Dental composite resin containing dumbbell-shaped fluorapatite filler and preparation method thereof
阅读说明：本技术 一种含哑铃状氟磷灰石填料的齿科复合树脂及其制备方法 (Dental composite resin containing dumbbell-shaped fluorapatite filler and preparation method thereof ) 是由 张青红 李楠 王宏志 李耀刚 侯成义 朱美芳 于 2020-12-31 设计创作，主要内容包括：本发明涉及一种含哑铃状氟磷灰石填料的齿科复合树脂及其制备方法,原料组分包括：有机树脂基材、SiO-2微球,纳米棒构筑的哑铃状氟磷灰石。本发明制备工艺简单,条件温和,适合于工业批量生产,在齿科修复复合材料领域具有广阔的应用前景。(The invention relates to a dental composite resin containing dumbbell-shaped fluorapatite filler and a preparation method thereof, and the dental composite resin comprises the following raw material components: organic resin base material and SiO 2 The dumbbell-shaped fluorapatite is constructed by the microspheres and the nanorods. The invention has simple preparation process and mild conditions, is suitable for industrial batch production, and has wide application prospect in the field of dental repair composite materials.)
1. The dental composite resin is characterized by comprising the following raw material components in percentage by mass:
20 to 30 percent of organic resin matrix and initiator,
SiO210 to 70 percent of microsphere,
10-70% of dumbbell-shaped fluorapatite constructed by the modified nano-rods.
2. The composite resin according to claim 1, wherein the organic resin matrix is bisphenol a-glycidyl methacrylate Bis-GMA, triethylene glycol dimethacrylate TEGDMA; the initiator is ethyl p-dimethylaminobenzoate 4-EDMAB and camphorquinone CQ, wherein the mass ratio of Bis-GMA, TEGDMA, 4-EDMAB and CQ is 49.5 (40-50) to 0.5-1 to 0.1-1; the SiO2The microspheres are modified SiO2The particle size of the microspheres is 400-450 nm.
3. The composite resin according to claim 2, wherein the modified SiO is2The microspheres are prepared by the following method:
cyclohexane, SiO2Uniformly mixing the microspheres, the gamma-MPS and the n-propylamine at room temperature, then heating to react, centrifugally washing and drying to obtain the modified SiO2And (3) microspheres.
4. The composite resin of claim 1, wherein the modified nanorod-constructed dumbbell-shaped fluorapatite is prepared by the following method:
adding disodium ethylenediamine tetraacetic acid Na2EDTA, citric acid CA, calcium nitrate Ca (NO)3)2Diammonium hydrogen phosphate (NH)4)2HPO4Adding into deionized water, adjusting pH, adding sodium fluoride NaF for hydrothermal reaction, centrifuging, washing, and oven drying to obtain dumbbell-shaped fluorapatite constructed by nanorods with specific surface area higher than 50m2/g；
And magnetically stirring cyclohexane, the dumbbell fluorapatite, the gamma-MPS and the n-propylamine at room temperature at a high speed until the materials are uniformly mixed, then raising the temperature for reaction, centrifugally washing and drying to obtain the modified nanorod-constructed dumbbell fluorapatite.
5. The resin composite according to claim 4, wherein the disodium salt of ethylenediaminetetraacetic acid Na is2EDTA, citric acid CA, calcium nitrate Ca (NO)3)2Diammonium hydrogen phosphate (NH)4)2HPO4And the concentration of the aqueous solution of sodium fluoride NaF is 12-13 g/L, 20-22 g/L, 10-15 g/L, 1-5 g/L and 0.1-0.2 g/L respectively; the pH range of the solution is 4-6; the hydrothermal reaction process condition is that the hydrothermal reaction is carried out for 8-10 h at the temperature of 120-150 ℃.
6. The composite resin as claimed in claim 4, wherein the concentrations of cyclohexane, γ -MPS and n-propylamine are 700-800 g/L, 10-20 g/L and 3-5 g/L respectively; the temperature of the heating reaction is 60-65 ℃, and the reaction time is 0.5-1 h.
