Compositions and methods for treating dental hypersensitivity

Abstract

Disclosed herein are oral care compositions for reducing dental hypersensitivity comprising at least one epoxidized acrylated vegetable oil (e.g., at least one epoxidized acrylated soybean oil) and a photoinitiator system comprising at least one photoinitiator (e.g., camphorquinone or riboflavin). Also disclosed herein are methods of using the oral care composition to reduce or prevent dental hypersensitivity.

Description

COMPOSITIONS AND METHODS FOR TREATING DENTAL HYPERSENSITIVITYCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of priority from U.S. Provisional Patent Application No. 63 / 645,417, filed 10 May 2024, the contents of which are hereby incorporated herein by reference in their entirety.BACKGROUND

[0002] Exposure of dentin may occur, for example, from dental erosion or gingival recession. Dental erosion involves demineralization and damage to the tooth structure due to acid attack from nonbacterial sources. Erosion is found initially in the enamel and, if unchecked, may proceed to the underlying dentin. Generally, saliva has a pH between 7.2 to 7.4. When the pH is lowered and the concentration of hydrogen ions becomes relatively high, the tooth enamel can become microscopically etched, resulting in a porous, sponge-like roughened surface that may cause dentin hypersensitivity, among other problems.

[0003] Dentin hypersensitivity is a painful response to a variety of stimuli, including thermal, tactile, evaporative, osmotic, and chemical stimuli. Dentin is a portion of the tooth internal to the enamel and cementum that has a radially striated appearance owing to a large number of fine canals or tubules known as dentin tubules. Dentin tubules ran from the pulp cavity to the periphery of the dentin and are generally about two microns in diameter at their base and somewhat narrower at their periphery. Dentin tubules are not usually exposed to the environment in the oral cavity, as they are usually covered by enamel or cementum. The cementum in turn is often covered by the gums.

[0004] Exposure of the dentin, which is generally due to recession of the gums, or loss of enamel, frequently leads to hypersensitivity. Changes in the flow of the plasma- like biological fluid present in the dentinal tubules can trigger mechanoreceptors present on nerves located at the pulpal aspect, thereby eliciting a pain response. This hydrodynamic flow can be increased by cold, air pressure, drying, sugar, sour (dehydrating chemicals), or forces acting onto the tooth. Hot or cold food or drinks, and physical pressure are typical triggers in those individuals with teeth sensitivity.

[0005] Conventionally, two approaches have been taken to treat or ameliorate tooth sensitivity. The first approach is to interfere with transmission of nerve impulses. Known desensitizing agents are useful in this chemical approach and may include potassium salts (such as potassium nitrate,potassium bicarbonate, potassium chloride) and strontium, zinc salts, and chloride salts. The second approach involves the mechanical shield of the nerve by, c.g., blocking of the dentin tubules wholly or partially with dentin tubule occlusion agents. For example, argininc-calcium carbonate complexes plug dentinal tubules, providing immediate relief from dentinal hypersensitivity. For example, conventional oral care compositions, such as Colgate Sensitive Pro-Relief®, often include arginine and calcium carbonate as blocking agents to occlude the dentin and reduce sensitivity.

[0006] Dentin hypersensitivity may also be addressed with light-curing systems, typically administered in a professional setting, that coat the surface of the dentin and occlude tubules. Currently, the options available for treating dentin hypersensitivity with light-curing systems rely solely on fully synthetic acrylate materials such as hydroxyethyl methacrylate, urethane dimethacrylate, triethylene glycol methacrylate, and bisphenol A-glycidyl methacrylate. These materials may introduce potential health and / or environmental concerns. There are no light-curing products that utilize a natural-based material as the main component for treating dentin hypersensitivity.

[0007] Accordingly, there still exists a need in the art for an oral care composition, which upon use, provides enhanced prevention or reduction of tooth sensitivity and is formulated for application to the oral cavity in a convenient form for providing substantially immediate relief over a period of time that is free from health concerns and safe for the environment.BRIEF SUMMARY

[0008] This summary is intended merely to introduce a simplified summary of some aspects of one or more implementations of the present disclosure. Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. This summary is not an extensive overview, nor is it intended to identify key elements of the present teachings, nor to delineate the scope of the disclosure. Rather, its purpose is merely to present one or more concepts in simplified form as a prelude to the detailed description below.

[0009] Aspects disclosed herein are directed to an oral care composition for reducing dental hypersensitivity, the composition comprising at least one epoxidized acrylated vegetable oil and a photoinitiator system comprising at least one photoinitiator. In certain embodiments, the oral carecomposition is a gel, e.g., an oleogel, that is capable of curing to a semi-solid state upon exposure to light.

[0010] In certain embodiments of the oral care composition disclosed herein, the epoxidized acrylated vegetable oil is derived from a vegetable oil selected from soybean oil, palm oil, rapeseed oil, sunflower oil, and in certain embodiments, the epoxidized acrylated vegetable oil is an epoxidized acrylated soybean oil. In certain embodiments, the epoxidized acrylated vegetable oil (e.g., epoxidized acrylated soybean oil) is present in the oral care composition in an amount ranging from about 75 wt% to about 99.95 wt%, such as from about 95 wt% to about 99.95 wt%, based on the total weight of the oral care composition.

[0011] According to various embodiments of the oral care composition disclosed herein, the at least one photoinitiator is selected from alpha-diketones, such as camphorquinone and 1-phenyl- 1,2-propane dione; bisacyl phosphine oxides, such as bis(2,4,6-trimethylbenzoyl)- phenylphosphine oxide and 2,4,6-trimethylbenzoyl diphenylphosphine oxide; alphaaminoalky Iphenones, such as 2-benzyl-2-dimethylamino-l-(4-morpholinophenyl)-butanone-l and 2-methyl-l-(4-methylthiophenyl)-2-morpholinopropane-l-one; and titanocenes, such as bis(q5- 2,4-cyclopentadiene-l-yl)-bis(2,6-difluoro-3-(lH-pyrrole-l-yl)phenyl) titanium; benzoin methyl ether; 1 -hydroxy cyclohexylphenyl ketone; and combinations thereof. In certain embodiments, the at least one photoinitiator is camphorquinone. According to certain embodiments, the at least one photoinitiator (e.g., camphorquinone) is present in the oral care composition in an amount ranging from about 0.01 wt% to about 1 wt%, such as from about 0.2 wt% to about 0.8 wt%, about 0.4 wt% to about 0.6 wt%, or about 0.5 wt%, based on the total weight of the oral care composition.

