JP2003327504A - Composition for denture base and denture formed by using the same composition and method for adjusting dental occlusion of denture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve difficulty to adjust dental occlusion of dentures and extremely readily and surely carrying out improvement and control of dental occlusion. <P>SOLUTION: The composition for denture base comprises a liquid preparation consisting essentially of a radically polymerizable methacrylate and a powder material consisting essentially of a methacrylate polymer or a copolymer and a radical polymerization initiator, and a heat distortion temperature of a cured product obtained by polymerizing a mixture of the liquid preparation with the powder material is within the range of 25°C to 60°C. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a denture base composition for producing a denture base and a denture molded by using the composition, and further to an artificial tooth for improving the occlusal defect caused in the denture. The present invention relates to a method of adjusting the occlusal relationship.

[0002]

2. Description of the Related Art With the advent of an aging society, the number of patients with complete denture is increasing, and it is considered that this tendency will be further increased with the aging of the population. Against this background, interest in full dentures is increasing, and higher functional standards are being demanded in combination with the improvement of living standards.

On the other hand, however, as is apparent from the rapid increase in sales of denture stabilizers, the number of patients who are fully satisfied with the denture they are using is surprisingly small, and many patients He seems to have some dissatisfaction with his denture. Above all, dissatisfactions such as "pain" and "do not bite" are fatal to the patient, which means that the denture does not fulfill the original function as an artificial organ at all.

There are two possible causes for the denture that does not bite and does not bite, namely poor fitting of the denture and poor occlusion. As long as the reactive acrylic resin is used as the material for the denture base, the shrinkage (polymerization shrinkage + heat shrinkage) accompanying the molding is added, and the molded denture base is necessarily deformed. This leads to poor fitting and occlusion of the denture, resulting in a denture that does not hurt or bite. Among these, the poor compatibility of the mucosal surface of the denture base can be improved by relining the mucosal surface with a lining material for the denture base. Currently, various lining materials that can be directly lining in the oral cavity have been developed, and it is relatively easy and surely possible to improve poor compatibility.

On the other hand, at present, there is no effective means for improving the occlusal defect, and the only method is to carefully adjust the occlusal and gradually correct the occlusal defect within a limited range. This occlusal defect is called a movement of the artificial tooth arranging position that occurs during molding of the denture base and a change in the intermaxillary relationship that occurs during the process of using the denture
It is triggered by two independent factors. Therefore, it is necessary to handle each individually.

As long as a reactive acrylic resin is used as the material for the denture base, the above-mentioned shrinkage accompanies the denture base molding, and the obtained denture base is necessarily deformed. for that reason,
Even if the occlusal relationship was normal at the stage of the wax denture, the artificial tooth arranging position moved due to contraction after the denture base was formed, which caused a deviation in the occlusal relationship, and in some cases, the occlusal relationship with the cusp. Occlusal phase, or occlusal phase and occlusal phase.

If such contact at the occlusal phase occurs even at one place, the occlusal of the denture will stop at that point,
When viewed from the whole of the denture, the occlusal height diameter becomes high and a sufficient fit cannot be obtained, resulting in a deviation. Therefore, when the upper and lower dentures after molding are reattached to the articulator using the split cast method, the incisor guidance nail does not contact the incisor guidance plate,
Depending on the case, a gap of several millimeters may be opened. In particular, if the early contact point generated in the occlusal phase occurs in the distal molar portion near the temporomandibular joint, the occlusal height becomes even higher, and the gap between the incisor guide nail and the incisor guide plate becomes larger.

Such a movement of the artificial tooth arranging position due to the polymerization shrinkage of the resin is unavoidable in the present situation where an acrylic material is used, and recently, some of the features characterized by precision molding have been characterized. Although a molding process has been developed, even if some suppression effect is recognized,
It does not essentially eliminate the movement of artificial teeth.

When a patient uses a denture having such an upper and lower malocclusion, the denture base always moves while pressing on the alveolar ridge due to early contact of the occlusal phase of the artificial tooth. As a result, a "hit" of occurs. In order to correct such problems caused by poor occlusion, we also adopted a method to find the early contact area using articulating paper with the denture still in the oral cavity, and grind that area with an engine bar to adjust the occlusion. Has been done.

However, it is extremely difficult to check the occlusal defect of the denture base only on the mucous membrane having pressure displacement by using only the occlusal paper, and by shaving it away and shaving it repeatedly, Eventually, the original occlusal surface morphology of the posterior tooth may be greatly impaired, and it may become a non-cusp tooth, and there is a risk that the occlusal height may be reduced by deleting too much. In addition to this problem, a factor of displacement of the intermaxillary relationship is added, which makes occlusal adjustment even more difficult.

As a method for solving this problem of occlusal adjustment in the oral cavity, the upper and lower dentures after molding are reattached to the articulator using the split cast method, and occlusal adjustment is performed on the articulator, that is, the early contact site is set. It is also being ground. In this case, the mucosal surface of the denture base is fixed with hard gypsum, so it is possible to eliminate the displacement of the alveolar mucosa and only adjust the occlusal surface, and there is no change in the intermaxillary relationship. By repeating the adjustment carefully until the incisor guide nail comes into contact with the incisor guide plate, accurate cusp fitting can be surely obtained. However, this grinding adjustment requires a great deal of labor, time, skill, and knowledge, and in this case too, the risk of significantly impairing the original occlusal surface morphology of the molars cannot be excluded.

The deviation of the occlusal relationship of the denture may occur due to the displacement of the intermaxillary relationship that occurs during use of the denture, in addition to the movement of the artificial tooth arranging position at the time of molding described above.
The following are possible causes of such displacement. That is, a patient who has been using a denture that does not fit for many years unknowingly shifts his or her jaw position so as to fit the denture that does not fit, which becomes a habitual jaw position and becomes established. When occlusal sampling is performed on such a patient with a wax bank, occlusal sampling is performed with the displaced habitual occlusal position, and a denture is produced based on the occlusal sampling.

However, once a denture with an improved mucosal surface is attached, the denture is maintained and stable. Therefore, while using the denture, it is necessary to gradually bite the jaw in the original normal occlusal position. The interrelationship is corrected, and as a result, a deviation occurs between the original occlusal position of the living body and the cusp-fitting position of the denture. When mastication is performed with this deviation, a lateral force is induced each time an occlusal force is applied, and the denture tries to move horizontally on the alveolar ridge. Due to such lateral movement, the denture is likely to come off, and by moving on the mucous membrane, "rubbing" or "contact" occurs on the mucous membrane,
Appears as pain during occlusion.

Also in this case, it is possible to perform occlusal sampling using the denture, attach it to the articulator via a check bite, and adjust the occlusal on the articulator. But in this case
If the displacement is small, it is possible to improve the occlusal relationship by adjusting the occlusion by cutting, but if the displacement is large, it becomes extremely difficult to obtain a normal occlusal relationship only by cutting, and in the end, The only option is to remove all artificial teeth and re-align them so that they have the correct occlusal relationship. In this case, if the artificial tooth is a ceramic tooth, it can be removed relatively easily,
In the case of a resin tooth or a hard resin tooth that is commonly used, it is extremely difficult to remove it, and eventually the denture must be recreated from the beginning.

[0015]

DISCLOSURE OF THE INVENTION The present invention solves the existing difficulty of occlusal adjustment of a denture, and is capable of extremely easily and surely improving and adjusting the occlusal relationship, and a composition for a denture. An object of the present invention is to provide a denture molded by using the denture and an artificial tooth occlusal relationship adjusting method for the denture.

[0016]

In order to achieve the above object, a denture base composition of the present invention comprises a liquid agent containing a radically polymerizable methacrylic acid ester as an essential component, a methacrylic acid ester polymer or a copolymer. A heat-deformation temperature of a cured product obtained by polymerizing a mixture of the liquid agent and the powder agent, which is composed of a powder and a powder having a radical polymerization initiator as an essential component.
It is characterized by being in the range of 0 ° C. (Claim 1).

It is desirable to add a plasticizer to the liquid agent (claim 2), and the amount of the plasticizer added is preferably 5 to 50% by weight based on the whole liquid agent (claim 3).

A cured product obtained by polymerizing a mixture of the liquid agent and the powder agent is deformed by applying stress in a heated and softened state.
A denture base composition that retains its shape when deformed when cooled to room temperature in that state (claim 4).

A denture base having a shape change rate of 2% or less when the cured product obtained by polymerization is deformed by applying stress in a heated and softened state, and then immersed and stored in water. A composition for use (Claim 5).

