Photocuring veneering resin cement with high color stability

Abstract

The invention belongs to the technical field of biomedical materials, and particularly relates to high-color-stability photocuring veneering resin cement which comprises the following components in percentage by weight: 20%-40% of acrylate monomers, 0.03%-0.3% of a photosensitizer, 0.03%-0.3% of a photoinitiator, 0.03%-0.3% of an inhibitor and 60%-80% of filler, wherein the photoinitiator is tertiary amine with an electron withdrawing group; according to the light-cured veneering resin cement with high color stability, the electron density of nitrogen atoms is reduced through a conjugation effect by using a tertiary amine initiator containing an electron withdrawing group, so that the occurrence of an oxidation side reaction is inhibited; meanwhile, after tertiary amine is oxidized to generate nitrogen free radical cations, an electron withdrawing group can still stabilize the intermediate and prevent the intermediate from being further decomposed into colored products, so that the color stability of veneering resin cement is continuously kept at a relatively high level in veneering repair, and teeth are kept attractive.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of biomedical materials, and particularly relates to a light-cured veneer resin cement with high color stability. BACKGROUND

[0002] Dental veneer restoration is an important dental aesthetic restoration. After a small amount of tooth surface is ground, a veneer prosthesis (usually a full porcelain tooth) is bonded to the tooth surface using bonding technology. It can improve the appearance of teeth, such as shape, size and color; narrow the tooth gap; cover the discolored teeth; and restore the strength of the teeth.

[0003] When performing veneer restoration, the bonding material used by dentists is usually a light-cured veneer resin cement. These resin cements may discolor over time due to the influence of light, oxidation, hydrolysis, etc., lose color stability, and affect the aesthetics of veneer restoration.

[0004] The main reason for the discoloration of the resin cement is the oxidation discoloration and fading of the light-cured component. Therefore, how to overcome the poor color stability of the light-cured component after aging is a technical problem that needs to be solved in the art.

[0005] It should be noted that the above information disclosed in the background section is only used to understand the background of the present application, and therefore, the above description is not considered to constitute prior art information. SUMMARY

[0006] The present disclosure provides at least a light-cured veneer resin cement with high color stability.

[0007] In a first aspect, the present disclosure provides a light-cured veneer resin cement with high color stability, comprising the following components in percentage by weight: 20-40% of an acrylate monomer, 0.03-0.3% of a photosensitizer, 0.03-0.3% of a photoinitiator, 0.03-0.3% of an inhibitor, and 60-80% of a filler; wherein the photoinitiator is a tertiary amine with an electron-withdrawing group.

[0008] In an optional embodiment, the structure of the photoinitiator is:

[0009] ; wherein R is an electron-withdrawing group.

[0010] In an optional embodiment, the R includes any one of CN, COOH, COOCH3, COOCH2CH3, and COOCH2CH2CH3.

[0011] In an optional embodiment, the photoinitiator includes any one or more combinations of 4-dimethylaminobenzoic acid, ethyl 4-dimethylaminobenzoate, and 4-(dimethylamino)benzonitrile.

[0012] In an optional embodiment, the acrylic acid ester monomer is selected from one or more combinations of acrylic resin monomers containing monofunctional groups, difunctional groups and multifunctional groups; wherein the monofunctional group includes hydroxyethyl methacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, hydroxyethyl acrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, propylene glycol ... The difunctional group includes dimethacrylate urethane, bisphenol A glycidyl dimethacrylate, triethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, 1,8-octanediol diacrylate, 1,10-decanediol diacrylate, 1,12-dodecanediol dimethacrylate; the multifunctional group includes trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and dipentaerythritol pentaacrylate.

[0013] In an alternative embodiment, the photosensitizer comprises camphorquinone.

[0014] In an alternative embodiment, the inhibitor comprises di-tert-butyl-p-cresol.

[0015] In an optional embodiment, the filler comprises an inert glass powder filler.

[0016] In an optional embodiment, the molar ratio of the photosensitizer to the initiator is 1:1 to 1:2; the molar ratio of the inhibitor to the initiator is 1:1 to 1:5.

[0017] The beneficial effect of the present invention is that the light-curing veneer resin cement with high color stability uses a tertiary amine initiator containing an electron-withdrawing group to reduce the electron density of the nitrogen atom through the conjugation effect, thereby inhibiting the occurrence of oxidative side reactions. At the same time, after the tertiary amine is oxidized to generate a nitrogen free radical cation, the electron-withdrawing group can still stabilize the intermediate to prevent it from further decomposing into a colored product, thereby maintaining the color stability of the veneer resin cement at a high level during veneer restoration and maintaining the beauty of the teeth.

[0018] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description.