[0012] According to various aspects disclosed herein, the at least one photoinitiator is water- soluble. In certain embodiments, the at least one photoinitiator is selected from riboflavin, eosin, eosin Y, fluorescein, Rose Bengal, potassium persulfate, ammonium persulfate, sodium persulfate, and combinations thereof, and in certain embodiments, the at least one photoinitiator is riboflavin. According to certain embodiments, the at least one photoinitiator (e.g., riboflavin) is present in the oral care composition in an amount ranging from about 0.001 wt% to about 0.1 wt%, such as about 0.002 wt% to about 0.008 wt%, about 0.004 wt % to about 0.006 wt%, or about 0.005 wt%, based on the total weight of the oral care composition.

[0013] According to certain embodiments disclosed herein, the photoinitiator system further comprises at least one co-initiator, and in certain embodiments, the at least one co-initiator is L-arginine. In certain embodiments, the at least one co-initiator is present in the oral care composition in an amount ranging from about 0.01 wt% to about 1 wt%, such as from about 0.1 wt% to about 0.8 wt%, about 0.4 wt% to about 0.6 wt%, or about 0.5 wt%.

[0014] In certain embodiments disclosed herein, the oral care composition further comprises water, and in certain embodiments, water is present in the oral care composition in an amount ranging from about 1 wt% to about 10 wt%, such as from about 2 wt% to about 8 wt%, about 4 wt% to about 6 wt%, about 5 wt%, or about 4.995 wt%.

[0015] Also disclosed herein is an oral care composition for reducing dental hypersensitivity (e.g., a gel such as an oleogel) consisting of at least one epoxidized acrylated vegetable oil and a photoinitiator system comprising at least one photoinitiator. In certain embodiments, the oral care composition consists of at least one epoxidized acrylated soybean oil and a photoinitiator system comprising at least one photoinitiator, and in certain embodiments, the photoinitiator system consists of camphorquinone. In yet other embodiments disclosed herein, the photoinitiator system consists of riboflavin, L-arginine, and water.

[0016] Also disclosed herein are methods of reducing or preventing dental hypersensitivity in a subject in need thereof, the method comprising applying to the oral care composition disclosed herein to a surface of the teeth of the subject. In certain embodiments, the method further comprises applying light to the surface of the teeth after applying the oral care composition. In certain embodiments, the light has a wavelength ranging from about 380 nm to about 500 nm, such as from about 400 nm to about 500 nm or about 440 nm to about 470 nm. According to certain embodiments, the light is applied to the surface of the teeth for at least about 15 seconds, such as at least about 30 seconds, at least about 45 seconds, or at least about one minute.

[0017] In certain embodiments of the methods disclosed herein, the method occludes (partially or wholly) at least about 50% of exposed dentin tubules, such as at least about 75%, at least about 85%, or at least about 90% of exposed dentine tubules.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Implementation of the present technology will now be described, by way of example only, with reference to the attached figures. The features and advantages of the disclosure will be apparent from the following more detailed description of certain embodiments and as illustrated in the accompanying drawings in which:

[0019] FIG. 1 shows the chemical formula for an exemplary epoxidized acrylated soybean oil as disclosed herein.

[0020] FIG. 2A are microscope images showing the first three of six testing spots on Dentin S before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0021] FIG. 2B are microscope images showing the second three of six testing spots on Dentin S before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0022] FIG. 3A are microscope images showing the first three of six testing spots on Dentin U before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0023] FIG. 3B are microscope images showing the second three of six testing spots on Dentin U before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0024] FIG. 4A are microscope images showing the first three of six testing spots on Dentin V before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0025] FIG. 4B are microscope images showing the second three of six testing spots on Dentin V before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0026] FIG. 5A are microscope images showing the first three of six testing spots on Dentin W before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0027] FIG. 5B are microscope images showing the second three of six testing spots on Dentin W before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0028] FIG. 6A are microscope images showing the first three of six testing spots on Dentin X before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0029] FIG. 6B are microscope images showing the second three of six testing spots on Dentin X before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0030] FIG. 7A are microscope images showing the first three of six testing spots on Dentin Z before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0031] FIG. 7B are microscope images showing the second three of six testing spots on Dentin Z before (top) and after (bottom) treatment with the oral care composition, as disclosed in Example 2.

[0032] FIG. 8 are cross-sectional scanning electron microscope (SEM) images of an untreated dentin slice (left) containing empty tubules and a treated dentin slice (right) showing the tubules cured with the oral care composition disclosed herein, as disclosed in Example 2.DETAILED DESCRIPTION

[0033] For illustrative purposes, the principles of the present disclosure are described by referencing various exemplary embodiments thereof. Although certain embodiments of the disclosure are specifically described herein, one of ordinary skill in the art will readily recognize that the same principles are equally applicable to, and can be employed in other compositions and methods. Before explaining the disclosed embodiments of the present disclosure in detail, it is to be understood that the disclosure is not limited in its application to the details of any particular embodiment disclosed herein. The terminology used herein is for the purpose of description and not of limitation.

[0034] As used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural references unless the context dictates otherwise. The singular form of any class of the ingredients refers not only to one chemical species within that class, but also to a mixture of those chemical species. The terms “a” (or “an”), “one or more” and “at least one” may be used interchangeably herein. The terms “comprising”, “including”, and “having” may be used interchangeably. The term “include” should be interpreted as “include, but are not limited to”. The term “including” should be interpreted as “including, but are not limited to”.