The denture of the present invention is obtained by molding the denture base composition according to claim 1, 2, 3, 4 or 5 into at least the artificial tooth side portion of the denture base (claim 6). ).

A denture formed by using the denture base composition on the entire denture base (claim 7).

An artificial tooth occlusal relationship adjusting method for a denture according to the present invention comprises molding the upper and lower denture according to claim 6 or 7 molded using the composition for denture base according to claim 1, 2, 3, 4 or 5. , Is attached to the articulator used during the production of wax dentures using the split cast method, one or both of the upper and lower dentures, after removing from the articulator and heating and softening,
By reattaching to the articulator and pressing the articulator until the incisor guidance nail contacts the incisor guidance plate, one or both positions of the artificial tooth rows of the upper and lower dentures are moved ( Claim 8).

In addition, the upper and lower dentures are attached to an articulator used in the production of a wax denture by using the split cast method, and one or both of the upper and lower dentures are applied with a stress applied to the articulator. This is an adjusting method in which both or both of the artificial teeth of the upper and lower dentures are moved by heating both of them until the incisor guide nail contacts the incisor guide plate (claim 9).

Further, after mounting the upper and lower dentures in which the intermaxillary relationship is misaligned during use on an articulator through a check bite obtained by occlusally taking the upper and lower dentures, together with the check bite After removing one or both of the upper and lower dentures from the articulator, heating and softening,
Immediately reattaching to the articulator, by pressing until the incisor guide nail of the articulator contacts the incisor guide plate, it is an adjusting method for moving one or both positions of the artificial teeth of the upper and lower dentures. (Claim 10).

Further, the upper and lower dentures in which the intermaxillary relationship is misaligned during use are attached to an articulator via a check bite obtained by occlusal sampling using the upper and lower dentures, and the articulator is attached to the articulator. By heating one or both of the upper and lower dentures in a state in which stress for press contact is applied, the position of one or both of the artificial teeth of the upper and lower dentures is adjusted until the incisor guide nail contacts the incisor guide plate. This is an adjusting method of moving (claim 11).

The denture base composition of the present invention having the above-described structure comprises a liquid agent containing a radically polymerizable methacrylic acid ester as an essential component, a methacrylic acid ester polymer or copolymer, and a radical polymerization initiator. A denture base is obtained by filling a mixture with a powder agent as an essential component into a mold according to a conventional method, and polymerizing and curing by means such as heating.

The heat distortion temperature of the cured product of the present invention is 2
Although it is an essential condition that the temperature is 5 to 60 ° C., the temperature range is set to 25 to 60 ° C. If the temperature range is within this range, strength enough to withstand occlusal pressure is obtained even in the oral cavity, Moreover, a sufficiently softened state can be obtained when heated, and the operation of adjusting the occlusal relationship by heating can be easily performed.

If the heat distortion temperature is within this range,
Since the material shows some plasticity in the oral cavity, when a strong stress is applied locally, that part undergoes plastic deformation,
It is possible to gradually reduce the hit.

If the heat deformation temperature of the cured product is lower than 25 ° C., the amount of deformation due to pressurization in the oral cavity becomes remarkably large, and the strength sufficient to withstand the occlusal pressure cannot be obtained. On the other hand, if the heat distortion temperature exceeds 60 ° C,
Even if heated at 00 ° C., a sufficient softened state cannot be obtained, and the stress necessary for deforming under pressure becomes significantly large. In this case, it is possible to increase the softening by raising the temperature further, but it is practically difficult to heat at 100 ° C. or higher, and it also causes material deterioration. Further, when the heat deformation temperature of the cured product becomes high, the plastic deformation due to the stress becomes difficult to occur, so that the relaxation action when partial contact occurs cannot be expected.

The composition of the present invention has a heat distortion temperature of 25 to 60 ° C., so that it can be softened and deformed at a relatively low temperature of 100 ° C. or lower, so that the composition was deformed. It is possible to maintain the deformed shape as it is by cooling to normal temperature in that state. As a result, the position of the artificial tooth of the prepared denture can be arbitrarily moved, and a bad occlusal relationship is extremely simple.
In addition, it is possible to surely improve the condition.

Further, the composition of the present invention is characterized in that, when the composition deformed and adjusted in a softened state is stored in water, the shape after the adjustment is substantially maintained for a long time. That is, even when immersed in water for 1 day and stored, the rate of change in shape is as small as 2% or less. Therefore, even if the denture after the position of the artificial tooth is moved and stored in water without going to bed, there is no fear of gradually returning to the state before the movement. On the other hand, a material with a heat distortion temperature lower than 25 ° C has a large change in shape when stored in water, and can be
% Changes will occur.

Further, the composition of the present invention has a property that even when it is plastically deformed under various conditions, it gradually returns to the shape before deformation at the temperature in the oral cavity. The material of the present composition has a low heat distortion temperature of 25 to 60 ° C., so that it is relatively soft in the oral cavity and has a greater tendency to be plastically deformed by occlusal pressure than other denture base materials. Here, if the material comprising the present composition has a plastic deformability such as wax, the artificial tooth will sink more and more with each occlusion, and the occlusal height will gradually decrease. This is why wax dentures cannot actually be used in the oral cavity.

However, the composition of the present invention acts to always maintain the shape at the time of molding at the temperature in the oral cavity, and even if the composition is deformed by occlusal pressure, it is gradually left unstressed. Try to restore to the original shape. Therefore, there is no concern that it will gradually deform due to stress such as occlusal pressure. On the other hand, such a property means that even when pressure is applied to displace the position of the artificial tooth, it gradually returns to the original state during use in the oral cavity. However, the change in the oral cavity is very slow, and since the artificial tooth constantly fits with the opposing tooth in the oral cavity, the adjusted position of the artificial tooth does not return to the original position.

Since the denture molded by using the composition of the present invention has the characteristics as described above, the occlusal relationship of artificial teeth can be adjusted as follows. Molded by a conventional method, the upper and lower dentures indexed using the split cast method during artificial tooth arrangement, that is, attached to the articulator used during the production of wax dentures, then remove one or both of the upper and lower dentures from the articulator, Immediately after heating and softening, it is reattached to the articulator, and the articulator is pressure-welded until the incisor guiding nail contacts the incisor guiding plate.

In this case, since the denture made of the composition of the present invention becomes considerably soft by heating, the artificial tooth which was in contact at the occlusal phase by pressing is easily moved laterally until the maximum fitting position is reached. Then, the cusp and the pit are fitted. This is because the occlusal surface of the artificial tooth is originally formed so that the cusp of the artificial tooth slides on the occlusal surface and fits with the pit.

By cooling the denture to the normal temperature while keeping the cusp-fitting condition, the softened denture is hardened while the artificial tooth is still moving, whereby the position of the artificial tooth is adjusted correctly. . Even if the prepared denture is stored in water, the position of the moved artificial tooth is maintained as it is for a long period of time, so that it does not return to the state before adjustment during storage in water.

Further, after remounting the molded upper and lower dentures on the articulator by using the split cast method, by heating one or both of the upper and lower dentures in a state in which a stress that presses against the articulator is applied, The position of the artificial tooth can also be adjusted. That is, the artificial tooth of the denture softened by heating gradually moves to the maximum fitting position due to stress, and the incisor guide nail of the articulator comes into contact with the incisor guide plate. For the pressure contact of the articulator, a method of placing a load on the upper part of the articulator, a method of binding the articulator with a rubber band, or the like can be appropriately selected. Various methods can be adopted for heating the denture, such as a method of heating with a dryer, a method of heating in a constant temperature tank, a method of immersing in a constant temperature water tank, a method of heating with a microwave oven, and the method may be appropriately selected.

On the other hand, when the occlusal relationship of the denture used is out of order, the adjustment can be performed as follows. That is, the upper and lower dentures used are attached to the articulator through the check bite obtained by occlusal sampling, and then one or both of the upper and lower dentures are removed from the articulator and immediately heated and softened. After reattaching to the articulator and slightly elevating the incisor guidance nail, press it until the incisor guidance nail of the articulator comes into contact with the incisor guidance plate. Move one or both positions of the dentition.

Also in this case, as described above, the denture can be heated with stress applied to the articulator.
That is, the upper and lower dentures are attached to the articulator, the incisor guiding nail is slightly elevated, and then stress is applied to the articulator so that one or both dentures are heated and softened. Also in this case, the artificial tooth of the denture is gradually moved to the maximum fitting position by heating, and the incisor guide nail of the articulator comes into contact with the incisor guide plate.

As described above, since the heat distortion temperature of the denture prepared by using the composition of the present invention is in the range of 25 to 60 ° C., the artificial tooth arranging position as described above can be adjusted.

