Patent Description:
Compositions containing fluoride are routinely applied to teeth to aid in the prevention and treatment of a number of dental problems. For example, individuals can apply dentifrices that include fluoride, such as mouthwashes and toothpastes, to their teeth to prevent tooth decay. In these situations, the fluoride may contact the teeth for a relatively limited amount of time, such as a few minutes.

In some cases, it can be desirable to apply fluoride to teeth for a prolonged period of time and to apply an amount of fluoride that is greater than the amount typically found in dentifrices available to consumers. For instance, the prevention and treatment of tooth hypersensitivity and dental caries can be enhanced when fluoride is applied to the teeth for time periods of about or greater than <NUM> hours. Often, dental varnishes can be used to deliver fluoride directly to the surface of teeth for prolonged periods of time.

Dental varnishes can be applied to teeth using a brush, probe, or other applicator. After the dental varnish dries and any solvents evaporate, a fluoride-containing film is formed on the surface of the teeth that remains on the teeth for a number of hours until the film is removed. In some cases, the dental varnish can be removed by mechanical means, such as the brushing of the teeth or chewing food.

The uniformity of the distribution of the fluoride on the teeth can affect the effectiveness of a dental varnish in the treatment and prevention of tooth problems. Some previous compositions of dental varnishes provide an uneven distribution of fluoride on teeth due to rheological properties of the compositions that cause a non-uniform distribution of fluoride in the dental varnish. In certain instances, the non-uniform distribution of fluoride in previous dental varnishes is caused by rheological properties that result in phase separation of the previous dental varnishes. The rheological properties of dental varnishes can be affected by properties of components of the dental varnishes. For example, in some cases, the properties of the components of the dental varnishes can vary, which results in inconsistent rheological properties of the dental varnish. Thus, the effectiveness of these previous compositions of dental varnishes can also be inconsistent.

<CIT> discloses hypersensitivity preventative tooth varnish compositions comprising, inter alia, ethyl cellulose and fluoride, and methods for the use of such compositions for the treatment of hypersensitive teeth. There is a need for a dental varnish formulation that provides uniform distribution of fluoride on the teeth.

Unless otherwise indicated, the terms "%" or "percent" when used in connection with an ingredient of the dental varnish compositions is intended to refer to the percent by wet weight of the indicated ingredient in the dental varnish composition.

The dental varnish composition of the invention is defined in the claims and includes a fluoride source, such as sodium fluoride. The dental varnish composition also includes a non-aqueous solvent, that is ethanol as defined in the claims. In addition, the dental varnish composition includes ethyl cellulose in an amount of from <NUM>% to <NUM>% by wet weight in the dental varnish composition, which is effective to achieve suspension of the fluoride source. For example, the dental varnish composition can include ethyl cellulose in an amount from from <NUM>% to <NUM>%, or from <NUM>% to <NUM>% by wet weight in the dental varnish composition. Further, the dental varnish composition includes one or more resins selected from mastic, colophonium, or a combination thereof. In some cases, the dental varnish composition can have a high shear viscosity that is at least <NUM>,<NUM> centipoise (cps). In an additional example, the dental varnish composition can have a high shear viscosity from <NUM>,<NUM> cps to <NUM>,<NUM> cps.

The non-aqueous solvent that is ethanol can be present in an amount from <NUM>% to <NUM>%. The dental varnish composition can also include a fluoride source present in an amount from <NUM>% to <NUM>%. The ethyl cellulose can have a viscosity no greater than <NUM> centipoise (cps). The mastic can be present in an amount from <NUM>% to <NUM>% and the colophonium can be present in an amount from <NUM>% to <NUM>%.

A process for preparing the compositions can include combining a first portion of an amount of an ethanol solution and a first portion of an amount of colophonium to form an ethanol solution and colophonium mixture. The process can also include combining the ethanol solution and colophonium mixture with a fluoride source to form a first dental varnish component. Additionally, the process can include combining a second portion of the amount of the ethanol solution, a second portion of the amount of the colophonium, a mastic, and an ethyl cellulose to form a second dental varnish component. Further, the process can include combining the first dental varnish component, the second dental varnish component, and a remainder of the amount of the ethanol solution to produce a composition of a dental varnish.

The invention is directed to dental varnish composition as defined in the claims. The compositions described herein have rheological properties that can decrease or eliminate instances of phase separation in dental varnishes. In particular, the compositions of dental varnishes described herein can include components that provide consistent rheological properties that cause a substantially uniform distribution of fluoride throughout the dental varnish. Accordingly, when the dental varnish is applied to teeth, the fluoride is distributed evenly on the teeth and provides effective treatment and/or prevention of dental problems. Finally, the dental varnish of the present disclosure provides an improved appearance on the tooth surface.

The compositions of dental varnish include ethyl cellulose to provide rheological properties of the dental varnish that minimize or eliminate phase separation of the dental varnish. The rheological properties of dental varnish compositions that include ethyl cellulose can also provide a substantially uniform distribution of fluoride in the dental varnish. In some cases, the ethyl cellulose can be a replacement for shellacs that have been included in previous compositions of dental varnishes. The use of a synthetic component in dental varnishes, such as ethyl cellulose, in lieu of a natural component, such as shellac, can provide improved control over rheological properties. In particular, the ethyl cellulose can provide rheological properties of dental varnishes that are improved over compositions of dental varnishes that include a shellac or a shellac-containing wax. For example, the instances of phase separation for the dental varnish can decrease when ethyl cellulose is used in compositions of dental varnishes as opposed to a shellac or a shellac-containing wax. Furthermore, the adhesive properties of the dental varnish compositions including ethyl cellulose and the suspension of fluoride in the dental varnish compositions are at least comparable to the previous dental varnishes that include shellac and/or a wax containing shellac.