[0035] As used throughout, ranges are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. Thus,a range from 1 -5, includes specifically 1 , 2, 3, 4 and 5, as well as subranges such as 2-5, 3-5, 2-3, 2-4, 1-4, etc.

[0036] The term “about” when referring to a number means any number within a range of 10% of the number. For example, the phrase “about 2 wt.%” refers to a number between and including 1.8 wt.% and 2.2 wt.%.

[0037] All references cited herein are hereby incorporated by reference in their entireties. In the event of a conflict in a definition in the present disclosure and that of a cited reference, the present disclosure controls.

[0038] The abbreviations and symbols as used herein, unless indicated otherwise, take their ordinary meaning. The abbreviation “wt.%” means percent by weight with respect to the oral care composition. The symbol “°” refers to a degree, such as a temperature degree or a degree of an angle. The symbols “h”, “min”, “mL”, “nm”, and “pm” refer to hour, minute, milliliter, nanometer, and micrometer, respectively. The abbreviation “rpm” means revolutions per minute.

[0039] When referring to chemical structures and names, the symbols “C”, “H”, and “O” mean carbon, hydrogen, and oxygen, respectively. The symbols “=”, and “=” mean single bond, double bond, and triple bond, respectively.

[0040] Any member in a list of species that are used to exemplify or define a genus may be mutually different from, or overlapping with, or a subset of, or equivalent to, or nearly the same as, or identical to, any other member of the list of species. Further, unless explicitly stated, such as when reciting a Markush group, the list of species that define or exemplify the genus is open, and it is given that other species may exist that define or exemplify the genus just as well as, or better than, any other species listed.

[0041] The phrases, “a mixture thereof,” “a combination thereof,” or a combination of two or more thereof’ do not require that the mixture include all of A, B, C, D, E, and F (although all of A, B,C, D, E, and F may be included). Rather, it indicates that a mixture of any two or more of A, B, C,D, E, and F can be included. In other words, it is equivalent to the phrase “one or more elements selected from the group consisting of A, B, C, D, E, F, and a mixture of any two or more of A, B, C, D, E, and F.” Likewise, the term “a salt thereof” also relates to “salts thereof.” Thus, where the disclosure refers to “an element selected from the group consisting of A, B, C, D, E, F, a salt thereof, and a mixture thereof,” it indicates that that one or more of A, B, C, D, and F may be included, one or more of a salt of A, a salt of B, a salt of C, a salt of D, a salt of E, and a salt of Fmay be included, or a mixture of any two of A, B, C, D, E, F, a salt of A, a salt of B, a salt of C, a salt of D, a salt of E, and a salt of F may be included.

[0042] All components and elements positively set forth in this disclosure can be negatively excluded from the claims. In other words, the oral care compositions of the instant disclosure can be free or essentially free of all components and elements positively recited throughout the instant disclosure. In some instances, the oral care compositions of the present disclosure may be substantially free of non-incidental amounts of the ingredient(s) or compound(s) described herein. A non-incidental amount of an ingredient or compound is the amount of that ingredient or compound that is added into the oral care composition by itself. For example, an oral care composition may be substantially free of a non-incidental amount of an ingredient or compound, although such ingredient(s) or compound(s) may be present as part of a raw material that is included as a blend of two or more compounds.

[0043] Some of the various categories of components identified may overlap. In such cases where overlap may exist and the oral care composition includes both components (or the composition includes more than two components that overlap), an overlapping compound does not represent more than one component. For example, certain compounds may be characterized as both a polyol and a sweetener. If a particular oral care composition includes both a polyol and a sweetener, compound will serve only as either a polyol or a sweetener — not both.

[0044] For readability purposes, the chemical functional groups are in their adjective form; for each of the adjectives, the word “group” is assumed. For example, the adjective “alkyl” without a noun thereafter, should be read as “an alkyl group.”

[0045] As used herein, the term “subject” refers to individuals (e.g., human) to be treated by the methods or compositions of the present invention. Subjects include, but are not limited to, mammals (e.g., murines, simians, equines, bovines, porcines, canines, felines, and the like), and most preferably includes humans.

[0046] As used herein the term, “in vitro” refers to an artificial environment and to processes or reactions that occur within an artificial environment. In vitro environments include, but are not limited to, test tubes and cell cultures. The term “in vivo” refers to the natural environment (e.g., an animal or a cell) and to processes or reaction that occur within a natural environment.

[0047] Disclosed herein are oral care compositions comprising a naturally-derived epoxidized acrylated vegetable oil (EAVO), such as an epoxidized acrylated soybean oil (EASO), and aphotoinitiator system comprising at least one photoinitiator, e.g. camphorquinone or riboflavin. The EAVO (e.g., EASO) is capable of transitioning from a liquid to a gcl-likc solid when paired with the photoinitiator system and exposed to an appropriate light source. When the compositions disclosed herein are applied to a surface of exposed dentin tissue, the EAVO in liquid form is able to penetrate into the dentin tubule network before it is cured with the light. Once cured, the solid gel forms a physical barrier that prevents external stimulus from reaching nerves inside the tissue, thereby reducing dental hypersensitivity.

[0048] The methods disclosed herein for treating dental hypersensitivity use a modified vegetable oil (e.g., modified soybean oil) that is capable of providing a similar mode of action to current dental resins that rely on synthetic compounds. When the EAVO (e.g., EASO) and the suitable light-curing compound, e.g. camphorquinone or riboflavin, arc combined in the correct ratio, a chemical reaction can occur when the composition is irradiated with an appropriate wavelength of light, e.g., about 440 nm. This chemical reaction leads to the formation of a network of new bonds within the EAVO that convert the composition from a free-flowing liquid to a rigid oil-based gel, i.e., an oleogel. In certain embodiments, the oleogel is formed within one minute of the light exposure.

