WO2009091949A2

WO2009091949A2 - Improved dental floss

Info

Publication number: WO2009091949A2
Application number: PCT/US2009/031209
Authority: WO
Inventors: Ralph Spindler; Stephen J. Urbanec
Original assignee: Amcol International Corporation
Priority date: 2008-01-18
Filing date: 2009-01-16
Publication date: 2009-07-23
Also published as: WO2009091949A3

Abstract

A dental floss incorporating an active agent loaded onto polymeric microparticles is disclosed.

Description

IMPROVED DENTAL FLOSS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. provisional patent

Application No. 61/021,952, filed January 18, 2008, incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to an improved delivery system for active agents incorporated onto a dental floss.

BACKGROUND OF THE INVENTION

[0003] Tooth decay and dental disease can be caused by bacterial action resulting from the formation of plaque about the teeth and/or food particles trapped between the teeth. The removal of plaque and trapped food particles reduces the incidence of caries, gingivitis, and mouth odors, as well as generally improving oral hygiene. Conventional brushing is inadequate for removing all trapped food particles and plaque. Therefore, to supplement brushing, dental flosses have been long recommended. Dental floss is a thin thread or plastic ribbon used to remove food and dental plaque from between teeth. The term "dental floss", as used herein, includes dental flosses, dental tapes, dental ribbons, and any similar article. [0004] Dental flosses prepared from multiple filaments twisted to form a thread and coated with a microcrystalline wax to prevent fraying during manufacture and use are well known. Active agents have been applied to dental flosses to provide interproximal and sublingual benefits, such as whitening. [0005] In addition flavors have been added to a dental floss. This is accomplished using starch-based encapsulates where the problems can be a very low loading of the flavor (25% or less) and the fragile nature of the encapsulate, which makes it difficult to the process the final dental floss without prematurely bursting the capsule. This approach also is limited to hydrophobic active agents. Finally, there is little that can be done to either modify the release characteristics of the capsules or improve the stability of the active agent incorporated into the capsule. [0006] The manufacture of such dental flosses therefore has proved difficult because of active agent losses during manufacture of the floss, or during storage of the floss. An effective delivery of the active agent between the teeth also has proven elusive. The present invention is directed to a dental floss having a delivery system for an active ingredient that is easy and economical to manufacture, and achieves improved results in the flossing of teeth.

SUMMARY OF THE INVENTION

[0007] The present invention is directed to the use of a microparticle delivery system to effectively position active agents and esthetic agents between the teeth from a dental floss, and to extend the release of active agents and esthetic agents between the teeth. One advantage of microparticle delivery systems is the ability to incorporate hydrophobic and/or hydrophilic actives into a dental floss product. In addition, the microparticle delivery system can be deposited onto the surface of the tooth and gum tissue during application of the dental floss, and thereby act as a reservoir for the active agent, e.g. a flavor, present in the microparticle delivery system. Improved efficacy results because the active agent resides in the oral cavity for a longer time. [0008] Another advantage is that a microparticle delivery system improves the stability of the active agent both during the process of incorporating the active agent into the dental floss and during storage of the dental floss. This is especially important for volatile ingredients, where a microparticle delivery system has been shown to increase the time the active agent remains in the microparticle. [0009] Among the active agents that can be incorporated into a dental floss in accordance with the present invention are antibacterial agents, such as triclosan, cetyl pyridinium chloride, and sodium chlorite; tooth whitening agents, such as hydrogen peroxide, sodium percarbonate, and sodium perborate; antiplaque deposition aides, such as silicone polymers; flavors, including flavors that are incompatible with oral care formulations; carries prophylactics, like sodium fluoride, stannous, fluoride, and sodium monofluorophosphate; and other active agents that can improve overall oral cavity health.

[0010] One aspect of the present invention therefore is to provide a dental floss product comprising a substrate prepared from one or more filament having a microparticle delivery system applied thereto. The polymeric microparticles contain an active agent that can perform its intended function upon application to tooth and gum surfaces, and/or the microparticles are deposited on tooth and gum surfaces to perform an intended function for extended time periods by a slow release of the active agent from the microparticles.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A dental floss of the present invention comprises a substrate material having a polymeric microparticle delivery system applied thereto. The polymeric microparticles are loaded with an active agent, such as a flavor, tooth whitener, or antibacterial, prior to application of the microparticles onto the substrate. The term "dental floss" as used herein means dental flosses, dental tapes, dental ribbons, and similar articles.

