A fiber-reinforced polymer denture liner material and a method of making the same

Abstract

This invention provides a fiber-reinforced polymer denture spacer material and its preparation method. Generally, when wearing dentures, it is recommended to use a denture spacer between the denture and the gum line to improve the fit, buffer the pressure during chewing, and enhance the wearer's comfort. The oral environment is an alternating environment of aerobic during the day and anaerobic at night, containing saliva and potentially food debris. Denture spacers operate in this environment, requiring high water absorption and saliva resistance. They also need to withstand the pressure of repeated chewing, demanding high fatigue resistance. This invention fully considers the usage environment and material performance requirements of denture spacers by incorporating fibers into room-temperature curing silicone rubber. The fiber-reinforced polymer denture spacer material provided by this invention has a simple preparation method and possesses advantages such as good elasticity, low edge breakage rate, high tear strength, and good tensile properties, with an elastic recovery rate exceeding 99.6%. In practical applications, the denture spacers produced exhibit excellent performance.

Description

Technical Field

[0001] This invention belongs to the field of medical polymer materials, and relates to a fiber-reinforced polymer denture pad material and its preparation method. Background Technology

[0002] Dentures, commonly known as "false teeth," are similar to how "prosthetic legs" or "prosthetic limbs" are called "prosthetics." "Dentals" refers to teeth that fulfill their "duty" for humans. Medically, it's a general term for restorations made after partial or complete loss of the upper and lower jaw teeth. Complete dentures can maintain a patient's facial aesthetics, speech, and chewing function, relieving the pain of tooth loss. However, dentures also present some problems during wear. First, the contact between the denture and the alveolar bone is often not ideal, frequently causing pain. Second, the gaps between the denture and the gums / maxilla cannot be sealed, allowing food to become trapped between the denture and gums during chewing, causing discomfort and potentially leading to gingivitis and periodontitis. In these cases, denture spacers are used to improve the fit between the denture and the gums, cushioning the pressure during chewing and increasing the wearer's comfort.

[0003] Room temperature cured silicone rubber (RTVPS) is a novel type of organosilicon elastomer that emerged in the 1960s. It is a silicone rubber with hydroxyl (or acetoxy) end groups, a relatively low molecular weight, and is typically a viscous fluid. RTVPS is a semi-inorganic polymer synthetic material with a silicon-oxygen bond backbone and organic side chains. The silicon-oxygen bond structure of the backbone determines its wide operating temperature range (-60 to +250°C). The most significant characteristic of this rubber is that it cures at room temperature without heating or pressure, making it extremely convenient to use.

[0004] An ideal denture spacer should exhibit high elasticity during chewing, followed by viscosity to absorb biting forces and alleviate pain. Dynamic viscoelasticity tests show that room temperature silicone rubber exhibits elastic behavior, thus possessing better cushioning capabilities for chewing pressure, making it an ideal material for denture spacers.

[0005] The oral cavity is an environment that alternates between aerobic during the day and anaerobic at night, containing saliva and potentially food debris. Dental prosthesis spacers operate in this environment, requiring high water absorption and saliva resistance. They also need to withstand the pressure of repeated chewing, demanding high fatigue resistance. Ordinary room-temperature curing silicone prostheses often exhibit excellent initial performance, but over time they become inelastic, crack, and deform. This invention fully considers the characteristics of the prosthesis spacer's usage environment and the material performance requirements. It incorporates fibers into the room-temperature curing silicone rubber, improving its tear strength and elastic recovery rate; reducing the risk of decomposition and breakage of the prosthesis spacer; and improving the comfort and biocompatibility of the prosthesis wearer. Summary of the Invention

[0006] The purpose of this invention is to provide a medical polymer material, and more particularly to provide a fiber-reinforced polymer denture pad material and its preparation method.

[0007] The fiber-reinforced polymer denture pad material of the present invention mainly includes the following components: polysiloxane with hydroxyl-terminated molecular chains, polysiloxane with one or two alkoxysiloxane groups on each molecular chain, siloxane with hydrolyzable groups, chopped fibers, reinforcing materials, nanofillers, consistency modifiers and other additives.