On the other hand, with materials other than the composition of the present invention, such adjustment is impossible. That is, when a denture is made of a material having a heat distortion temperature lower than 25 ° C., it is softened sufficiently by heating and the position of the artificial tooth can be easily moved by pressure contact of the articulator, but after the movement, ,
Attempts to gradually return to the original position even at room temperature. Therefore, the position of the adjusted artificial tooth cannot be retained as it is for a long period of time.For example, when the denture is removed at bedtime and immersed / stored in water, the position of the artificial tooth changes the next morning, resulting in occlusal relationship. Goes crazy.

Further, when a denture is made of a material having a heat distortion temperature higher than 60 ° C., even if the denture is heated at 100 ° C., a sufficient softened state cannot be obtained. Therefore, the heated denture is attached to the articulator. However, it becomes impossible to move the artificial tooth to the normal position even if it is pressed.

[0043]

BEST MODE FOR CARRYING OUT THE INVENTION The denture base composition of the present invention comprises a liquid agent containing a radically polymerizable methacrylic acid ester as an essential component, a methacrylic acid ester polymer or copolymer, and a radical polymerization initiator as an essential component. It is composed of a powder agent for use, and a liquid agent and a powder agent are mixed and used.

Examples of the radical-polymerizable methacrylic acid ester which can be used in the liquid agent include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-hydroxyethyl methacrylate and methacrylic acid 2 Examples include monofunctional methacrylates such as ethylhexyl, lauryl methacrylate, cyclohexyl methacrylate, and glycidyl methacrylate. These may be used alone or in combination of two or more, but from the viewpoint of physical properties and operability, it is preferable to use methyl methacrylate as a main component.

The liquid agent of the present invention may contain a plasticizer, and this component acts to lower the heat distortion temperature of the polymerized cured product, and when the material is heated above the heat distortion temperature. It is also effective for softening. Examples of the plasticizer that can be used here include well-known phthalic acid esters and abietic acid derivatives. Specific examples thereof include phthalic acid esters such as butyl phthalate, octyl phthalate, dibutyl phthalate, dioctyl phthalate, and butyl phthalyl butyl glycolate, and hydrogenated esters such as methyl abiate, butyl abiate, and octyl abiate. can give. These may be used alone or in combination of two or more.

The amount added varies depending on the composition of the methacrylic acid ester used, but is 5 to 50 with respect to the total liquid agent.
It is preferably in the range of% by weight. When the amount of the plasticizer added is less than 5%, it is difficult to keep the heat distortion temperature of the polymerized cured product at 60 ° C or lower, and when it is more than 50% by weight, the heat distortion temperature becomes 25 ° C or higher. Will be difficult to do.

In addition to the above monofunctional methacrylate, a polyfunctional methacrylate may be added to the liquid agent of the present invention for the purpose of improving mechanical strength. Examples of this polyfunctional methacrylate are ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1.3-butylene glycol dimethacrylate, 1.6 hexanediol dimethacrylate, polybutylene glycol dimethacrylate, trimethacrylate. Examples include trimethylol propane methacrylate. However, since these polyfunctional methacrylates increase the heat distortion temperature of the polymerized cured product, the addition amount thereof is preferably suppressed to 20% by weight or less based on the whole liquid agent.

Further, a tertiary amine can be added to the liquid preparation of the present invention as a radical polymerization accelerator. This improves the reactivity of the powder-liquid mixture, and makes it possible to polymerize and cure in a shorter time or at a lower temperature. Further, depending on the amount added, it is possible to polymerize and cure at room temperature. Radical polymerization accelerators that can be used for this purpose include tertiary amines such as NN'-dimethylaniline, NN'-diethylaniline, NN'-dimethylparatoluidine and paratolyldiethanolamine. These may be used alone or in combination of two or more.

This radical polymerization accelerator does not necessarily have to be added when the heat polymerization method is adopted, but it is essential when curing at room temperature, and a small amount should be added even when heat curing. Thus, the curing time can be shortened, and for example, it can be cured in a microwave oven. The addition amount of these components varies depending on the type of the methacrylic acid ester used, the addition amount of the radical polymerization initiator described below, and the curing conditions adopted, but is 3% by weight or less based on the total amount of the liquid agent used. It is preferable to set to. Here, the addition amount is 3
When it is more than wt%, the reactivity becomes too high, the operation time at room temperature becomes very short, and the cured product remarkably turns yellow.

In addition, it is preferable to add a radical polymerization inhibitor to the liquid preparation of the present invention for the purpose of preventing radical polymerization reaction during storage. As the radical polymerization inhibitor usable for this purpose, hydroquinone or hydroquinone is used. Examples include monomethyl ether and 2-hydroxy-4-methoxybenzophenone.

Further, an internal lubricant such as silicone oil or liquid paraffin may be added to the liquid agent of the present invention for the purpose of improving releasability. In this case, if the amount of addition is too large, the physical properties of the cured product will be impaired, so it is preferably 5% by weight or less based on the entire liquid agent.

On the other hand, the powder forming the composition of the present invention is
A methacrylic acid ester polymer or copolymer and a radical polymerization initiator are essential components. Examples of the methacrylic acid ester polymer or copolymer that can be used here include homopolymers such as polymethylmethacrylate, polyethylmethacrylate, and polybutylmethacrylate, methylmethacrylate / ethylmethacrylate copolymer, methylmethacrylate / methylmethacrylate / Copolymers such as n-butyl methacrylate copolymers are included. These may be used alone or as a mixture of two or more, but from the viewpoint of operability after mixing the powder and liquid, polymethyl methacrylate, polyethyl methacrylate, methyl methacrylate / methacrylic acid may be used. It is preferable to use an ethyl copolymer as a main component.

There are no particular restrictions on the molecular weight of the polymers or copolymers constituting these powders, and a wide range of molecular weights can be used, but the average molecular weight is in the range of 10,000 to 1,000,000 from the viewpoint of solubility in liquids. Things are suitable. Here, if the average molecular weight is less than 10,000, the solubility in the liquid agent becomes too good, and the time for exhibiting plasticity, that is, the so-called sticky period is shortened, and sufficient time cannot be taken for the material filling operation. On the other hand, if the average molecular weight is more than 1,000,000, the solubility in the liquid agent will be extremely poor, the time required for forming the mochi will be very long, and the working efficiency will be significantly poor. The particle size of the polymer or copolymer is not particularly limited, but the average particle size is preferably in the range of 10 μm to 100 μm from the viewpoint of the mixing property of the powder liquid and the solubility in the liquid agent. Here, if the average particle size of the powder is smaller than 10 μm, the mixing property of the powder liquid is significantly deteriorated, and if the average particle size is larger than 100 μm, the gelling time after mixing the powder liquid becomes very long. , Workability will be hindered.

The radical polymerization initiator which is another essential component of the powder of the present invention includes diacyl peroxide such as benzoyl peroxide and lauroyl peroxide. The addition amount of these radical polymerization initiators depends on the composition of the methacrylate monomer used,
And, depending on the polymerization system used, it is preferably in the range of 0.05 to 5% by weight based on the total amount of the powder used. Here, if the addition amount is less than 0.05% by weight, the polymerization reactivity becomes extremely poor, and predetermined physical properties cannot be obtained under normal curing conditions. On the other hand, even if the addition amount is more than 5% by weight, a sufficient effect cannot be obtained.

The powder of the present invention may be mixed with a filler or various fibers for the purpose of improving mechanical strength and hardness. Examples of the filler include inorganic powders such as glass powder, silica, alumina and silicon nitride, and examples of the fiber include glass fiber, carbon fiber, aramid fiber and the like. It is also possible to mix pigments, dyes, and red fibers and color them appropriately according to the purpose of use.

The composition of the present invention can also be made to have photopolymerizability by blending a photopolymerization initiator with either the liquid or powder. In this case, it is necessary to add the above-mentioned radical polymerization accelerator to the liquid agent of the present invention, but it is possible to significantly increase the degree of polymerization by photopolymerization after room temperature polymerization.

The photopolymerization initiator that can be used here is
Radicals are efficiently generated upon irradiation with visible light, and radical polymerization reactions can be initiated. Examples thereof include chain α-diketone compounds such as benzyl, 2.3-pentanedione, and camphorquinone. Examples thereof include a polynuclear quinone such as a finger ring α-diketone compound, anthraquinone and naphthoquinone, and a polynuclear quinone derivative such as 2-methyl-1.4 naphthoquinone and 1.2-benzanthraquinone.
These may be used alone or in combination of several kinds.