Ethyl cellulose is an ether derivative of cellulose. Cellulose is a natural polysaccharide made up of long chains of β-anhydroglucose units joined together by acetal linkages. Each anhydroglucose unit has three hydroxyl groups, which may form ethyl ethers, e.g., by the reaction of ethyl chloride with alkali cellulose, thus providing ethyl cellulose. The degree of ethoxylation varies in different ethyl cellulose products. Complete substitution of all three groups on the anhydroglucose units would give the triethyl ether possessing a substitution value of <NUM>, or <NUM>% ethoxyl. The completely substituted triethylcellulose, however, lacks strength and flexibility, is not thermoplastic, and exhibits limited compatibility and solubility. The degree of substitution, as well as the molecular weight, affects the viscosity and solubility of the product. In certain embodiments, the ethyl cellulose has an average substitution value of between <NUM> and <NUM> ethoxyl groups per anhydroglucose unit, or <NUM>% to <NUM>% ethoxyl content. In some cases, the ethyl cellulose has an average substitution value of <NUM>-<NUM> ethoxyl groups per anhydroglucose unit, corresponding to an ethoxyl content of <NUM>% to <NUM>%.

In an embodiment, compositions of dental varnishes can include at least <NUM> % ethyl cellulose, at least <NUM>% ethyl cellulose, at least <NUM>% ethyl cellulose, or at least <NUM>% ethyl cellulose. Additionally, compositions of dental varnishes can include no greater than <NUM>% ethyl cellulose, no greater than <NUM>% ethyl cellulose, no greater than <NUM>% ethyl cellulose, or no greater than <NUM>% ethyl cellulose. In an illustrative example, compositions of dental varnishes can include from <NUM>% to <NUM>% ethyl cellulose. In an additional illustrative example, compositions of dental varnishes can include from <NUM>% to <NUM>% ethyl cellulose. In other illustrative examples, compositions of dental varnishes can include from <NUM>% to <NUM>% ethyl cellulose, from <NUM>% to <NUM>% ethyl cellulose, from <NUM>% to <NUM>% ethyl cellulose, or from <NUM>% to <NUM>% ethyl cellulose.

Ethyl cellulose included in compositions of dental varnishes can have a viscosity of at least <NUM> centipoise (cps) but no greater than <NUM> cps. Furthermore, unless noted otherwise, "viscosity" as used herein refers to dynamic viscosity, sometimes referred to as shear viscosity.

In a particular example, ethyl cellulose included in compositions of dental varnishes can have a viscosity of at least <NUM> cps, at least <NUM> cps, or at least <NUM> cps, but no greater than <NUM> cps. In addition, ethyl cellulose included in compositions of dental varnishes can have a viscosity no greater than <NUM> cps, no greater than <NUM> cps, no greater than <NUM> cps, or no greater than <NUM> cps. In an illustrative example, ethyl cellulose included in compositions of dental varnishes can have a viscosity from <NUM> cps to <NUM> cps, from <NUM> cps to <NUM> cps, from <NUM> cps to <NUM> cps, or from <NUM> cps to <NUM> cps.

In other cases, ethyl cellulose included in compositions of dental varnishes can have a viscosity of at least <NUM> cps, at least <NUM> cps, at least <NUM> cps, or at least <NUM> cps, but no greater than <NUM> cps. Further, ethyl cellulose included in compositions of dental varnishes can have a viscosity that is no greater than <NUM> cps, no greater than <NUM> cps, no greater than <NUM> cps, no greater than <NUM> cps, or no greater than <NUM> cps. In an illustrative example, ethyl cellulose included in compositions of dental varnishes can have a viscosity from <NUM> cps to <NUM> cps, from <NUM> cps to <NUM> cps, from <NUM> cps to <NUM> cps, or from <NUM> cps to <NUM> cps.

Also, ethyl cellulose included in compositions of dental varnishes can have a viscosity of at least <NUM> cps, at least <NUM> cps, at least <NUM> cps, at least <NUM> cps, but no greater than <NUM> cps. In an illustrative example, ethyl cellulose included in compositions of dental varnishes can have a viscosity from <NUM> cps to <NUM> cps, from <NUM> cps to <NUM> cps, from <NUM> cps to <NUM> cps, or from <NUM> cps to <NUM> cps.

In some instances, the amount of ethyl cellulose included in dental varnish compositions can be related to a viscosity of the ethyl cellulose included in the dental varnish. For example, an ethyl cellulose having a viscosity from <NUM> cps to <NUM> cps can be present in compositions of dental varnishes in an amount from <NUM>% to <NUM>% or from <NUM>% to <NUM>%. In another example, an ethyl cellulose having a viscosity from <NUM> cps to <NUM> cps can be present in compositions of dental varnishes in amount from <NUM>% to <NUM>% or from <NUM>% to <NUM>%. In an additional example, an ethyl cellulose having a viscosity of <NUM> cps can be present in compositions of dental varnishes in an amount from <NUM>% to <NUM>% for from <NUM>% to <NUM>%.

The viscosity of the ethyl cellulose included in compositions of dental varnishes is measured according to the ASTM D <NUM> standard as of the time of filing this application using <NUM>% by weight ethyl cellulose in a solution of an <NUM>:<NUM> toluene ethanol mixture by weight on a sample dried <NUM> minutes at <NUM>.

