic adhesive), so that the hardened body is hard and difficult to remove from the tooth surface. It was a burden on the person. Depending on the case, the tooth surface may be damaged or the tooth quality may be damaged (hereinafter, regarding the ease of removal of the remaining hardened body by cutting, if the removal is easy, “cutting is good” If removal is difficult, it may be described as “poor machinability”).

So far, orthodontic adhesives in which fumed silica is blended with fillers have been proposed as means for improving the removal of excess adhesive and the cutting ability of hardened bodies (Patent Document 1). According to this technique, by including a relatively large amount of hydrophobized fumed silica (10 to 50% by mass in the filler), the orthodontic adhesive itself can be continuously stretched into a string. It is described that the phenomenon called is improved and the machinability can be improved.

Also, Patent Document 2 discloses that an adhesive containing fumed silica and quartz filler is used for orthodontic treatment.

On the other hand, in addition to orthodontic treatment, various adhesives used in the oral cavity have been proposed. For example, Patent Document 3 proposes a curable composition composed of an inorganic filler and a polymerizable monomer mainly for the purpose of filling and repairing a cavity formed in a tooth. A feature of the curable composition of Patent Document 3 is that amorphous inorganic particles and spherical inorganic particles are used at a specific ratio in the inorganic filler in order to improve the mechanical strength of the cured product of the curable composition. In this example, a high bending strength of 2000 kg / cm ² or more is achieved. Further, since the curable composition described in Patent Document 3 is used for the purpose of filling and restoration, unlike the orthodontic adhesive, it is extremely low in polymerization shrinkage rate and polymerization shrinkage stress at the time of curing. It is considered important.

JP 2010-46266 A Japanese translation of PCT publication No. 2004-510996 Japanese Patent Laid-Open No. 02-132102

However, as a result of studies by the present inventors, even with the conventional orthodontic adhesives disclosed in Patent Documents 1 and 2, etc., the removal of excess adhesive and the cutting ability of the cured body are insufficient. It was. In addition, in various intraoral adhesive materials used for purposes other than orthodontic purposes disclosed in Patent Document 3 and the like, the material composition and the like are optimized so that the characteristics according to the purpose of use can be exhibited. Therefore, it cannot be used at all as an orthodontic adhesive in the first place. The present invention has been made in view of the above circumstances, and the problem to be solved by the present invention is that, when used for a series of orthodontic treatments using orthodontic members, the removal of excess adhesive and An object of the present invention is to provide an orthodontic adhesive having excellent curability of a cured body and an orthodontic adhesive kit using the same.

As a result of intensive studies to overcome the above technical problems, the present inventors combined a specific amount of a plurality of types of filler components having different particle diameters, and when this was added to the polymerizable monomer component, an excess adhesive material The present invention has been completed by finding that it is an orthodontic adhesive having excellent removability and cutting ability of the cured product.

That is, the orthodontic adhesive of the present invention has an average primary particle size of 0.07 to 0.6 μm, and is 10 to 35% by mass of an inorganic filler component (A1) that is a spherical or substantially spherical particle, In addition, 250 to 750 parts by mass of the filler (A) containing 65 to 90% by mass of the filler component (A2) having an average particle size of 0.7 to 35 μm, and 100 parts by mass of the polymerizable monomer (B). Part and a polymerization initiator (C) 0.01 to 10 parts by mass, and 60% by mass or more of the filler component (A2) is composed of particles having a Vickers hardness HV of less than 750 It is a material component (A3).

The orthodontic adhesive kit of the present invention includes the orthodontic adhesive of the present invention and a tooth surface pretreatment agent.

In the orthodontic method of the present invention, after the orthodontic adhesive material of the present invention is supplied to the adhesion site between the tooth and the orthodontic member, the excessive orthodontic adhesion present in and near the adhesion site. A surplus adhesive removing step for removing the material, an adhering step for adhering the tooth and the orthodontic member by polymerizing and curing the orthodontic adhesive remaining in the adhesion site, and a tooth bonded and fixed to the tooth After removing the orthodontic member from the tooth, at least a cured body removing step of cutting and removing the cured body of the orthodontic adhesive remaining on the surface of the tooth.

The orthodontic adhesive of the present invention has both the ability to remove excess adhesive and the cutting ability of the hardened body by blending a plurality of filler components at a specific ratio. Filler component having an average primary particle size of 0.07 to 0.6 μm and a spherical or substantially spherical particle and a Vickers hardness HV of less than 750 particles of 60% by mass or more and an average particle size of 0.7 to 35 μm By blending the filler (A) containing (A2) with the polymerizable monomer (B) and the polymerization initiator (C), the surgeon can easily remove the excess adhesive, The burden on orthodontic treatment is reduced. Further, the hardened body has good cutting properties, and it is easy to remove the hardened body when the orthodontic member is dropped during the orthodontic treatment or at the end of the treatment.

Therefore, the orthodontic adhesive of the present invention and the orthodontic adhesive kit using the orthodontic adhesive can be suitably used for bonding a living hard tissue such as a tooth to an orthodontic member. Thus, a series of orthodontic treatments conventionally performed can be performed more easily.

The greatest features of the orthodontic adhesive of this embodiment are the ease of removal of excess adhesive when the orthodontic member is mounted on the tooth surface, and the remaining when the orthodontic member is removed. It is in the point which makes the cutting property of the hardening body to make compatible. In order to make these characteristics compatible, in the orthodontic adhesive of this embodiment, the filler component (A), the polymerizable monomer (B), and the polymerization initiator (C) are contained in a predetermined ratio. It is blended with. That is, the orthodontic adhesive of the present embodiment has an average primary particle size of 0.07 to 0.6 μm, and is 10 to 35% by mass of the inorganic filler component (A1) that is spherical or substantially spherical particles. And 250 to 750 parts by mass of a filler (A) containing 65 to 90% by mass of a filler component (A2) having an average particle size of 0.7 to 35 μm, and 100% of the polymerizable monomer (B). Part of the filler component (A2) is composed of particles having a Vickers hardness HV of less than 750, including 0.01 part by weight and 0.01 to 10 parts by weight of a polymerization initiator (C). It is a filler component (A3).

The orthodontic adhesive of the present embodiment combines the inorganic filler component (A1), the filler component (A2), and the filler component (A3) which is a constituent component of the filler component (A2) as essential components. ing. For this reason, the orthodontic adhesive of this embodiment is accompanied by operational problems such as poor removability and poor machinability in a series of orthodontic treatments like conventional orthodontic adhesives. Without being used for orthodontic treatment.

Further, the inorganic filler component (A1) has a smaller particle diameter than the filler component (A2), and the shape thereof is spherical or substantially spherical. When the filler (A) is composed of only the filler component (A2) having a particle size larger than that of the inorganic filler component (A1), the filler (A) and the polymerizable monomer (B) are mixed. The unity becomes worse and the filling rate of the filler (A) cannot be increased. However, by filling the gap between the filler component (A2) having a large particle size so that the inorganic filler component (A1) having a small particle size is filled, the filling rate of the filler (A) as a whole is increased and good. An orthodontic adhesive material with a simple operational feeling can be obtained. Moreover, although the machinability of a hardening body improves because the shape of an inorganic filler component (A1) is spherical shape or substantially spherical shape, sufficient machinability may not be obtained only by it. Therefore, in order to further improve the machinability, it is preferable that part or all of the filler component (A2) is occupied by the filler component (A3) having a relatively low Vickers hardness HV. Thereby, it is possible to achieve both good removability of the excess adhesive and machinability of the cured body.

In addition, in order to improve the removability of excess adhesive material, it is necessary to make the filler composition with less stringing. According to the study by the present inventors, it becomes easy to draw a string by adding a lot of fine particles in the orthodontic adhesive. In order to make stringing difficult, it is effective to increase the proportion of large particles in the entire filler used. On the other hand, when the filler particles become large, the orthodontic adhesive is cured. Hardened body becomes hard and machinability worsens. That is, when the blending amount of small particles is increased in order to improve the machinability, stringing starts to occur and the removability deteriorates. That is, there is a trade-off relationship between the ability to remove excess adhesive and the machinability of the cured body, and it is essentially difficult to achieve both.

In addition, the present inventors also examined conventional orthodontic adhesives disclosed in Patent Documents 1 and 2. For example, the orthodontic adhesive disclosed in Patent Document 1 has a primary particle size of about 0.1 μm for large particles having an average particle size of 0.5 μm or more in order to improve stringing and cutting properties. A large amount of fumed silica having a minute particle size of 5 to 30 nm (10 to 50% by mass in the total filler) is blended. However, the orthodontic adhesive disclosed in Patent Document 1 has a problem that the paste property of the orthodontic adhesive before curing tends to be hard and is difficult to apply to the orthodontic member. Also, when removing the entire surplus adhesive with a relatively wide tip, it is excellent in removability, but if you try to remove the surplus adhesive by cutting off the surplus adhesive with a needle-like instrument, the thixotropy is reduced. It turned out that it became string-like and it was difficult to remove the excess adhesive.

On the other hand, Patent Document 2 exemplifies an orthodontic adhesive using about 1.7 g of fumed silica (aerosil silica) and 105 g of quartz filler as fillers. With such an orthodontic adhesive with an overwhelmingly large proportion of quartz, the removal of excess adhesive before curing is good, but the machinability of a cured product obtained by curing the orthodontic adhesive is not good. It turned out to be sufficient.