[0019] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail as follows. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0021] As used herein, the phrases "in one embodiment," "according to one embodiment," "in some embodiments," and the like generally refer to the fact that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure. Thus, a particular feature, structure, or characteristic may be included in more than one embodiment of the present disclosure, such that these phrases do not necessarily refer to the same embodiment. As used herein, the terms "example," "exemplary," and the like are used to "serve as an example, instance, or illustration." Any implementation, aspect, or design described herein as "example" or "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations, aspects, or designs. Instead, the use of the terms "example," "exemplary," and the like is intended to present concepts in a concrete manner.

[0022] As used herein, expressions such as “at least one of,” when following a list of elements, modify the entire list of elements and do not modify the individual elements of the list. For example, the expression “at least one of a, b, and c” should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.

[0023] The terms used herein are only used to describe specific exemplary configurations and are not intended to be limiting. As used herein, the singular articles "a", "an" and "the" may also be intended to include plural forms, unless otherwise clearly indicated herein. The terms "comprise", "include" and "have" are inclusive and therefore specify the presence of features, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components and / or combinations thereof. The method steps, processes and operations described herein should not be interpreted as necessarily requiring them to be performed in the particular order discussed or shown, unless specifically identified as an execution order. Additional or alternative steps may be adopted.

[0024] The following are some embodiments of the present invention described in detail. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0025] The embodiment of the present disclosure provides a light-cured veneer resin cement with high color stability, which includes the following components in weight percentage: 20% to 40% of acrylate monomer, 0.03% to 0.3% of photosensitizer, 0.03% to 0.3% of photoinitiator, 0.03% to 0.3% of inhibitor, and 60% to 80% of filler; wherein the photoinitiator is a tertiary amine having an electron-withdrawing group.

[0026] In some embodiments, specifically, the photoinitiator has the structural formula:

[0027] ; Wherein, R is an electron-withdrawing group.

[0028] In some embodiments, specifically, R includes any one of CN, COOH, COOCH3, COOCH2CH3, and COOCH2CH2CH3.

[0029] In some embodiments, specifically, the photoinitiator includes any one or more combinations of 4-dimethylaminobenzoic acid, ethyl 4-dimethylaminobenzoate, and 4-(dimethylamino)benzonitrile.

[0030] In some embodiments, specifically, the acrylic acid ester monomer is selected from one or more combinations of acrylic acid resin monomers containing monofunctional groups, difunctional groups and multifunctional groups; wherein the monofunctional group includes hydroxyethyl methacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, hydroxyethyl acrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, propylene glycol ... The difunctional group includes dimethacrylate urethane, bisphenol A glycidyl dimethacrylate, triethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, 1,8-octanediol diacrylate, 1,10-decanediol diacrylate, 1,12-dodecanediol dimethacrylate; the multifunctional group includes trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and dipentaerythritol pentaacrylate.

[0031] In some embodiments, specifically, the photosensitizer comprises camphorquinone.

[0032] In some embodiments, specifically, the inhibitor includes di-tert-butyl-p-cresol.

[0033] In some embodiments, specifically, the filler includes an inert glass powder filler.

[0034] In some embodiments, specifically, the molar ratio of the photosensitizer to the initiator is 1:1 to 1:2; the molar ratio of the inhibitor to the initiator is 1:1 to 1:5.

[0035] The present invention is further described below by listing examples and comparative examples, but the present invention is not limited to the following examples. Examples 1-2 are light-cured veneer resin cements of the present invention, and Comparative Examples 1-4 are comparative experimental groups; the formulations of Examples 1-2 and Comparative Examples 1-4 are shown in Table 1.

[0036] Table 1 Formulations of Examples and Comparative Examples (wt%)

[0037]

[0038]

[0039] Specifically, the abbreviations in the table correspond to each other as follows: UDMA: urethane dimethacrylate; BisGMA: bisphenol A glycidyl dimethacrylate; TEGDMA: triethylene glycol dimethacrylate; DDDMA: 1,12-dodecanediol dimethacrylate; CQ: camphorquinone (molecular weight 166 g / mol); EDMAB: ethyl 4-dimethylaminobenzoate (molecular weight 193 g / mol); DMABN: 4-(dimethylamino)benzonitrile (molecular weight 146 g / mol); DHETD: dihydroxyethyl-p-methylaniline (molecular weight 195 g / mol); BHT: di-tert-butyl-p-cresol (molecular weight 220 g / mol); MEHQ: 4-methoxyphenol (molecular weight 124 g / mol).

[0040] Test results

[0041] The color stability test of the embodiment and the comparative example was performed. The test results are shown in Table 2.