Dental varnish compositions include a non-aqueous solvent that is ethanol as defined in the claims. Generally, compositions of dental varnishes can include ethanol, ethyl acetate, or combinations thereof. In a particular example, compositions of dental varnishes can include at least <NUM>% of a non-aqueous solvent, at least <NUM>% of the non-aqueous solvent, at least <NUM>% of the non-aqueous solvent, or at least <NUM>% of the non-aqueous solvent. Additionally, compositions of dental varnishes can include no greater than <NUM>% of the non-aqueous solvent, no greater than <NUM>% of the non-aqueous solvent, no greater than <NUM>% of the non-aqueous solvent, or no greater than <NUM>% of the non-aqueous solvent. In illustrative examples, compositions of dental varnishes can include from <NUM>% to <NUM>% of the non-aqueous solvent, from <NUM>% to <NUM>% of the non-aqueous solvent, from <NUM>% to <NUM>% of the non-aqueous solvent, from <NUM>% to <NUM>% of the non-aqueous solvent, or from <NUM>% to <NUM>% of the non-aqueous solvent.

In some cases, dental varnishes can include the non-aqueous solvent that is ethanol derived from an ethanol solution, such as a <NUM>% ethanol solution having a balance of other components including water. Compositions of dental varnishes can have no greater than <NUM>% water, no greater than <NUM>% water, or be substantially free of water. As used herein, the term "substantially free" with respect to a material is meant to indicate that the substance includes at most trace amounts of the material.

Compositions of dental varnishes include one or more resins. As used herein, the term "resin" can refer to a natural resin that is secreted or extracted from a plant or tree and/or a synthetic resin including an artificial polymer base. The one or more resins included in compositions of dental varnishes include natural resins which are mastic, colophonium, or both. Mastic can include a resin obtained from the mastic tree (Pistacia lentiscus) and colophonium can include a resin derived from the stumps or sap of various plants, e.g. certain pine and conifer species.

A total amount of one or more resins included in dental varnish compositions can be at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, or at least <NUM>%. Also, a total amount of one or more resins included in dental varnish compositions can be no greater than <NUM>%, no greater than <NUM>%, no greater than <NUM>%, no greater than <NUM>%, no greater than <NUM>%, or no greater than <NUM>%. In an illustrative example, a total amount of one or more resins included in compositions of dental varnishes can be from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, or from <NUM>% to <NUM>%.

In particular implementations, compositions of dental varnishes can include at least <NUM>% of a first resin, at least <NUM>% of the first resin, at least <NUM>% of the first resin, or at least <NUM>% of the first resin. Further, compositions of dental varnishes can include no greater than <NUM>% of the first resin, no greater than <NUM>% of the first resin, no greater than <NUM>% of the first resin, or no greater than <NUM>% of the first resin. In illustrative examples, compositions of dental varnishes can include from <NUM>% to <NUM>% of the first resin, from <NUM>% to <NUM>% of the first resin, from <NUM>% of the first resin to <NUM>% of the first resin, or from <NUM>% of the first resin to <NUM>% c of the first resin. The first resin can include colophonium. The colophonium included in compositions of dental varnishes can be compendial grade colophonium.

Additionally, compositions of dental varnishes can include at least <NUM>% of a second resin, at least <NUM>% of the second resin, at least <NUM>% of the second resin, or at least <NUM>% of the second resin. Compositions of dental varnishes can also include no greater than <NUM>% of the second resin, no greater than <NUM>% of the second resin, no greater than <NUM>% of the second resin, or no greater than <NUM>% of the second resin. In illustrative examples, compositions of dental varnishes can include from <NUM>% to <NUM>% of the second resin, from <NUM>% to <NUM>% of the second resin, from <NUM>% to <NUM>% of the second resin, or from <NUM>% to <NUM>% of the second resin. The second resin can include a mastic. The mastic included in compositions of dental varnishes can be compendial grade mastic.

In situations where compositions of dental varnishes include colophonium and a mastic, the dental varnish compositions can include from <NUM>% to <NUM>% colophonium and from <NUM>% to <NUM>% mastic. In an additional example, dental varnish compositions can include <NUM>% to <NUM>% colophonium and from <NUM>% to <NUM>% mastic. In another example, dental varnish compositions can include from <NUM>% to <NUM>% colophonium and from <NUM>% to <NUM>% mastic.

Compositions of dental varnishes include a fluoride source. The fluoride source can include a fluorine-containing compound that has a beneficial effect on the care and hygiene of the teeth, e.g. diminution of enamel solubility in acid and protection of the teeth against decay. The fluoride source can include soluble salts of a fluorine anion; such as, for example: sodium fluoride, potassium fluoride, calcium fluoride, zinc fluoride, zinc ammonium fluoride, lithium fluoride, ammonium fluoride, stannous fluoride, stannous fluorozirconate. The fluoride source can also include complex fluorides, monofluorophosphates and salts thereof such as, for example, sodium monofluorophosphate, potassium monofluorophosphate, laurylamine hydrofluoride, diethylaminoethyloctoylamide hydrofluoride, didecyldimethylammonium fluoride, cetylpyridinium fluoride, dilaurylmorpholinium fluoride, sarcosine stannous fluoride, glycine potassium fluoride, glycine hydrofluoride, and amine fluorides.

The fluoride source can be present in compositions of dental varnishes in an amount of at least <NUM>,<NUM> parts per million (ppm), at least <NUM>,<NUM> ppm, at least <NUM>,<NUM> ppm, at least <NUM>,<NUM> ppm, at least <NUM>,<NUM> ppm, or at least <NUM>,<NUM> ppm. Additionally, the fluoride source can be present in compositions of dental varnishes in an amount no greater than <NUM>,<NUM> ppm, no greater than <NUM>,<NUM> ppm, no greater than <NUM>,<NUM> ppm, or no greater than <NUM>,<NUM> ppm. In an illustrative example, compositions of dental varnishes can include <NUM>,<NUM> ppm to <NUM>,<NUM> ppm of a fluoride source, <NUM>,<NUM> ppm to <NUM>,<NUM> ppm of a fluoride source, <NUM>,<NUM> ppm to <NUM>,<NUM> ppm of a fluoride source, or <NUM>,<NUM> ppm to <NUM>,<NUM> ppm of a fluoride source.