Therefore, the present inventors have examined the blending ratio, particle size, hardness, etc. of each filler component constituting the filler as described below in consideration of the above points.

<Inorganic filler component (A1)>
The inorganic filler component (A1) has an average particle diameter of 0.07 to 0.6 μm, and any known inorganic particles having a spherical or substantially spherical shape can be applied without particular limitation. As the material of the inorganic particles, a) an oxide, b) a halide or c) a sulfate selected from periodic groups I, II, III, and IV, a transition metal, or d) a) to c). ) Or a mixture salt of e) a) to c), and the like. Specifically, a single oxide or a complex oxide of a metal such as silicon, titanium, aluminum, zirconium, tin, or a semimetal, can be given. As the composite oxide, those containing alkali metal or alkaline earth metal such as sodium, potassium, magnesium and calcium are also suitable. Among these, silicon is a single oxide or a composite oxide containing silicon as a constituent element (hereinafter referred to as “silicon-based”) because of its excellent chemical stability and easy surface treatment with a silane coupling agent. (Sometimes referred to as "oxide"). In addition, the refractive index of the inorganic particles is not particularly limited, but it is not aesthetic if the color tone of the cured body of the orthodontic adhesive between the tooth and the orthodontic member is significantly different from the color tone of the tooth. For this reason, those in the range of 1.4 to 1.7 possessed by general dental inorganic fillers are preferred.

More specific examples of silicon-based oxides include silicas such as quartz, precipitated silica and sol-gel silica; silica-titania, silica-zirconia, silica-barium oxide, silica-lanthania, silica-alumina, silica-calcia, silica -Strontium oxide, silica-magnesia, silica-titania-sodium oxide, silica-titania-potassium oxide, silica-zirconia-sodium oxide, silica-zirconia-potassium oxide, silica-alumina-sodium oxide, or silica-alumina-potassium oxide And the like. Among them, silica, silica-zirconia, and silica-titania are desirable for dental use from the viewpoint of refractive index. These can be used alone or in admixture of two or more.

The method for synthesizing the inorganic particles mentioned above is not particularly limited as long as the average particle diameter of the obtained particles is 0.07 to 0.6 μm, and is spherical or substantially spherical, and the sol-gel method, precipitation method, melting method, Examples include a combustion method. Among them, the sol-gel method and the combustion method, which are easily obtained industrially, are suitable as methods for obtaining spherical or substantially spherical particles.

Further, the inorganic filler component (A1) that has been surface-treated with a surface treatment agent such as a silane coupling agent can be used. The surface treatment improves the compatibility with the polymerizable monomer (B) in the orthodontic adhesive, and the inorganic filler component (A1) and the filler component (A2) with respect to the polymerizable monomer (B). The total mass can be increased, that is, the filling rate can be increased. Thereby, the mechanical strength and water resistance of the cured body can be improved.

Surface treatment agents include methyltrimethoxysilane, methyltriethoxysilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltriacetoxysilane, vinyltris (β- Methoxyethoxy) silane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltriethoxysilane, γ-methacryloyloxypropyltris (β-methoxyethoxy) silane, γ-chloropropyltrimethoxysilane, γ-chloropropylmethyl Dimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexane ) Ethyl trimethoxysilane, N- phenyl--γ- aminopropyltrimethoxysilane, etc. hexamethyldisilazane is preferably used.

The particle diameter of the inorganic filler component (A1) is represented by the average primary particle diameter of a plurality of particles, and the average primary particle diameter of the inorganic filler component (A1) is 0.07 to 0.6 μm. The average primary particle size needs to be 0.07 to 0.6 μm, but the individual particle size is not necessarily 0.07 to 0.6 μm. When the average primary particle size is less than 0.07 μm, the viscosity of the paste-like orthodontic adhesive is increased, and the removal property of the excess adhesive is deteriorated. On the other hand, when the average primary particle diameter exceeds 0.6 μm, the orthodontic adhesive is not well-organized, and the applicability and adhesion to the orthodontic member are deteriorated. Moreover, when an inorganic filler component (A1) remove | deviates from the said range, it becomes impossible to make the filling rate of the whole filler (A) high. From the viewpoint of better removal of excess adhesive and adhesion to the orthodontic member, the average primary particle diameter of the inorganic filler component (A1) is preferably 0.1 to 0.4 μm. . If the average primary particle diameter satisfies the above requirements, the individual primary particles may be agglomerated somewhat. However, it is preferable to exist as independent particles as much as possible. Specifically, the volume ratio of aggregated particles having a particle diameter of 10 μm or more in the total volume of the inorganic filler component (A1) is less than 5% by volume. preferable.

In addition, an inorganic filler component (A1) is comprised from the small particle | grain which fills the clearance gap between the filler components of a big particle among the filler components which comprise a filler (A). In this sense, the inorganic filler component (A1) has the same function as the fumed silica used in the orthodontic adhesive disclosed in Patent Literature 1, but the inorganic filler component ( A1) has a larger particle size. For this reason, in the orthodontic adhesive of this embodiment, the thixotropy is hardly expressed when trying to remove the surplus adhesive by cutting off the surplus adhesive with a needle-like instrument, and the needle-like instrument The removability using is extremely excellent. In addition to this, the paste property of the orthodontic adhesive of the present embodiment before curing is made of particles with relatively small particle diameters that are difficult to harden and are easy to apply to the orthodontic member.

The average primary particle diameter of the inorganic filler component (A1) is determined using a scanning electron microscope. The powder of the inorganic filler component (A1) is observed with a scanning electron microscope, 30 or more particles in the unit visual field are randomly selected, and the primary particle diameter (maximum diameter) is measured. The value obtained by gradually subtracting the total primary particle size by the number of selected particles is defined as the average primary particle size.

Also, the average uniformity was determined for particles (30 or more) photographed with a scanning electron microscope in order to determine the average primary particle size. Here, the uniformity means a value obtained by grading the particle diameter in the direction orthogonal to the maximum diameter of the particles by the maximum diameter, and the average uniformity means an average value of the uniformity. In the present specification, those having an average uniformity of 0.6 or more are called “spherical or substantially spherical”. The average uniformity is more preferably 0.8 or more.

That is, the average homogeneity is determined by observing the powder with a scanning electron microscope, and regarding 30 or more particles in the unit field of view, the number is (n), the maximum particle diameter is the major axis (Li), and the major axis is perpendicular to the major axis. The diameter in the direction to be measured is measured as the minor axis (Bi), and is calculated by the following formula.

Spherical or nearly spherical shape with high homogeneity and 0.07 to 0.6μm inorganic fine particles are blended as inorganic filler component (A1), so that the gap between filler components (A2) blended together is filled with inorganic It will be in the form occupied by the material component (A1). For this reason, machinability at the time of cutting a hardening body with a bar or an engine improves.

Specific surface area measured by the BET method of the inorganic filler component (A1) component is preferably 2.5 ~ ^70m 2 / g, it is more preferably 5 ~ ^45m 2 / g.

<Filler component (A2)>
The shape of the particles of the filler component (A2) is not particularly limited, and any shape such as a spherical shape, a plate shape, a layer shape, a whisker shape, or an indefinite shape is applicable. In addition, any of inorganic particles, organic particles, and organic-inorganic composite particles can be used.

Examples of inorganic particles include crystalline silica such as quartz, cristobalite, tridymite, stishovite, and cosite, amorphous silica, silica-titania, silica-zirconia, silica-barium oxide, silica-lanthania, silica-alumina, Silica-calcia, silica-strontium oxide, silica-magnesia, silica-titania-sodium oxide, silica-titania-potassium oxide, silica-zirconia-sodium oxide, silica-zirconia-potassium oxide, silica-alumina-sodium oxide, or silica -Alumina-potassium oxide or other silica-based composite oxide, based on amorphous silica, Al ₂ O ₃ , B ₂ O ₃ , TiO ₂ , ZrO ₂ , BaO, La ₂ O ₃ , SrO, CaO, P ₂ _5, ceramics and glasses containing such F is illustrated. Examples of the glass include lanthanum glass, barium glass, aluminosilicate glass, strontium glass, soda glass, lithium borosilicate glass, zinc glass, fluoroaluminosilicate glass, borosilicate glass, and bioglass. Besides these, silicates such as talc, mica, zeolite, montmorillonite, hydroxyapatite, alumina, titania, yttrium oxide, zirconia, calcium phosphate, barium sulfate, aluminum hydroxide, sodium fluoride, potassium fluoride, lithium fluoride, Calcium fluoride, ytterbium fluoride, yttrium fluoride, and sodium monofluorophosphate are also preferable.

Organic particles include polymethyl methacrylate, polyethyl methacrylate, polyfunctional methacrylate, methyl methacrylate / ethyl methacrylate copolymer, methyl methacrylate / butyl methacrylate copolymer, methyl methacrylate / styrene copolymer, methyl methacrylate / ethylene glycol A methacrylate copolymer, a methyl methacrylate / triethylene glycol dimethacrylate copolymer, or a copolymer of methyl methacrylate and a butadiene monomer can be used. Moreover, a crosslinked polymer obtained by copolymerizing a polyfunctional polymerizable monomer with these polymers can also be used. Further, a mixture of two or more kinds may be used.

Examples of the organic-inorganic composite particles include those obtained by dispersing the inorganic particles in organic particles and those obtained by coating the inorganic filler with various polymerizable monomers.

These can be used alone or in admixture of two or more.

