JPH0310604B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a soft denture base lining material. More specifically, the present invention relates to a soft denture base lining material suitable for the direct method, which is characterized by containing a photosensitizer. Prior Art Various methods have been tried in the past to alleviate the occlusal pressure applied to the mucosal surface of the denture base by bonding a lining material to the denture base, but none have been satisfactory. In order to solve this problem, the present inventors have previously invented a denture base lined with soft fluorine resin (Japanese Patent Application Laid-open No. 55-21919, Japanese Patent Application No. 58-17212, (Sho 59-394). In particular, Patent Application No. 59-394 succeeded in providing a denture base lining material that facilitated the lining's operability and had ideal viscoelasticity, contributing to relieving the pain of many complete denture patients. . It was thought that if this was further developed and this material with excellent physical properties could be applied to a direct lining material that is pressed directly into the oral cavity, the lining technique would be significantly simplified. That is, conventionally, the lining material was thermally polymerized at the same time as the denture base was polymerized due to the presence of organic peroxide molded in the plaster mold (indirect method). On the other hand,
The direct method is a method in which a paste or putty-like lining material is piled up on the denture base, inserted into the patient's mouth, the shape of the mucosal surface is copied in the same manner as an impression is taken, and the material is left to solidify. In order to carry out such a direct method, the lining material must be soft during operation, rapidly solidify after being pressed against the mucous membrane, and have appropriate viscoelasticity. . There are various denture base lining materials used in the direct method, but none have yet been satisfactory. In addition, in the conventional thermal polymerization method, the temperature is raised to 100℃, which makes the putty-like mixture easy to flow and deforms the fine mucosal structure copied in the oral cavity, making it unsuitable for the direct method. . Recently, the application of photopolymerization to polymerize and solidify dental materials such as filling materials and veneers has become popular, and the use of camphorquinone, a diketone, etc., as a sensitizer has been proposed. (European Patent Publication No. 90493, European Patent Publication No. 59649). However, in this case, reducing agents such as organic peroxides and amines are always used in addition to camphor quinone, and if such peroxides are contained, they are unstable to heat and polymerize and solidify during storage. There was a drawback that it was possible. SUMMARY OF THE INVENTION In view of these facts, the present inventor has made earnest efforts to develop a denture base lining material suitable for the direct method, and as a result, has arrived at the present invention. That is, the present invention is based on the general formula

[Formula] (R ₁ is H or CH ₃ , R ₂ is a fluorine-containing oligomer with a molecular weight of 1500 or less) 100 parts by weight of the monomer (), fluorine-containing copolymer 1 to
This is a denture base lining material made by kneading a mixture of 30 parts by weight and 0.01 to 2 parts by weight of a photosensitizer to form a putty or paste. Since the lining material of the present invention is in the form of a putty or paste, it has fluidity during the operation, and when the lining operation is completed by the direct method, it rapidly polymerizes and solidifies at room temperature by irradiation with light, and has appropriate elasticity (preferably Rigidity modulus 5
-50Kg/ ^cm2 ) and ideal hardness (preferably Shore hardness 25-50 (Type A, 25°C)).