[0049] The oral care compositions disclosed herein may be provided in any form suitable for oral administration and application to the surface of teeth. For example, the oral care composition may be in the form of a solid, a liquid, a toothpaste, or a gel. In certain embodiments, the oral care composition is a gel. In certain embodiments, the oral care composition is in the form of an oleogel. As used herein, an oleogel indicates a gel comprising mainly oil. Oleogels may have a semisolid consistency and be transparent, translucent, or colored, e.g., white. According to certain embodiments, the oral care composition disclosed herein is completely biodegradable, and in certain embodiments, the oral care composition comprises or consists of naturally-derived materials.Epoxidized Acrylated Vegetable Oils

[0050] In embodiments of the disclosure, the oral care composition comprises at least one epoxidized acrylated vegetable oil (EAVO), such as an epoxidized acrylated soybean oil (EASO). EAVO is derived from a vegetable oil that is epoxidized to introduce epoxy groups into the molecular structure of the oil. The epoxy groups serve to enhance the oil’s reactivity and functionality. The epoxidized vegetable oil may then be acrylated to produce an EAVO. Acrylationinvolves the addition of acrylic or methacrylic functional groups to the epoxidized vegetable oil, which further enhances the functionality of the EAVO, including by improving, for example, the adhesion, flexibility, and chemical resistance of the EAVO. In certain embodiments, the EAVO is biodegradable. In recent years, there has been a growing trend of using vegetable oils, e.g., soybean oil, as a renewable resource for chemical production.

[0051] EAVO has been used, for example, as a renewable and environmentally friendly alternative to conventional petroleum-based products, such as coatings, sealants, adhesives, and composite materials. Any suitable vegetable oil may be used in the embodiments disclosed herein. In certain embodiments, the EAVO is derived from a vegetable oil selected from soybean oil, palm oil, rapeseed oil, sunflower oil, or other triglyceride oils. In certain embodiments, the EAV O is derived from soybean oil to form an epoxidized acrylated soybean oil (EAVO).

[0052] In certain embodiments, the vegetable oil (e.g., soybean oil) is epoxidized with the use of an organic peroxy acid, such as performic acid or peracetic acid. In certain embodiments, the organic acid may be produced in the reaction in situ through the addition of hydrogen peroxide and the organic acid, e.g., formic acid or acetic acid. After epoxidation, the vegetable oil may then be acrylated, e.g., with acrylic acid, to form an acrylated epoxidized soybean oil. An exemplary epoxidized acrylated soybean oil is shown in Figure 1. The EAVOs disclosed herein, including EASO, may be used as polymerizable monomers in an oleogel system comprising a photoinitiator system, wherein the oleogel system is cured by a light source.

[0053] In certain embodiments, the EAVO (e.g., EASO) is present in the oral care composition disclosed herein in an amount ranging from about 1 wt% to about 99.95 wt%, such as from about 50 wt% to about 99.95 wt%, about 75 wt% to about 99.95 wt%, about 90 wt% to about 99.95 wt%, about 91 wt% to about 99.95 wt%, about 92 wt% to about 99.95 wt%, about 93 wt% to about 99.95 wt%, about 94 wt% to about 99.95 wt%, about 95 wt% to about 99.95 wt%, about 96 wt% to about 99.95 wt%, about 97 wt% to about 99.95 wt%, about 98 wt% to about 99.95 wt%, about 99 wt% to about 99.95 wt%, about 99.5 wt% to about 99.95 wt%, or about 99.75 wt% to about 99.95 wt%, or about 99.95 wt%, based on the total weight of the oral care composition. In certain embodiments, the EAVO (e.g., EASO) is present in the oral care composition disclosed herein in an amount ranging from 1 wt% to about 95 wt%, such as from about 50 wt% to about 95 wt%, about 75 wt% to about 95 wt%, about 90 wt% to about 95 wt%, about 91 wt% to about 95 wt%,about 92 wt% to about 95 wt%, about 93 wt% to about 95 wt%, or about 94 wt% to about 95 wt%, or about 95 wt%, based on the total weight of the oral care composition.Photoinitiator system

[0054] In embodiments disclosed herein, the oral care composition comprises at least one photoinitiator system or catalyst that enables the oral care composition to harden, e.g., through polymerization or crosslinking. For example, visible light and / or near infrared photoinitiator systems may be used to initiate photopolymerization in the oral care compositions disclosed herein. As used herein, a photoinitiator is a molecule that creates a reactive species, such as a free radical, upon exposure to radiation wavelengths in the ultraviolet (UV) or visible light spectrum. In certain embodiments, the wavelength of the light irradiated for the polymerization and curing is in the visible light region, e.g., about 380 nm to about 500 nm, such about 400 nm to about 500 nm. The appropriate wavelength may be chosen based upon the known wavelength reactivity of the selected photoinitiator or photoinitiators in the photoinitiator system.

[0055] Any known photoinitiator may be used in the oral care compositions disclosed herein. Exemplary photoinitiators may include phosphine oxide; peroxides; peracids; azide compounds; a-hydroxy ketones, or a-aminoketones. In certain embodiments, the at least one photoinitiator is selected from alpha-diketones, such as camphorquinone and 1 -phenyl- 1,2-propane dione; xanthenes such as fluorescein; bisacyl phosphine oxides, such as bis(2,4,6-trimethylbenzoyl)- phenylphosphine oxide and 2,4,6-trimethylbenzoyl diphenylphosphine oxide; alphaaminoalky Iphenones, such as 2-benzyl-2-dimethylamino-l-(4-morpholinophenyl)-butanone-l and 2-methyl-l-(4-methylthiophenyl)-2-morpholinopropane-l-one; and titanocenes, such as bis(q5- 2,4-cyclopentadiene-l-yl)-bis(2,6-dilluoro-3-(lH-pyrrole-l-yl)phenyl) titanium; benzoin methyl ether; 1-hydroxycyclohexylphenyl ketone; photoinitiators sold under the brand name of DAROCURE®, such as DAROCURE® 1173, or photoinitiators sold under the brand name of IRGACURE®, such as IRGACURE® 2959, IRGACURE® 651, IRGACURE® 819, and IRGACURE® 184. In certain embodiments, the photoinitiator system comprises camphorquinone, and in certain embodiments, the photoinitiator system consists of camphorquinone. The excitation maximum absorption wavelength of camphorquinone is about 470 nm.