The amount of the photopolymerization initiator added varies depending on the type of the photopolymerization initiator to be used and the amount of the radical polymerization accelerator or radical polymerization initiator described above. It is preferably in the range of 0.01 to 3% by weight. Here, when the addition amount is less than 0.01% by weight, a sufficient photopolymerization reaction does not occur by irradiation with visible light, and even when the addition amount is more than 3% by weight, the accelerating effect is almost unchanged. On the contrary, the yellowing of the material becomes serious, which causes an adverse effect. These photopolymerization initiators may be added to either powders or liquids, but if added, it is necessary to take measures such as placing them in a light-shielding container so that they are not directly exposed to visible light.

The powders and liquids of the present invention are mixed before use, and the mixing ratio is preferably in the range of 0.3 to 1.0% by weight with respect to 1% by weight of the powders. Here, if the amount of the liquid agent is less than 0.3% by weight, it becomes extremely difficult to uniformly mix the powder agent and the liquid agent, and 1.0
When the content is more than the weight%, the fluidity of the mixture becomes too good, and the time until it becomes a mochi becomes considerably long, and the mochi becomes too soft to pressurize sufficiently.

Production of a denture using the composition of the present invention can be carried out according to a conventional method. That is, a wax denture prepared by a conventional method is embedded in a flask, and after pouring, the powder-liquid mixture of the present invention is filled in a mold. Then, it is cured by room temperature polymerization, heat polymerization or the like, and indexed to obtain a denture. When a combined method of photopolymerization is adopted as the polymerization method, after curing by room temperature polymerization, light is irradiated to secondarily cause photopolymerization.

In the case of the same polymerization type, the composition of the present invention can be used for the artificial tooth side portion and the mucosal surface side portion can be combined with a conventional denture base resin. In this case, first, the artificial tooth side is filled with the composition of the present invention and pressed through a polyethylene film. At this time, a spacer corresponding to the floor is installed in the mold on the mucosal surface side. Next, the mold is opened, the polyethylene film is removed, a conventional denture base resin is filled in, and pressure is applied with the spacer removed. Then, the denture is made into a combination by polymerizing and hardening. As described above, by using the conventional resin for the mucosal surface side portion, the mechanical strength and the durability of the denture are improved.

The denture is heated when adjusting the occlusal relationship of the artificial tooth prepared by using the composition of the present invention. The heating temperature can be appropriately set according to the heat deformation temperature of the material. For example, when the heat distortion temperature is as low as about 25 ° C. to 30 ° C., a sufficient softened state can be obtained by heating to about 60 ° C. On the other hand, the heat distortion temperature is 55
If the temperature is as high as 60 ° C to 60 ° C, it is necessary to heat at a high temperature of 90 ° C or higher. The heat distortion temperature is 30
Even more preferably in the range of -50 ° C.

As described above, by producing a denture using the composition of the present invention, it becomes possible to adjust the occlusal relation very easily and surely, and the physiological occlusal position while performing the function. A denture with a well-established relationship is obtained.

[0064]

EXAMPLES Next, specific experimental examples of the composition for denture base and the method for adjusting the occlusal relationship of artificial teeth of the present invention will be shown. However, it is not limited to the experimental example shown here. [Experimental Example 1] (Preparation of liquid agent and powder agent) 35 parts of butylphthalyl butyl glycolate, 30 parts of methyl methacrylate, 20 parts of isobutyl methacrylate, 2-hydroxyethyl methacrylate 1
0 parts, 5 parts of trimethylolpropane trimethacrylate,
0.2 part of NN'-dimethylparatoluidine was placed in a beaker, stirred and mixed for 10 minutes to prepare a liquid preparation.

80 parts of a methyl methacrylate / ethyl methacrylate copolymer having an average particle diameter of 50 μm and an average molecular weight of 300,000 (molar ratio = 3/2), 20 parts of polyethyl methacrylate having an average particle diameter of 30 μm and an average molecular weight of 300,000. Then, 0.5 part of benzoyl peroxide, 0.3 part of camphorquinone, and 0.05 part of red iron oxide were put in a ball mill and mixed for 10 minutes to prepare a powder.

(Measurement of heat distortion temperature) 1 part of the liquid agent and 2 parts of the powder agent are mixed in a polyethylene container, and the mochi-like material is pressed into a mold having an inner size of 127 × 12.7 × 6.4 mm. The mixture was filled and left as it was at 30 ° C. for 30 minutes to cure. Then, the cured test piece was taken out from the mold, and 12
Illumination was carried out for 20 minutes in a visible light irradiator equipped with two 5 W watt halogen lamps. Using the test piece produced in this way, the heat distortion temperature was measured according to the heat distortion temperature measuring method of JISK6717. The results are shown in Table 1.

[0067]

[Table 1]

(Measurement of rate of change during storage in water) A material which was made sticky in the same manner as above was used, and the inner diameter was 12.7 mm and the height was 20.
It was press-fitted into a mold of mm and left for 30 minutes to cure. Then, the cured test piece was taken out from the mold and irradiated with the visible light irradiator for 20 minutes. After measuring the height (A) of this test piece, the test piece was immersed in hot water of 95 ° C. for 5 minutes to be heated, then taken out, immediately pressurized and compressed to a height of 16 mm. After leaving it as it was at room temperature for 10 minutes, the height (B) of the test piece was measured. Then, this test piece was immersed and stored in water at 20 ° C. for 24 hours, and the height (C) of the stored test piece was measured.

The rate of dimensional change during storage in water for 24 hours was calculated from the following equation, and this was used as the rate of change during storage of this material in water. The results are shown in Table 1. Change rate (%) during storage in water = [(CB) / (AB)] x 1
00

(Measurement of Rate of Change When Pressurized at 37 ° C.) The mochi-like material was filled in a mold having an inner diameter of 10.0 mm and a height of 10 mm in the same manner as above and left as it was for 30 minutes. Cured. Then, the cured test piece was taken out from the mold and irradiated with the visible light irradiator for 20 minutes. After measuring the height (D) of this test piece, 2 kg / cm ² in 37 ° C warm water
The compressive stress was applied, the displacement of the height of the test piece at that time was measured with a dial gauge, and the displacement (E) after 7 hours was measured.

The rate of dimensional change when pressed at 37 ° C. for 7 hours was calculated from the following formula, and this was taken as the rate of change of this material when pressed at 37 ° C. The results are shown in Table 1. Change rate (%) at pressurization at 37 ° C = (E / D) x 100

(Measurement of rate of change during pressurization at 95 ° C.) A test piece having a diameter of 10.0 mm and a height of 10 mm was prepared in the same manner as above, and the height (F) thereof was measured. The test piece is immersed in water at 95 ° C for 5 minutes to be heated, then taken out and immediately at room temperature, 2 kg / cm ² Apply the compressive stress of
After standing for 0 minute, the height (G) of the test piece after standing was measured.

From the following equation, the rate of change in height of the test piece when pressed at a temperature of 95 ° C. was calculated, and this was calculated as 95% of this material.
The rate of change at the time of pressurization at ℃. The results are shown in Table 1. Change rate at pressurization at 95 ° C (%) = (G / F) x 100

(Preparation of denture base and occlusal relationship adjustment experiment) Silicone frames for upper and lower edentulous model preparation were mixed with cemented gypsum (New Fuji Rock manufactured by GC Co., Ltd.) at a specified water mixing ratio and injected. Then, a pair of upper and lower working models were prepared. Paraffin wax (made by GC,
Paraffin wax) was used to prepare an occlusal floor, and then it was mounted on an articulator using the split cast method, and hard resin teeth (Endurer, manufactured by Shofu Co., Ltd.) were arranged according to the standard to prepare a wax denture. As a result of checking the contact state of the occlusal surface with an occlusal paper, a normal cusp contact was shown.

Next, a plaster for burial (advertisement made by GC Co., Ltd.)
Embed the wax denture made from stone into the flask.
After immersing and hardening of the plaster for burial, disassemble the flask and wash.
A gypsum negative mold for molding a denture was obtained by brazing. Resin on the plaster surface
After applying a separating agent (GC, AcroSep),
The above-mentioned waxy substance is pressure-filled therein, and 60 kg / cm² so
The final mold was clamped.