[0012] A dental floss of the present invention comprises a substrate, typically in the form of a thread prepared from one or more filament. The substrate can be fabricated from either natural or synthetic sources, examples of which include, but are not limited to, filaments or yarns of high and normal tenacity polymers, nylons, polyolefins, polyethylenes, polypropylenes, fluorocarbon compounds, polytetrafluoroethylenes, rayons, dacrons, acrylics, acetate polymers, and other plastics, alone or in combination. Natural substances include, but are not limited to, cotton, wool, silk, linen, and other staple fibres, alone or in combination. Blends of synthetic and natural fibres can also be used. Synthetic filaments are preferred because they are more durable, stronger, generally less expensive, and easier to work and procure. Preferred substrates are nylon, prepared from filaments being twisted or otherwise woven together to provide a non-fraying end. [0013] The length, diameter, structure, and design of the substrate is not limited to any specific size, shape, arrangement, or configuration, and thus, can be fabricated to suit any specific intention. The substrate can, for example, comprise a plurality of individual filaments that have been formed together to give a larger thread having a sufficiently small diameter to permit insertion between the teeth. It also can comprise a composite multifilament yarn bonded to an extruded monofilament or to another multifilament yarn. A single circular, square, or rectangular shaped monofilament thread is also useful. Other variations are well known in the art, and are also useable in the invention disclosed herein.

[0014] A present dental floss has an active agent applied thereto using a polymeric microparticle delivery system. The active agent is loaded onto the polymeric microparticles prior to application of the polymeric microparticles to the substrate, typically with the assistance of a binding agent.

[0015J Absorbent polymeric microparticles useful in the present invention have an ability to absorb several times their weight of a liquid compound, such as an oral care compound. One preferred class of adsorbent microparticles is prepared by a suspension polymerization technique, as set forth in U.S. Patent Nos. 5,677,407; 5,712,358; 5,777,054; 5,830,967; 5,834,577, 5,955,552; and 6,107,429, each incorporated herein by reference (available commercially under the tradename of POLY-PORE^® E200, INCI name, allyl methacrylate copolymer, from AMCOL International, Hoffman Estates, IL). Another preferred class of adsorbent microparticles is prepared by a precipitation polymerization technique, as set forth in U.S. Patent Nos. 5,830,960; 5,837,790, 6,248,849; and 6,387,995, each incorporated herein by reference (sold under the tradename of POLY-PORE* L200 by AMCOL International, Hoffman Estates, IL). These adsorbent microparticles also can be modified after the incorporation of an active compound to modify the rate of release of such a compound, as set forth in U.S. Patent No. 6,491,953, incorporated herein by reference.

[0016] Another useful class of adsorbent polymers prepared by a precipitation polymerization technique is disclosed in U.S. Patent Nos. 4,962,170; 4,948,818; and 4,962,133, each incorporated herein by reference, and are commercially available under the tradename POLYTRAP from AMCOL International. Other useful, commercially available adsorbent polymers include, for example, MICROS PONGE* (a copolymer of methyl methacrylate and ethylene glycol dimethacrylate), available from AMCOL International and PoIy-HlPE polymers (e.g., a copolymer of 2- ethylhexyl acrylate, styrene, and divinylbenzene) available from Biopore Corporation, Mountain View, California.

[0017] In particular, the adsorbent polymer microparticles prepared by the suspension polymerization technique, e.g., POLY-PORE* E200, are a highly porous and highly crosslinked polymer in the form of open (i.e., broken) spheres and sphere sections characterized by a mean unit particle size of about 0.5 to about 3,000 microns, preferably about 0.5 to about 300 microns, more preferably about 0.5 to about 100 microns, and most preferably about 0.5 to about 80 microns. A significant portion of the spheres is about 20 microns in diameter.

[0018] The polymeric microparticles are oil and water adsorbent, and have an extremely low bulk density of about 0.008 gm/cc to about 0.1 gm/cc, preferably about 0.009 gm/cc to about 0.07 gm/cc, and more preferably about 0.0095 gm/cc to about 0.04-0.05 gm/cc. The microparticles are capable of holding and releasing oleophilic (i.e., oil soluble or dispersible), as well as hydrophilic (i.e., water soluble or dispersible), active agents, individually, or both oleophilic and hydrophilic compounds simultaneously.