In order to provide a concentration of the fluoride source in a specified ppm range, the exact weight percentage of the fluoride source in the compositions may vary, depending upon the stoichiometric properties of different fluoride sources. In some cases, compositions of dental varnishes can include at least <NUM>% of a fluoride source, at least <NUM>% of a fluoride source, at least <NUM>% of a fluoride source, or at least <NUM>% of a fluoride source. Further, compositions of dental varnishes can include no greater than <NUM>% of a fluoride source, no greater than <NUM>% of a fluoride source, no greater than <NUM>% of a fluoride source, or no greater than <NUM>% of a fluorides source. In an illustrative example, compositions of dental varnishes can include from <NUM>% to <NUM>% of a fluoride source, from <NUM>% to <NUM>% of a fluoride source, or from <NUM>% to <NUM>% of a fluoride source. The amount of the fluoride source included in compositions of dental varnishes can be at least the amount of ethyl cellulose in the compositions of dental varnishes. Alternatively, the amount of the fluoride source included in compositions of dental varnishes can be less than the amount of ethyl cellulose in the compositions of dental varnishes. In a particular implementation, the fluoride source is sodium fluoride.

Compositions of dental varnishes can include one or more additional components, such as one or more waxes, one or more flavoring components, one or more sweetener components, one or more coloring components, or combinations thereof. The one or more sweetener components can include sucrose, lactose, maltose, xylitol, sodium cyclamate, perillartine, AMP (aspartyl phenyl alanine methyl ester), saccharin, combinations thereof, and the like. The one or more flavoring components can include flavoring oils, such as oil of spearmint, oil of peppermint, oil of wintergreen, oil of clove, oil of sage, oil of eucalyptus, oil of marjoram, oil of cinnamon, oil of lemon, oil of raspberry, oil of orange, combinations thereof, and the like.

Dental varnish compositions can include a wax in an amount of at least <NUM>%, at least <NUM>%, or at least <NUM>%. In addition, the compositions of dental varnish can also include a wax present in amount of no greater than <NUM>%, no greater than <NUM>%, or no greater than <NUM>%. In an illustrative example, the compositions of dental varnish can include wax present in an amount from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, or from <NUM>% to <NUM>%. In some cases, the wax can include a beeswax, such as white beeswax. The white beeswax can be United States Pharmaceutical (USP) grade. Additionally, the compositions of dental varnishes may be free from a wax including shellac.

Further, compositions of dental varnishes can include no greater than <NUM>% of one or more sweetener components, no greater than <NUM>% of one or more sweetener components, or no greater than <NUM>% of one or more sweetener components. In an illustrative example, the compositions of dental varnishes can include from <NUM>% to <NUM>% of one or more sweetener components. In some cases, a sweetener component can include a saccharin, such as saccharin <NUM>. Compositions of dental varnishes can include no greater than <NUM>% of one or more flavoring components, no greater than <NUM>% of one or more flavoring components, or no greater than <NUM>% of one or more flavoring components. In another illustrative example, the compositions of dental varnishes can include from <NUM>% to <NUM>% of one or more flavoring components.

Other materials may be incorporated in the compositions of dental varnishes, such as whitening agents (e.g., urea peroxide, calcium peroxide, titanium dioxide, hydrogen peroxide, complexes of polyvinylpyrrolidone (PVP) and hydrogen peroxide), preservatives, vitamins (e.g., vitamin B6, vitamin B12, vitamin E, vitamin K), silicones, chlorophyll compounds, potassium salts (e.g., potassium nitrate) for the treatment of dental hypersensitivity, anti-tartar agents (e.g., sodium tripolyphosphate and di- and tetraalkali metal pyrophosphate salts such as di- and tetrasodium pyrophosphate), calcium-based salts (e.g., dicalcium phosphate, tricalcium phosphate, precipitated calcium carbonate to be used alone or in combination with amino acids such as L-arginine), or combinations thereof. These additional materials can be present in compositions of dental varnishes in amounts that do not adversely affect the rheological properties of the dental varnishes and/or the effectiveness of the dental varnishes in the treatment or prevention of tooth problems, such as amounts no greater than <NUM>%, no greater than <NUM>%, no greater than <NUM>%, no greater than <NUM>%, or no greater than <NUM>%.

In one embodiment, the dental varnish according to the invention can have a high shear viscosity of at least <NUM> cps, at least <NUM> cps, at least <NUM> cps, at least <NUM>,<NUM> cps, at least <NUM>,<NUM> cps, at least <NUM>,<NUM> cps, at least <NUM>,<NUM> cps, at least <NUM>,<NUM> cps, or at least <NUM>,<NUM> cps, and can have a high shear viscosity of no greater than <NUM>,<NUM> cps, no greater than <NUM>,<NUM> cps, no greater than <NUM>,<NUM> cps, no greater than <NUM>,<NUM> cps, no greater than <NUM>,<NUM> cps, or no greater than <NUM>,<NUM> cps. In an illustrative example, compositions of dental varnish according to the invention can have a high shear viscosity from <NUM> cps to <NUM>,<NUM> cps, from <NUM>,<NUM> cps to <NUM>,<NUM> cps, from <NUM>,<NUM> cps to <NUM>,<NUM> cps, or from <NUM>,<NUM> cps to <NUM>,<NUM> cps. In some cases, compositions of dental varnish according to the invention can have a high shear viscosity from <NUM>,<NUM> cps to <NUM>,<NUM> cps.