After leaving the mold clamped at room temperature for 30 minutes, the burying plaster was destroyed and the denture base that had been polymerized and hardened was taken out in a state of being mounted on a working model. After removing the burrs and the attached gypsum with a technical engine, they were irradiated with light in the light irradiator for 10 minutes while being mounted on the working model. Next, remove the denture base from the working model, this time with the mucosal surface side facing up, 1
It was irradiated with light for 0 minutes. In this way, a set of upper and lower complete dentures was prepared, and the dentures were reattached to the articulator used when the artificial teeth were arranged, that is, when the wax denture was prepared. At this point, the incision guide nail of the articulator was found to be lifted up by 1.3 mm, and when the occlusal surface contact state was checked with the occlusal paper, it did not show the cusp fitting contact as seen in the wax denture. .

The upper and lower dentures attached to the articulator were removed, and each was immersed in water at 80 ° C. After soaking for 5 minutes, the denture was taken out of the water, immediately reattached to the articulator, and pressed until the incisor guide nail came into contact with the incisor guide plate. To keep the pressure, put a rubber band around the articulator,
It was left as it was at room temperature for 30 minutes.

When the rubber band was removed after 30 minutes, the incisor guide nail remained in contact with the incisor guide plate, and when the occlusal contact state was checked with the occlusal paper, the same cusp fitting contact as that of the wax denture was confirmed. Indicated.

(Inspection of Occlusal Relations after Storage in Water) The upper and lower dentures whose occlusal condition was adjusted as described above were removed from the articulator and immersed and stored in water at 20 ° C. for 24 hours. As a result of taking out from water and reattaching it to the above articulator, the incisor guidance nail did not rise, and the contact state of the occlusal surface did not change when checked with an occlusal paper.

[Experimental Example 2] (Preparation of liquid preparation and powder preparation) 30 parts of butylphthalyl butyl glycolate, 30 parts of methyl methacrylate, 15 parts of isobutyl methacrylate, 10 parts of 2-hydroxyethyl methacrylate and 10 parts of trimethylol trimethacrylate. 8 parts of propane, 5 parts of 2-ethylhexyl methacrylate, 2 parts of liquid paraffin and 0.2 parts of NN'-dimethylparatoluidine were placed in a beaker and stirred for 10 minutes.
A liquid agent was prepared by mixing.

85 parts of a methyl methacrylate / ethyl methacrylate copolymer having an average particle diameter of 50 μm and an average molecular weight of 300,000 (molar ratio = 3/2), 15 parts of polyethyl methacrylate having an average particle diameter of 30 μm and an average molecular weight of 300,000. Then, 0.5 part of benzoyl peroxide, 0.3 part of camphorquinone, and 0.05 part of red iron oxide were put in a ball mill and mixed for 10 minutes to prepare a powder.

(Measurement of Heat Deformation Temperature) 1 part of the liquid agent and 2 parts of the powder agent were mixed in a polyethylene container, and a mochi-like material was used to prepare a test piece in the same manner as in Experimental Example 1, and Experimental Example 1
The heat distortion temperature was measured by the same method as described above. The results are shown in Table 1.
Shown in.

(Measurement of rate of change during storage in water) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as described above, and the same method as in Experimental Example 1 was used. The rate of change during storage was measured. The results are shown in Table 1.

(Measurement of Rate of Change When Pressurized at 37 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. So 37
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Measurement of Rate of Change at Pressurization at 95 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. And 95
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Preparation of Denture Base and Experiment for Adjusting Occlusal Relation) Using the material which was made into a mochi in the same manner as above, an upper and lower denture base was prepared in the same manner as in Experimental Example 1 and reattached to the articulator. Uplift of 1.6 mm was observed in the incisor guide nail of the articulator, and when the contact state of the occlusal surface was checked with the occlusal paper, the cusp fitting state as seen in the wax denture was not shown.

After that, when an artificial tooth was adjusted by the same method as in Experimental Example 1, the incisor guidance nail came into contact with the incision guidance plate, and when checked with an articulating paper, the occlusal relationship between the upper and lower dentures was confirmed. Showed a cusp-fitting contact similar to a wax denture.
In this case, heating of the denture base was performed by immersing the denture base in water at 90 ° C.

(Inspection of occlusal relation after storage in water) The upper and lower dentures whose occlusal condition was adjusted as described above were removed from the articulator, and the temperature was maintained at 20 ° C.
It was immersed and stored in the water for 24 hours. As a result of taking out from the water and reattaching it to the above articulator, the incisor guidance nail did not rise, and when checked with an occlusal paper, the contact state of the occlusal surface did not change.

[Experimental Example 3] (Preparation of liquid preparation and powder preparation) 30 parts of methyl methacrylate, 20 parts of butylphthalylbutyl glycolate, 15 parts of isobutyl methacrylate, 13 parts of 2-ethylhexyl methacrylate
Parts, 2-hydroxyethyl methacrylate 10 parts, trimethylolpropane trimethacrylate 10 parts, liquid paraffin 2 parts, NN'-dimethylparatoluidine 0.2 parts are placed in a beaker and stirred for 10 minutes to prepare a liquid agent. did.

90 parts of a methyl methacrylate / ethyl methacrylate copolymer having an average particle diameter of 50 μm and an average molecular weight of 300,000 (molar ratio = 3/2), 10 parts of polyethyl methacrylate having an average particle diameter of 30 μm and an average molecular weight of 300,000. Then, 0.5 part of benzoyl peroxide, 0.3 part of camphorquinone, and 0.05 part of red iron oxide were put in a ball mill and mixed for 10 minutes to prepare a powder.

(Measurement of Heat Distortion Temperature) 1 part of the liquid agent and 2 parts of the powder agent were mixed in a polyethylene container, and a mochi-like material was used to prepare a test piece in the same manner as in Experimental Example 1, and Experimental Example 1
The heat distortion temperature was measured by the same method as described above. The results are shown in Table 1.
Shown in.

(Measurement of Rate of Change during Storage in Water) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as described above, and the same method as in Experimental Example 1 was used. The rate of change during storage was measured. The results are shown in Table 1.

(Measurement of Rate of Change When Pressurized at 37 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. So 37
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Measurement of Rate of Change at Pressurization at 95 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. And 95
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Preparation of Denture Base and Experiment for Adjusting Occlusal Relationship) Using the material which was made into a mochi in the same manner as above, an upper and lower denture base was prepared in the same manner as in Experimental Example 1, and was reattached to the articulator. A 1.7 mm lift was found in the incisor guide nail of the articulator, and when the occlusal surface contact state was checked with an occlusal paper, the cusp fitting contact as seen in the wax denture was not shown.

After that, when an artificial tooth was adjusted by the same method as in Experimental Example 1, the incisor guidance nail came into contact with the incision guidance plate, and when checked with an articulating paper, the occlusal relationship between the upper and lower dentures was confirmed. Showed a cusp-fitting contact similar to a wax denture.
In this case, heating of the denture was performed by immersing it in water at 100 ° C.

(Inspection of occlusal relation after storage in water) Remove the upper and lower dentures, which have been occlusally adjusted as described above, from the articulator, and leave them at 20 ° C.
It was immersed and stored in the water for 24 hours. As a result of taking out from the water and reattaching it to the above articulator, the incisor guidance nail did not rise, and when checked with an occlusal paper, the contact state of the occlusal surface did not change.

Comparative Example 1 (Preparation of Liquid and Powder) 50 parts of butylphthalylbutyl glycolate, 20 parts of methyl methacrylate, 10 parts of isobutyl methacrylate, 2-hydroxyethyl methacrylate 1
0 parts, trimethylolpropane trimethacrylate 10
And 0.2 part of NN'-dimethylparatoluidine were placed in a beaker, stirred and mixed for 10 minutes to prepare a liquid preparation.

70 parts of a methyl methacrylate / ethyl methacrylate copolymer having an average particle diameter of 50 μm and an average molecular weight of 300,000 (molar ratio = 3/2), 30 parts of polyethyl methacrylate having an average particle diameter of 30 μm and an average molecular weight of 300,000. Then, 0.5 part of benzoyl peroxide, 0.3 part of camphorquinone, and 0.05 part of red iron oxide were put in a ball mill and mixed for 10 minutes to prepare a powder.

(Measurement of heat distortion temperature) 1 part of the liquid agent and 2 parts of the powder agent were mixed in a polyethylene container, and a sticky material was used to prepare a test piece in the same manner as in the experimental example 1, and the experimental example 1
The heat distortion temperature was measured by the same method as described above. The results are shown in Table 1.
Shown in.

(Measurement of rate of change during storage in water) A test piece was prepared in the same manner as in Experimental Example 1 by using the material which was mochi-shaped in the same manner as described above, and the same method as in Experimental Example 1 was used. The rate of change during storage was measured. The results are shown in Table 1.

