DENTURE STABILIZING COMPOSITIONS

Abstract: Disclosed are denture adhesive compositions possessing improved aesthetics and comprising a component which provides for easy removal of the adhesive from the denture and a hydrophilic powder.

Description: DENTURE STABILIZING COMPOSITIONS TECHNICAL FIELD 0 This invention relates to improvements in adhesives, i particular, improved denture adhesives. BACKGROUND OF THE INVENTION Ordinary removable dentures, dental plates, and the like comprise teeth mounted in a suitable plate or base. Denture C function as a substitute for missing teeth and serve as a replace ment for all or a portion of the teeth ordinarily found in th oral cavity. Although dentures generally are skillfully prepared often they do not fit perfectly. Moreover, no matter how satis factory at first, after a period of time the fit of the dentu 0 becomes loose and imperfect due to natural shrinkage and change in the gums, mucous tissues, and the like. Loose and imperfectl fitted dentures usually are corrected and stabilized by the use a denture adhesive. Denture adhesives are used to fill t interstices between the dentures and the gums or tissues. Pri 5 to placement of the denture in the oral cavity, a denture adhesi is applied to the denture-plate surface which, for a perfect fi should uniformly contact the gums and mucous tissues. The dentu adhesive is formulated not only for its adherent properties, b also to provide a cushion or gasket between the denture and t 30 gums or tissues, thereby positioning the denture securely in t oral cavity. Requirements and characteristics for a satisfactory dentu adhesive composition are many and are dictated by numero factors. Desirably, one daily application of such a compositi , ς should function as an effective means for insulating, cushionin and securely positioning the denture. The composition shou retain its characteristics and properties in the typical powd and cream forms during storage under various climatic conditio such as high temperature and humidity; be readily and easily capable of application to the denture surface; not be irritating or uncomfortable to the user; be safe and nontoxic; have no disagreeable odor or color; have no unpalatable taste; optionally provide antiseptic and germicidal properties for preventing or inhibiting the growth of organisms ordinarily found in the mouth; and function as an agent for prevention of putrefaction or malo¬ dorous decomposition of foods or secretions lodging beneath or adjacent to the denture. The adhesive should not attack or damage the denture. Additionally, the adhesive should be stable to bacteria, molds and enzyme systems found in the oral cavity, and have a pH that is nonirritating to the oral mucosa. The mechanical strength of the adhesive mass, be it gel or colloid, should be great enough to securely maintain the position of the denture under normal use, and not so great as to make denture removal difficult when desired, or as to damage or injure the gums, tissues or denture upon removal. There has been a considerable effort made over many years to develop improved denture adhesives. Both synthetic and natural polymers and gums have been used singly, in combination, and in combination with various additives. European Patent 64,672 to Dhabhar and Schmidt, published 11/17/82, relates to a hydrophilic denture adhesive containing an adhesive polymeric fraction comprising CMC and poly(ethylene oxide) in a hydrophilic vehicle. European Patent Application 140,486 to A.J. Desmaris, filed 7/31/84 relates to denture adhesive compositions containing a hydrophobicall modified water-soluble polymer, alone or admixed with an alkali metal salt of CMC. Hydrophobically modified hydroxyalkyl celluloses and copolymers of ethylene oxide and long chain epoxyalkanes are preferred for use in the compositions. Japanese Patent Application Hei 1-308234 to Hitoshi Matsu oto filed November 28, 1989 relates to denture stabilizer compositions consisting of inorganic and organic powders dispersed in a non- curing s licone vehicle. U.S. Patent 4,280,936 to Dhabhar, Heyd and Schmidt (issued 7/28/81), relates to improved denture adhesives containing a specified ratio of CMC and poly(ethyleneoxide) in a mineral oil base. U.S. Patent 4,474,902 to Dhabhar and Schmidt (issue 10/2/84), relates to improved denture adhesives containing karay gum in a hydrophilic vehicle. See also U.S. Patent 4,514,52 (issued 4/30/85) and U.S. Patent 4,518,721 (issued 5/21/85) t these same