Among the filler components (A2), amorphous inorganic particles are more preferable from the viewpoint of high mechanical strength and good machinability. In particular, a silica-based composite oxide or amorphous silica is used as a base material. Glasses are the best. In addition, organic-inorganic composite particles in which the amorphous inorganic particles listed above are dispersed are also suitable. Among the organic particles, cross-linked polymers based on polymethyl methacrylate or polyethyl methacrylate are also suitable. It is.

Among the filler component (A2), the inorganic particles are surface treated with a surface treatment agent such as a silane coupling agent, thereby improving the familiarity with the polymerizable monomer (B), and the mechanical properties of the cured body. Strength and water resistance can be improved. The surface treatment may be performed by a known method as described above, and the same silane coupling agent as described above can be used.

The average particle size of the filler component (A2) is 0.7 to 35 μm, preferably 1 to 12 μm, more preferably 1.5 to 5 μm. If the average particle size is less than 0.7 μm, the strength of the cured body of the orthodontic adhesive decreases, which is not preferable. In addition, the viscosity of the orthodontic adhesive is increased, the filling rate cannot be increased, and stringing is facilitated. If the average particle size exceeds 35 μm, the strength of the cured product becomes too high and the machinability of the cured product becomes poor, or the orthodontic adhesive material becomes poor and the removal property of the excess adhesive material becomes poor. In addition, adhesion when the orthodontic adhesive is applied to the orthodontic member and pressed against the tooth surface also deteriorates.

Here, the particle size of the filler component (A2) is the average particle diameter measured by a laser diffraction scattering particle size distribution analyzer, the average particle size corresponds to the median size d ₅₀ in the frequency distribution of volume-based particle .

If the particles used for the filler component (A2) are too hard, when the hardened body on the tooth surface is removed by cutting with a bar or the like, the hardened body cannot be completely removed or the tooth surface is discolored black due to the wear powder of the bar itself. I do. Therefore, it is preferable to use a filler component (A2) that is not too hard.

The ratio (D (A1) / D (A2)) of the average primary particle diameter D (A1) of the inorganic filler component (A1) and the average particle diameter D (A2) of the filler component (A2) is particularly Although not limited, from the viewpoint of increasing the filling rate, it is preferably in the range of 0.002 to 0.3, more preferably in the range of 0.005 to 0.2, and 0.007 to 0.00. A range of 1 is more preferable.

Specific hardness of the particles is preferably a Vickers hardness HV of less than 860, more preferably less than 830, and particularly preferably less than 750. When particles having a Vickers hardness HV of 860 or more are contained in a large amount in the filler component (A2), the machinability of the cured body may be easily lowered. When the particles are prepared by a breakdown method such as pulverization, the Vickers hardness HV of the particles is a plate-like or lump-like measurement sample (usually a measurement sample having a size of 1 mm square or more) before being pulverized into particles. On the other hand, it is calculated from the diagonal length of the depression formed when a load of 100 gf is applied for 30 seconds with a diamond square pyramid indenter. On the other hand, for particles synthesized as a particulate matter by the build-up method, large particles of 1 mm square or more having the same composition as the particles used as the filler component (A2) are synthesized by the same synthesis procedure. Vickers hardness HV is calculated in the same manner as a measurement sample.

<Filler component (A3)>
In the orthodontic adhesive of this embodiment, 60% by mass or more of the filler component (A2) is composed of the filler component (A3) having a Vickers hardness HV of less than 750.

As the filler component (A3), known particles can be applied without particular limitation as long as the particles have a Vickers hardness HV of less than 750. In addition, the Vickers hardness HV of the particles used as the filler component (A3) is preferably 720 or less, and more preferably 700 or less. However, when the Vickers hardness HV is extremely low, the mechanical strength of the cured body may be insufficient. In addition, when the non-crosslinked organic particles are cut with a bar or the like, the non-crosslinked organic particles may melt due to frictional heat and become difficult to grind. Therefore, the Vickers hardness HV is preferably at least 30 or more. Suitable as the filler component (A3) are inorganic oxide particles, organic-inorganic composite particles, cross-linked polymer particles composed of methyl methacrylate or ethyl methacrylate and a polyfunctional polymerizable monomer, among which amorphous inorganic oxide particles Is desirable. In particular, when the shape of the particles used as the filler component (A3) is indeterminate, it is easy to achieve both the ability to remove excess adhesive and the mechanical strength of the cured body. Here, the irregularly shaped particles are particles having corners that do not have a uniform shape, and usually correspond to pulverized particles.

An amorphous inorganic oxide particle having a Vickers hardness HV of less than 750 can be particularly suitably used as the filler component (A3). Examples of inorganic oxides having a low Vickers hardness HV include ordinary glass, lanthanum glass, borosilicate glass, soda lime glass, barium glass, strontium glass, aluminosilicate glass, barium boroaluminosilicate glass, strontium boroaluminosilicate glass, and fluoro In addition to glass such as aluminosilicate glass, calcium fluoroaluminosilicate glass, strontium fluoroaluminosilicate glass, barium fluoroaluminosilicate glass, strontium calcium fluoroaluminosilicate glass, amorphous silica, silica-titania, silica-titania-barium oxide , Silica-zirconia, silica-alumina, silica-titania-sodium oxide, silica-titania-kaliu Oxide, silica - zirconia - sodium oxide, silica - zirconia - potassium oxide, silica - alumina - sodium oxide, silica - alumina - amorphous silicon-based oxides such as potassium oxide can also be used. Calcium fluoride, calcium phosphate, ytterbium fluoride, mica, and the like can also be used. However, even silicon-based oxides having a high content of ceramic components such as zirconia and alumina and having a high Vickers hardness HV are out of the range of the filler component (A3). These can be used alone or in admixture of two or more. Among these, from the viewpoint of photocurability and hardness when blended with a polymerizable monomer, glass is preferable, and fluoroaluminosilicate glass is particularly preferable.

On the other hand, crystalline silicon oxides such as quartz, cristobalite, and tridymite, and ceramic oxides such as alumina and zirconia have high hardness and are not suitable for the filler component (A3).

The mechanical strength and machinability of the cured body of the orthodontic adhesive are obtained by occupying 60% by mass or more of the filler component (A2) with the filler component (A3) having a low Vickers hardness HV of less than 750. It is possible to achieve both. Further, 10-40% by mass (preferably 13-30% by mass) of the filler component (A2) is preferably the filler component (A4) composed of particles having a Vickers hardness of HV760 or more and less than 860. If the filler component (A4) and the filler component (A3) are used in combination as the filler component (A2), it becomes easier to ensure the mechanical strength without impairing the machinability of the cured body. . The filler component (A2) is most preferably composed of only a filler component (A3) having a Vickers hardness HV of less than 750 and a filler component (A4) having a Vickers hardness HV of 760 or more and less than 860. preferable.

In addition to the ease of cutting, the cured body of the orthodontic adhesive of the present embodiment has characteristics that are contrary to the ease of cutting, that is, to the extent that the orthodontic force can be sufficiently applied to the dentition. Mechanical strength that can provide high adhesiveness to the tooth is required. In order to achieve a balance between these two properties, which are completely contradictory in terms of mechanical strength, the bending strength of the cured body is preferably 180 MPa or less, more preferably 160 MPa or less, and even more preferably 140 MPa or less. Further, the lower limit value of the mechanical strength is preferably 80 MPa or more, and more preferably 100 MPa or more. It should be noted that other dental materials used in the oral cavity, such as dental filling and restorative materials, do not require machinability, and thus the bending strength of these hardened bodies is required to be higher. However, such a hardened body having a higher mechanical strength is not suitable for use in orthodontic treatment because the cutting ability is extremely inferior even though a sufficient correction force can be applied to the dentition. However, in the orthodontic adhesive of the present embodiment, 60% by mass or more of the filler component (A2) composed of large-diameter particles that greatly affect the machinability of the cured body, and the Vickers hardness HV is less than 750. The filler component (A3) having a low mechanical strength is occupied. For this reason, in the orthodontic adhesive of the present embodiment, it is possible to achieve both the machinability of the cured body and the application of sufficient orthodontic force to the dentition.

The average particle size of the filler component (A3) is preferably 1 to 12 μm, more preferably 1.5 to 5 μm. Here, the average particle diameter is an average particle diameter measured with a laser diffraction / scattering type particle size distribution meter, and the average particle diameter corresponds to the median diameter d ₅₀ in the volume-based frequency distribution of the particles.

The filler component (A2) component including the filler component (A3) may be composed of two or more components. In this case, the average particle size is calculated by weighted averaging from the average particle size and the blending amount of each component. Is done.

<Other filler components>
The filler (A) used for the orthodontic adhesive of this embodiment includes other fillers that do not fall under any of the filler component (A1), the filler component (A2), and the filler component (A3). Ingredients may be included. In this case, the other filler component is preferably 25% by mass or less, more preferably 10% by mass or less, and particularly preferably 3% by mass or less with respect to the entire filler (A). In the case where a filler component having an average primary particle size of less than 0.07 μm, such as fumed silica, is blended as another filler component, for example, in order to prevent the removability from deteriorating or an orthodontic adhesive In order to prevent the properties before curing from becoming hard, the amount is 5% by mass or less, more preferably 2% by mass or less, and particularly preferably 0.5% by mass or less.