[0019] The adsorbent polymer microparticles prepared by the suspension polymerization technique include at least two polyunsaturated monomers, preferably allyl methacrylate and an ethylene glycol dimethacrylate, and, optionally, monounsaturated monomers. The microparticles are characterized by being open to their interior, due either to particle fracture upon removal of a porogen after polymerization or to subsequent milling. The microparticles have a mean unit diameter of less than about 50 microns, preferably less than about 25 microns, and have a total adsorption capacity for organic liquids, e.g., mineral oil, that is at least about 72% by weight, preferably at least about 93% by weight, and an adsorption capacity for hydrophilic compounds and aqueous solutions of about 70% to about 89% by weight, preferably about 75% to about 89% by weight, calculated as weight of material adsorbed divided by total weight of material adsorbed plus dry weight of polymer. In a preferred embodiment, the broken sphere microparticles are characterized by a mean unit diameter of about 1 to about 50 microns, more preferably of about 1 to about 25 microns, most preferably, of about 1 to about 20 microns.

[0020] Preferred polymeric microparticle delivery systems comprise a copolymer of allyl methacrylate and ethylene glycol dimethacrylate, a copolymer of ethylene glycol dimethacrylate and lauryl methacrylate, a copolymer of methyl methacrylate and ethylene glycol dimethacrylate, a copolymer of 2-ethylhexyl acrylate, styrene, and divinylbenzene, and mixtures thereof. Specific polymeric microparticles useful in the present invention can be the previously described POLY- PORE^® E200, POLY-PORE^® L200, POLYTRAP, M1CROSPONGE, or PoIy-HIPE particles, for example.

[0021] To function as a delivery system for an active agent, the active agent is incorporated loaded onto and/or entrapped in the microparticles. This can be accomplished by spraying or adding the active agent either directly to the microparticles in such a manner that an essentially homogeneous distribution of the active agent is achieved on all the microparticles. Alternatively, if the active agent is a crystalline material, the active agent is first dissolved in a suitable volatile solvent, the resulting solution is added to the microparticles, then the volatile solvent is removed under vacuum with gentle heating. Another method for loading a crystalline active agent that is not readably soluble in an appropriate volatile solvent is to first disperse the agent in a suitable carrier, such as polyether or polyol, and then add the dispersion directly to the microparticle delivery system. In some cases, these processes are repeated several times to achieve a loading level of the active agent on the polymeric microparticles that is desired.

[0022] The load of active agent, as 100% active agent, added to the polymeric microparticles is about 1 to about 67 wt.% (by weight of the loaded polymeric microparticles), in a preferred amount of about 5 to about 50 wt.%, or in a more preferred amount of about 10 to about 37.5 wt.%.

[0023] In some embodiments, the active agent is further protected by adding a second material, usually a liquid or waxy material as a barrier layer, to the microparticle after the active agent has been entrapped, or loaded, onto the microparticle. This is especially effective for reactive agents like cetyl pyridinium chloride and sodium tripolyphosphate. After entrapping the active ingredient, a barrier layer (i.e., a secondary entrapment or loading), optionally, can be applied to the loaded microparticle to prevent a rapid diffusion of the active agent from the microparticle. Also, the melting point of the barrier layer can be selected such that it melts higher than the highest temperature that the dental floss will be exposed to either during storage of the dental floss or during accelerated aging of the dental floss. [0024] Examples of materials that can be used as a barrier layer or a secondary entrapment, include, but are not limited to, low melting alcohols (Cg through C₂₀) and fatty alcohols ethoxylated with one to three moles of ethylene oxide. Examples of fatty alcohols and alkoxylated fatty alcohols include, but are not limited to, behenyl alcohol, caprylic alcohol, cetyl alcohol, cetaryl alcohol, decyl alcohol, lauryl alcohol, isocetyl alcohol, myristyl alcohol, oleyl alcohol, stearyl alcohol, tallow alcohol, stearety-2, ceteth-1, cetearth-3, and laureth-2. Additional fatty alcohols and alkoxylated alcohols are listed in the International Cosmetic Ingredient Dictionary and Handbook, Tenth Edition, Volume 3, pages 2127 and pages 2067-2073 (2006), incorporated herein by reference,

[0025] Another class of materials that can be used a barrier layer is the C₈ to

C ₁₂ fatty acids, including, but not limited to, stearic acid, capric acid, behenic acid, caprylic acid, lauric acid, myristic acid, tallow acid, oleic acid, palmitic acid, isostearic acid and additional fatty acids listed in the International Cosmetic Ingredient Dictionary and Handbook, Tenth Edition, Volume 3, page 2126-2127, incorporated herein by reference.