[0008] The amounts of each component, calculated by mass, are as follows: 23–56 parts of polysiloxane with hydroxyl-terminated molecular chains, 36–52 parts of polysiloxane with one or two alkoxysiloxane groups on each molecular chain, 5–25 parts of siloxane containing hydrolyzable groups, 2.8–16 parts of chopped fibers, 5.6–13.5 parts of reinforcing material, 3.5–32 parts of nanofiller, 0–26 parts of consistency modifier, and 0–5 parts of other additives.

[0009] The above-mentioned polysiloxane with hydroxyl-terminated molecular chains has a viscosity of 1000–650000 mPa·s at room temperature, and its structure is shown in structural formula I.

[0010] Structural Formula I

[0011]

[0012] In Formula I, R1 and R2 are alkyl groups containing 1 to 15 carbon atoms, and R3 is a monovalent hydrocarbon group containing 1 to 15 carbon atoms. The value of n needs to be between 50 and 500 depending on the viscosity. The alkyl groups of R1 and R2 include methyl, ethyl, propyl, butyl, pentyl, hexyl, and similar alkyl groups. R3 includes methyl, ethyl, propyl, butyl, pentyl, hexyl, and similar alkyl groups; vinyl, allyl, butenyl, pentenyl, hexenyl, and similar alkenyl groups; and also includes phenyl, tolyl, xylyl, and similar aryl groups.

[0013] The polysiloxanes with one or two alkoxysiloxane groups on each of the above molecular chains have a viscosity of 1000–650000 mPa·s at room temperature, and their structures are shown in structural formula II.

[0014] Structural Form II

[0015]

[0016] In Formula II, R1 is a monovalent hydrocarbon group, either identical or different, that does not contain an aliphatic unsaturated bond, including methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and similar alkyl groups. R2 is an alkyl group, including methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and similar alkyl groups, preferably methyl, ethyl, and propyl. R3 is a monovalent hydrocarbon group, either identical or different, including methyl, ethyl, propyl, butyl, pentyl, hexyl, and similar alkyl groups; vinyl, allyl, butenyl, pentenyl, hexenyl, and similar alkenyl groups; and also includes phenyl, tolyl, xylyl, and similar aryl groups. n0 is an integer from 1 to 100, depending on the need to control viscosity, and n1 is an integer from 0 to 2.

[0017] The aforementioned hydrolyzable siloxanes have two, three, or four silicon-bonded hydrolyzable groups, and their structures are shown in structural formula III.

[0018] Structural Form III

[0019]

[0020] In Formula III, R1 is a monovalent hydrocarbon group having 1 to 10 carbon atoms, including methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and similar alkyl groups. R2 is a hydrolyzable group, and x is 0 or 1. R2 includes methoxy, ethoxy, and similar alkoxy groups; acetoxy, and similar acyloxy groups; N-butylalkyl, and similar alkylamino groups; N-methylacetamide, and similar amide groups; propyleneoxy, and similar alkenoxy groups; N-methylacetamino, and similar amide groups. Among these, preferred are: triacetoxysilane, ethyltriacetylsilane, vinyltriketoxime silane, tetraketoxime silane, triketoxime silane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, or a mixture of one or more.

[0021] The aforementioned chopped fibers include, but are not limited to, glass fibers and carbon nanofibers, with a fiber length between 40 nm and 500 nm.

[0022] The aforementioned reinforcing agents include, but are not limited to, MQ resin, fumed silica, talc, and mica powder, wherein the specific surface area of ​​the fumed silica, talc, and mica powder is 1000 mesh or more.

[0023] The aforementioned nanofillers include, but are not limited to, calcium carbonate, kaolin, and quartz powder, with a specific surface area of ​​1000 mesh or more.

[0024] The aforementioned consistency modifiers include, but are not limited to, dimethyl silicone oil and liquid paraffin.

[0025] The other additives mentioned above include appropriate amounts of fragrances, color pastes, coupling agents, and formulations.

[0026] The fiber-reinforced polymer denture pad material of the present invention may also contain various additives known for use in fiber-reinforced polymer denture pads, within the scope of the present invention without prejudice to its purpose. These additives include, but are not limited to, inorganic fillers, organic solvents, mildew inhibitors, flame retardants, heat stabilizers, plasticizers, and thixotropic agents.