inventors, relating, respectively, to improved dentur adhesives containing adhesive polymeric fractions consisting o admixtures of partial salts of lower alkylvinyl ether malei anhydride-type copolymers with CMC or poly(ethyleneoxide), as wel as denture adhesives containing CMC and poly(ethyleneoxide). Se also U.S. Patent 4,522,956 (issued 6/11/85) to Dhabhar and Schmid relating to improved denture adhesives containing poly(ethylene oxide) as the sole adhesive component in a hydrophilic vehicl comprising certain polyethylene glycols. Other denture adhesives are described in U.S. Patent 4,530,942 (issued 7/23/85); 4,542,168 (issued 9/17/85); an 4,569,955 (issued 2/11/86). U.S. Patent 4,529,748 to H.G.P. ienecke (issued 7/16/85) relates to dental prosthesis adhesives formed from film-formin substances such as various cellulose derivatives, acrylat polymers, methacrylate polymers, and other film-providin substances. U.S. Patent 4,138,477 to Gaffar (issued 2/6/79) disclose oral compositions to control mouth odor containing zinc-polyme combinations formed from zinc reacted with an anionic polyme containing carboxylic, sulfonic and/or phosphonic acid radicals. Although many different approaches have been taken t formulate denture adhesives, there is still the need to develo adhesives which hold well and are more aesthetically pleasing. Yet, the search continues for denture adhesives that wil provide the above-described characteristics and, importantly, wil maintain the secure fit of the denture. In accordance with the present invention, improved aestheti characteristics are obtained in a denture adhesive composition b using a hydrophilic adhesive powder and a liquid vehicle tha cures to a peelable solid. It is an object of the present invention to provide improved denture adhesives which are easy to manufacture and that will be stable over prolonged periods in the oral cavity, yet will allow easy removal of the denture on demand. It is a further object of the present invention to provide denture adhesive compositions which provide the user with greater ease of removal of the adhesive from the dentures. It is a further object to provide such adhesives using toxicologically-acceptable, palatable materials. It is another object herein to provide adhesives that perform well in the presence of moisture, particularly in the presence of body fluids such as saliva, perspiration and blood. These and other objects are secured by the present invention, in the manner disclosed hereinafter. All percentages and ratios herein are by weight and all measurements are made at 25'C unless otherwise specified. SUMMARY OF THE INVENTION The present invention encompasses adhesive compositions com¬ prising a hydrophilic adhesive powder and a liquid vehicle that cures to a peelable solid. DETAILED DESCRIPTION OF THE INVENTION The invention relates to denture adhesive compositions which may react within the oral cavity to form a peelable solid-like product that has superior aesthetic characteristics. The compositions consist of two essential components. The first is a hydrophilic adhesive powder fraction (such as salts of lower alkyl vinyl ether/maleic anhydride copolymers, sodium carboxy methylcellulose, polyethylene oxide, karaya gum, polyethylene glycol, polyamines, polyvinyl pyrolidone, guar gum, sodium alginate, polyvinyl alcohol, polysaccharides, hydroxy ethyl cellulose, chitosan, polyacrylic acid salts, carbopol and/or. polyquats). The second is a liquid vehicle (such as 1- or 2-part Room Temperature Vulcanizable (RTV's), silicone RTV's, polyvinyl siloxanes, polyethers, polyethenes, polysulfides and/or epoxies) that cures to a peelable solid. With regard to the hydrophilic adhesive fraction, the mixed partial salts of lower alkyl vinyl ether-maleic anhydride-type copolymers, sodium carboxymethylcellulose, polyethylene oxid homopolymers, polyethylene glycol homopolymers, and karaya gum ar well known and have been used heretofore as adhesives to secur dentures. In U.S. Patent 5,073,604, December 17, 1991, issued to K Holeva et al. (incorporated herein by reference) there ar described certain hydrophilic materials comprising mixed partia salts of lower alkyl vinyl ether-maleic anhydride-type copolymers These partial salts can be utilized as all or part of the hydro philic adhesive fraction. The preparation of such a salt is described in Example I o the U.S. Patent 5,073,604 wherein the methylvinylether/mali anhydride (MVE/MA) copolymer is neutralized up to 47.5% wit