<Filling rate of filler (A)>
Of the filler (A), each of the inorganic filler component (A1), the filler component (A2), and the filler component (A3) which is a constituent component of the filler component (A2) is composed of one kind of component. It may be composed of two or more components. The blending amount of the filler (A) with respect to 100 parts by mass of the polymerizable monomer (B) is in the range of 250 to 750 parts by mass, and preferably in the range of 400 to 650 parts by mass. If the blending amount is less than 250 parts by weight, it is easy to thread, and mechanical strength is not sufficiently obtained. If it exceeds 750 parts by weight, the amount of the filler becomes excessive, the viscosity of the orthodontic adhesive is increased, and the operability is poor. It becomes difficult to push out from the container.

In addition, depending on the composition ratio of each component of the filler (A), the viscosity of the orthodontic adhesive may be different even at the same filling rate, but the viscosity of the orthodontic adhesive suitable for each composition ratio Thus, an optimal filling rate may be selected within the above range.

<Component composition ratio of filler (A)>
The proportion of the inorganic filler component (A1) in the filler (A) is 10 to 35% by mass, preferably 12 to 30% by mass, and particularly preferably 12 to 25% by mass. When the blending ratio exceeds 35% by mass, the hardened material has good machinability, but the viscosity of the orthodontic adhesive becomes high, and the stringing properties appear or become sticky, resulting in poor removal of the excess adhesive. Moreover, since it becomes impossible to make the filling rate of the whole filler (A) high, the mechanical strength of the cured body tends to decrease.

On the other hand, if the blending ratio of the inorganic filler component (A1) to the filler component (A2) is less than 10% by mass, the stringing property will not appear, but the filler component (A2) having a particle size larger than that of the inorganic filler component (A1). ) Increases, the entire cured body becomes hard and the machinability deteriorates. In addition, when the blending ratio of the inorganic filler component (A1) is small, the gap between the filler component (A2) particles is not filled with the inorganic filler component (A1) having a small particle diameter. The unity of the material is deteriorated and the removability is also deteriorated.

The proportion of the filler component (A2) in the filler (A) is 65 to 90% by mass, preferably 75 to 87% by mass. The proportion of the filler component (A3) in the filler component (A2) is 60% by mass or more, preferably 75 to 87% by mass. When the proportion of the filler component (A3) in the filler component (A2) is large, the machinability is improved, but when it exceeds 90% by mass, the mechanical strength is lowered. On the other hand, if the blending ratio of the filler component (A3) is less than 65% by mass, the machinability deteriorates.

<Polymerizable monomer (B)>
In the orthodontic adhesive of the present embodiment, as the polymerizable monomer (B), a known one can be used without particular limitation, for example, a radical polymerizable monomer or a cationic polymerizable monomer is used. it can. When viewed as a dental use, from the viewpoint of polymerization rate, it is preferable to use a radical polymerizable monomer, and more preferably a polyfunctional one. Particularly preferred radical polymerizable monomers are polyfunctional (meth) acrylate polymerizable monomers.

Examples of polyfunctional (meth) acrylate polymerizable monomers include those shown in the following (A) to (C).
(A) Bifunctional polymerizable monomer (I) Aromatic compounds: 2,2-bis (methacryloyloxyphenyl) propane, 2,2-bis [4- (3-methacryloyloxy) -2-hydroxy Propoxyphenyl] propane, 2,2-bis (4-methacryloyloxyphenyl) propane, 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane, 2,2-bis (4-methacryloyloxydiethoxyphenyl) propane 2,2-bis (4-methacryloyloxytetraethoxyphenyl) propane, 2,2-bis (4-methacryloyloxypentaethoxyphenyl) propane, 2,2-bis (4-methacryloyloxydipropoxyphenyl) propane, (4-Methacryloyloxydiethoxyphenyl) -2 (4- Methacryloyloxytriethoxyphenyl) propane, 2 (4-methacryloyloxydipropoxyphenyl) -2- (4-methacryloyloxytriethoxyphenyl) propane, 2,2-bis (4-methacryloyloxypropoxyphenyl) propane, 2,2 -Bis (4-methacryloyloxyisopropoxyphenyl) propane and acrylates corresponding to these methacrylates; methacrylates having -OH groups such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, etc. Alternatively, acrylates having —OH groups corresponding to these methacrylates and fragrances such as diisocyanate methylbenzene and 4,4′-diphenylmethane diisocyanate Diaducts obtained from addition with a diisocyanate compound having a group.

(II) Aliphatic compounds: ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,4- Butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,2-bis (3-methacryloyloxy-2-hydroxypropoxy) ethyl and acrylates corresponding to these methacrylates; 2-hydroxyethyl methacrylate, 2-hydroxypropyl Methacrylate having a —OH group such as methacrylate, 3-chloro-2-hydroxypropyl methacrylate, etc. or corresponding to these methacrylates And acrylates having an -OH group, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diisocyanate methyl cyclohexane, isophorone diisocyanate, methylenebis diadduct and the like obtained from adducts of a diisocyanate compound such as (4-cyclohexyl isocyanate).

(B) Trifunctional polymerizable monomers trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, pentaerythritol trimethacrylate, trimethylolmethane trimethacrylate, and acrylates corresponding to these methacrylates.

(C) Tetrafunctional polymerizable monomers pentaerythritol tetramethacrylate, pentaerythritol tetraacrylate; diisocyanate methylbenzene, diisocyanate methylcyclohexane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, methylenebis (4-cyclohexylisocyanate), 4 Diadduct obtained from an adduct of a diisocyanate compound such as 1,4-diphenylmethane diisocyanate or tolylene-2,4-diisocyanate and glycidol dimethacrylate or glycidol diacrylate.

These polyfunctional (meth) acrylate polymerizable monomers have a cured product having a refractive index (25 ° C.) of usually 1.45 to 1.60, more preferably 1.52 to 1.56. By using the one in the range, it can be easily matched with the color tone of the tooth. Among these, it is preferable to select and use such that the difference becomes small according to the refractive index of the filler (A) to be used. In this case, two or more kinds of polymerizable monomers may be combined and adjusted to a desired refractive index as a whole. By selecting the difference between the refractive index of the cured product of the polyfunctional (meth) acrylate polymerizable monomer and the refractive index of the filler (A), the transparency of the cured product is increased. . In this case, the adhesive portion between the tooth and the orthodontic member can be made more aesthetic, and if the orthodontic adhesive of this embodiment is a photopolymerization type, the photocurability can be increased. It is effective in that the mechanical strength and adhesive strength can be increased.

Furthermore, if necessary, the polymerizable monomer (B) includes methacrylates such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, hydroxyethyl methacrylate, tetrahydrofurfuryl methacrylate, glycidyl methacrylate, and acrylates corresponding to these methacrylates. Monofunctional (meth) acrylate monomers such as the above, and radical polymerizable monomers other than the above (meth) acrylate monomers may be used.

<Polymerization initiator (C)>
What is necessary is just to select suitably the polymerization initiator (C) used for the orthodontic adhesive material of this embodiment according to the objective. The polymerization initiator (C) is classified into a photopolymerization type and a chemical polymerization type.

Examples of the photopolymerization type polymerization initiator include compounds in which the compound itself is decomposed by light irradiation to generate radical species, and known photopolymerization initiator systems composed of a system in which a polymerization accelerator is added thereto.

Compounds that decompose upon light irradiation to produce polymerizable radical species include camphorquinone, benzyl, α-naphthyl, acetonaphthene, naphthoquinone, 1,4-phenanthrenequinone, and 3,4-phenanthrenequinone. Α-diketones such as 9,10-phenanthrenequinone; thioxanthones such as 2,4-diethylthioxanthone; 2-benzyl-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-benzyl- Diethylamino-1- (4-morpholinophenyl) -butanone-1,2-benzyl-dimethylamino-1- (4-morpholinophenyl) -propanone-1,2-benzyl-diethylamino-1- (4-morpholino Phenyl) -propanone-1,2-benzyl-dimethylamino Α-aminoacetophenones such as -1- (4-morpholinophenyl) -pentanone-1,2-benzyl-diethylamino-1- (4-morpholinophenyl) -pentanone; 2,4,6-tris (trichloromethyl) ) -S-triazine, 2,4,6-tris (tribromomethyl) -s-triazine, 2-methyl-4,6-bis (trichloromethyl) -s-triazine, 2-methyl-4, 6-bis (Tribromomethyl) -s-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine 2- (p-methylthiophenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-chlorophenyl) -4,6-bis (tri Chloromethyl) -s-triazine, 2- (2,4-dichlorophenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-bromophenyl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) -s-triazine, 2-n-propyl-4,6-bis (trichloromethyl) -s-triazine, 2- ( α, α, β-trichloroethyl) -4,6-bis (trichloromethyl) -s-triazine, 2-styryl-4,6-bis (trichloromethyl) -s-triazine, 2- [2- (p- Methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, 2- [2- (o-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine 2- [2- (p-butoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, 2- [2- (3,4-dimethoxyphenyl) ethenyl] -4,6- Bis (trichloromethyl) -s-triazine, 2- [2- (3,4,5-trimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, 2- (1-naphthyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-biphenylyl) -4,6-bis (trichloromethyl) -s -triazine, 2- [2- {N, N-bis (2 -Hydroxyethyl) amino} ethoxy] -4,6-bis (trichloromethyl) -s-triazine, 2- [2- {N-hydroxyethyl-N-ethylamino} ethoxy] -4,6-bis (trichloro Romethyl) -s-triazine, 2- [2- {N-hydroxyethyl-N-methylamino} ethoxy] -4,6-bis (trichloromethyl) -s-triazine, 2- [2- {N, N- Trihalomethyl group-substituted s-triazine compounds such as diallylamino} ethoxy] -4,6-bis (trichloromethyl) -s-triazine; diphenyliodonium, bis (p-chlorophenyl) iodonium, ditolyliodonium, bis (p-methoxy) Phenyl) iodonium, bis (p-tert-butylphenyl) iodonium, p-isopropylphenyl-p-methylphenyliodonium, bis (m-nitrophenyl) iodonium, p-tert-butylphenylphenyliodonium, p-methoxyphenylphenyliodonium , P-octylo Cations such as siphenylphenyliodonium, p-phenoxyphenylphenyliodonium, chloride, bromide, benzenesulfonate, p-toluenesulfonate, trifluoromethanesulfonate, tetrafluoroborate, tetrakis (pentafluorophenyl) borate, tetrakis (penta Fluorophenyl) gallate, hexafluorophosphate, hexafluoroarsenate, aryliodonium salts such as salts consisting of anions such as hexafluoroantimonate; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6- Dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide Of acylphosphine oxide derivatives and the like are preferably used, other compounds that form known radical species can be used without any limitation described in Japanese Patent Document · JP 2005-213231.