[0056] In certain embodiments disclosed herein, the photoinitiator system comprises at least one photoinitiator and at least one co-initiator. In certain embodiments, the photoinitiator system comprises a water-soluble photoinitiator. In certain embodiments, the water-soluble photoinitiatoris selected from riboflavin, eosin, eosin Y, xanthene dyes such as Rose Bengal, potassium persulfate, ammonium persulfate, sodium persulfate, and combinations thereof. In certain embodiments, the photoinitiator is riboflavin.

[0057] In certain embodiments, the at least one photoinitiator is an oil-soluble photoinitiator. In certain embodiments, the oil-soluble photoinitiator may be selected from organic peroxides or azo compounds. Exemplary organic peroxides include ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, peroxyesters, and combinations thereof, including, for example, lauroyl peroxide, l,l-bis(t-hexylperoxy)-3,3,5- trimethylcyclohexane, 1 , l-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, t-butylperoxylaurate, t- butylperoxyisopropylmonocarbonate, t-butylperoxy-2-ethylhexylcarbonate, di-t- butylperoxyhexahydro-terephthalate, dicumyl peroxide, 2,5-dimethyl-2,5-di(t- butylperoxy)hexane, di-t-butyl peroxide, t-butylperoxy-2-ethylhexanoate, bis(4-t- butylcyclohexyl)peroxydi-carbonate, t-amylperoxy-3,5,5-trimethylhexanoate, 1 , l-di(t- amylperoxy)-3,3,5-trimethylcyclohexane, benzoyl-peroxide, t-butylperoxyacetate, and combinations thereof.

[0058] In certain embodiments, the photoinitiator system may comprise at least one co-initiator. A co-initiator can be used in combination with any of the photoinitiators described herein. In one aspect, the co-initiator is 2-(diethylamino)ethyl acrylate, 2-(dimethylamino)ethyl acrylate, 2- (dimethylamino)ethyl benzoate, 2-(dimethylamino)ethyl methacrylate, 2-ethylhexyl 4- (dimethylamino)benzoate, 3-(dimethylamino)propyl acrylate, 4,4'- bis(diethylamino)benzophenone, or 4-(diethylamino)benzophenone. In certain embodiments, the at least one co-initiator is an electron donor, such as L-arginine.

[0059] In certain embodiments of the disclosure, the photoinitiator system in the oral care composition disclosed herein comprises riboflavin and at least one co-initiator. In certain embodiments, the photoinitiator system in the oral care composition disclosed herein comprises riboflavin and L-arginine, and in certain embodiments, the photoinitiator system in the oral care composition disclosed herein consists of riboflavin and L-arginine or consists of riboflavin, L- arginine, and water.

[0060] The at least one photoinitiator may be present in the oral care compositions disclosed herein in any effective amount, i.e., any amount effective to initiate photopolymerization of the at least one epoxidized acrylated vegetable oil. In certain embodiments, the at least one photoinitiator ispresent in the oral care composition in an amount ranging from about 0.001 wt% to about 10 wt%, such as from about 0.001 wt% to about 5 wt%, about 0.001 wt% to about 1 wt%, about 0.001 wt% to about 0.5 wt%, about 0.001 wt% to about 0.1 wt%, about 0.001 wt% to about 0.05 wt%, about 0.001 wt% to about 0.01 wt%, or about 0.001 wt% to about 0.005 wt%; from about 0.002 to about 10 wt%, such as from about 0.002 wt% to about 5 wt%, about 0.002 wt% to about 1 wt%, about 0.002 wt% to about 0.5 wt%, about 0.002 wt% to about 0.1 wt%, about 0.002 wt% to about 0.05 wt%, about 0.002 wt% to about 0.01 wt%, or about 0.002 wt% to about 0.005 wt%; from about 0.005 wt% to about 10 wt%, such as from about 0.005 wt% to about 5 wt%, about 0.005 wt% to about 1 wt%, about 0.005 wt% to about 0.5 wt%, about 0.005 wt% to about 0.1 wt%, about 0.005 wt% to about 0.05 wt%, about 0.005 wt% to about 0.01 wt%, or about 0.005 wt% to about 0.007 wt%; from about 0.01 wt% to about 5 wt%, about 0.01 wt% to about 1 wt%, about 0.01 wt% to about 0.5 wt%, about 0.01 wt% to about 0.1 wt%, about 0.01 wt% to about 0.05 wt%; from about 0.05 wt% to about 5 wt%, about 0.05 wt% to about 1 wt%, about 0.05 wt% to about 0.5 wt%, about 0.05 wt% to about 0.1 wt%, about 0.05 wt% to about 0.07 wt% based on the total weight of the oral care composition. In certain embodiments the at least one photoinitiator is camphorquinone, and in certain embodiments the camphorquinone is present in the oral care composition is an amount of about 0.05 wt%, based on the total weight of the oral care composition. In certain embodiments, the at least one photoinitiator is riboflavin, and in the certain embodiments, the riboflavin is present in the oral care composition in an amount of about 0.005 wt%, based on the total weight of the oral care composition.