7. A method for preparing dental composite resin, comprising:
weighing the raw materials according to claim 1, and modifying the SiO2The microspheres, the dumbbell-shaped fluorapatite and the organic resin matrix are uniformly mixed and are subjected to photocuring forming, and the silicon-based dental composite resin is obtained.
8. The preparation method of claim 7, wherein the light curing molding is performed by using 480nm LED blue light as a light source.
Technical Field
The invention belongs to the field of dental composite resin and preparation thereof, and particularly relates to dental composite resin containing dumbbell-shaped fluorapatite filler and a preparation method thereof.
Background
The dental restorative composite resin is generally prepared from an organic matrix, an initiator, and an inorganic filler (such as SiO)2Glass powder, SiC whisker, inorganic fiber, etc.). Among the most widely used organic substrates are the monomeric bisphenol a-glycidyl methacrylate (Bis-GMA) and the diluent triethylene glycol dimethacrylate (TEGDMA) system. Because of the advantages of aesthetic property, convenient clinical operation and cost, the composite resin is the most popular dental repair material at present.
Through continuous research and development, all components and curing modes of the composite resin are greatly improved, but the defects of low mechanical property, high polymerization shrinkage rate and the like are still required to be overcome. It is these shortcomings that the service life of the silver-mercury alloy is only 30% -40% of that of the silver-mercury alloy, so that the improvement of the mechanical property is necessary. The influence of the type and structure of the inorganic filler on the mechanical property of the composite resin is the most remarkable. #
The main inorganic component of human enamel and dentin is hydroxyapatite (HAp), but contains some degree of fluoride ions, in the form of fluorapatite or fluorocarbon hydroxyapatite. This is because fluorine ions are the most electronegative elements and are liable to substitute OH-、Cl-、CO3 2-Other ions to achieve higher symmetry, so that fluorapatite has better chemical stability (more difficult to dissolve in a body fluid environment) than hydroxyapatite. Meanwhile, the fluorapatite can release F under a lower pH environment-Thereby having the functions of antibiosis and caries prevention to a certain extent. At present, the fluorapatite with the shapes of particle, whisker and the like is applied to dental repair resin, but the one-dimensional fillers have relatively smooth surfaces and relatively small specific surface areas, so the reinforcing effect is not obvious (Taheri M.M., et al, Materials)&Design,2015,82, 119-125). Therefore, it is necessary to search a fluorapatite with a three-dimensional bionic structure for improving the mechanical property of dental repair resin.
Disclosure of Invention
The invention aims to solve the technical problem of providing dental composite resin containing dumbbell-shaped fluorapatite filler and a preparation method thereof, and overcoming the technical curve of poor reinforcing effect in the prior art.
The dental composite resin is characterized by comprising the following raw material components in percentage by mass:
20 to 30 percent of organic resin matrix and initiator,
SiO210 to 70 percent of microsphere,
10-70% of dumbbell-shaped fluorapatite constructed by the modified nano-rods.
The organic resin matrix is bisphenol A-glycidyl methacrylate Bis-GMA and triethylene glycol dimethacrylate TEGDMA; the initiator is ethyl p-dimethylaminobenzoate 4-EDMAB and camphorquinone CQ; wherein the mass ratio of Bis-GMA, TEGDMA, 4-EDMAB and CQ is 49.5 (40-50) to 0.5-1 to 0.1-1; the SiO2The microspheres are modified SiO2The particle size of the microspheres is 400-450 nm.
The modified SiO2The microspheres are prepared by the following method:
cyclohexane, SiO2Magnetically stirring the microspheres, the gamma-MPS and the n-propylamine at room temperature at a high speed for 30-40min, uniformly mixing, heating for reaction, centrifugally washing and drying to obtain modified SiO2Microspheres; wherein, SiO2The mass range of the microspheres is 5-10 g, and the concentrations of cyclohexane, gamma-MPS and n-propylamine are 700-800 g/L, 10-20 g/L and 3-5 g/L respectively.