(Measurement of Rate of Change When Pressurized at 37 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. So 37
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Measurement of Rate of Change When Pressurized at 95 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. And 95
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Preparation of Denture Base and Experiment for Adjusting Occlusal Relation) Using the material which was made mochi in the same manner as above, an upper and lower denture base was prepared in the same manner as in Experimental Example 1, and was reattached to the articulator. A lift of 1.4 mm was observed in the incisor guiding nail of the articulator, and when the occlusal surface contact state was checked with the occlusal paper, the cusp fitting contact as seen in the wax denture was not shown.

After that, when an artificial tooth was adjusted by the same method as in Experimental Example 1, the incisor guidance nail came into contact with the incision guidance plate, and when checked with an articulating paper, the occlusal relationship between the upper and lower dentures was found. Showed a cusp-fitting contact similar to a wax denture.
In this case, heating of the denture was performed by immersing it in water at 70 ° C.

(Inspection of occlusal relation after storage in water) Remove the upper and lower dentures, which have been occlusally adjusted as described above, from the articulator, and remove them at 20 ° C.
It was immersed and stored in the water for 24 hours. As a result of taking out from water and reattaching it to the articulator, 0.6
An uplift of mm was observed, and when checked with occlusal paper, early contact points due to contact between the cusp and the occlusal phase were observed in several places.

Thus, this material has a heat distortion temperature of 1
It is extremely low at 2.5 ° C, a sufficiently softened state can be obtained by heating, and the rate of change when pressurized at 95 ° C is as large as 7.00%, so the work of adjusting artificial teeth is extremely easy. On the other hand, the rate of change during storage in water also increases to 6.87%, and the adjusted artificial tooth gradually changes during storage. Also,
The rate of change when pressurized at 37 ° C is as large as 5.50%,
Since it has the property of being prone to plastic deformation due to stress,
Not suitable for use as a denture base.

Comparative Example 2 (Preparation of Liquid and Dust) 45 parts of butylphthalylbutyl glycolate, 25 parts of methyl methacrylate, 10 parts of isobutyl methacrylate, 2-hydroxyethyl methacrylate 1
0 parts, trimethylolpropane trimethacrylate 10
And 0.2 part of NN'-dimethylparatoluidine were placed in a beaker, stirred and mixed for 10 minutes to prepare a liquid preparation.

75 parts of a methyl methacrylate / ethyl methacrylate copolymer having an average particle diameter of 50 μm and an average molecular weight of 300,000 (molar ratio = 3/2), 25 parts of polyethyl methacrylate having an average particle diameter of 30 μm and an average molecular weight of 300,000. Then, 0.5 part of benzoyl peroxide, 0.3 part of camphorquinone, and 0.05 part of red iron oxide were put in a ball mill and mixed for 10 minutes to prepare a powder.

(Measurement of Heat Deformation Temperature) 1 part of the liquid agent and 2 parts of the powder agent were mixed in a polyethylene container, and a mochi-like material was used to prepare a test piece in the same manner as in Experimental Example 1, and Experimental Example 1
The heat distortion temperature was measured by the same method as described above. The results are shown in Table 1.
Shown in.

(Measurement of Rate of Change during Storage in Water) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as described above, and the same method as in Experimental Example 1 was used. The rate of change during storage was measured. The results are shown in Table 1.

(Measurement of Rate of Change When Pressurized at 37 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. So 37
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Measurement of Rate of Change When Pressurized at 95 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as described above, and the same method as in Experimental Example 1 was used. And 95
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Fabrication of Denture Base and Experiment for Adjusting Occlusal Relation) Using the material which was made into a mochi in the same manner as above, an upper and lower denture base was produced in the same manner as in Experimental Example 1, and was reattached to the articulator. The incisor guiding nail of the articulator was found to be lifted by 1.6 mm, and when the occlusal surface contact state was checked with the occlusal paper, it did not show the cusp fitting contact as seen in the wax denture.

After that, when an artificial tooth was adjusted in the same manner as in Experimental Example 1, the incisor guidance nail came into contact with the incision guidance plate, and when checked with an articulating paper, the occlusal relationship between the upper and lower dentures was confirmed. Showed a cusp-fitting contact similar to a wax denture.
In this case, heating of the denture was performed by immersing the denture in water at 80 ° C.

(Inspection of occlusal relation after storage in water) Remove the upper and lower dentures, which have been occlusally adjusted as described above, from the articulator, and remove them at 20 ° C.
It was immersed and stored in the water for 24 hours. As a result of taking it out of water and reattaching it to the articulator, 0.5
An uplift of mm was observed, and when checked with occlusal paper, early contact points due to contact between the cusp and the occlusal phase were observed in several places.

Thus, this material has a heat distortion temperature of 2
As low as 0.5 ° C, a sufficient softened state can be obtained by heating,
Since the rate of change when pressurized at 95 ° C is as large as 5.89%, the adjustment work of the artificial tooth is easy, while the rate of change during storage in water is also as great as 3.26% and the adjusted artificial tooth is Teeth change gradually during storage. Further, the rate of change when pressurized at 37 ° C. is as large as 3.87%, and since it has a property of easily causing plastic deformation, it is not suitable for use as a denture base.

[Comparative Example 3] (Preparation of liquid agent and powder agent) 40 parts of methyl methacrylate, 25 parts of isobutyl methacrylate, 10 parts of butylphthalylbutyl glycolate, 1 part of 2-hydroxyethyl methacrylate
0 parts, trimethylolpropane trimethacrylate 10
Parts, 5 parts of 2-ethylhexyl methacrylate and 0.2 parts of NN'-dimethylparatoluidine were placed in a beaker and placed in a beaker.
A liquid agent was prepared by stirring and mixing for a minute.

85 parts of a methyl methacrylate / ethyl methacrylate copolymer having an average particle diameter of 50 μm and an average molecular weight of 300,000 (molar ratio = 3/2), 15 parts of polyethyl methacrylate having an average particle diameter of 30 μm and an average molecular weight of 300,000. Then, 0.5 part of benzoyl peroxide, 0.3 part of camphorquinone, and 0.05 part of red iron oxide were put in a ball mill and mixed for 10 minutes to prepare a powder.

(Measurement of Heat Deformation Temperature) 1 part of the liquid agent and 2 parts of the powder agent were mixed in a polyethylene container, and a sticky material was used to prepare a test piece in the same manner as in the experimental example 1.
The heat distortion temperature was measured by the same method as described above. The results are shown in Table 1.
Shown in.

(Measurement of Rate of Change When Pressurized at 37 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. So 37
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Measurement of Rate of Change at Pressurization at 95 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 was used. And 95
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Preparation of Denture Base and Experiment for Adjusting Occlusal Relationship) Using the material which was made mochi in the same manner as above, an upper and lower denture base was prepared in the same manner as in Experimental Example 1, and was reattached to the articulator. The incisor guiding nail of the articulator was found to be lifted by 1.6 mm, and when the occlusal surface contact state was checked with the occlusal paper, it did not show the cusp fitting contact as seen in the wax denture.

After that, when the artificial teeth were adjusted in the same manner as in Experimental Example 1, the incisor guide nail did not contact the incisor guide plate and showed a lift of 1.2 mm. Moreover, when checked with an occlusal paper, the occlusal relationship between the upper and lower dentures did not show the occlusal surface contact state as seen in wax dentures. In this case, heating of the denture was performed by immersing it in water at 100 ° C.

Thus, this material has a heat distortion temperature of 6
It is as high as 3.0 ° C, and the rate of change when pressurized at 95 ° C is as small as 0.68%.
Even if heated at ℃, a sufficient softened state was not obtained, and the artificial tooth could not be adjusted sufficiently. The amount of change when pressurized at 37 ° C is as small as 0.42%.
It cannot be expected to have a relaxing effect when hitting partially strongly.

Comparative Example 4 (Preparation of Liquid and Dust) Beaker with 85 parts of methyl methacrylate, 10 parts of 2-hydroxyethyl methacrylate, 5 parts of trimethylolpropane trimethacrylate and 0.2 parts of NN'-dimethylparatoluidine. The mixture was placed in a container and stirred and mixed for 10 minutes to prepare a liquid agent.

95 parts of methyl methacrylate / ethyl methacrylate copolymer having an average particle diameter of 50 μm and an average molecular weight of 300,000 (molar ratio = 3/2), 5 parts of polyethyl methacrylate having an average particle diameter of 30 μm and an average molecular weight of 300,000. Then, 0.5 part of benzoyl peroxide, 0.3 part of camphorquinone, and 0.05 part of red iron oxide were put in a ball mill and mixed for 10 minutes to prepare a powder.