[0061] When present, the at least one co-initiator may be present in the oral care composition in any effective amount, i.e., any amount effective to co-initiate photopolymerization of the at least one epoxidized acrylated vegetable oil. In certain embodiments, the at least one co-initiator is present in the oral care composition disclosed herein in an amount ranging from about 0.001 wt% to about 10 wt%, such as from about 0.001 wt% to about 5 wt%, about 0.001 wt% to about 1 wt%, about 0.001 wt% to about 0.5 wt%; from about 0.002 to about 5 wt%, such as from about 0.002 wt% to about 1 wt%, about 0.002 wt% to about 0.5 wt%; from about 0.005 wt% to about 5 wt%, about 0.005 wt% to about 1 wt%, about 0.005 wt% to about 0.5 wt%; from about 0.01 wt% to about 5 wt%, about 0.01 wt% to about 1 wt%, about 0.01 wt% to about 0.5 wt%; from about 0.05 wt% to about 5 wt%, about 0.05 wt% to about 1 wt%, or about 0.05 wt% to about 0.5 wt%, about 0.5 wt% to about 0.7 wt%, or about 0.5 wt%, based on the total weight of the oral carecomposition. Tn certain embodiments of the disclosure, the at least one co-initiator is L-arginine, and in certain embodiments, the L-argininc is present in the oral care composition in an amount of about 0.5 wt%, based on the total weight of the composition.Water

[0062] In certain embodiments, the oral care composition disclosed herein comprises water, and in certain embodiments, the oral care composition disclosed herein is anhydrous. For instance, in embodiments wherein the at least one photo-initiator is water-soluble, the oral care composition may comprise water. When present, water may be included in the oral care composition in any effective amount. In certain embodiments, water may be present in the oral care composition in an amount ranging from about 0.1 wt% to about 20 wt%, such as from about 0.1 wt% to about 15 wt%, about 0.1 wt% to about 10 wt%, about 0.1 wt% to about 5 wt%; about 0.5 wt% to about 20 wt%, such as from 0.5 wt% to about 15 wt%, about 0.5 wt% to about 10 wt%, about 0.5 wt% to about 5 wt%; about 1 wt% to about 20 wt%, such as from about 1 wt% to about 15 wt%, about 1 wt% to about 10 wt%, about 1 wt% to about 5 wt%; from about 1.5 wt% to about 20 wt%, such as from about 1.5 wt% to about 15 wt%, about 1.5 wt% to about 10 wt%, about 1.5 wt% to about 5 wt%; from about 2 wt% to about 20 wt%, such as from 2 wt% to about 2 wt%, about 2 wt% to about 10 wt%, about 2 wt% to about 5 wt%; from about 3 wt% to about 20 wt%, such as from 3 wt% to about 15 wt%, about 3 wt% to about 10 wt%, about 3 wt% to about 5 wt%; from about 4 wt% to about 20 wt%, such as from 4 wt% to about 15 wt%, about 4 wt% to about 10 wt%, about 4 wt% to about 5 wt%, from about 4.5 wt% to about 20 wt%, such as from about 4.5 wt% to about 15 wt%, about 4.5 wt% to about 10 wt%, about 4.5 wt% to about 5 wt%, about 4.5 wt%, or 4.495 wt%. based on the total weight of the composition. In certain embodiments, the oral care composition comprises less than about 1 wt% water, such as less than about 0.5 wt%, less than about 0.1 wt%, less than about 0.01 wt%, or less than about 0.001 wt%, based on the total weight of the composition. In certain embodiments, the oral care composition is free of or substantially free of water.Other Ingredients

[0063] The oral care composition disclosed herein may comprise any other ingredients suitable for incorporation in an oral care composition. For example, in certain embodiments the oral care compositions disclosed herein may further include one or more active agents selected from at least one fluoride agent, such as sodium monofluorophosphate, stannous fluoride, calcium fluoride,strontium fluoride, zinc fluoride, zinc potassium fluoride, ammonium fluoride, potassium magnesium fluoride, and combinations thereof; at least one whitening agent, at least one anticalculus and / or antiplaque agent, at least one remineralization agent, at least one stannous sources, at least one antimicrobial agent, at least one antioxidant, at least one breath freshening agent, at least one additional agent for reducing hypersensitivity, at least one nutrient, and combinations thereof.

[0064] In certain embodiments, the oral care composition disclosed herein comprises at least one whitening agent. Exemplary whitening agents may be selected from peroxide whitening agents, non-peroxide whitening agents, titanium dioxide, hydroxyapatite, or a combination thereof. Peroxide whitening agents may be selected from hydrogen peroxide, alkali or alkaline earth metal peroxides (e.g., sodium peroxide, potassium peroxide, lithium peroxide, magnesium peroxide, calcium peroxide, or barium peroxide), glyceryl hydrogen peroxide, alkyl hydrogen peroxide, dialkyl peroxide, peroxy acids, peroxy acid salts, benzoyl peroxide, urea peroxide, and combinations thereof. Non-peroxide whitening agents may be selected from chlorine dioxide, chlorites, and hypochlorites. In certain embodiments, the oral care composition disclosed herein is free of or substantially free of a whitening agent.

[0065] In certain embodiments, the oral care composition disclosed herein further comprises at least one anticalculus or antiplaque agent. Suitable anticalculus agents may be selected from, for example, phosphates, polyphosphates, such as pyrophosphates, polyolefin sulfonates, polyolefin phosphates, diphosphonates, phosphonoalkane carboxylic acids, and salts thereof, typically alkali metal or ammonium salts. Suitable antiplaque agents may be selected from, for example, tannous salts, salts of copper, magnesium or strontium, dimethicone copolyols, such as cetyl dimethicone copolyol, papain, glucamylase, glucose oxidase, urea, calcium lactate, calcium glycerophosphate, strontium polyacrylates, and combinations thereof.

[0066] In certain embodiments, the oral care composition disclosed herein further comprises at least one remineralization agent. Exemplary remineralization agents that may be incorporated into the oral care composition disclosed herein include calcium phosphate (e.g., mono-, di-, and / or tricalcium phosphate), hydroxyapatite, calcium carbonate, calcium chloride, calcium nitrate, calcium gluconate, calcium lactate gluconate, calcium acetate, and combinations thereof.