[0026] The barrier material also can be a hydrocarbon, like mineral oil, 1 - decene dimer, polydecene, paraffin, petrolatum, vegetable-derived petrolatum or isoparafln. Another class of barrier materials is waxes, like mink wax, carnauba wax, and candelilla wax, for example, and synthetic waxes, like silicone waxes, polyethylene, and polypropylene.

[0027] Fats and oils can be useful barrier material agents, which include, for example, but are not limited to, lanolin oil, linseed oil, coconut oil, olive oil, menhaden oil, castor oil, soybean oil, tall oil, rapeseed oil, palm oil, and neatsfoot oil, and additional fats and oils listed in the International Cosmetic Ingredient Dictionary and Handbook, Tenth Edition, Volume 3, pages 2124-2126. [0028J Other useful classes of barrier materials include a water-insoluble ester having at least 10 carbon atoms, and preferable 10 to about 32 carbon atoms. Numerous esters are listed in International Cosmetic Ingredient Dictionary and Handbook, Tenth Edition, pages 21 15-2123.

[0029] Alternatively, an active agent can be admixed with a molten waxy material, then entrapped in a microparticle delivery system. In the case of liquid active agents, waxy materials disclosed above as barrier materials also can be used as an additive for thickening the liquid active agents, and thereby helping to minimize premature diffusion of the active agent from the microparticle.

[0030] The range of the waxy material to the delivery system is from about 10 to about 67 wt. %, based on the final weight of the loaded polymeric microparticles. In a more preferred embodiment, the range of waxy material to the loaded polymeric microparticles can be about 25 to about 50 wt.%, based on the final weight of the loaded polymeric microparticles.

[0031] Active agents loaded onto the microparticles include flavors, tooth whitening agents, and antibacterial agents, for example. The dental floss can contain more than one active agent, either with microparticles containing one or more of the active ingredients, or different microparticles each containing a different active agent, or any combination thereof.

[0032] In accordance with the present invention, a present dental floss can contain one or more flavor. A flavor incorporated into a polymeric microparticle can comprise essential oils, synthetic flavors, or mixtures thereof, including, but not limited to, oils derived from plants and fruits, such as citrus oils, fruit essences, mint, peppermint oil, spearmint oil, clove oil, oil of wintergreen, anise, sassafras, sage, saccharin, thymol, menthol, eucalyptus, marjoram, cinnamon, lemon, orange, banana, cherry, apple, pineapple, grape, strawberry, blueberry, tutti frutti, methyl salicylate, and the like. Persons skilled in the art recognize that natural and artificial flavoring agents can be used independently or combined to provide a desired blend. All such flavors and flavor blends are contemplated by the present inventions. [0033] In another embodiment, a present dental floss comprises a polymeric microparticle delivery system having an antibacterial agent incorporated therein. The antibacterial agent can be one or more of triclosan, cetyl pyridinium chloride, a halogenated diphenyl ether, sodium tripolyphosphate, a halogenated salicylanilide, a halogenated carbanilide, benzalkonium chloride, hexachlorophene, and stannous pyrophosphate, and sodium chlorate, for example.

[0034] In yet another embodiment, the dental floss comprises a polymer microparticle delivery system having a tooth whitening agent incorporated therein. The tooth whitening agent can be, for example, one or more peroxide based compound, such as, but not limited to, hydrogen peroxide, calcium peroxide, sodium perborate, sodium carbamate peroxide, potassium peroxydiphosphate, organic peracids, and sodium carbonate peroxide. Their use helps remove dental plaques and whiten teeth, and thereby reduces the incidence of dental caries and other related diseases. In addition, peroxide based compounds are alkaline in nature, and therefore help facilitate the neutralization of oral acids.