As the polymerization accelerator, N, N-dimethylaniline, N, N-diethylaniline, N, N-di-n-butylaniline, N, N-dibenzylaniline, N, N-dimethyl-p-toluidine, N , N-diethyl-p-toluidine, N, N-dimethyl-m-toluidine, p-bromo-N, N-dimethylaniline, m-chloro-N, N-dimethylaniline, p-dimethylaminobenzaldehyde, p-dimethyl Aminoacetophenone, p-dimethylaminobenzoic acid, p-dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid amyl ester, N, N-dimethylanthranic acid methyl ester, N, N-dihydroxyethylaniline, N, N -Dihydroxyethyl-p-toluidine, p-dimethylaminophenethyl alcohol p-dimethylaminostilbene, N, N-dimethyl-3,5-xylidine, 4-dimethylaminopyridine, N, N-dimethyl-α-naphthylamine, N, N-dimethyl-β-naphthylamine, tributylamine, tripropylamine , Triethylamine, N-methyldiethanolamine, N-ethyldiethanolamine, N, N-dimethylhexylamine, N, N-dimethyldodecylamine, N, N-dimethylstearylamine, N, N-dimethylaminoethyl acrylate, N, N- Tertiary amines such as dimethylaminoethyl methacrylate, 2,2 ′-(n-butylimino) diethanol, barbituric acids such as 5-butyl barbituric acid, 1-benzyl-5-phenylbarbituric acid, dodecyl mercaptan, Pentaerythritol Rakisu can be mentioned (thioglycolate) mercapto compounds, and the like. In addition, compounds that promote photopolymerization described in JP-A-2005-213231 can be used without any limitation.

The blending amount of the photopolymerization initiator is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the polymerizable monomer (B) used for the orthodontic adhesive of the present embodiment, The amount is preferably 0.1 to 5 parts by mass. When the blending amount of the photopolymerization initiator is less than 0.01 parts by mass, the curability is remarkably lowered. When there is more quantity of a photoinitiator than 10 mass parts, the intensity | strength of a hardening body will fall.

The chemical polymerization initiator consists of a combination of two or more components, and each component is distributed to each packaging of the orthodontic adhesive prepared in two or more packaging, and each packaging is mixed at the time of use ( It generates radicals when they are in contact. For example, organic peroxides / amines, organic peroxides / amines / organic sulfinic acids, organic peroxides / amines / aryl borates, aryl borates / acidic compounds, and barbituric acid derivatives / copper compounds / What consists of various combinations, such as a halogen compound, is mentioned.

Among the chemical polymerization initiators, a chemical polymerization initiator composed of an organic peroxide / amines is preferable because of its high curability and easy handling, and is particularly included in the tooth surface pretreatment agent. Organic peroxides / amines / aryl borates that are highly curable even when in contact with acidic components are preferred. Typical organic peroxides include ketone peroxides such as methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, methylcyclohexanone peroxide, and cyclohexanone peroxide; 2,5-dimethylhexane-2,5-dihydroperoxide Hydroperoxides such as oxide, diisopropylbenzene hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide; acetyl peroxide, isobutyryl peroxide, benzoyl peroxide, decanoyl peroxide, 3, 5, 5- Diacyl peroxides such as trimethylhexanoyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide; di-t-butyl peroxide Id, dicumyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 1,3-bis (t-butylperoxyisopropyl) benzene, Dialkyl peroxides such as 1,5-dimethyl-2,5-di (t-butylperoxy) -3-hexyne; 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 2,2-bis (t-butylperoxy) butane, 2,2-bis (t-butylperoxy) octane, 4,4-bis (t- Peroxyketals such as butylperoxy) valeric acid-n-butyl ester; α-cumylperoxyneodecanoate, t-butylperococineodecane , T-butylperoxypivalate, 2,2,4-trimethylpentylperoxy-2-ethylhexanoate, t-amylperoxy-2-ethylhexanoate, t-butylperoxy-2- Ethylhexanoate, di-t-butylperoxyisophthalate, di-t-butylperoxyhexahydroterephthalate, t-butylperoxy-3,3,5-trimethylhexanoate, t-butylperoxyacetate , T-butylperoxybenzoate, t-butylperoxymaleic acid, and other peroxyesters; di-3-methoxyperoxydicarbonate, di-2-ethylhexylperoxydicarbonate, bis (4-t-butyl) Tilhexyl) peroxydicarbonate, diisopropylperoxydicarbonate , Di -n- propyl peroxydicarbonate, di-2-ethoxyethyl peroxydicarbonate, etc. peroxydicarbonate such as diallyl peroxydicarbonate and the like. Among these organic peroxides, benzoyl peroxide is particularly preferably used from the viewpoint of radical generation ability and stability.

On the other hand, the amines combined with the organic peroxide are not particularly limited, and examples thereof include secondary or tertiary aromatic amines in which an amino group is bonded to an aromatic group such as an aryl group or a pyridyl group. . For example, secondary aromatic amines that can be suitably used include N-methylaniline, N- (2-hydroxyethyl) aniline, N-methyl-p-toluidine, and the like. Examples of the tertiary aromatic amine that can be suitably used include N, N-dimethylaniline, N, N-diethylaniline, N, N-di-n-butylaniline, N, N-dibenzylaniline, N- Methyl-N- (2-hydroxyethyl) aniline, N, N-di (2-hydroxyethyl) aniline, p-bromo-N, N-dimethylaniline, p-chloro-N, N-dimethylaniline, N, N -Dimethyl-p-toluidine, N, N-diethyl-p-toluidine, p-tolyldiethanolamine, N-methyl-N- (2-hydroxyethyl) -p-toluidine, p-dimethylaminobenzaldehyde, p-dimethylaminoacetophenone P-dimethylaminobenzoic acid, p-dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid amyl ester N, N-dimethylanthranic acid methyl ester, p-dimethylaminophenethyl alcohol, N, N-dimethyl-3,5-xylidine, 4-dimethylaminopyridine, N, N-dimethyl-α-naphthylamine, N, And N-dimethyl-β-naphthylamine.

Among these amines, p-tolyldiethanolamine and N, N-dimethyl-p-toluidine are particularly preferably used from the viewpoint of curability.

The aryl borate is a borate compound having 1 to 4 boron-aryl bonds in one molecule, and preferably a borate compound having 3 to 4 boron-aryl bonds in one molecule.

Specifically, salts of borates having 3 or 4 boron-aryl bonds in one molecule, for example, metal salts such as sodium salt, lithium salt, potassium salt, magnesium salt, tetrabutylammonium salt, tetramethylammonium Salts, ammonium salts such as tetraethylammonium salt, tributylammonium salt, triethanolammonium salt, pyridinium salts such as methylpyridinium salt, ethylpyridinium salt, butylpyridinium salt, or methylquinolinium salt, ethylquinolinium salt, butylchi A quinolinium salt such as a norinium salt can be given. Here, as borate compounds having three boron-aryl bonds in one molecule, monoalkyltriphenylboron, monoalkyltris (p-chlorophenyl) boron, monoalkyltris (p-fluorophenyl) boron, monoalkyl Tris (3,5-bistrifluoromethyl) phenyl boron, monoalkyltris [3,5-bis (1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl) phenyl] boron, Monoalkyltris (p-nitrophenyl) boron, monoalkyltris (m-nitrophenyl) boron, monoalkyltris (p-butylphenyl) boron, monoalkyltris (m-butylphenyl) boron, monoalkyltris (p- Butyloxyphenyl) boron, monoalkyltris (m-butyl) Oxy phenyl) boron, monoalkyl tris (p- octyloxyphenyl) boron, a monoalkyl tris (m-octyloxyphenyl) boron can be exemplified. Examples of borates having four boron-aryl bonds in one molecule include tetraphenyl boron, tetrakis (p-chlorophenyl) boron, tetrakis (p-fluorophenyl) boron, tetrakis (3,5-bistrifluoromethyl). Phenylboron, tetrakis [3,5-bis (1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl) phenyl] boron, tetrakis (p-nitrophenyl) boron, tetrakis (m -Nitrophenyl) boron, tetrakis (p-butylphenyl) boron, tetrakis (m-butylphenyl) boron, tetrakis (p-butyloxyphenyl) boron, tetrakis (m-butyloxyphenyl) boron, tetrakis (p-octyloxy) Phenyl) boron, tetrakis (m-octi) It can be exemplified oxyphenyl) boron. In the above borate, alkyl is either n-butyl, n-octyl or n-dodecyl.