The dumbbell-shaped fluorapatite constructed by the modified nano-rods is prepared by the following method:
adding disodium ethylenediamine tetraacetic acid Na2EDTA, citric acid CA, calcium nitrate Ca (NO)3)2Diammonium hydrogen phosphate (NH)4)2HPO4Adding the mixture into deionized water, adjusting the pH value, adding sodium fluoride NaF to perform hydrothermal reaction, centrifugally washing and drying to obtain dumbbell-shaped fluorapatite; wherein the centrifugal washing comprises the following steps: is removed fromRespectively centrifugally washing the seed water and absolute ethyl alcohol for 3-4 times; the drying specifically comprises the following steps: firstly, drying in a common oven until no obvious moisture exists, and then drying in a vacuum oven at the temperature of 60-80 ℃ for 10-24 hours;
magnetically stirring cyclohexane, dumbbell fluorapatite, gamma-MPS and n-propylamine at room temperature for 30-40min at a high speed until the materials are uniformly mixed, then raising the temperature for reaction, centrifugally washing and drying to obtain the modified nanorod-constructed dumbbell fluorapatite; wherein the weight range of the dumbbell-shaped fluorapatite is 5-10 g, and the concentrations of the cyclohexane, the gamma-MPS and the n-propylamine are 700-800 g/L, 10-20 g/L and 3-5 g/L respectively. Wherein the centrifugal washing comprises the following steps: respectively centrifugally washing the mixture for 3-4 times by using deionized water and absolute ethyl alcohol; the drying specifically comprises the following steps: drying in a common oven until no obvious moisture exists, and drying in a vacuum oven at 60-80 ℃ for 10-24 h.
The disodium salt of ethylene diamine tetraacetic acid Na2EDTA, citric acid CA, calcium nitrate Ca (NO)3)2Diammonium hydrogen phosphate (NH)4)2HPO4And the concentration of the aqueous solution of sodium fluoride NaF is 12-13 g/L, 20-22 g/L, 10-15 g/L, 1-5 g/L and 0.1-0.2 g/L respectively; the pH range of the solution is 4-6; the hydrothermal reaction process condition is that the hydrothermal reaction is carried out for 8-10 h at the temperature of 120-150 ℃.
The concentrations of the cyclohexane, the gamma-MPS and the n-propylamine are respectively 700-800 g/L, 10-20 g/L and 3-5 g/L; the temperature of the heating reaction is 60-65 ℃, and the reaction time is 0.5-1 h.
The invention discloses a preparation method of dental composite resin, which comprises the following steps:
weighing the raw materials, and modifying the modified SiO2The microspheres, the dumbbell-shaped fluorapatite and the organic resin matrix are uniformly mixed and are subjected to photocuring forming, and the silicon-based dental composite resin is obtained.
The light curing molding is performed by adopting 480nm LED blue light as a light source.
The invention also discloses application of the dental composite resin.
The invention synthesizes dumbbell fluorapatite by a hydrothermal method; gamma-methyl propylene acyloxy propyl trimethoxy silane (gamma-MPS) is used as modifierModified dumbbell fluorapatite; mixing organic resin matrix, dumbbell-shaped fluorapatite and SiO2The microspheres and the photoinitiator are mixed into uniform pasty slurry according to a certain proportion, and the paste is filled into a mould and is subjected to photocuring to obtain the composite resin.
The invention adopts modified dumbbell-shaped fluorapatite as a part of inorganic filler, and SiO is compounded according to a certain proportion2Adding the microspheres into an organic resin matrix, and carrying out photocuring to obtain the dental composite resin. The dumbbell-shaped fluorapatite has larger specific surface area, antibacterial property and good biocompatibility, and is in contact with SiO2The mechanical property of the dental composite resin is enhanced after the microspheres are mixed.
In the invention, the structure of the dumbbell-shaped fluorapatite is very similar to the inorganic components (hydroxyapatite, fluorapatite and other crystals) orderly arranged in the enamel, and the specific surface area of the dumbbell-shaped fluorapatite is 76.4m by BET specific surface area measurement2The specific surface area is large and the agglomeration is not easy to occur. It is mixed with SiO2The microspheres jointly used as the inorganic filler can be uniformly dispersed and tightly filled in the organic resin matrix, so that the mechanical property of the composite resin is effectively improved. The composite resin has good mechanical property, and the bending strength of the composite resin is far higher than the international standard strength value (80MPa) of a dental repair material used for an occlusion area.