The high shear viscosity can be measured using a HA, RV, or LV Brookfield DV* series or DV*T series viscometer having a v72, v73, or v74 spindle at a shear rate of <NUM> rotation per minute (RPM). The majority of data points measured can be measured between <NUM>% torque and <NUM>% torque.

Furthermore, compositions of dental varnishes can have a yield stress as the shear rate is ramping up from <NUM> Pascals (Pa) to <NUM> Pa, from <NUM> Pa to <NUM> Pa, from <NUM> Pa to <NUM> Pa, from <NUM> Pa to <NUM> Pa, or from <NUM> Pa to <NUM> Pa. Also, compositions of dental varnishes can have a yield stress as the shear rate is ramping down from <NUM> Pa to <NUM> Pa, from <NUM> Pa to <NUM> Pa, from <NUM> Pa to <NUM> Pa, or from <NUM> Pa to <NUM> Pa. Compositions of dental varnishes can have a ratio of yield stress when a shear rate is ramping up to a yield stress when a shear rate is ramping down of at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, or at least <NUM>. The ratio of yield stress when a shear rate is ramping up to yield stress when a shear rate is ramping down can be no greater than <NUM>, no greater than <NUM>, no greater than <NUM>, or no greater than <NUM>. In an illustrative example, the ratio of yield stress when a shear rate is ramping up to yield stress when a shear rate is ramping down can be between <NUM> and <NUM>. In another illustrative example, the ratio of yield stress when a shear rate is ramping up to yield stress when a shear rate is ramping down can be between <NUM> and <NUM>. In a further illustrative example the ratio of yield stress when a shear rate is ramping up to yield stress when a shear rate is ramping down can be between <NUM> and <NUM>.

The yield stress can be measured using a HA, RV, or LV Brookfield DV* series or Brookfield DV*T series viscometer having a v72, v73, or v74 spindle with a minimum shear rate of <NUM> RPM and a maximum shear rate of <NUM> RPM.

Compositions of dental varnishes according to embodiments described herein can have a release of fluoride of <NUM> to <NUM> per g of dental varnish after <NUM> hours or a release of fluoride of <NUM> to <NUM> per g of dental varnish after <NUM> hours. In addition, compositions of dental varnishes can have a release of fluoride of <NUM> to <NUM> per g of dental varnish after <NUM> hours or a release of fluoride of <NUM> to <NUM> per g of dental varnish after <NUM> hours. The release of fluoride can be measured based on dental varnishes placed on bovine enamel.

Furthermore, dental varnishes can have an uptake of fluoride on bovine enamel of <NUM> ppm to <NUM> ppm or <NUM> ppm to <NUM> ppm. The fluoride uptake can be measured according to test method <NUM> of the Food and Drug Administration (FDA) Monograph or a variation of the test method <NUM> of the FDA Monograph.

Also, dental varnishes can have a retention from <NUM>% to <NUM>% on bovine enamel after <NUM> hour or a retention from <NUM>% to <NUM>% on bovine enamel after <NUM> hour. In some instances, dental varnishes can have a retention after <NUM> hours from <NUM>% to <NUM>% on bovine enamel or from <NUM>% to <NUM>% on bovine enamel. Additionally, dental varnishes described herein can have a retention after <NUM> hours from <NUM>% to <NUM>% on bovine enamel or a retention after <NUM> hours from <NUM>% to <NUM>% on bovine enamel.

In some cases, when dental varnishes having compositions described herein are applied to tooth enamel, the dental varnishes can be free of color and appear to be clear. That is, very little, if any, light is absorbed by the dental varnish. In this way, the compositions of dental varnishes described herein differ from some previous compositions because the previous compositions have a yellow color. That is, the previous compositions of dental varnishes absorb wavelengths of electromagnetic radiation from <NUM> to <NUM>.

In a particular illustrative example, compositions of dental varnishes can have from <NUM>% to <NUM>% colophonium, from <NUM>% to <NUM>% ethanol, from <NUM>% to <NUM>% mastic, from <NUM>% to <NUM>% sodium fluoride, and from <NUM>% to <NUM>% ethyl cellulose. In these compositions, the viscosity of the ethyl cellulose can be from <NUM> cps to <NUM> cps. Additionally, these compositions can include from <NUM>% to <NUM>% white beeswax, from <NUM>% to <NUM>% saccharin <NUM>, and from <NUM>% to <NUM>% of a flavoring component (such as Raspberry Flavor). Furthermore, these compositions of dental varnishes can have a viscosity from <NUM>,<NUM> cps to <NUM>,<NUM> cps and a ratio of yield stress as the shear rate is ramping up to yield stress when a shear rate is ramping down from <NUM> to <NUM>.

In another particular illustrative example, compositions of dental varnishes can have from <NUM>% to <NUM>% colophonium, from <NUM>% to <NUM>% ethanol, from <NUM>% to <NUM>% mastic, from <NUM>% to <NUM>% sodium fluoride, and from <NUM>% to <NUM>% ethyl cellulose. In these compositions, the viscosity of the ethyl cellulose can be from <NUM> cps to <NUM> cps. Additionally, these compositions can include from <NUM>% to <NUM>% white beeswax, from <NUM>% to <NUM>% saccharin <NUM>, and from <NUM>% to <NUM>% of a flavoring component (such as Raspberry Flavor). Furthermore, these compositions of dental varnishes can have a viscosity from <NUM>,<NUM> cps to <NUM>,<NUM> cps and a ratio of yield stress as the shear rate is ramping up to yield stress when a shear rate is ramping down from <NUM> to <NUM>.