Among these aryl borates, a triethanolammonium salt of tetraphenylboron is particularly preferably used from the viewpoint of curability.

In the chemical polymerization initiator composed of organic peroxide / amines, amines are preferably used in an amount of 0.01 to 4 mol, particularly 0.05 to 3 mol, per mol of organic peroxide.

In organic peroxides / amines / aryl borates, amines are used in an amount of 0.01 to 4 mol, particularly 0.05 to 3 mol, per mol of organic peroxide. It is preferably used in an amount of 01 to 3 mol, in particular 0.05 to 2 mol.

The orthodontic adhesive of this embodiment may further contain a polymerization inhibitor as another optional component. A known polymerization inhibitor can be blended without limitation. The blending amount of the polymerization inhibitor is preferably 0.001 to 5 parts by mass, more preferably 0.01 to 3 parts by mass with respect to 100 parts by mass of the polymerizable monomer (B). When the blending amount of the polymerization inhibitor exceeds 5 parts by mass with respect to 100 parts by mass of the polymerizable monomer (B), a curing failure may easily occur when the orthodontic adhesive is cured. .

In addition, the orthodontic adhesive of the present embodiment can contain various additives such as ultraviolet absorbers, dyes, antistatic agents, pigments, fragrances, and the like as necessary.

In the orthodontic adhesive of the present embodiment composed of each component described above, when using a photopolymerization initiator, the orthodontic adhesive of the present embodiment includes a filler (A), a polymerizable single amount. It is preferable to be provided as a photopolymerization type adhesive comprising one agent containing all the components of the body (B) and the polymerization initiator (C). In addition, when a chemical polymerization initiator is used, the orthodontic adhesive of the present embodiment includes the filler (A), the polymerizable monomer (B), and the polymerization initiator (C). It is preferably provided as a chemical polymerization type adhesive consisting of two agents appropriately distributed to one agent and the second agent. In this case, the orthodontic adhesive is used by mixing the first agent and the second agent immediately before use. As the orthodontic adhesive, a photopolymerizable adhesive is more preferable from the viewpoint of simplicity in which an orthodontic member such as a bracket is attached to the tooth surface and the next operation can be started immediately.

<Orthodontic method and orthodontic adhesive kit>
The orthodontic adhesive of the present embodiment described above can be used for a known orthodontic treatment. Here, the orthodontic method according to the present embodiment supplies the orthodontic adhesive according to the present embodiment to the adhesion site between the tooth and the orthodontic member, and then the surplus that exists in and near the adhesion site. To remove the orthodontic adhesive, the surplus adhesive removing step, the adhesive step of bonding the tooth and the orthodontic member by polymerizing and curing the orthodontic adhesive remaining in the bonding site, and the tooth If it includes at least a hardened body removing step of cutting and removing a hardened body of the orthodontic adhesive remaining on the surface of the tooth after removing the orthodontic member fixed by adhesion from the tooth There is no particular limitation.

Here, “removing the orthodontic member bonded and fixed to the tooth from the tooth” in the cured body removing step means that the orthodontic member bonded and fixed to the tooth during the orthodontic treatment is unintentionally dropped. When a drop-off step occurs, and / or when an exfoliation step is performed to intentionally remove the orthodontic member bonded and fixed to the tooth for the next treatment stage or due to the end of treatment. means.

It should be noted that orthodontic treatment is usually performed in the first stage of applying orthodontic force to a badly arranged dentition and correcting the dentition, and in order to retain the tooth until the corrected tooth movement subsides. A second stage of retaining the dentition corrected in the stage. As used herein, the term “orthodontic member” refers to a member that is temporarily bonded and fixed to a tooth using an orthodontic adhesive for the purpose of orthodontic treatment. Although not particularly limited, for example, the orthodontic member used in the first stage can include a wire-mounted member such as an orthodontic bracket or an orthodontic band, and is used in the second stage. Examples of the orthodontic member to be used include a post-correction retainer such as a wire shape or a ribbon shape. In addition, when the orthodontic member is bonded to the tooth, generally, pretreatment of the tooth surface is performed before the orthodontic adhesive is applied to the tooth.

Considering the points described above, it is more preferable that the orthodontic method of the present embodiment is specifically the mode described below. That is, in the first stage of orthodontic treatment, after supplying the orthodontic adhesive of the present embodiment to the adhesion site between the tooth and the wire-attached member, the surplus teeth that exist at and near the adhesion site An excess adhesive removing step (first excess adhesive removing step) for removing the orthodontic adhesive, and a tooth and an orthodontic member by polymerizing and curing the orthodontic adhesive remaining in the adhesion site Adhering step (first adhering step) and attaching orthodontic wire to the wire attached member adhered to the tooth, thereby correcting the dentition by applying an orthodontic force to the dentition. A correction step is preferably performed.

Here, in the first surplus adhesive removing step, the adhesion site is usually formed between the tooth and the wire attached member (adhesion interface). In this case, excessive teeth that are attached to the periphery of the adhesive interface or that are present in the vicinity of the adhesive interface that protrudes from the adhesive interface due to extrusion to the periphery of the orthodontic adhesive that is excessively present at the adhesive interface Mainly remove the orthodontic adhesive. Next, the orthodontic adhesive remaining on the bonding interface is polymerized and cured in the bonding step. At this time, it is particularly preferable to supply the orthodontic adhesive to the adhesion site after the pretreatment step of pretreating the tooth using the tooth surface pretreatment agent. Moreover, after the dentition is sufficiently corrected, a peeling step for peeling the wire attached member from the tooth is performed.

Also, in the second stage of orthodontic treatment, the orthodontic adhesive of this embodiment is supplied to the bonding site between the tooth whose orthodontic has been corrected through the orthodontic step and the post-correcting retainer. After that, the surplus adhesive removal step (second surplus adhesive removal step) that removes the excess orthodontic adhesive existing in and near the adhesion site, and the orthodontic adhesive remaining in the adhesion site It is preferable to carry out an adhesion step (second adhesion step) for adhering the tooth and the orthodontic member by polymerizing and curing the teeth. By performing the second bonding step, the dentition is held by the post-orthodontic holder.

Here, in the second surplus adhesive removal step, for example, (i) when a ribbon-like lingual orthodontic retainer is used as the orthodontic retainer, the bonding site is a tooth and ribbon-like lingual orthodontic retainer. (Adhesive interface). In this case, excessive teeth that are attached to the periphery of the adhesive interface or that are present in the vicinity of the adhesive interface that protrudes from the adhesive interface due to extrusion to the periphery of the orthodontic adhesive that is excessively present at the adhesive interface Mainly remove the orthodontic adhesive. Next, the orthodontic adhesive remaining on the bonding interface is polymerized and cured in the bonding step.

(Ii) When a wire-like orthodontic retainer is used as the orthodontic retainer, after placing the wire-like orthodontic retainer on the tooth surface, the wire-shaped orthodontic retainer and the surrounding tooth surface The orthodontic adhesive of this embodiment is placed so as to cover Therefore, the pile of the orthodontic adhesive material that has been arranged forms an adhesion site. In this case, if the amount of placement is excessive, the excess orthodontic adhesive is removed from the pile of the orthodontic adhesive that has been placed. Next, the orthodontic adhesive remaining in the pile of the orthodontic adhesive deposited in the bonding step is polymerized and cured.

In any case of (i) and (ii), the orthodontic adhesive may be supplied to the adhesion site after the pretreatment step of pretreating the tooth using the tooth surface pretreatment agent. Particularly preferred. In addition, after the dentition is sufficiently retained, a peeling step for peeling the post-correction retainer from the tooth is performed.

Here, in the first and second steps, the hardened body removing step is performed when the dropping step occurs after the bonding step or when the peeling step is performed, the orthodontic adhesive material remaining on the tooth surface. It implements suitably for a hardening object.

In the orthodontic method of the present embodiment, it is preferable to use the orthodontic adhesive of the present embodiment in both the first stage and the second stage, but the present embodiment only in one of the stages. It is also possible to use only the orthodontic adhesive. Further, when the pretreatment step is performed in the first stage and / or the second stage, the orthodontic adhesive kit of the present embodiment including the orthodontic adhesive of the present embodiment and the tooth surface pretreatment agent. It is also suitable to use. The orthodontic adhesive kit of the present embodiment is usually preferably composed only of the orthodontic adhesive of the present embodiment and the tooth surface pretreatment agent. The compositions can be further appropriately combined.

Further, in the bonding step, the orthodontic adhesive according to the present embodiment is appropriately applied to any position on the tooth surface according to the shape and location of the orthodontic member used for the orthodontic treatment. Is done. For example, when an orthodontic bracket is used as the orthodontic member, an orthodontic adhesive is applied to the lip side surface of the tooth. However, in any case, when the cavity generated by the tooth decay is formed on the tooth, the orthodontic adhesive is applied except for the tooth surface in and around the cavity.

<Tooth surface pretreatment agent>
As the tooth surface pretreatment agent used in the pretreatment step, a known tooth surface treatment agent can be appropriately used as long as it contributes to improvement in adhesion between the tooth and the orthodontic member. In addition, a combination of primers, a combination of an etching agent and a self-primer, a self-etching primer, or a combination of a primer and a self-etching primer can be used.