[0035] The active agent also can be an antiplaque deposition aid, such as a silicone polymer; or a caries prophylactic, such as sodium fluoride, stannous fluoride, or sodium monofluorophosphate,

[0036] To incorporate a microparticle delivery system into a dental floss, the microparticles, including the active agent loaded onto the microparticles and any optional protective coating materials, are formed into a coating solution, which then is applied to the dental floss. The coating solution can be a molten waxy material or volatile solvent that contains the loaded microparticles, as well as a suitable binding agent such that when the solvent is evaporated, the microparticle remains attached or adhered to the surface of the dental floss.

[0037] Binding agents include, but are not limited to film-forming polymers, such as polyvinyl alcohol, polyvinylpyrrolidone, and cellulose ethers, such as carboxymethylcellulose. Additional binders include, but are not limited to acrylates copolymer, aery lic/acry late copolymer, agar, algin, alginic acid, ammonium acrylates copolymer, ammonium alginate, ammonium vinyl acetate/acrylates copolymer, beeswax, behenyl alcohol, butyl ester of ethylene/maleic anhydride copolymer, candelilla wax, carboxymethyl hydroxyethylcellulose, carnauba, carrageenan, cellulose gum, ceresin, collodion, corn flour, corn starch, dextran, dextrin, dihydroabietyl alcohol, distarch phosphate, ethylcellulose, ethylene/acrylate copolymer, ethylene/maleic anhydride copolymer, ethylene/vinyl acetate copolymer, gelatin, glyceryl starch, guar gum, hydrogenated jojoba wax, hydrogenated rice bran wax. hydroxybutyl methylcellulose, hydroxyethylcellulose, hydroxyethyl ethylcellulose, hydroxypropylcellulose, hydroxypropyl guar, hydroxypropyl methylcellulose, isopropyl ester of PVM/MA copolymer, isopropyl myristate, isopropyl palmitate, isopropyl stearate, isostearic acid, isostearyl isostearate, Japan wax, karaya gum, lanolin alcohol, lanolin wax, locust bean gum, maltodextrin, mannitol. methylcellulose, microcrystalline wax, montan acid wax, montan wax, oleostearine, ouricury wax, ozokerite, pectin, PEG-75, PEG-150, PEG-350, PEG-2M PEG-5M, PEG-7M, PEG9M, PEG-14M, PEG-20M, PEG-23M, PEG-45M, PEG-90M, PEG-115M, polyacrylamide, polyacrylic acid, polybutene, polydipentene, polyethylacrylate, polyethylene, polyisobutene, polyvinyl acetate, polyvinyl butyral, polyvinyl laurate, polyvinyl methyl ether, potassium alginate, potassium carrageenan, potato starch, PPG-20 methyl glucose ether, propylene glycol alginate, PVM/MA copolymer. PVP, PVP/dimethylaminoethylmethacrylate copolymer, PVP/eicosene copolymer, PVP/eicosene copolymer, PVP/ethyl methacrylate/methacrylic acid copolymer, PVP/hexadecane copolymer, PVP/VA copolymer, PVP/vinyl acetate/itaconic acid copolymer, rice bran wax, rosin, shellac, shellac wax, sodium acrylate/vinyl alcohol copolymer, sodium C4-12 olefin/maleic acid copolymer, sodium carboxymethyl dextran, sodium carrageenan, sodium cellulose sulfate, sodium magnesium fluorosilicate, sodium magnesium silicate, sodium polymethacrylate, styrene/maleic anhydride copolymer, synthetic beeswax, synthetic wax, tallow glyceride, tallow glycerides, tragacanth gum, vinyl acetate/crotonates copolymer, vinyl acetate/crotonic acid copolymer, wheat gluten, wheat starch, and xanthan gum.

EXAMPLES

[0038] Example 1 Loading of Triclosan. To 37.5 g of isopropyl alcohol was added 12.5 g of triclosan (IRGACARE MP, Ciba). The solution was stirred until the triclosan was completely solubilized. The loading solution was added slowly to 50 g of POLYTRAP with sufficient stirring and for an extended period of time to ensure that the loading was homogeneous. The loaded POLYTRAP was placed in a vacuum oven at 45°C and dried until the isopropyl alcohol was essentially completely removed. This loading process was repeated three additional times until the final load of triclosan in the POLYTRAP was equal to weight of the polymer resulting in a 1 :1 load of triclosan in POLYTRAP.