In a further particular illustrative example, compositions of dental varnishes can have from <NUM>% to <NUM>% colophonium, from <NUM>% to <NUM>% ethanol, from <NUM>% to <NUM>% mastic, from <NUM>% to <NUM>% sodium fluoride, and from <NUM>% to <NUM>% ethyl cellulose. In these compositions, the viscosity of the ethyl cellulose can be from <NUM> cps to <NUM> cps. Additionally, these compositions can include from <NUM>% to <NUM>% white beeswax, from <NUM>% to <NUM>% saccharin <NUM>, and from <NUM>% to <NUM>% of a flavoring component (such as Raspberry Flavor). Furthermore, these compositions of dental varnishes can have a viscosity from <NUM>,<NUM> cps to <NUM>,<NUM> cps and a ratio of yield stress as the shear rate is ramping up to yield stress when a shear rate is ramping down from <NUM> to <NUM>.

The compositions of dental varnishes described herein can be utilized in the prevention and/or treatment of dental problems. For example, compositions of dental varnishes can be used to prevent and/or treat tooth hypersensitivity in humans, domesticated animals, or both. As used herein, the term "domesticated animal" includes animals generally recognized to be pets, for example dogs and cats. In another example, the compositions of dental varnishes can be used to prevent dental carries in humans, domesticated animals, or both. In an illustrative example, a method of prevention and/or treatment of dental problems can include applying a composition of a dental varnish to the surface of one or more teeth. The dental varnish composition can be applied using a brush, spray, or another applicator. In some cases, an amount of dental varnish applied to the one or more teeth can be from <NUM> to <NUM> grams, from <NUM> to <NUM>, or from <NUM> to <NUM>. In an illustrative example, at least <NUM> of a dental varnish composition can be applied to the one or more teeth. In addition, the compositions of dental varnishes can be in contact with the one or more teeth for a duration of at least <NUM> hour, at least <NUM> hours, at least <NUM> hours, at least <NUM> hours, at least <NUM> hours or at least <NUM> hours. Furthermore, the compositions of dental varnishes can be in contact with the one or more teeth for a duration no greater than <NUM> hours, no greater than <NUM> hours, no greater than <NUM> hours, or no greater than <NUM> hours. In some instances, the compositions of dental varnishes can be in contact with the one or more teeth for a duration from <NUM> minutes to <NUM> hours, from <NUM> hour to <NUM> hours, or from <NUM> hours to <NUM> hours.

An example process to make a dental varnish according to embodiments described herein includes combining a first portion of an amount of ethanol solution and a first portion of an amount of colophonium. In some cases, the ethanol solution can be a <NUM>% ethanol solution. In addition, the first portion of the amount of ethanol solution and the first portion of the amount of colophonium can be mixed for a period of time sufficient to disperse the colophonium in the ethanol solution. The mixing can take place via mechanical means. Further, the first portion of the ethanol solution and the first portion of the colophonium solution can be covered while being mixed.

An amount of ethanol solution can include from <NUM>% to <NUM>% by weight of a total weight of the ethanol solution and colophonium mixture and an amount of the colophonium can include from <NUM>% to <NUM>% by weight of a total weight of the ethanol solution and colophonium mixture. Additionally, an amount of ethanol solution can include from <NUM>% to <NUM>% by weight of a total weight of the ethanol solution and colophonium mixture and an amount of the colophonium can include from <NUM>% to <NUM>% by weight of a total weigh of the ethanol solution and colophonium mixture.

Additionally, the ethanol solution and colophonium mixture can be combined with a fluoride source to form a first dental varnish component. For example, the ethanol solution and colophonium mixture can be combined with sodium fluoride. In particular, the ethanol solution and colophonium mixture can be mixed with the fluoride source for a specified duration, such as from <NUM> minutes to <NUM> minutes, from <NUM> minutes to <NUM> minutes, or from <NUM> minutes to <NUM> minutes. Additionally, the colophonium/ethanol solution mixture and the fluoride source can be covered while being mixed. In some cases, the first dental varnish component is to be set aside for a period of time before being used again during the process <NUM>, such as from <NUM> minutes to <NUM> minutes, from <NUM> minutes to <NUM> minutes, or from <NUM> minutes to <NUM> minutes.

The first dental varnish component can include an amount of the ethanol solution and colophonium mixture from <NUM>% to <NUM>% by weight of a total weight of the first dental varnish component and an amount of the fluoride source can include from <NUM>% to <NUM>% by weight of a total weight of the first dental varnish component. Further, the first dental varnish component can include an amount of the ethanol solution and colophonium mixture from <NUM>% to <NUM>% by weight of a total weight of the first dental varnish component and an amount of the fluoride source can include from <NUM>% to <NUM>% by weight of a total weight of the first dental varnish component.

Furthermore, a second portion of the amount of the ethanol, a second portion of the amount of the colophonium, mastic, and ethyl cellulose can be combined to form a second dental varnish component. In one example, the ethyl cellulose can have a viscosity from <NUM> cps to <NUM> cps. In another example, the ethyl cellulose can have a viscosity from <NUM> cps to <NUM> cpsThe second portion of the amount of the ethanol, the second portion of the amount of the colophonium, the mastic, and the ethyl cellulose can be mixed for a duration, such as from <NUM> hour to <NUM> hours, from <NUM> hours to <NUM> hours, or from <NUM> hours to <NUM> hours. Additionally, the second portion of the amount of the ethanol, the second portion of the amount of the colophonium, the mastic, and the ethyl cellulose can be mixed at a temperature from <NUM> to <NUM>, from <NUM> to <NUM>, or from <NUM> to <NUM>. In some cases, the second portion of the amount of the ethanol, the second portion of the amount of the colophonium, the mastic, and the ethyl cellulose can be mixed under reflux. Optionally, an additional amount of the ethanol solution can be added after mixing the second portion of the amount of the ethanol solution, the second portion of the amount of the colophonium, the mastic, and the ethyl cellulose.