[0067] In certain embodiments, the oral care composition disclosed herein further comprises at least one desensitizing agent in addition to the EAVO, e.g., EASO. In certain embodiments, the atleast one additional desensitizing agent may be selected from potassium citrate, potassium chloride, potassium tartrate, potassium bicarbonate, potassium oxalate, potassium nitrate, strontium salts, arginine, acetyl salicylic acid or salts thereof, salicylic acid or salts thereof, codeine, acetaminophen, and combinations thereof.Methods

[0068] Disclosed herein are methods of using the oral care composition, e.g., a method of reducing or preventing dental hypersensitivity. In certain embodiments, the method comprises administering the oral care composition disclosed herein to the oral cavity of a subject in need thereof. In certain embodiments, the oral care composition may be administered to the surface of the teeth. The oral care composition may be administered in any way known in the art to deliver an appropriate amount of the oral care composition to the surface of the teeth. For example, the oral care composition can be administered by use of a syringe, a brush, a film, an applicator wand, a finger, a glove, a wipe, a cloth, or direct application from the container of the oral care composition.

[0069] In certain embodiments of the method of reducing or preventing dental hypersensitivity, the method further comprises curing the oral care composition after application. The oral care composition may be cured using any effective means, such as exposing the composition to a suitable light source. A suitable light source may include any light that emits a visible or UV wavelength suitable for activating the photoinitiator system in the oral care composition, including a dental light, a flashlight, or regular household lighting. In certain embodiments, the light source delivers visible light in the range of about 380 nm to about 500 nm, such about 400 nm to about 500 nm, or from about 440 nm to about 470 nm.

[0070] The light may be applied to the oral care composition disclosed herein for a suitable period of time to allow sufficient curing of the oral care composition. In certain embodiments, the light may be applied to the oral care composition for at least about 10 seconds, such as at least about 15 seconds, at least about 20 seconds, at least about 30 seconds, at least about 45 seconds, at least about 1 minute, at least about 1.5 minutes, or at least about 2 minutes. In certain embodiments, the light may be applied to the oral care composition for less than about 5 minutes, such as less than about 4 minutes, less than about 3 minutes, less than about 2 minutes, or less than about 1 minutes. In certain embodiments, light may be applied to the oral care composition for about 15 seconds toabout 3 minutes, such as from about 30 seconds to about 2.5 minutes, or from about 1 minute to about 2 minutes.

[0071] In certain embodiments of the methods disclosed herein, after application of the light source and curing of the oral care composition to the surface of the teeth, the method provides for occlusion of at least about 25% of the exposed dentin tubules, such as at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, or at least about 95% occlusion of the exposed dentin tubules.

[0072] The oral care compositions disclosed herein may be made according to methods and procedures known to those skilled in the art.EXAMPLESExample 1 - Formation of an Oleogel

[0073] Two dental compositions were prepared. The first comprised EASO in an amount of 99.95 wt% and camphorquinone in an amount of 0.05 wt% (Composition A). A second formulation comprised EASO in an amount of 95 wt%, riboflavin in an amount of 0.005 wt%, L-arginine in an amount of 0.5 wt%, and deionized water in an amount of 4.495 wt% (Composition B).

[0074] The ability of each formulation to form an oleogel was tested by dispensing about 0.7 mL of the oil mixture into a cylindrical well with dimensions of 10 mm x 2 mm, and the formulations were irradiated with a dental lamp for either 1 minute or 2 minutes. After curing, the compressive strength of each sample was measured using a Texture Analyzer. The settings for the Texture Analyzer were as follows:Test mode - CompressionPre-test speed - 0.1 mm / sTest speed - 0.1 mm / sPost-test speed - 0.1 mm / sTarget mode - DistanceDistance - 0.3 mmTrigger type - (Auto) ForceTrigger force - 1.0 gProbe - 14 inch spherical stainless steel TA-8

[0075] Tests on each cured sample were performed three times before taking the average value. A total of 25 samples of Composition A were tested, and 27 samples of Composition B were tested. The average of the results for Composition A was 158.66 g, with a standard deviation of 34.30. The average of the results for Composition B was 33.55 g, with a standard deviation of 7.96. A sample of uncured EASO was also tested with the Texture Analyzer, but no force was measured by the probe.

[0076] The results from the Texture Analyzer indicate the ability of the tested formulation for each of Composition A and Composition B to create new bonds / connections within itself to successfully solidify into a structured oleogel.Example 2 - In vitro Application of Dental Composition

[0077] The Composition A prepared in Example 1 comprising EASO and camphorquinone was applied to prepared dentin slices to evaluate its effectiveness in occluding the exposed tubules. Dentin slices were prepared following previous established methods. Briefly, sound human molars were cut laterally to produce slices with a thickness of about 700 qm. Slices with exposed dentin were then polished before being etched in citric acid for 30-40 seconds. Finally, the dentin slices were sonicated in deionized water to clean the surfaces.

[0078] The prepared dentin was imaged under a Leica confocal microscope to determine the baseline area of the open tubules. The disks were then treated through the following steps. Composition A comprising EASO and camphorquinone was rubbed onto the surface of the dentin for 30 seconds in a circular motion with a microtip applicator. Excess material was removed from the surface using a flat edge silicon brush. A dental lamp was applied for one minute. Uncured oil was removed by cleaning the surface with a Kimwipe. Treated samples were then placed in 15 mL of PBS and gently stirred for 15 minutes. Finally, the slices were removed from the PBS and dried with a Kimwipe.

[0079] Treated samples were imaged again under the Leica confocal microscope to measure the difference in area of opened tubules. A total of 6 dentin slices were selected (labelled as Dentin S, Dentin U, Dentin V, Dentin W, Dentin X, and Dentin Z), each with 6 spots for analysis. After treating and imagining the slices, the areas of the open tubules were compared for each spot to determine the total percentage of occlusion. The results are shown in Tables 2-7 for each of the 6 dentin slices.