Advantageous effects
(1) The invention has simple experimental method, easy preparation and wide application prospect in the field of dental repair composite materials;
(2) in the invention, SiO is used as the raw material2The dental composite resin prepared from the microspheres and the dumbbell-shaped fluorapatite has higher mechanical property which is shown in comparison with single SiO2The compression strength, the bending strength and the bending modulus of the composite resin are improved by 10 percent or more by virtue of the filler of the microspheres;
(3) the dumbbell-shaped fluorapatite prepared by the method has the characteristics of large specific surface area and ordered arrangement structure similar to tooth enamel, has higher enhancement effect on the mechanical property of the silicon-based composite resin, and has certain antibacterial property.
Drawings
FIG. 1 is a flow chart of the preparation of the dental composite resin reinforced by the dumbbell-shaped fluorapatite filler according to the present invention;
FIG. 2 is a scanning electron micrograph of dumbbell-shaped fluorapatite prepared in example 1 according to the present invention; wherein, the picture (A) is a scanning electron micrograph of the dumbbell-shaped fluorapatite with the magnification of 9K; FIG. B is a scanning electron micrograph of dumbbell-shaped fluorapatite at a magnification of 30K.
FIG. 3 is a scanning electron micrograph of a cross-section of the composite resin prepared in example 1; wherein, the picture (A) is a scanning electron micrograph of the composite resin at a magnification of 5K; FIG. B is a scanning electron micrograph of the composite resin at a magnification of 25K.
Fig. 4 is a digital photograph showing the antibacterial performance of the composite resins prepared in example 1 and comparative example 1.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
(1) Flexural Strength and flexural modulus
The prepared composite resin is filled into a silica gel mold with the size of 25mm multiplied by 2mm by a stainless steel scraper, and after the surface is flattened by a glass sheet, the upper surface and the lower surface are respectively cured for 60s by using a blue light photocuring lamp. The specimens were removed and 6 samples were prepared for each set. The prepared specimens were left at dry room temperature for 2 to 3 days, and the surface was sanded with abrasive paper before testing. The flexural strength and flexural modulus were measured and the values recorded.
(2) Compressive strength
The prepared composite resin is filled into a silica gel mold with phi 4mm multiplied by 6mm by a stainless steel scraper, the surface is flattened by a glass sheet, and the upper surface and the lower surface are respectively cured for 60s by a blue light photocuring lamp. The specimens were removed and 6 samples were prepared for each set. The prepared specimens were left at dry room temperature for 2 to 3 days, and the surface was sanded with abrasive paper before testing. The compression strength test was performed and the values were recorded.
(3) Antibacterial property
The prepared composite resin is filled into a cylindrical silica gel mold with the diameter of phi 20mm multiplied by 1mm by a stainless steel scraper, and the upper surface is flattened by a glass sheet. The upper and lower surfaces were cured for 60 seconds using a blue light curing lamp. The samples were removed and 6 samples were prepared per group. And placing the prepared sample strip at a drying room temperature for 2-3 days, and polishing the surface by using sand paper before testing. Samples of the resin were tested for antibacterial activity (Streptococcus mutans) according to standard procedures of ASTM E2180-07(2017) and cellular activity was calculated according to the following formula: r% ((a-b) × 100)/a. Wherein R represents cell activity, a and b represent the number of colonies left by the elution operation after the blank group and the experimental group are cultured for 24h respectively.
Raw material source and specification parameters
Note: modified SiO used in example 2 and comparative examples 1 to 22The specific preparation of microspheres and modified dumbbell fluorapatite were the same as in example 1.