In addition, the pretreatment of the tooth surface is specifically performed as follows. First, in order to adhere an orthodontic member such as an orthodontic bracket to a tooth in general, the following tooth surface pretreatment is performed before applying the orthodontic adhesive to the tooth. Has been done. That is, pretreatment procedures are generally 1) application of an etching agent for etching hard teeth (mainly enamel), and 2) a penetration enhancer called a primer. As a primer application.

As the etching agent, an acid aqueous solution that decalcifies the tooth surface is generally used, and an aqueous solution of phosphoric acid, citric acid, maleic acid or the like is used. The enamel surface is roughened by decalcification.

On the other hand, as the primer, it is said that the orthodontic adhesive needs to penetrate and harden into the fine gaps on the roughened enamel surface, so that it is necessary to use a hydrophilic polymerizable monomer such as hydroxyethyl methacrylate. A polymerizable monomer composition mainly composed of a monomer or an organic solvent is used. The primer itself may or may not contain a polymerization initiator, and any of them can be suitably used. When the primer does not contain a polymerization initiator, the primer can be used in combination with an orthodontic adhesive containing a radical polymerizable monomer, for example. In this case, the polymerizable monomer contained in the primer is polymerized and cured by the action of radicals generated in the orthodontic adhesive during the curing reaction of the orthodontic adhesive applied on the primer. .

After applying the primer, after removing the organic solvent and water by air blow or the like as necessary, the orthodontic member coated with the orthodontic adhesive is pressed against the primer-treated surface. In this state, the orthodontic adhesive is cured. For example, when the orthodontic adhesive is a photo-curing type, the orthodontic adhesive can be photo-cured by light irradiation. At this time, before the curing process, the excess orthodontic adhesive overflowing to the outside of the orthodontic member is appropriately removed before curing.

In addition, a self-etching primer that has been developed for the purpose of exhibiting both a pre-treatment operation using an etching agent and a primer in one step, that is, a deashing function of the etching agent and a function of promoting penetration of the primer. Can also be suitably used. The self-etching primer is usually a polymerizable monomer having a polymerizable monomer, water, an organic solvent or the like as a main component and an acidic group such as a phosphate group or a carboxylic acid group as a part of the polymerizable monomer. Containing. The self-etching primer may also contain a photopolymerization initiator. In addition, after pre-treating a tooth substance with an etching agent, you may process with a self-etching primer next.

Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to these examples.

The various physical property measurement methods in Examples and Comparative Examples described later are as follows.

(1) Vickers hardness HV
For the particles used as the filler component (A2), the Vickers hardness HV of the filler component prepared by the pulverization method was measured as follows. (Ia) That is, when the material to be crushed before pulverization is plate-shaped, it is directly installed on the sample setting part of the microhardness meter, and the diagonal line of the depression formed when a load of 100 gf is applied for 30 seconds with a diamond square quadrangle indenter Vickers hardness HV was calculated from the length. (Ib) When the lump before pulverization is in the form of flakes or particles, the lump of 1 mm square or more is embedded in an immediate polymerization resin, and the embedded lump is polished with a rotary polishing machine to obtain the desired lump The object was exposed, and the Vickers hardness HV was calculated from the diagonal length of the recess formed when a load of 100 gf was applied to the exposed surface (flat surface) with a diamond square pyramid indenter for 30 seconds.

(Ii) On the other hand, the particles synthesized by the build-up method that cannot be crushed were measured by the following method. Large particles of 1 mm square or more having the same composition as the target particles were synthesized by the same synthesis procedure and embedded in an immediate polymerization resin. The embedding is polished with a rotary polishing machine to expose the target particles, and the diagonal length of the depression formed when a load of 100 gf is applied to the surface (flat surface) with a diamond regular quadrangle pyramid indenter for 30 seconds. From the above, Vickers hardness HV was calculated.

In any of the cases (ia), (ib), and (ii), the indentation formed by the indenter is relative to the measurement sample surface region (the surface portion exposed by polishing in (ib) and (ii)). It was formed in a portion excluding the peripheral portion of the measurement sample surface region. Moreover, the measurement measured 4 points | pieces with respect to the same measurement sample, and made the average value Vickers hardness HV. As a measuring apparatus, a micro hardness tester MMT-X7 manufactured by Matsuzawa Seiki was used.

(2) Average particle diameter The method of measuring the average particle diameter of the filler component differs between the filler component (A1) and the filler component (A2). As shown below, for the filler component (A1), the average value when the maximum particle diameter taken with a scanning electron microscope is the primary particle diameter, and for the filler component (A2), the laser diffraction scattering type the particle size d ₅₀ measured by a particle size distribution meter was defined as the average particle diameter. The former is a measurement method when a part of the particles may be aggregated, and the latter is a measurement method in which the aggregation state is reflected.

<Average primary particle size>
Applies to inorganic filler component (A1). The powder is observed with a scanning electron microscope, 30 or more particles in the unit field of view are randomly selected, and the primary particle diameter (maximum diameter) is measured. The value obtained by gradually subtracting the total primary particle size by the number of selected particles is defined as the average primary particle size.

<Average particle size>
Applies to filler component (A2). The particle diameter of a liquid in which particles are dispersed in ethanol at a concentration of 1% by weight and dispersed by ultrasonic irradiation for 10 minutes is measured using a laser diffraction / scattering particle size distribution meter. In the volume-based frequency distribution of the particles, the particle diameter value d _{50 at} which the cumulative frequency is 50% is defined as the average particle diameter (median diameter).

(3) Average uniformity The powder is observed with a scanning electron microscope, and the number (n: 30) of the 30 particles in the unit field of view, the maximum diameter of the particles is the major axis (Li), and orthogonal to the major axis The diameter in the direction to be measured was measured as the minor axis (Bi), and was calculated by the following formula.

(4) Removability of surplus adhesive material The test piece in which the first teeth of the cow were removed within 24 hours after slaughter and the tooth neck was cut was made of 20 mmφ aluminum using a room temperature curing resin (manufactured by Nano Factor Co., Ltd.). The resin was embedded in the ring. The surface of the test piece was cleaned and sufficiently washed with water, and then the adhering water was removed by air blow. Next, the non-cut enamel surface of the bovine teeth was treated with a tooth surface pretreatment agent (a mixture of 40 parts by weight of 2-methacryloyloxyethyl dihydrogen phosphate, 40 parts by weight of isopropyl alcohol and 10 parts by weight of water), and air Alcohol and water were removed by blowing. An appropriate amount of orthodontic adhesive was placed on a metal orthodontic bracket (Microarch Formula R, for medium incisors, product code 921-101R, Tommy Co., Ltd.) and pressed against the tooth surface. Then, the ease of removal when removing the excess adhesive protruding from the interface between the bracket and the tooth with a probe was evaluated.

Here, the excess adhesive was removed by cutting the paste-like excess adhesive along the tip of the probe along the side end surface of the orthodontic bracket with the probe perpendicular to the tooth surface. . At this time, the evaluation of removability when the excess adhesive on one side surface of the orthodontic bracket was removed was evaluated according to the following criteria.
-Judgment criteria-
A: Excess adhesive material does not remain on the tooth surface and can be removed once. B: Excess adhesive material does not remain on the tooth surface and can be removed in 2 to 3 times. C: Excess adhesive material can be removed in 2 to 3 times. Adhering material cannot be completely removed D: Excess adhesive material can be removed 4 times or more, but tooth surface adhering material cannot be completely removed. In the above criteria, “1 time” means that the probe is used for orthodontics. It means the case where the side end surface of the bracket is moved from one end to the other end along one direction, and “twice” means that the probe is moved between one end and the other end of the side end surface of the orthodontic bracket. It means the case of moving back and forth.

(5) Curability of the cured body A test piece obtained by extracting the first teeth of the cow within 24 hours after slaughter and cutting the tooth neck portion is made of a 20 mmφ aluminum ring using a room temperature curing resin (manufactured by Nano Factor Co., Ltd.). Embedded in resin. The surface of the test piece was cleaned and sufficiently washed with water, and then the adhering water was removed by air blow. Next, the non-cut enamel surface of the bovine teeth was treated with a tooth surface pretreatment agent (a mixture of 40 parts by weight of 2-methacryloyloxyethyl dihydrogen phosphate, 40 parts by weight of isopropyl alcohol and 10 parts by weight of water), and air Alcohol and water were removed by blowing. An orthodontic adhesive 0.1 g was applied to the tooth surface and irradiated with light for 10 seconds using a halogen light irradiator (Tokuso Power Light, manufactured by Tokuyama Corporation). The obtained cured product was cut using a carbide bar and a silicone point using a dental engine microengine. The good machinability at the time of cutting was evaluated in four stages according to the following criteria.
-Judgment criteria-
A: Very good machinability (light cutting feeling)
B: Good machinability (permissible cutting feeling)
C: Cutting is possible but black marks remain on the tooth surface D: Cutting performance is poor (cutting feeling is hard and the hand holding the carbide bar and the silicone point becomes painful)

Details and abbreviations of filler components, polymerizable monomers, polymerization initiators and various additives used in Examples and Comparative Examples are as follows.