[0042] Table 2: Test results of Examples 1-2 and Comparative Examples 1-4

[0043]

[0044]

[0045] Color stability test steps:

[0046] Samples from the Examples and Comparative Examples were prepared as 1 mm thick, 10 mm diameter discs, and then fully light-cured on both sides. The cured discs were tested for color using a colorimeter. The discs were then placed in 55°C water for 15 weeks (equivalent to one year's oral temperature) for accelerated aging. The discs were then air-dried and their color values ​​measured again. The color difference, ΔE, was calculated. A ΔE of less than 2 indicates that the color difference is indistinguishable to the average eye, while a ΔE greater than 2 indicates a moderate color change.

[0047] In Examples 1 and 2, a tertiary amine photoinitiator with an electron-withdrawing group was used. The molar ratio of the photosensitizer (camphorquinone) to the initiator (tertiary amine) was between 1:1 and 1:2, and the molar ratio of the inhibitor (di-tert-butyl-p-cresol) to the initiator (tertiary amine) was between 1:1 and 1:5. The color difference before and after aging was within 2, indicating very stable color.

[0048] Comparative Example 1 uses a tertiary amine photoinitiator without an electron-withdrawing group, and the color difference before and after aging reaches 6.5, with obvious color change.

[0049] In Comparative Example 2, the molar ratio of the tertiary amine initiator to the photosensitizer camphorquinone is greater than 2:1, and the color difference before and after aging is 3.2, indicating a certain color change.

[0050] In Comparative Example 3, the molar ratio of the tertiary amine initiator to the photosensitizer camphorquinone is less than 1:1, and the molar ratio of the tertiary amine initiator to the inhibitor is greater than 5:1. The color difference before and after aging is 2.8, and there is a certain color change.

[0051] In Comparative Example 4, the molar ratio of the tertiary amine initiator to the inhibitor is less than 1:1, and the color difference before and after aging is 4.4, indicating a certain color change.

[0052] In summary, the light-curing veneer resin cement with high color stability uses a tertiary amine initiator containing an electron-withdrawing group to reduce the electron density of the nitrogen atom through the conjugation effect, thereby inhibiting the occurrence of oxidative side reactions. At the same time, after the tertiary amine is oxidized to generate a nitrogen free radical cation, the electron-withdrawing group can still stabilize the intermediate to prevent it from further decomposing into a colored product, thereby maintaining the color stability of the veneer resin cement at a high level during veneer restoration and maintaining the beauty of the teeth.

[0053] With the above-described preferred embodiments of the present invention as a guide, and with reference to the above description, relevant personnel are fully capable of making various changes and modifications without departing from the technical scope of this invention. The technical scope of this invention is not limited to the contents of the specification and must be determined according to the scope of the claims.

Claims

1. A light-curing veneer resin cement, characterized in that: The following components are included by weight percentage: Acrylate monomer 20% to 40%, photosensitizer 0.03% to 0.3%, photoinitiator 0.03% to 0.3%, inhibitor 0.03% to 0.3%, filler 60% to 80%; Wherein, the photoinitiator is a tertiary amine having an electron-withdrawing group.

2. The light-curing veneer resin cement according to claim 1, characterized in that: The structural formula of the photoinitiator is: ； Wherein, R is an electron-withdrawing group.

3. The light-curing veneer resin cement according to claim 2, characterized in that: The R includes any one of CN, COOH, COOCH3, COOCH2CH3, and COOCH2CH2CH3.

4. The light-curing veneer resin cement according to claim 1, characterized in that: The photoinitiator includes any one or more combinations of 4-dimethylaminobenzoic acid, ethyl 4-dimethylaminobenzoate, and 4-(dimethylamino)benzonitrile.

5. The light-curing veneer resin cement according to claim 1, characterized in that: The acrylate monomer is selected from one or more combinations of acrylic resin monomers containing monofunctional groups, difunctional groups and multifunctional groups; Wherein, the monofunctional group includes hydroxyethyl methacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonadecanyl methacrylate, decyl methacrylate, hydroxyethyl acrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonadecanyl acrylate, decyl acrylate; The bifunctional group includes urethane dimethacrylate, bisphenol A glycidyl dimethacrylate, triethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, 1,8-octanediol diacrylate, 1,10-decanediol diacrylate, 1,12-dodecanediol dimethacrylate; The multifunctional group includes trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and dipentaerythritol pentaacrylate.

6. The light-curing veneer resin cement according to claim 1, characterized in that: The photosensitizer includes camphorquinone.

7. The light-curing veneer resin cement according to claim 1, characterized in that: The inhibitor includes di-tert-butyl-p-cresol.

8. The light-curing veneer resin cement according to claim 1, characterized in that: The filler includes an inert glass powder filler.

9. The light-curing veneer resin cement according to claim 1, characterized in that: The molar ratio of the photosensitizer to the initiator is 1:1 to 1:2; The molar ratio of the inhibitor to the initiator is 1:1 to 1:5.

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