[0027] The method for preparing the fiber-reinforced polymer denture pad material of the present invention is as follows.

[0028] 1) Add polysiloxanes with hydroxyl-terminated molecular chains and polysiloxanes with one or two alkoxysiloxane groups on each molecular chain to a planetary mixer and mix thoroughly. The rotation speed of the planetary mixer is 20–70 rpm.

[0029] 2) Add the chopped fibers to the above mixture and stir for 30 to 70 minutes at a planetary mixer speed of 20 to 70 rpm.

[0030] 3) Add reinforcing materials, nanofillers and other additives, and stir in a planetary mixer at a rotation speed of 20-70 rpm for 30-70 minutes.

[0031] 4) Add siloxane containing hydrolyzable groups, mix well, and add an appropriate amount of consistency adjuster according to the consistency.

[0032] 5) Add the above mixture into a mold with a groove, the mold having a pressing sheet, and press and solidify the pressing sheet to prepare a polymer film of the corresponding thickness. The thickness of the polymer film is 0.3 to 10 mm, preferably: 0.3 mm, 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3.0 mm.

[0033] All technical and scientific terms used in this invention regarding the fiber-reinforced polymer denture spacer material have the same meaning as commonly understood by one of ordinary skill in the art. The fiber-reinforced polymer denture spacer material provided by this invention has a simple preparation method and possesses advantages such as good elasticity, low edge breakage rate, high tear strength, and good tensile properties, with an elastic recovery rate exceeding 99.6%. In practical applications, the denture spacers produced exhibit excellent performance.

[0034] The present invention will be further described below through specific embodiments.

[0035] Example 1

[0036] ① At room temperature, 5600g of polysiloxane with hydroxyl-terminated molecular chains (viscosity 450000mPa·s) and 3600g of polysiloxane with one or two alkoxysiloxane groups per molecular chain (viscosity 20000mPa·s) were added to a planetary mixer and mixed at 50 rpm for 40 minutes. Then, 1500g of chopped glass fibers (65nm in length) were added and the mixture was mixed at 50 rpm for 40 minutes.

[0037] Weigh 500g of calcium carbonate and 500g of fumed silica and add them to the above mixture, stirring at 50 rpm for 60 minutes. Add 2100g of vinyltriketone oxime silane and 400g of 3-methacryloyloxypropyltrimethoxysilane, and stir at 50 rpm for 30 minutes.

[0038] ② Add the above mixture into a grooved mold. The grooved mold has a pressing sheet. Compact and solidify the pressing sheet, controlling the film thickness to 1mm. The elastic recovery rate of this film reaches 99.7%. In practical applications, the polymer film is cut to the corresponding size of the denture pad.

[0039] Example 2

[0040] ① At room temperature, 3350g of polysiloxane with hydroxyl-terminated molecular chains (viscosity 50000mPa·s) and 4600g of polysiloxane with one or two alkoxysiloxane groups per molecular chain (viscosity 650000mPa·s) were added to a planetary mixer and mixed at 55 rpm for 60 minutes. Then, 1350g of chopped glass fibers (85nm in length) were added and the mixture was mixed at 55 rpm for 30 minutes.

[0041] Weigh 6000g of quartz powder, 1000g of MQ resin, and 350g of fumed silica, and mix them together with the above mixture. Stir at 30 rpm for 70 minutes. Add 1100g of vinyltriketone oxime silane and 600g of 3-methacryloyloxypropyltrimethoxysilane, and stir at 45 rpm for 35 minutes.

[0042] ② Add the above mixture into a grooved mold. The grooved mold has a pressing sheet. Compact and solidify the pressing sheet, controlling the film thickness to 1.5mm. The elastic recovery rate of this film reaches 99.8%. In practical applications, the polymer film is cut to the corresponding size of the denture pad.

[0043] Example 3

[0044] ① At room temperature, 2350g of polysiloxane with hydroxyl-terminated molecular chains (viscosity 1000mPa·s) and 5200g of polysiloxane with one or two alkoxysiloxane groups per molecular chain (viscosity 650000mPa·s) were added to a planetary mixer and mixed at 45 rpm for 70 minutes. Then, 2800g of chopped glass fibers (45nm in length) were added and the mixture was mixed at 55 rpm for 35 minutes.