(Measurement of Heat Deformation Temperature) 1 part of the liquid agent and 2 parts of the powder agent were mixed in a polyethylene container, and a sticky material was used to prepare a test piece in the same manner as in the experimental example 1.
The heat distortion temperature was measured by the same method as described above. The results are shown in Table 1.
Shown in.

(Measurement of Rate of Change When Pressurized at 37 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 So 37
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Measurement of Rate of Change at Pressurization at 95 ° C.) A test piece was prepared in the same manner as in Experimental Example 1 using the material which was mochi-shaped in the same manner as above, and the same method as in Experimental Example 1 And 95
The rate of change at pressurization at ° C was measured. The results are shown in Table 1.

(Preparation of Denture Base and Occlusal Relationship Adjustment Experiment) Using the material which was made mochi in the same manner as above, an upper and lower denture base was prepared in the same manner as in Experimental Example 1, and was reattached to the articulator. A lift of 1.8 mm was observed in the incisor guiding nail of the articulator, and when the occlusal surface contact state was checked with the occlusal paper, the cusp fitting contact as seen in the wax denture was not shown.

After that, when an artificial tooth was adjusted by the same method as in Experimental Example 1, the incisor guide nail did not contact the incisor guide plate, and the protrusion of 1.5 mm was shown. Moreover, when checked with an occlusal paper, the occlusal relationship between the upper and lower dentures did not show the occlusal surface contact state as seen in wax dentures. In this case, heating of the denture was performed by immersing it in water at 100 ° C.

Thus, this material has a heat distortion temperature of 7
As is clear from the fact that the temperature is as high as 4.2 ° C and the rate of change when pressurized at 95 ° C is as small as 0.17%,
Even if heated at 100 ° C., a sufficient softened state was not obtained, and the artificial tooth could not be adjusted sufficiently. Also, 37 ° C
The amount of change when the pressure is applied at 0.21% is small, and therefore, it is not possible to expect a relaxation effect when the part is strongly hit.

[Rate of change with respect to heat distortion temperature] FIG. 1: shows the relationship between the heat distortion temperature and the rate of change during storage in water. Fig. 2: Shows the relationship between the heat distortion temperature and the rate of change when heated at 37 ° C. Figure 3: Shows the relationship between the heat distortion temperature and the rate of change when heated at 95 ° C.

[Experimental Example 4] The upper and lower silicone frame for producing an edentulous jaw model was kneaded with super hard gypsum (New Fuji Rock, manufactured by GC Co., Ltd.) at a specified water mixing ratio and injected into a pair of upper and lower parts. A working model was created. A temporary bed is made on each work model with immediate polymerization resin for temporary bed (Kamemizu Chemical Industry Co., Ltd., fit base), and a wax bank is made with paraffin wax (GC company, paraffin wax) to form an occlusal floor. It was made. Then, it was attached to an articulator using a split cast method, and hard resin teeth (Endurer, manufactured by Shofu Co., Ltd.) were arranged according to the standard to prepare a wax denture. As a result of checking the contact state of the occlusal surface with an occlusal paper, a normal cusp contact was shown.

Next, the prepared wax denture was embedded in a flask using a plaster for burial (Adbastone, manufactured by GC). After the plaster for burying was hardened, the flask was disassembled and flowed to form a denture. A plaster negative mold for use was obtained. After applying the resin separating agent (GC, AcroSep) on the plaster surface,
The sticky material used in Experimental Example 2 was filled therein, and a test pressure and mold clamping were performed via a polyethylene film.

In this case, the above-mentioned temporary bed was attached to the mucosal surface of the mold. After leaving the mold closed for 30 minutes, the flask was opened, the polyethylene film was removed, and a conventional denture base resin (Kamemizu Chemical Industry Co., Ltd.,
Unibase), and then test pressure and mold clamping with the temporary bed removed, 60kg / cm ² The final mold was clamped at.

After leaving the mold clamped at room temperature for 30 minutes, the burying plaster was destroyed and the denture base that had been polymerized and hardened was taken out together with the working model. After removing the burr and the attached gypsum with a technical engine, the experimental example 1 was still attached to the working model.
Light irradiation was performed for 10 minutes in the light irradiation device used in 1. Next, remove the denture base from the working model, this time with the mucosal surface side facing up, 1
It was irradiated with light for 0 minutes.

In this manner, a pair of upper and lower dentures having a combination of the artificial tooth side and the original denture base resin on the artificial tooth side were prepared. As a result of reattaching it to the articulator used when arranging the artificial teeth, a 1.3 mm uplift was found in the incisor guide nail of the articulator. It did not show the cusp-fitting contact as it did.

Next, remove the upper and lower dentures attached to the articulator,
Each was immersed in water at 80 ° C. After soaking for 5 minutes,
The denture was taken out from the water, immediately reattached to the articulator, and pressed until the incisor guide nail contacted the incisor guide plate. A rubber band was put around the articulator in order to maintain the pressurized state, and left at room temperature for 30 minutes.

When the rubber band was removed after 30 minutes, the incisor guide nail remained in contact with the incisor guide plate, and when the occlusal contact state was checked with the occlusal paper, the same cusp fitting contact as that of the wax denture was found. Indicated.

As described above, it was possible to adjust the occlusal relationship of the artificial tooth for the combined denture in the same manner as in Experimental Example 1.

[Experimental Example 5] Using the composition of Experimental Example 1, a set of upper and lower dentures was prepared in the same manner as in Experimental Example 1, and the artificial teeth were reattached to the articulator used during the artificial tooth arrangement. At this point, 1.5 mm of lift was found in the incisor guidance nail of the articulator, and when the occlusal surface contact state was checked with articulating paper,
It did not show the cusp-fitting contact as seen on wax dentures.

Next, a rubber band was applied to the articulator to apply a stress for pressure contact, and in that state, it was placed in a constant temperature bath at 90 ° C. and heated. After 30 minutes, when it was taken out from the constant temperature bath, the incisor guide nail was completely in contact with the incisor guide plate. 1 at room temperature
When left for 0 minutes to cool and remove the rubber band,
There was no lifting of the incision guidance nail, and it remained in contact with the incision guidance plate. Moreover, when the occlusal state was checked with an occlusal paper, it showed a cusp fitting contact similar to that of a wax denture.

As described above, it was possible to adjust the occlusal relationship of the artificial teeth even in the method of heating in the pressed state.

[Experimental Example 6] An impression of the upper and lower jaws of a 74-year-old female edentulous patient was taken, and superhard plaster (New Fuji Rock, manufactured by GC Corporation) was injected into the impressions to make a pair of upper and lower works. A model was made. An occlusal bed was prepared for each model according to the standard method, and occlusal sampling was performed using the occlusal bed. Next, a split denture method was used to attach to an articulator, and hard resin teeth (Endurer, manufactured by Shofu Co., Ltd.) were arranged to prepare a wax denture. At this time, when the contact state of the occlusal surface was checked with an occlusal paper, a normal cusp fitting contact was shown.

Next, using a plaster for burial (manufactured by GC Corporation, Adbastone), the prepared wax denture was buried in the flask, and after the burial plaster was hardened, the flask was disassembled,
Flushing was performed to obtain a gypsum negative mold for molding a denture. After applying a resin separating agent (Acrosep manufactured by GC Co., Ltd.) on the plaster surface, the material used in Experimental Example 2 was pressure-filled thereinto, and 6
The final mold clamping was performed at 0 kg / cm ² .

After leaving the mold clamped for 30 minutes at room temperature, the plaster for burying was destroyed, and the denture base that had been polymerized and hardened was taken out in a state of being mounted on the working model. After removing the burr and the attached gypsum with a technical engine, the product was irradiated with light in the light irradiation device used in Experimental Example 1 for 10 minutes while being attached to the working model. Next, the denture base was removed from the working model, and this time, the mucosal surface side was turned up, and light irradiation was performed for 10 minutes. In this way, a pair of upper and lower dentures was prepared, and the dentures were reattached to the articulator used when arranging the artificial teeth. At this point, the incisor guiding nail of the articulator was found to be lifted up by 1.5 mm, and when the occlusal paper contact state was checked with the occlusal paper, it did not show the cusp fitting contact as seen in the wax denture. .

The upper and lower dentures attached to the articulator were removed, and each was immersed in water at 90 ° C. After soaking for 5 minutes, the denture was taken out of the water, immediately reattached to the articulator, and pressed until the incisor guide nail came into contact with the incisor guide plate. A rubber band was put around the articulator in order to maintain the pressurized state, and it was allowed to stand at room temperature for 30 minutes.