[0039] Example 2 To 25 g of the 1 :1 loaded triclosan described in Example 1 was added 37.5 g of shea butter that first was melted at 80⁰C, then cooled to 45°C, before addition to the loaded POLYTRAP in a stepwise process which provided a final composition containing 20% triclosan, 20% POLYTRAP and 60% shea butter, by weight.

[0040] Example 3 To 15 g of the triclosan loading described in Example 1 was added 30 g of a solution containing 1 :1 blend of dimethicone (60,000 cst) and hexanes. The solution was added in stepwise process with sufficient agitation to provide a homogeneous loading. The resulting loaded microparticles then were placed in a vacuum oven at 40⁰C overnight to give a final composition containing 25% POLYTRAP, 25% triclosan, and 50% dimethicone, by weight. [0041] Example 4 A solution containing 10 g sodium tripolyphosphate was added to 100 g of deionized (DI) water, then the resulting solution was stirred until homogeneous. The solution was added to 100 g of POLY-PORE® E200 microparticles in a stepwise process with sufficient stirring to ensure that the loading solution was homogeneously distributed. The resulting product was placed in a vacuum oven at 50⁰C, then the material was dried until essentially all the water was removed. A second loading solution was prepared containing the same ratios of sodium tripolyphosphate and water as above, and this solution was added to the dried loaded POLY-PORE® E200 particles in a similar stepwise process. The resulting loaded microparticles were placed in the vacuum oven at 50⁰C, then dried until the water was essentially completely removed. The final composition contained 16.7% sodium tripolyphosphate and 83.3% POLY-PORE® E200, by weight. [0042 J Example s A dispersion of sodium percarbonate in polyethylene glycol (PEG, MW ca. 400) was prepared by adding 125.25 g of sodium percarbonate to 254.29 g of PEG. The components were mixed with a dispersion blade at sufficient speed to ensure that the sodium percarbonate was uniformly admixed with the PEG. To 91.4 g of POLYTRAP was added 365.5 g of the sodium percarbonate dispersion. The dispersion was slowly added in a stepwise process with sufficient mixing to

1 - ensure that loading was homogeneous. The final composition contained 26% sodium percarbonate, 54% PEG. and 20% POLYTRAP, by weight.

[0043] Example 6 A cetyl pyridinium chloride loading was prepared by first dissolving 60 g of cetyl pyridinium chloride in 240 g of denatured ethanol, then stirring the mixture until the cetyl pyridinium chloride was completely dissolved. The resulting solution then was added to 100 g of POLY-PORE® E200 in a stepwise fashion with sufficient mixing to ensure that the loading solution was completed dispersed onto the polymer. The resulting loaded delivery system was placed in a vacuum oven and dried at 50⁰C under vacuum until essentially all the solvent was removed. The final composition contained 37.5% cetyl pyridinium chloride and 62.5% POLY-PORE® E200, by weight. Similar loaded microparticles were prepared by substituting POLY-PORE® E200 with POLYTRAP.

[00441 Example 7 To 10 g of a loading of 37.5% cetyl pyridinium chloride on POLYTRAP was added 10 g of stearyl alcohol that first was heated to 80⁰C. The stearyl alcohol was added to the loaded POLYTRAP in a stepwise process using sufficient stirring to ensure that the microparticles were uniformly coated. The final composition contained 18.7% cetyl pyridinium chloride, 50% stearyl alcohol, and 31.3% POLYTRAP, by weight. A similar loading was prepared wherein the final composition contained 12.4% cetyl pyridinium chloride, 67% stearyl alcohol, and 20.6% POLYTRAP, by weight.

[0045] Example 8 To 72 g of a 37.5% loading of cetyl pyridinium chloride on POLYTRAP was added 144 g of shea butter that first was melted at 80⁰C, then added in a stepwise process with sufficient stirring to homogeneously incorporate the shea butter throughout the loaded POLYTRAP. The final composition contained 12.4% cetyl pyridinium chloride, 67% shea butter, and 20.6% POLYTRAP, by weight.