[0080] Table 2 - Dentin S

[0081] Table 3 - Dentin U

[0082] Table 4 - Dentin V

[0083] Table 5 - Dentin W

[0084] Table 6 - Dentin X

[0085] Table 7 - Dentin Z

[0086] As shown, across the majority of spots sampled across the dentin slice, a high percentage of the tubules were filled with the cured oleogel. The oil was able to penetrate inside the exposed tubules before being cured so that even if the top layer is removed, there is still more inside to block anything else from entering the cavity. The penetration of the formula into the tubules can also be seen with cross-sectional images of the treated dentin taken with a scanning electron microscope (SEM), as shown in Figures 2A-7B, wherein Figures 2A-2B show the 6 spots tested for Dentin S; Figures 3A-3B show the 6 spots tested for Dentin U; Figures 4A-4B show the 6 spots tested for Dentin V; Figures 5A-5B show the 6 spots tested for Dentin W; Figures 6A-6B show the 6 spots tested for Dentin X; and Figures 7A-7B show the 6 spots tested for Dentin Z. It was observed that the formula was able to fill the network of dentin tubules and cure into an oleogel at the surface and deep within the tubes.

[0087] Figure 8 shows a cross-sectional SEM of an untreated dentin slice (left) containing empty tubules and a treated dentin slice (right) showing the tubules cured with the Composition A and a treatment / surface layer on the top of the dentin slice occluding the tubule.

Claims

CLAIMSWhat Is Claimed Is:

1. An oral care composition for reducing dental hypersensitivity comprising: at least one epoxidized acrylated vegetable oil; and a photoinitiator system comprising at least one photoinitiator.

2. The oral care composition according to claim 1 , wherein the epoxidized acrylated vegetable oil is derived from a vegetable oil selected from soybean oil, palm oil, rapeseed oil, or sunflower oil.

3. The oral care composition according to claim 1 or 2, wherein the epoxidized acrylated vegetable oil is an epoxidized acrylated soybean oil.

4. The oral care composition according to any one of the preceding claims, wherein the epoxidized acrylated vegetable oil is present in the oral care composition in an amount ranging from about 75 wt% to about 99.95 wt%, such as from about 95 wt% to about 99.95 wt%, based on the total weight of the oral care composition.

5. The oral care composition according to any one of the preceding claims, wherein the at least one photoinitiator is selected from alpha-diketones, such as camphorquinone and 1-phenyl- 1,2-propane dione; bisacyl phosphine oxides, such as bis(2,4,6-trimethylbenzoyl)- phenylphosphine oxide and 2,4,6-trimethylbenzoyl diphenylphosphine oxide; alphaaminoalkylphenones, such as 2-benzyl-2-dimethylamino-l-(4-morpholinophenyl)-butanone-l and 2-methyl-l-(4-methylthiophenyl)-2-morpholinopropane-l-one; and titanocenes, such as bisfr - 2,4-cyclopentadiene-l-yl)-bis(2,6-difluoro-3-(lH-pyrrole-l-yl)phenyl) titanium; benzoin methyl ether; 1 -hydroxy cyclohexylphenyl ketone; and combinations thereof.

6. The oral care composition according to claim 5, wherein the at least one photoinitiator is camphorquinone.

7. The oral care composition according to any one of the preceding claims, wherein the at least one photoinitiator is present in the oral care composition in an amount ranging from about 0.01 wt% to about 1 wt%, such as from about 0.2 wt% to about 0.8 wt%, about 0.4 wt% to about 0.6 wt%, or about 0.5 wt%, based on the total weight of the oral care composition.

8. The oral care composition according to any one of claims 1-4, wherein the at least one photoinitiator is water-soluble.

9. The oral care composition according to claim 8, wherein the at least one photoinitiator is selected from riboflavin, eosin, eosin Y, fluorescein, Rose Bengal, potassium persulfate, ammonium persulfate, sodium persulfate, and combinations thereof.

10. The oral care composition according to claim 9, wherein the at least one photoinitiator is riboflavin.

11. The oral care composition according to any of claims 8 to 10, wherein the at least one photoinitiator is present in the oral care composition in an amount ranging from about 0.001 wt% to about 0.1 wt%, such as about 0.002 wt% to about 0.008 wt%, about 0.004 wt % to about 0.006 wt%, or about 0.005 wt%, based on the total weight of the oral care composition.

12. The oral care composition according to any one of claims 8 to 11 , wherein the photoinitiator system further comprises at least one co-initiator.

13. The oral care composition according to claim 12, wherein the at least one co-initiator is L- arginine.

14. The oral care composition according to claim 11 or 12, wherein the at least one co-initiator is present in the oral care composition in an amount ranging from about 0.01 wt% to about 1 wt%, such as from about 0.1 wt% to about 0.8 wt%, about 0.4 wt% to about 0.6 wt%, or about 0.5 wt%.

15. The oral care composition according to any one of claims 8 to 14, further comprising water.

16. The oral care composition according to claim 15, wherein the water is present in the oral care composition in an amount ranging from about 1 wt% to about 10 wt%, such as from about 2 wt% to about 8 wt%, about 4 wt% to about 6 wt%, about 5 wt%, or about 4.995 wt%.

17. An oral care composition for reducing dental hypersensitivity consisting of: at least one epoxidized acrylated vegetable oil; and a photoinitiator system comprising at least one photoinitiator.

18. The oral care composition according to claim 17, wherein the at least one epoxidized acrylated vegetable oil is epoxidized acrylated soybean oil.

19. The oral care composition according to claim 17 or 18, wherein the photoinitiator system consists of camphorquinone.

20. The oral care composition according to claim 17 or 18, wherein the photoinitiator system consists of riboflavin, L-arginine, and water.

21. A method of reducing or preventing dental hypersensitivity in a subject in need thereof, the method comprising applying the oral care composition according to any claims 1 to 20 to a surface of the teeth of the subject.

22. The method according to claim 21, further comprising applying light to the surface of the teeth.

23. The method according to claim 22, wherein the light has a wavelength ranging from about 380 nm to about 500 nm, such as from about 400 nm to about 500 nm or about 440 nm to about 470 nm.

24. The method according to claim 22 or 23, wherein the light is applied to the surface of the teeth for at least about 15 seconds, such as at least about 30 seconds, at least about 45 seconds, or at least about one minute.

25. The method according to any one of claims 20 to 24, wherein the method occludes at least about 50% of exposed dentin tubules, such as at least about 75%, at least about 85%, or at least about 90% of exposed dentine tubules.

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