Example 1
(1) 0.93g of EDTA-2 Na and 1.68g of CA-H were weighed2O，1.18g Ca(NO3)2·4H2O and 0.4g (NH)4)2HPO4Then the mixture is added into 80mL deionized water preheated by a water bath (40 ℃) and stirred evenly, then the pH of the mixed solution is adjusted to 5.2 by using a sodium hydroxide aqueous solution and a nitric acid aqueous solution, 0.01g NaF is added, the mixture is stirred for 20min and then transferred into a 100mL reaction kettle, and the hydrothermal reaction is carried out for 8h at 150 ℃. And (3) respectively centrifugally washing precipitates obtained by the reaction with deionized water and absolute ethyl alcohol for 4 times, and drying in a vacuum oven at the temperature of 80 ℃ for 12 hours.
(2) Weighing 10g of SiO2Mixing and stirring the microspheres, 1.1mL of gamma-MPS, 200mL of cyclohexane and 0.51mL of n-propylamine for 30min at room temperature; then the temperature is increased to 60 ℃ and the reaction is stirred for 30 min. And respectively centrifugally washing the deionized water and the cyclohexane for 4 times, and drying the washed solution in a vacuum oven at the temperature of 80 ℃ for 12 hours. Modified S can be obtainediO2And (3) microsphere powder.
(3) Weighing 10g of dumbbell fluorapatite, 1.1mL of gamma-MPS, 200mL of cyclohexane and 0.51mL of n-propylamine, mixing and stirring for 30min at room temperature; then the temperature is increased to 60 ℃ and the reaction is stirred for 30 min. Respectively centrifugally washing the mixture for 4 times by using deionized water and cyclohexane; drying in a common oven until no obvious moisture exists, and drying in a vacuum oven at 60-80 ℃ for 12 h. Thus obtaining the modified dumbbell-shaped fluorapatite.
(4) 3g of modified SiO2The microspheres, 0.5g of modified dumbbell fluorapatite, 1.5g of organic resin matrix (wherein Bis-GMA: TEGDMA:4-EDMAB: CQ ═ 49.5:49.5:0.8:1) were premixed by a double-center mixing disperser, and then the resin was further mixed by a three-roll mill, and finally the composite resin was prepared by photocuring.
According to the test evaluation method, samples with different sizes and patterns are prepared respectively, and then the mechanical property test (bending strength, bending modulus, compression strength) and the antibacterial property test are carried out, and the test results are shown in table 1.
As shown in FIG. 2, the hydrothermal preparation of dumbbell-shaped fluorapatite has a size of about 2 μm in length and a dumbbell-shaped junction length of about 500 nm. The structure of the enamel is very similar to that of inorganic substances (hydroxyapatite, fluorapatite and other crystals) which are orderly arranged in the enamel, and the enamel has the characteristics of large specific surface area and difficult agglomeration.
As shown in figure 3, the compatibility of the dumbbell-shaped fluorapatite and the organic resin matrix is good, and the cross section of the composite resin has obvious steps, which shows that 10 wt% of the dumbbell-shaped fluorapatite has a great enhancing effect after being added.
As shown in FIG. 4, the composite resin is endowed with antibacterial performance by proper filling amount, which indicates that the resin prepared by the invention is expected to be applied to the field of dental clinical repair materials.
Example 2
2.5g of modified SiO2Premixing microspheres, 1g of modified dumbbell fluorapatite, 1.5g of organic resin matrix (wherein Bis-GMA: TEGDMA:4-EDMAB: CQ: 49.5:0.8:1) by using a double-center mixing disperser, further mixing the resin by using a three-roll grinder, and finally carrying out photocuring to obtain the modified dumbbell fluorapatite/organic resin composite materialAnd (3) compounding the resin.
According to the test evaluation method, samples with different sizes and patterns are prepared respectively, and then the mechanical property test (bending strength, bending modulus, compression strength) and the antibacterial property test are carried out, and the test results are shown in table 1. The other steps are the same as in example 1.
From Table 1, it can be seen that when dumbbell-shaped fluorapatite is substituted for SiO2When the amount of (B) is increased to 20 wt%, the mechanical properties are deteriorated. The proper filling ratio is shown to endow the composite resin with higher mechanical properties.