The second dental varnish component can include a second portion of the amount of ethanol from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component or the second dental varnish component can include a second portion of the amount of ethanol from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component. In addition, the second dental varnish component can include a second portion of the amount of colophonium from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component or the second dental varnish component can include a second portion of the amount of colophonium from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component. Further, the second dental varnish component can include mastic from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component or the second dental varnish component can include mastic from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component. Also, the second dental varnish component can include ethyl cellulose from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component, from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component, from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish, or from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component. The second dental varnish component can also include wax, such as a white wax, from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component. Additionally, the second dental varnish component can include a sweetener component, such as saccharin, from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component. In an illustrative example, the second dental varnish component can include the second portion of the amount of ethanol from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component, the second amount of the colophonium from <NUM>% to <NUM>% by weight of a total weight of the second dental varnish component, mastic from <NUM>% to <NUM>% by weight of a total weight of the second varnish component, ethyl cellulose from <NUM>% to <NUM>% by weight of a total weight of the second varnish component, white wax from <NUM>% to <NUM>% by weight of a total weight of the second varnish component, and saccharin from <NUM> % to <NUM> % by weight of a total weight of the second varnish component.

Also, the first dental varnish component, the second dental varnish component, and a remainder of the amount of ethanol can be combined to produce a composition of a dental varnish. In some cases, the second dental varnish component can be cooled to a temperature from <NUM> to <NUM>, from <NUM> to <NUM>, or from <NUM> to <NUM> before being combined with the first dental varnish component. The first dental varnish component and the second dental varnish component can be mixed for a duration, such as <NUM> minutes to <NUM> minutes, from <NUM> minutes to <NUM> minutes, or from <NUM> minutes to <NUM> minutes. In some cases, a flavoring component can be added after the temperature of the mixture of the first dental varnish component and the second dental varnish component has cooled further to a temperature from <NUM> to <NUM>, from <NUM> to <NUM> or from <NUM> to <NUM>. Additionally, after the flavoring component has been added, mixing can take place for an additional duration, such as from <NUM> minutes to <NUM> minutes, from <NUM> minutes to <NUM> minutes, or from <NUM> minutes to <NUM> minutes.

The composition of dental varnish can include the first dental varnish component from <NUM>% to <NUM>% by weight of a total weight of the composition of dental varnish or from <NUM>% to <NUM>% by weight of a total weight of the composition of dental varnish. Additionally, the composition of dental varnish can include the second dental varnish component from <NUM>% to <NUM>% by weight of a total weight of the composition of dental varnish or from <NUM>% to <NUM>% by weight of a total weight of the composition of dental varnish. Further, the composition of dental varnish can include a flavoring component from <NUM>% to <NUM> % by weight of a total weight of the composition of dental varnish. Also, the composition of dental varnish can include a remainder of ethanol from <NUM>% to <NUM>% by weight of a total weight of the composition of dental varnish. In an illustrative example, the composition of dental varnish can include the first dental varnish component from <NUM>% to <NUM>% by weight of a total weight of the composition of the dental varnish, the second dental varnish component from <NUM>% to <NUM>% by weigh of a total weight of the composition of dental varnish, the flavoring component from <NUM>% to <NUM>% by weight of a total weight of the composition of dental varnish, and a remainder of the ethanol from <NUM>% to <NUM>% by weight of a total weight of the composition of dental varnish.

The compositions of dental varnishes described herein include ethyl cellulose at relatively low concentrations along with a colophonium/mastic based film forming component to effectively suspend a fluoride-containing source (e.g., sodium fluoride) in the dental varnishes. The use of the synthetic ethyl cellulose in place of naturally occurring tooth varnish suspending components (such as shellac and shellac wax), provides increased consistency of the dental varnish compositions, which in turn, can provide more effective treatment of dental problems. In particular, the fluoride source can be more uniformly distributed on the teeth that are contacted by the dental varnish compositions. Furthermore, the dental varnish compositions described herein minimize or eliminate phase separation and/or precipitation of the fluoride source. The film-forming properties of ethyl cellulose result in ease of application and retention to surfaces of teeth.

It is unexpected that the compositions of dental varnishes described herein provide rheological properties that achieve the substantially uniform suspension of a fluoride source without phase separation. In particular, the ethyl cellulose included in formulations described herein has viscosities that are less than those of previous compositions, which one of skill in the art would expect to cause a decrease in the viscosity of the overall dental varnish formulations. However, the lower viscosity ethyl cellulose included in the dental varnish formulations described herein provides a higher viscosity composition than previous dental varnish compositions. Thus, the rheological properties of the dental varnish formulations described herein are improved over the rheological properties of previous dental varnish formulations. The improved rheological properties result in a substantially uniform distribution of a fluoride source in the dental varnish formulations described herein, which causes the fluoride source to be more evenly distributed on the surface of teeth than previous dental varnish formulations. Accordingly, the effectiveness of the treatment and/or prevention of dental problems is also improved with respect to previous dental varnish formulations. In addition, the compositions of dental varnishes described herein can be thixotropic, and thus more easily spread during application. Such relatively high viscosity and thixotropic characteristics reduce and/or prevent the tendency of the compositions of dental varnishes described herein to run or drip upon application to tooth surfaces.

As will be evident to one of skill in the art, some components of the compositions of dental varnishes described herein may perform multiple functions, and the identification of a compound as having one function herein is not meant to exclude its use for other functions in a particular composition. Further, it is also understood that compounds in compositions of dental varnishes described herein may naturally react, disassociate, and/or form complexes with one another. Accordingly, certain components may be formed in situ, and also may in composition exist in different forms (for example, to the extent the sodium fluoride is dissolved, it will naturally disassociate into separate sodium and fluoride ions, as opposed to a solid salt).