<Inorganic filler component (A1)>
・ F1:
Silfill NSS-5N (spherical silica manufactured by Tokuyama Corporation, average primary particle size 0.07 μm, specific surface area 50 m ² / g, average uniformity 0.88) is surface-treated with γ-methacryloyloxypropyltrimethoxysilane.
・ F2:
Silica-zirconia (monodispersed sphere, average primary particle size 0.14 μm, specific surface area 25 m ² / g, average uniformity 0.93, silica content 84%) was surface-treated with γ-methacryloyloxypropyltrimethoxysilane. thing.
・ F3:
Excelica SE-1 (Tokuyama spherical silica, average primary particle size 0.2 μm, specific surface area 10 m ² / g, average uniformity 0.80) surface-treated with γ-methacryloyloxypropyltrimethoxysilane.
・ F4:
Surface treatment of S0-C2 (Spherical silica “Admafine” manufactured by Admatechs, average primary particle size 0.5 μm, specific surface area 6.0 m ² / g, average uniformity 0.86) with γ-methacryloyloxypropyltrimethoxysilane What you did.

<Filler component (A2) other than filler component (A3)>
The following F5 to F7 correspond to the filler component (A4).

・ F5:
Silica-zirconia (indefinite shape, average particle size 1.0 μm, Vickers hardness HV: 820) surface-treated with γ-methacryloyloxypropyltrimethoxysilane.
・ F6:
Silica-zirconia (irregular shape, average particle size 4.0 μm, Vickers hardness HV: 810) surface-treated with γ-methacryloyloxypropyltrimethoxysilane.
・ F7:
Silica-zirconia (indefinite shape, average particle size 10.0 μm, Vickers hardness HV: 840) surface-treated with γ-methacryloyloxypropyltrimethoxysilane.

・ F14:
Quartz (irregular shape, average particle size 5μm, Vickers hardness HV: 900)

<Filler component (A3)>
・ F8:
Fluoroaluminosilicate glass (manufactured by Tokuyama Dental Co., Ltd., irregular shape, average particle size 3.0 μm, Vickers hardness HV: 670)
・ F9:
Barium glass (irregular shape, average particle size 5.0 μm, Vickers hardness HV: 730) surface-treated with γ-methacryloyloxypropyltrimethoxysilane.
・ F10:
Soda lime glass (indefinite shape, average particle size 10.0 μm, Vickers hardness HV: 520)
・ F11:
Fluoroaluminosilicate glass (manufactured by Tokuyama Dental Co., Ltd., irregular shape, average particle size 14.2 μm, Vickers hardness HV: 670)
・ F12:
Calcium fluoride (indefinite shape, average particle size 9.2 μm, Vickers hardness HV: 200)
・ F13:
Organic-inorganic composite particles (indeterminate, average particle size 29.2 μm, Vickers hardness HV: 110; a solution in which 1.5 g of Bis-GMA, 1 g of 3G, and 0.013 g of azobisisobutyronitrile were mixed. Then, 7.5 g of filler component F2 was added, kneaded in a mortar, polymerized and cured in a nitrogen atmosphere at 95 ° C. for 1 hour, and the cured product was further pulverized to obtain γ-methacryloyloxypropyltrimethoxysilane. Surface treated with

<Other filler components>
F15: Hydrophobized fumed silica (hydrophobized with monomethyltrichlorosilane, average primary particle size 15 nm, specific surface area 120 m ² / g, bulk density 50 g / L, modified hydrophobicity 47%, Leolosil MT-10, Tokuyama Made)

<Polymerizable monomer (B)>
・ Bis-GMA:
2,2-bis [(3-methacryloyloxy-2-hydroxypropyloxy) phenyl] propane · 3G:
Triethylene glycol dimethacrylate D-2.6E:
2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane UDMA:
1,6-bis (methacrylethyloxycarbonylamino) -2,2,4-trimethylhexane

<Polymerization initiator (C)>
・ CQ:
Camphorquinone (photopolymerization initiator)
DMBE:
N, N-dimethyl p-ethyl benzoate (polymerization accelerator)

<Polymerization inhibitor>
・ BHT:
Dibutylhydroxytoluene

(Production Example 1)
As a polymerizable monomer (B), 3.0 g of Bis-GMA, 2.0 g of D-2.6E, 2.0 g of 3G, and 3.0 g of UDMA were mixed to obtain a polymerization initiator (C). 0.024 g CQ, 0.036 g DMBE were added, and a mixture was further added with 0.01 g BHT. Next, the mixture was stirred until the mixture was uniform to prepare a matrix monomer. Subsequently, 5.3 g of F1 as the inorganic filler component (A1), 24.8 g of F8 as the filler component (A3), and 5.3 g as a filler component (A2) other than the filler component (A3) F6 was weighed, mixed with a matrix monomer, and kneaded to obtain an orthodontic adhesive in which the filling rate of the filler (A) in the orthodontic adhesive was 78%. The ratio of the filler component (A3) in the filler component (A2) was 82% by mass. Table 1 shows the blending ratio of the filler (A), the polymerizable monomer (B), the polymerization initiator (C), and the polymerization inhibitor of Production Example 1.

Example 1
Using the orthodontic adhesive prepared in Production Example 1, the removal of excess adhesive and the cutting ability of the cured body were evaluated. The evaluation results are shown in Table 1.

Moreover, after evaluating the removal property of the excess adhesive material in Example 1, a visible light irradiator (Toxo Power Light, 700 mW / cm ² , Co., Ltd.) was formed from both side surfaces of the orthodontic bracket in pressure contact with the tooth surface. Visible light was irradiated for 5 seconds each by Tokuyama, and the orthodontic adhesive was cured. The bovine teeth to which the orthodontic bracket is bonded are immersed in water at 37 ° C. for 24 hours and then subjected to a shear test using a universal testing machine (Autograph, manufactured by Shimadzu Corporation) at a crosshead speed of 1 mm / min. And the adhesive strength between the non-cut enamel and the orthodontic adhesive was measured. The adhesive strength was 9.2 MPa.

(Production Examples 2 to 26)
Tables 1 and 2 show the compositions of orthodontic adhesives produced according to the production method of Production Example 1.
(Examples 2 to 19)
Regarding the orthodontic adhesives of Production Examples 2 to 19 shown in Table 1, the removal ability of the excess adhesive and the cutting ability of the hardened body were evaluated. The evaluation results are shown in Tables 1 and 2.

(Comparative Examples 1 to 7)
The orthodontic adhesives of Production Examples 20 to 26 shown in Tables 1 and 2 were evaluated for the ability to remove excess adhesive and the cutting ability of the cured product. The evaluation results are shown in Tables 1 and 2.

As shown in Table 2, in Comparative Example 1, if the content of the spherical or substantially spherical inorganic filler component (A1) is too small, the whole orthodontic adhesive is lacking and the removability is poor. Since the ratio of large particles such as (A2) and filler component (A3) increases, the machinability is poor. In Comparative Example 2, if the amount of the spherical or substantially spherical inorganic filler component (A1) is too large, the stringing property appears and the removability is poor. In Comparative Example 3, when the ratio of the filler component (A3) in the filler component (A2) is reduced to 53% by mass, the cured body becomes hard and the machinability deteriorates. In Comparative Example 4 and Comparative Example 5, when a part of the filler component (A2) is replaced with quartz powder F14 having a high Vickers hardness HV, a spherical or substantially spherical inorganic filler component (A1) is included. Also has poor cutting performance. Similarly, in Comparative Example 7, when all of the filler component (A2) is composed only of F6 and F5 having a Vickers hardness HV higher than 750, it contains a spherical or substantially spherical inorganic filler component (A1). Also has poor cutting performance. As is apparent from the results shown in Examples 1 to 19 in Tables 1 and 2, the orthodontic adhesive of the present invention was excellent in removal of excess adhesive and cutting performance.

Comparative Example 6 is a filler and polymerizable monomer composition close to the composition described in Patent Document 3. In Comparative Example 6, the removal performance was good when the excess adhesive material was removed at the tip of the tweezers, which is a tool having a relatively wide tip shape. However, as in Comparative Example 6, it should be removed by cutting with a needle-like tool. Then, the deposit on the tooth surface could not be completely removed, and the remaining removability was C judgment.

Claims

Packing with an average primary particle size of 0.07 to 0.6 μm, spherical or substantially spherical particles, inorganic filler component (A1) 10 to 35% by mass, and an average particle size of 0.7 to 35 μm 250 to 750 parts by mass of the filler (A) containing 65 to 90% by mass of the material component (A2),
100 parts by mass of the polymerizable monomer (B),
Including 0.01 to 10 parts by mass of a polymerization initiator (C),
And the orthodontic adhesive whose 60 mass% or more is a filler component (A3) which consists of particle | grains whose Vickers hardness HV is less than 750 among filler components (A2).
The orthodontic adhesive according to claim 1, wherein 10 to 40% by mass of the filler component (A2) is a filler component (A4) composed of particles having a Vickers hardness HV of 760 or more and less than 860.
The orthodontic adhesive according to claim 1 or 2, wherein the average particle size of the filler component (A3) is 1 to 12 µm.
Including an orthodontic adhesive and a tooth surface pretreatment agent,
The orthodontic adhesive has an average primary particle size of 0.07 to 0.6 μm, and is an inorganic filler component (A1) 10 to 35% by mass, which is a spherical or substantially spherical particle, and an average particle 250 to 750 parts by mass of filler (A) containing 65 to 90% by mass of filler component (A2) having a diameter of 0.7 to 35 μm, 100 parts by mass of polymerizable monomer (B), and polymerization The filler component (A3) comprises 0.01 to 10 parts by mass of the initiator (C), and 60% by mass or more of the filler component (A2) is composed of particles having a Vickers hardness HV of less than 750. ) Orthodontic adhesive kit.