When the rubber band was removed after 30 minutes, the incisor guide nail was still in contact with the incisor guide plate. When the occlusal contact state was checked with the occlusal paper, the same cusp fitting contact as that of the wax denture was confirmed. Indicated. Moreover, when the denture thus adjusted for the occlusal relation was mounted in the oral cavity of the patient and the occlusal relation was checked with an occlusal paper, a good cusp fit contact was shown.

After using the upper and lower dentures for one month, the occlusal relation was checked again. As a result, a slight displacement of the lower jaw position was recognized. As a result of checking the contact state of the occlusal surface using the occlusal paper, No cusp fit was shown.

Next, the upper and lower dentures were placed in the patient's oral cavity, occlusal sampling was performed using the dentures, and the dentures were attached to the articulator via a check bite. Only the lower jaw denture was taken out from the articulator and immersed in water at 90 ° C. After immersing for 5 minutes, remove the denture from the water, immediately return it to the articulator, close the articulator with the incision guide nail of the articulator raised by 1.5 mm, and use the incisor guide nail as the incisor guide plate. Pressurized until contact. Put a rubber band around the articulator to maintain pressure,
It was left as it was at room temperature. When the rubber band was removed after 30 minutes, there was no lifting of the incision guiding nail, and it was still in contact with the incision guiding plate. When the upper and lower dentures were taken out of the articulator and placed in the patient's mouth, they showed a good occlusal relationship, and the occlusal contact check was also normal with the occlusal paper.

As described above, even for a denture in which the intermaxillary relationship is distorted during use, it is possible to improve the normal occlusal relationship by adopting the artificial tooth occlusal relationship adjusting method of the present invention. Met.

[0154]

Since the present invention is constructed as described above, it has the following effects. A solution containing a radically polymerizable methacrylic acid ester as an essential component, a methacrylic acid ester polymer or copolymer, and a powder containing a radical polymerization initiator as an essential component, which were obtained by polymerizing a mixture of a liquid and a powder. Since the heat distortion temperature of the cured product is in the range of 25 to 60 ° C, strength enough to withstand occlusal pressure is obtained even in the oral cavity, and a sufficiently softened state is obtained when heated, and the occlusal relationship due to heating Can be easily adjusted.

Further, since it shows a certain degree of plasticity in the oral cavity, when a strong stress is locally applied, that part undergoes plastic deformation and the contact can be gradually relaxed.

Furthermore, it becomes possible to soften and deform at a relatively low temperature of 100 ° C. or lower, and by cooling to normal temperature in the deformed state, the deformed shape can be retained as it is. . This allows
The position of the artificial tooth of the prepared denture can be arbitrarily moved, and it becomes possible to improve a bad occlusion relationship to a normal state extremely easily and surely.

Further, the composition of the present invention is characterized in that, when it is deformed and adjusted in a softened state and stored in water, the shape after adjustment is almost maintained for a long time. Even when immersed and stored in the sun, the rate of change in shape is very small, less than 2%. Therefore, even if the denture after the position of the artificial tooth is moved and stored in water without going to bed, there is no fear of gradually returning to the state before the movement.

Furthermore, the composition of the present invention has the property of gradually returning to the shape before deformation at the temperature in the oral cavity even when plastically deformed under various conditions, and even if deformation due to occlusal pressure occurs. If left unstressed, it will gradually try to restore its original shape and there is no concern that it will deform.

Since the denture molded by using the composition of the present invention has the above-mentioned characteristics, the upper and lower dentures indexed are mounted on the articulator used at the time of producing the wax denture by using the split cast method, After that, remove one or both of the upper and lower dentures from the articulator, heat and soften it, then immediately reattach it to the articulator, and press the articulator until the incisor guide nail contacts the incisor guide plate. The artificial tooth that was in contact with the phase easily moves laterally until it reaches the maximum fitting position and fits at the cusp and the pit, and the position of the artificial tooth is adjusted correctly. Even if the prepared denture is stored in water, the position of the moved artificial tooth is maintained as it is for a long period of time, so that it does not return to the state before adjustment during storage in water.

After the upper and lower dentures after molding are reattached to the articulator using the split cast method, one or both of the upper and lower dentures are heated under a stress applied to the articulator. The position of the artificial tooth can also be adjusted.

Further, when the occlusal relationship of the denture in use is distorted, the upper and lower dentures in use are attached to an articulator through a check bite obtained by occlusal sampling, Then, remove one or both of the upper and lower dentures from the articulator, heat and soften it, then immediately reattach it to the articulator, and press it until the incisor guidance nail of the articulator comes into contact with the incisor guidance plate. It is possible to move one or both positions of the artificial tooth rows of the upper and lower dentures to the fitting position.

Further, upper and lower dentures are attached to the articulator, stress is applied to the articulator so as to press it, one or both of the dentures is heated and softened, and the artificial tooth of the denture is maximally fitted by heating. You can gradually move to the position.

By preparing a denture using the composition for denture base of the present invention, the adjustment of the occlusal relationship can be performed very easily and surely.

[Brief description of drawings]

FIG. 1 is a relationship diagram between a heat distortion temperature and a rate of change during storage in water.

FIG. 2 is a diagram showing the relationship between the heat distortion temperature and the rate of change when heated at 37 ° C.

FIG. 3 is a relationship diagram between a heat distortion temperature and a rate of change when heated at 95 ° C.

Claims (11)

[Claims] 1. A mixture of a liquid agent and a powder agent, which comprises a liquid agent containing a radical-polymerizable methacrylic acid ester as an essential component and a powder agent containing a methacrylic acid ester polymer or copolymer and a radical polymerization initiator as an essential component. A composition for denture base, characterized in that the cured product obtained by polymerizing the above has a heat distortion temperature in the range of 25 to 60 ° C. 2. The denture base composition according to claim 1, wherein a plasticizer is added to the liquid agent. 3. The addition amount of the plasticizer is 5 to 5 with respect to the whole liquid agent.
The denture base composition according to claim 2, wherein the composition is 0% by weight. 4. A cured product obtained by polymerization is deformed by applying stress in a heated and softened state, and when cooled to room temperature under the state, the deformed form is retained as it is. The denture base composition according to claim 1, 2 or 3. 5. A cured product obtained by polymerization is characterized by having a shape change rate of 2% or less when immersed in water after being deformed by applying stress in a heated and softened state. The composition for denture base according to claim 1, 2 or 3. 6. A denture, characterized by being formed by using the composition for denture base according to claim 1, 2, 3, 4 or 5 for at least an artificial tooth side portion of a denture base. 7. A denture, characterized by being formed by using the composition for denture base according to claim 1, 2, 3, 4 or 5 on the entire denture base. 8. An upper and lower denture according to claim 6, which is formed by using the composition for denture base according to claim 1, 2, 3, 4 or 5, and a wax denture is produced by using a split cast method. Attached to the articulator used at the time, remove one or both of the upper and lower dentures from the articulator to heat and soften it, then reattach it to the articulator, and the incisor guide nail contacts the incisor guide plate. By pressing the articulator until
An artificial tooth occlusal relationship adjusting method for a denture, characterized in that one or both positions of the artificial tooth rows of the upper and lower dentures are moved. 9. An upper and lower denture according to claim 6 or 7 formed by using the composition for denture base according to claim 1, 2, 3, 4 or 5, and a wax denture preparation using a split cast method. Attached to the articulator used at the time, heating one or both of the upper and lower dentures with the stress applied to the articulator in pressure contact until the incisor guidance nail contacts the incisor guidance plate. An artificial tooth occlusal relationship adjusting method for a denture, characterized in that one or both positions of the artificial teeth of the upper and lower dentures are moved. 10. The artificial denture according to claim 6 or 7 in which the intermaxillary relationship is misaligned during use, and is attached to an articulator through a check bite obtained by occlusal measurement using the upper and lower dentures. After that, one or both of the upper and lower dentures together with the check bite are removed from the articulator, heated and softened, and immediately reattached to the articulator. The artificial tooth occlusal relationship adjusting method for a denture, characterized in that one or both positions of the artificial teeth of the upper and lower dentures are moved by pressing until they come into contact with. 11. The upper and lower dentures according to claim 6 or 7 in which the intermaxillary relationship is distorted during use, and attached to an articulator through a check bite obtained by occlusal sampling using the upper and lower dentures. Then, in a state in which stress for press-contacting the articulator is applied, by heating one or both of the upper and lower dentures, the artificial teeth of the upper and lower dentures until the incisor guide nail contacts the incisor guide plate. An artificial tooth occlusal relationship adjusting method for a denture, which comprises moving one or both positions.