The monomer () represented by the formula can be photopolymerized at an appropriate rate in the presence of a photosensitizer, and is stable against heat because it does not contain organic peroxides. Therefore, it has the advantage that there is no need for special cooling means during the manufacturing process or the distribution process of the product, and there is no fear of polymerization and solidification even if the product is exposed to high temperatures. DETAILED DESCRIPTION OF THE INVENTION The monomer (2) which is one component of the putty-like mixture of the present invention can be produced based on the method described in JP-A-59-117503. That is, for example, by telomerizing a fluorine-containing monomer in an alcohol such as methyl alcohol or ethyl alcohol, a fluorine-containing oligomer having an OH group at the end of the molecular chain can be obtained. The monomer () can be easily obtained by dissolving the oligomer in a solvent such as carbon tetrachloride and carrying out an esterification reaction with acrylic acid chloride or methacrylic acid chloride. The fluorine-containing monomers used in this case include two or more monomers selected from vinylidene fluoride, vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, and hexafluoropropylene. As the fluorine-containing oligomer constituting the ester portion of the monomer (), binary or ternary fluorine-containing oligomers of the above-mentioned fluorine-containing monomers are preferably used. The molecular weight of the fluorine-containing oligomer used is 1,500 or less; if it exceeds 1,500, the molding process is somewhat unsatisfactory. Since the ester component of the monomer () that forms the main component of the putty-like mixture is composed of such multi-element fluorine-containing oligomers, the polymerized and solidified backing material layer has appropriate flexibility and excellent durability. A denture base lined with a mixture of the present invention containing this
No deterioration occurs even after years of use. As the fluorine-containing copolymer which is one of the other components of the putty-like mixture, a copolymer as disclosed in JP-A-55-2919 is used. For example, carbon number 2
-3, preferably selected from vinylidene fluoride, vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, hexafluoropropylene, and its rigidity is 10~150Kg/ ^cm2
It is desirable that A feature of the present invention is the inclusion of a photosensitizer. Due to the presence of a photosensitizer, a lining material with appropriate viscoelasticity can be produced by irradiating the above mixture with light. The fact that monomer () is easily photopolymerized simply in the presence of a photosensitizer alone without the use of organic peroxides as in European Patent Publication No. 90493 is probably due to the polymerizability of monomer (). Compared to other monomers,
This is thought to be because it is extremely high. By not using organic peroxides, this material becomes stable against heat, which is a great advantage in terms of manufacturing and distribution. As the photosensitizer, commonly known photosensitizers such as camphorquinone; fluorenone; benzoin ether: benzophenone; benzyl; 2,2-diethoxyacetophenone; 2,2-dimethoxy-
2-phenylacetophenone; 2-alkylanthraquinone; Michler's ketone, etc. are used.
Among these, camphorquinone and fluorenone are particularly preferred since they can be polymerized with visible light. The weight ratio of each component in the putty-like mixture is 1 part by weight of the fluorine-containing copolymer per 100 parts by weight of the monomer ().
~30 parts by weight, preferably 3 to 20 parts by weight are used. The purpose of this is to impart plasticity to the putty-like or paste-like mixture in order to facilitate the lining operation, and to impart strength to the lining material layer after polymerization and solidification. Therefore, if the amount of the fluorine-containing copolymer is less than 1 part by weight, the viscosity of the putty-like or paste-like mixture will be too low, making the lining operation somewhat inconvenient, and the strength after polymerization will also be low. On the other hand, the amount of fluorine-containing copolymer is 30
If the amount exceeds 1 part by weight, the strength after polymerization will increase, but the viscosity of the putty-like mixture will increase, making the lining operation inconvenient. The amount of photosensitizer used is 0.01 to 2 parts by weight, preferably 0.05 to 1.0 parts by weight. If the amount of photosensitizer is too small, it will take a long time to solidify during light irradiation, which is not practical, and if it is too large, the effect will not change, which will be uneconomical. In addition, in order to adjust the strength and hardness, an appropriate amount of ester such as acrylic ester or methacrylic ester or a crosslinking agent such as triethylene glycol dimethacrylate, or hydrophobic powdered silica (preferably 5 to 20 parts by weight) is added. etc.) can also be added. As a method for producing the paste-like or putty-like mixture of the present invention, a fluorine-containing copolymer and a photosensitizer are added to the monomer (), which is the main component of the mixture, and kneaded.
The kneading is carried out by heating the contents at room temperature or by heating, and it is particularly preferable to heat the contents to 120 to 150°C since this allows for better kneading. By kneading, the paste-like or putty-like mixture has appropriate softness (penetration resistance value 5
~50 g/mm ² ) is extremely easy to operate. In addition, the penetration resistance value was determined by placing 9g of the sample in a compression cell using a Tensilon tester and adjusting the temperature to 20℃.
A stainless steel rod with a diameter of 2.3 m/m is inserted into the sample at a speed of 100 mm/min, and the resistance value at that time is expressed in g/mm ² . The putty-like or paste-like mixture of the present invention is placed in an appropriate amount on the mucosal surface of the denture base, stretched and pressed with fingers, and then inserted into the patient's oral cavity. When irradiated with light outside the oral cavity at room temperature, a denture base whose mucosal surface is lined with a soft fluororesin can be obtained extremely easily in about 5 minutes. The light source used for photopolymerization may be either ultraviolet rays or visible rays, but visible rays are preferred since ultraviolet rays are inconvenient, such as requiring safety goggles and the like. Therefore, it is preferable to use a xenon lamp or a halogen lamp. For example, when a 500W xenon lamp is used, the polymerization reaction is completed in about 5 minutes. Although the photopolymerization may be carried out in air, it is preferable to carry out the photopolymerization in deoxygenated water because it is possible to obtain a uniform lining surface with no variation in polymerization between the surface and the depth of the polymer. As the deoxidized water used for this purpose, it is simplest and most effective to use boiled water or an aqueous solution of an inorganic reducing agent such as Na ₂ SO ₃ . Moreover, glycerin, ethylene glycol, etc. can also be used instead of deoxygenated water. Figure 1 shows the relationship between the irradiation time and the tensile strength of the polymer when visible light (ultraviolet rays are cut) is irradiated from a distance of 90 cm from the sample at room temperature using a 500W xenon lamp, and it takes about 5 minutes. This shows that the polymerization reaction is completed by irradiation of . The sample at this time was 65 x 55 x 1.2 m/m (thickness), and the sample content was the same fluorine-containing monomer used in Example 1.
100 parts by weight, 3 parts by weight of fluorine-containing copolymer, 13 parts by weight of hydrophobic silica, and 0.1 part by weight of camphorquinone. The denture base lining material of the present invention photopolymerized in this way preferably has a hardness of 25 to 50 (Shower hardness
A type, 25°C) surface hardness, and preferably a rigidity of 5 to 50 kg/cm ² , a lining material with appropriate hardness and flexibility that does not deform even when used. , long-term use is possible. This will be explained in more detail with reference to Examples below. (Example 1)