The following examples are further illustrative of the compositions of dental varnishes described herein, but it is understood that the compositions of dental varnishes are not limited thereto. All amounts and proportions referred to herein and in the appended claims are by weight, unless otherwise indicated.

The dynamic viscosity of compositions of dental varnishes was measured over a range of shear stresses. Table <NUM> shows the compositions tested. The commercial composition is a previous dental varnish composition that includes shellac. Composition <NUM> was a dental varnish composition that includes <NUM> % of Aqualon®N-<NUM> ethyl cellulose from Hercules Corp. Composition <NUM> was a dental varnish composition according to an embodiment described herein that includes <NUM> % of Aqualon®N-<NUM> ethyl cellulose from Hercules Corp. Composition <NUM> was a dental varnish composition according to an embodiment described herein that includes a <NUM> % of Aqualon® N-<NUM> ethyl cellulose from Hercules Corp. The viscosity was measured using a Brookfield viscometer having a v74 spindle at a shear rate of <NUM> rotation per minute (RPM). The majority of data points measured were between <NUM>% torque and <NUM>% torque. FitFlowYS software was used to calculate the viscosity with fitting parameters of n=<NUM>, rate range of <NUM> to <NUM>, yield stress in Pascals from <NUM> to <NUM> and high shear viscosity in Pascal seconds from <NUM> to <NUM>. The yield stress was also measured using a Brookfield viscometer having a v74 spindle with a minimum shear rate of <NUM> RPM and a maximum shear rate of <NUM> RPM.

The compositions of Table <NUM> were tested for phase separation using an analytical centrifuge. The process used to test the compositions of Table <NUM> were conducted according to the following parameters: <NUM> data points collected, <NUM> second intervals, speed of <NUM> rotations per minute (rpm), a temperature of <NUM>, and for a duration of <NUM> hours. Phase separation did not occur for Compositions <NUM>-<NUM>, but there was some minor phase separation for composition <NUM>.

Samples of bovine enamel were coated with Composition <NUM>, Composition <NUM>, Composition <NUM>, and the Commercial Formula specified in Table <NUM>. The samples were tested for retention of the compositions on the enamel surfaces. In particular, an even coat of varnish was applied to the samples and then the samples were weighed. Each sample was then placed in a container including artificial saliva in an incubator with constant shaking of the container. After one hour, the samples were removed from the containers, dried, and weighed. The samples were placed in fresh artificial saliva, removed from the containers after <NUM> hours total, dried and then re-weighed after <NUM> hours. The process was repeated for <NUM> hours. Table <NUM> shows average values and standard deviation for varnish retention on bovine enamel for dental varnish compositions at different times. The varnish retention of the ethyl cellulose containing Compositions <NUM>-<NUM> was improved over the varnish retention of the Commercial Formula.

Fluoride release for Composition <NUM>, Composition <NUM>, Composition <NUM>, and the Commercial Formula of Table <NUM> was measured per gram of varnish applied to an enamel surface. The fluoride release was measured by cutting bovine enamel specimens and preparing the specimens to fit on the end of ¼ inch Plexiglas rods. The dimensions of the specimens were 6x6 mm<NUM>. The edges of the specimens were covered with nail varnish so that only enamel was exposed. The rods with specimens were identified with a unique specimen number and placed on an analytical balance (<NUM>). The balance was tarred and the exposed enamel surfaces were coated with the test material in the manner described in the instructions from the manufacturer and allowed to cure. This resulted in uniform sized samples of the varnishes having dimensions of <NUM><NUM> with a measured mass of varnish on the surface. Six specimens of each composition of Table <NUM> were prepared. The specimens were individually placed into <NUM> of deionized water with constant stirring of <NUM> rpm. After <NUM>, <NUM>, <NUM> minutes and <NUM>, <NUM> and <NUM> hours the specimens were removed from their water samples and placed in fresh deionized water. At the end of the <NUM> hours, the water samples were analyzed for fluoride content by adding <NUM> of TISAB and comparing the mv potential readings obtained to the readings obtained from a standard curve prepared at the same time and in a similar fashion. A combination fluoride electrode and a digital mv meter were used.

The cumulative amounts of fluoride released in mg per gram of dental varnish are shown for Composition <NUM>, Composition <NUM>, Composition <NUM> and the Commercial Formula in Table <NUM>.

Fluoride uptake on sound enamel and on lesioned enamel was also measured for compositions of Table <NUM>. The fluoride uptake was measured in parts per million. Table <NUM> shows fluoride uptake on sound enamel for Composition <NUM>, Composition <NUM>, Composition <NUM>, and the Commercial Formula of dental varnishes shown in Table <NUM> and Table <NUM> shows fluoride uptake on lesioned enamel for Composition <NUM>, Composition <NUM>, Composition <NUM>, and the Commercial Formula of dental varnishes shown in Table <NUM>. The mean fluoride uptake for Compositions <NUM>-<NUM> including ethyl cellulose was comparable to that of the shellac-containing Commercial Formula. The fluoride uptake was measured according to Procedure <NUM> in the FDA Monograph except that sound enamel is used in addition to incipient lesioned enamel.

Claim 1:
A dental varnish composition comprising:
a fluoride source;
a non-aqueous solvent that is ethanol:
ethyl cellulose in an amount from <NUM>% to <NUM>% by wet weight in the dental varnish composition, and
one or more resins selected from mastic, colophonium, or a combination thereof; wherein the ethyl cellulose has a viscosity no greater than <NUM> centipoise (cps); and wherein the viscosity of the ethyl cellulose is measured according to ASTM D <NUM> using <NUM>% by weight ethyl cellulose in a solution of an <NUM>:<NUM> toluene ethanol mixture by weight on a sample dried <NUM> minutes at <NUM>.