[0045] Weigh 150g of quartz powder, 1400g of calcium carbonate, 1200g of MQ resin, and 210g of fumed silica, and mix them together with the above mixture. Stir at 35 rpm for 70 minutes. Add 400g of ethyltriacetylsilane and 100g of vinyltriketone oxime silane, and stir at 65 rpm for 55 minutes.

[0046] ② Add the above mixture into a grooved mold. The grooved mold has a pressing sheet. Compact and solidify the pressing sheet, controlling the film thickness to 2.0 mm. The elastic recovery rate of this film reaches 99.75%. In practical applications, the polymer film is cut to the corresponding size of the denture pad.

[0047] Example 4

[0048] ① At room temperature, 2300g of polysiloxane with hydroxyl-terminated molecular chains (viscosity 5000mPa·s) and 5000g of polysiloxane with one or two alkoxysiloxane groups per molecular chain (viscosity 600000mPa·s) were added to a planetary mixer and mixed at 45 rpm for 65 minutes. Then, 350g of 150nm long carbon nanofibers were added and the mixture was mixed at 55 rpm for 45 minutes.

[0049] Weigh out 1350g of quartz powder, 1880g of calcium carbonate, 300g of MQ resin, 260g of fumed silica, and 500g of dimethyl silicone oil, and mix them together with the above mixture. Stir at 20 rpm for 70 minutes. Add 750g of ethyltriacetylsilane and 800g of vinyltriketone oxime silane, and stir at 65 rpm for 50 minutes.

[0050] ② Add the above mixture into a grooved mold. The grooved mold has a pressing sheet. Compact and solidify the pressing sheet, controlling the film thickness to 0.3 mm. The elastic recovery rate of this film reaches 99.65%. In practical applications, the polymer film is cut to the corresponding size of the denture pad.

[0051] Example 5

[0052] ① At room temperature, 3650g of polysiloxane with hydroxyl-terminated molecular chains (viscosity 350000mPa·s) and 2500g of polysiloxane with one or two alkoxysiloxane groups per molecular chain (viscosity 300000mPa·s) were added to a planetary mixer and mixed at 40 rpm for 30 minutes. Then, 280g of 500nm long glass fiber was added and the mixture was mixed at 50 rpm for 65 minutes.

[0053] Weigh out 1050g of quartz powder, 1880g of calcium carbonate, 1060g of fumed silica, and 650g of dimethyl silicone oil, and stir them together with the above mixture at 30 rpm for 70 minutes. Add 150g of ethyltriacetylsilane, 400g of vinyltriketoxime silane, and 160g of triketoxime silane, and stir at 65 rpm for 50 minutes.

[0054] ② Add the above mixture into a grooved mold. The grooved mold has a pressing sheet. Compact and solidify the pressing sheet, controlling the film thickness to 3.0 mm. The elastic recovery rate of this film reaches 99.9%. In practical applications, the polymer film is cut to the corresponding size of the denture pad.

[0055] Example 6

[0056] ① At room temperature, 3350g of polysiloxane with hydroxyl-terminated molecular chains (viscosity 300000mPa·s) and 2900g of polysiloxane with one or two alkoxysiloxane groups per molecular chain (viscosity 180000mPa·s) were added to a planetary mixer and mixed at 40 rpm for 35 minutes. Then, 1850g of 100nm long glass fiber was added and the mixture was mixed at 40 rpm for 70 minutes.

[0057] Weigh out 350g of kaolin, 900g of quartz powder, 1230g of calcium carbonate, 960g of fumed silica, and 850g of dimethyl silicone oil, and mix them together with the above mixture. Stir at 45 rpm for 70 minutes. Add 650g of 3-methacryloyloxypropyltriethoxysilane, 200g of vinyltriketoxime silane, and 260g of triketoxime silane, and stir at 65 rpm for 55 minutes.

[0058] ② Add the above mixture into a grooved mold. The grooved mold has a pressure plate. Compact and solidify the pressure plate, controlling the film thickness to 1.5mm. The elastic recovery rate of this film reaches 99.85%. In practical applications, the polymer film is cut to the corresponding size of the denture pad.