Separately, 100 g of fluorine-containing methacrylic acid ester, in which R ₂ is an oligomer with a molecular weight of 1050 consisting of 50 parts by weight of fluorinylidene, 30 parts by weight of chlorotrifluoroethylene, and 20 parts by weight of tetrafluoroethylene, was obtained. Mix 15 g of a soft fluorine-containing copolymer (vinylidene fluoride/chlorotrifluoroethylene/tetrafluoroethylene = 50/30/20 (weight ratio)) (rigidity 67 Kg/cm ² ) and 0.2 g of camphorquinone, Knead for 10 minutes on a roll at 140°C. When this is cooled to room temperature and vacuum degassed,
A putty-like denture base lining material is obtained. The penetration resistance value (hardness) of this putty-like mixture was 19 g/mm ² . Approximately 1 m/m of the poorly fitting maxillary denture base mucosal surface of a 64-year-old male patient was removed and MMA monomer was applied twice with absorbent cotton (the second application was done after the first application had dried). Then, spread about 10 g of this putty-like mixture on a slightly dry area with your hands and fingers, spreading it as evenly as possible over the mucous membrane surface. Next, this is inserted into the oral cavity and the upper and lower jaws are brought into occlusion. After about 30 seconds, take it out, remove the excess around the edges with a sharp knife, and place it in a 500 c.c. beaker containing 5% Na ₂ SO ₃ 7H ₂ O aqueous solution with the mucous side facing up.
Visible light from a 500W light source from a distance of 90cm 10
Irradiate for minutes. After turning off the light source, it is taken out of the water and washed, the edges are corrected and polished, resulting in a maxillary denture base lined with soft fluororesin. It had good adhesion to mucous membranes and was usable for continued use even after one year. In addition, in order to measure the hardness of the soft resin lined, a test piece (diameter 36 m/m, thickness 7 m/m) was separately polymerized, and the shore hardness (AType) was measured as 32.
(read the value 15 seconds after pressing the hardness meter needle against the sample at 25°C). (Example 2)