Comparative example 1
3.5g of modified SiO2The microspheres and 1.5g of organic resin matrix (wherein Bis-GMA: TEGDMA:4-EDMAB: CQ ═ 49.5:49.5:0.8:1) were premixed by a double-center mixing disperser, the resin was further mixed by a three-roll mill, and finally photocured to give a composite resin.
According to the test evaluation method, samples with different sizes and patterns are prepared respectively, and then the mechanical property test (bending strength, bending modulus, compression strength) and the antibacterial property test are carried out, and the test results are shown in table 1. The other steps are the same as in example 1.
As can be seen from Table 1, when 70 wt% SiO was simply filled2In the case of microspheres (i.e., comparative example 1), the properties were lower than those of the resin of a component mixed filler, indicating that when the filling ratio was appropriate, SiO was used2The mechanical properties of the composite resin are better when the microspheres are used with dumbbell fluorapatite (i.e. example 1).
Comparative example 2
3.5g of modified dumbbell fluorapatite and 1.5g of organic resin matrix (wherein Bis-GMA: TEGDMA:4-EDMAB: CQ: 49.5:0.8:1) are premixed by a double-center mixing disperser, then a three-roll grinder is used for further mixing the resin, and finally the composite resin is prepared by photocuring.
According to the test evaluation method, samples with different sizes and patterns are prepared respectively, and then the mechanical property test (bending strength, bending modulus, compression strength) and the antibacterial property test are carried out, and the test results are shown in table 1. The other steps are the same as in example 1.
From Table 1, it can be seen that when the loading was 70 wt% dumbbellThe performance of the fluorapatite-like material is lower than that of the resin mixed with the filler, indicating that SiO is singly filled2The resin performance is poor when the microspheres or dumbbell-shaped fluorapatite are used. When two different fillers are added and the filling proportion is proper, the mechanical property of the composite resin is better.
Table 1 shows the component contents, mechanical properties (compressive strength, flexural strength) and antibacterial properties of examples 1 to 2 and comparative examples 1 to 2.
Mixing SiO2The total filling amount of the microspheres and the dumbbell-shaped fluorapatite is controlled to be 70 wt%. Comparative examples were each a single 70 wt% SiO charge2Microspheres (comparative example 1) and dumb-bell fluorapatite (comparative example 2) simply filled with 70 wt%. As can be seen from Table 1, when SiO2When the compound resin is partially substituted by the dumbbell-shaped fluorapatite (namely, the examples 1 and 2), the mechanical property of the compound resin is greatly improved compared with that of a comparative example. When the substitution amount is 10 wt%, the mechanical property is optimal, and the compressive strength reaches 357 MPa. However, the composite resin of the formula contains less fluorapatite, and the antibacterial property is weaker. When the content of the dumbbell-shaped fluorapatite is increased to 70 wt%, the antibacterial property of the composite resin can reach more than 99.9%. Bis-GMA \ TEGDMA-based composite resin prepared by Taheri et al and using fluorapatite nano-rods (with hexagonal cross-section) as filling material has the fluorapatite filling amount of 0.2 wt% when the mechanical property is best, the bending strength of about 100MPa, and the bending modulus of about 2.5GPa (M.M.Taheri, et al. fluorinated hydrophilic nanoparticles for improving mechanical properties of composite resin: Synthesis and application, Materials&Design,2015,82,119-125)
The dumbbell-shaped fluorapatite prepared by the method has the characteristics of large specific surface area and ordered arrangement structure similar to tooth enamel, has higher enhancement effect on the mechanical property of the silicon-based composite resin, and has certain antibacterial property. This patent uses silica and dumbbell shape fluorapatite as combined raw materials, and the contrast is difficult to obtain: compareIn a single SiO2The compression strength, the bending strength and the bending modulus of the composite resin are improved by 10 percent or more by virtue of the filler of the microspheres; compared with a single rod-shaped fluorapatite structure, the composite filling material effectively improves the space utilization rate in the resin, greatly improves the bending strength and modulus, and has unexpected technical effects.