Claims

1. A fiber-reinforced polymer denture pad material, characterized in that... The main components include: polysiloxanes with hydroxyl-terminated molecular chains, polysiloxanes with one or two alkoxysiloxane groups on each molecular chain, siloxanes containing hydrolyzable groups, chopped fibers, reinforcing materials, nanofillers, consistency modifiers and other additives. The amounts of each component, calculated by mass, are as follows: 23–56 parts of polysiloxane with hydroxyl-terminated molecular chains, 36–52 parts of polysiloxane with one or two alkoxysiloxane groups on each molecular chain, 5–25 parts of siloxane containing hydrolyzable groups, 2.8–16 parts of chopped fibers, 5.6–13.5 parts of reinforcing material, 3.5–32 parts of nanofiller, 0–26 parts of consistency modifier, and 0–5 parts of other additives; The reinforcing materials are MQ resin, fumed silica, talc, and mica powder, wherein the specific surface area of ​​fumed silica, talc, and mica powder is above 1000 mesh. The nanofiller is calcium carbonate, kaolin, and quartz powder, with a specific surface area of ​​1000 mesh or more; The polysiloxane with hydroxyl-terminated molecular chains has a viscosity of 1000-650000 mPa•s at room temperature, and its structure is shown in structural formula I. Structural Formula I In Formula I, R1 and R2 are alkyl groups containing 1-6 carbon atoms, R3 is a monovalent hydrocarbon group containing 1-6 carbon atoms, and the value of n needs to be between 50 and 500 depending on the viscosity; the alkyl groups of R1 and R2 are selected from methyl, ethyl, propyl, butyl, pentyl, and hexyl; R3 is selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, vinyl, allyl, butenyl, pentenyl, and hexenyl. The polysiloxane, with one or two alkoxysiloxane-containing groups on each molecular chain, has a viscosity of 1000–650000 mPa·s at room temperature, and its structure is shown in structural formula II. Structural Form II In Formula II, R1 is an alkyl group selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl; R2 is an alkyl group selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl; R3 is a monovalent hydrocarbon group, selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, vinyl, allyl, butenyl, pentenyl, and hexenyl; n0 is an integer from 1 to 100 depending on the viscosity control requirements, and n1 is an integer from 0 to 2. The method for preparing the fiber-reinforced polymer denture pad material is as follows: ① Add polysiloxanes with hydroxyl-terminated molecular chains and polysiloxanes with one or two alkoxysiloxane groups on each molecular chain to a planetary mixer and mix them evenly; the rotation speed of the planetary mixer is 20-70 rpm. ② Add the chopped fibers to the above mixture and stir for 30 to 70 minutes at a planetary mixer speed of 20 to 70 rpm; ③ Add reinforcing materials, nanofillers and other additives, and stir for 30 to 70 minutes at a planetary mixer speed of 20 to 70 rpm; ④ Add siloxane containing hydrolyzable groups, mix well, and add an appropriate amount of consistency adjuster according to the consistency. ⑤ Add the above mixture into a mold with a groove. The mold has a pressing sheet. Press the pressing sheet to solidify and prepare a polymer film of the corresponding thickness, which is 0.3 to 10 mm.

2. The fiber-reinforced polymer denture pad material as described in claim 1, characterized in that... Siloxanes containing hydrolyzable groups have two, three, or four silicon-bonded hydrolyzable groups, and their structures are shown in structural formula III. Structural Form III In Formula III, R1 is a monovalent hydrocarbon group having 1-7 carbon atoms, selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl; R2 is a hydrolyzable group, and the value of x is 0 or 1; R2 is selected from methoxy, ethoxy, acetoxy, N-butylalkyl, N-methylacetamide, propenoxy, and N-methylacetamido groups.

3. The fiber-reinforced polymer denture pad material as described in claim 2, characterized in that... The siloxane containing a hydrolyzable group is selected from triacetoxysilane, ethyltriacetylsilane, vinyltriketoxime silane, tetraketoxime silane, triketoxime silane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, or a mixture of one or more thereof.

4. The fiber-reinforced polymer denture pad material as described in claim 1, characterized in that... The chopped fibers are selected from glass fibers and carbon nanofibers, with a fiber length between 40 nm and 500 nm.

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