[0046] Example 9 A loading of dimethicone (50 cst) in POLYTRAP was prepared by directly adding 400 g of dimethicone to 100 g of POLYTRAP to provide a composition that contained 80% dimethicone and 20% POLYTRAP, by weight. [0047] Example 10 A loading of peppermint flavor on POLY-PORE® E200 was prepared by adding 140.5 g of peppermint flavor (Bell Flavors & Fragrances) to 46.8 g of POLY-PORE®. The oil was added in a stepwise process with sufficient mixing to ensure that a homogeneous loading of the oil on the microparticles. [0048] Obviously, many modification and variations of the invention as hereinbefore set forth can be made without department from the spirit and scope thereof and, therefore, only such limitations should be imposed as are indicated by the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A dental floss comprising a substrate and polymeric microparticles loaded with an active agent selected from the group consisting of an antibacterial agent, a flavor, a tooth whitening agent, an antiplaque deposition aid, a caries prophylactic, and mixtures thereof.

2. The dental floss of claim 1 wherein the polymeric microparticles are highly crosslinked and are derived from methacrylate monomers, acrylate monomers, or mixtures thereof.

3. The dental floss of claim 1 wherein the polymeric microparticles comprise an allyl methacrylate copolymer, an ethylene glycol dimethacrylate/allyl methacrylate copolymer, a lauryl methacrylate/ethylene glycol dimethacrylate copolymer, and mixtures thereof.

4. The dental floss of claim 1 wherein the polymeric microparticles are selected from the group consisting of a copolymer of allyl methacrylate and ethylene glycol dimethacrylate, a copolymer of ethylene glycol dimethacrylate and lauryl methacrylate, a copolymer of methyl methacrylate and ethylene glycol dimethacrylate, a copolymer of 2-ethylhexyl acrylate, styrene, and divinylbenzene, and mixtures thereof.

5. The dental floss of claim 1 wherein the polymeric microparticles comprise a copolymer of allyl methacrylate and ethylene glycol dimethacrylate, a copolymer of ethylene glycol dimethacrylate and lauryl methacrylate, or a mixture thereof.

6. The dental floss of claim 5 wherein the polymeric microparticles comprise copolymer of ethylene glycol dimethacrylate and lauryl methacrylate.

7. The dental floss of claim 1 wherein the active agent is present in the polymeric microparticles in an amount of about 1% to about 67%, by weight of the loaded microparticles.

8. The dental floss of claim 1 wherein the active agent is present in the polymeric microparticles in an amount of about 5% to about 50%, by weight of the loaded microparticles.

9. The dental floss of claim 1 wherein the active agent is present in the polymeric microparticles in an amount of about 10% to about 37.5%, by weight of the loaded microparticles.

10. The dental floss of claim 1 wherein the antibacterial agent comprises one or more of triclosan, cetyl pyridinium chloride, sodium chlorate, sodium tripolyphosphate, a halogenated diphenyl ether, a halogenated salicylanilide, a halogenated carbonilide, benzolkonime chloride, hexachlorophene, and stannous pyrophosphate.

11. The dental floss of claim 1 wherein the whitening agent comprises one or more of hydrogen peroxide, sodium percarbonate, sodium perborate, sodium carbonate peroxide, calcium peroxide, potassium peroxydiphosphate, organic peracids, and sodium carbamate peroxide.

12. The dental floss of claim 1 wherein the flavor is present in the polymeric microparticles in an amount of about 1% to about 80%, by weight of the loaded microparticles.

13. The dental floss of claim 1 wherein the flavor is present in the polymeric microparticles in an amount of about 5 to about 75%, by weight of the loaded microparticles.

14. The dental floss of claim 1 wherein the flavor is present in the polymeric microparticles in an amount of about 10% to about 67%, by weight of the loaded microparticles.

15. The dental floss of claim 1 wherein the caries prophylactic comprises one or more of sodium fluoride, stannous fluoride, and sodium monofluorophosphate.

16. The dental floss of claim 1 wherein the antiplaque deposition aid comprises a silicone polymer.

17. The dental floss of claim 1 wherein the polymeric microparticles further comprise a barrier layer.

18. The dental floss of claim 17 wherein the polymeric microparticles comprise a barrier layer in an amount of about 10% to about 67% of the total weight of the loaded polymeric microparticles.

19. The dental floss of claim 18 wherein the polymeric microparticles comprise a barrier layer in an amount of about 20% to about 50% of the total weight of the loaded polymeric microparticles.

20. The dental floss of claim 1 further comprising a binding agent.

21. The dental floss of claim 1 wherein the substrate comprises one or more filament formed into a thread.