In the formula, R ₂ is an oligomer with a molecular weight of 1050 consisting of 50 parts by weight of vinylidene fluoride, 30 parts by weight of chlorotrifluoroethylene, and 20 parts by weight of tetrafluoroethylene. 12 g of soft fluorine-containing copolymer (rigidity 67 Kg/cm ² ) of vinylidene fluoride/chlorotrifluoroethylene/hexafluoropropylene = 50/30/20 (weight ratio), 12 g of hydrophobic silica (AEROSIL R-972) and camphorquinone
Mix 0.1g and knead with a roll at 140℃ for 10 minutes.
This is cooled to room temperature and degassed under vacuum to obtain a putty-like denture base lining material. The penetration resistance value (hardness) of this putty-like mixture was 21 g/mm ² . Next, remove about 1 m/m of the mucosal surface of the mandibular denture that has become poorly fitted, and apply MMA monomer there twice with absorbent cotton (the second application should be done after the first application has dried). Approximately 8g of this putty-like mixture on a dry place
Stretch it with your fingers and spread it as evenly as possible on the mucosal surface. Next, insert it into the mouth of the patient (a 68-year-old man), let him chew gently, and take it out after about 30 seconds.
This was mixed with 500 ml of 5% Na ₂ SO ₃ 7H ₂ O aqueous solution.
Place the tooth in a CC beaker with the mucous side facing up and irradiate it with light (visible light) emitted from a 500W xenon lamp from a distance of 90cm for 10 minutes to obtain a denture base lined with soft fluororesin. In addition, in order to measure the hardness of the lined soft resin, a test piece was made in the same manner as in Example 1, and the shore hardness (AType) was measured.
It was 38.5. This denture base had good adhesion to mucous membranes, and even after 6 months, there was no change and continued use was possible. (Example 3)

In the formula, 100 g of fluorine-containing methacrylic acid ester, in which R ₂ is an oligomer with a molecular weight of 1050 consisting of 50 parts by weight of vinylidene fluoride, 30 parts by weight of chlorotrifluoroethylene, and 20 parts by weight of tetrafluoroethylene, is obtained separately. 12g of soft fluorine-containing copolymer (rigidity 67Kg/cm ² ) of vinylidene fluoride/chlorotrolifluoroethylene/tetrafluoroethylene = 50/30/20 (weight ratio), hydrophobic silica (AEROSIL R-972) 12g and fluorenone 0.1g
Mix and knead on a roll at 140℃ for 10 minutes. This is cooled to room temperature and degassed under vacuum to obtain a putty-like denture base lining material. The penetration resistance value of this putty-like mixture was 23.5 g/mm ² . Next, remove about 1 m/m of the mucosal surface of the poorly fitting mandibular denture and apply MMA monomer there twice with absorbent cotton (the second application should be done after the first application has dried).
Spread about 8 g of this putty-like mixture onto the mucous membrane surface as evenly as possible on a slightly dry area by stretching it with your fingers. Next, insert this into the mouth of the patient (a 70-year-old man), gently bite it, and leave it there for about 30 seconds.
Take it out and put it in a 500 c.c. beaker containing 5% Na ₂ SO ₃ 7H ₂ O aqueous solution with the mucous side facing up.
Light emitted from a 500W xenon lamp (visible light)
When irradiated for 10 minutes from a distance of 90 cm, a denture base lined with soft fluororesin can be obtained. In order to measure the hardness of the lined soft resin, test pieces were prepared in the same manner as in Example 1, and the shore hardness (ATpye) was measured to be 37.0. This denture base has good adhesion to mucous membranes, and even after 6 months,
There was no change and continued use was possible.

[Brief explanation of the drawing]

FIG. 1 shows that the mixture of the present invention is easily polymerized and solidified by light irradiation at room temperature, and the strength reaches its maximum value in about 5 minutes.

Claims (1)

[Claims] 1. General formula (In the formula, R ₁ is H or CH ₃ , R ₂ is two or more selected from vinylidene fluoride, vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, and hexafluoropropylene with a molecular weight of 1500 or less. 100 parts by weight of a monomer (fluorine-containing oligomer consisting of monomers) selected from vinylidene fluoride, vinyl fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, hexafluoropropylene 2
Fluorine-containing copolymers 1 to 30 consisting of more than one type of monomer
A soft denture base lining material prepared by kneading a mixture of parts by weight and 0.01 to 2 parts by weight of a photosensitizer to form a putty or paste. 2. The soft denture base lining material according to claim 1, which uses at least one selected from camphorquinone and fluorenone as a photosensitizer.