calcium ion and 17.5% with zinc ions. Similarly Example I describes the preparation of 68% Ca/2% Zn, 50% Ca/20% Zn, 50 Ca/20% Zn/5% Na and 44% Ca/19% Zn/6% Na. Example V describes th preparation of various adhesive powders using Ca/Zn, Ca/Zn/N salts, karaya gum, sodium CMC, sodium borate, sodium alginate, PV and Gantrez acid. Compositions such as these can be used as th hydrophilic fraction of the present invention. Commercially available MVE/MA copolymers suitable for use i making the salts include those supplied by GAF ("Gantrez" series and DaiceTl. Sodium carboxymethylcellulose gums are more fully describe in "Chemical and Physical Properties: Cellulose Gums," 1978 published by Hercules, Incorporated, Coatings and Specialt Products Department, 910 Market Street, Wilmington, Del. 198 (incorporated herein by reference). Examples of commercially available sodium carboxymethylcellu lose gums suitable for use in this invention are those sold b Hercules, Incorporated, Wilmington, Del., as types 4H1, 7H, 9H4 7H3S, 7H0F and 7H4. Type 7H3S is preferred for use in thi invention. The ethylene oxide homopolymers possibly employed in th compositions of the invention are water soluble nonionic pol ethylene oxide (PEO) homopolymers having molecular weights of fr about 100,000 to about 5,000,000. These polymers are whi powders, which, when moistened with water, become hydrated to form a gelatinous mass with adhesive characteristics. Poly(ethylene oxide) homopolymers of this type are more fully described in "Polyox," 1978, published by Union Carbide Corporation, 270 Park Avenue, New York, N.Y. 10017, as Technical Bulletin F-44029B (incorporated herein by reference). Examples of commercially available powdered poly(ethylene oxide) homopolymers suitable for use in this invention are those polymers sold by Union Carbide Corporation under the trademark POLYOX as grades WSR N-10, WSR N-80, WSR N-750, WSR N-3000, WSR -205, WSR -1105 and WSR -301. With regard to the hydrophilic powder component, karaya gum is also well known and commercially available. Karaya gum is an adherent natural gum, readily available as a fine powder and used heretofore to secure dentures. It has the ability to swell many times its original volume upon, the addition of water to form a gelatinous or mucilaginous mass. In the compositions of this invention the adhesive component preferably comprises an effective adhesive amount of an admixture of (i) a mixed, partial salt of lower alkyl vinyl ether-maleic anhydride type copolymer (ii) CMC, (iii) PEO and/or (iv) karaya gum. With regard to the liquid vehicle component (that cures to a peelable solid), one material found useful is an RTV. One or two part RTV's are commonly used in several industries. In dentistry they are used as a dental impression material. Medical grade RTV's are used to encase pacemakers for heart patients and to coat catheters. In the electrical and electronics industries RTV's are used as encapsulates to protect delicate circuitry. Applications in the automotive industry include the use of RTV sealants for windshield installations and RTV automated gasket-forming operations. In construction, RTV sealants are used in glazing, sealing, and caulking applications. In this current invention these RTV's are used as a liquid vehicle that cures to a peelable solid in the mouth. This eliminates the ooze, grittiness and unpleasant texture and mouth feel associated with conventional denture adhesive creams and liquids. Also, this makes the product easy to clean by peeling These liquid vehicles can be silicones, polyethers, polysulfides or epoxies that cure from a liquid to a peelable solid by chemica cross-linking. Alternatively these liquids can also be reversible hydrocol loids such as agar-based elastomers which become viscous liquid in boiling water and set to an elastic gel when cooled below 35 * C In "The Encyclopedia of Chemical Technology" by Kirk-Othmer Third edition, John Wiley & Sons, 1978 (incorporated herein b reference), are described certain silicone, polyether, polysul fide, and epoxy RTV's and agar-based reversible hydrocolloids These compositions may be utilized as the liquid vehicle (tha cures to a peelable solid) in this invention. In "Silicon Compounds Register and Review" by Petrarc Systems, 1987 (incorporated herein by reference), are describe certain silicone RTV's and polymer ingredients that make up thes RTV's. Their compositions may also be utilized as the liqui vehicle in this invention. Silicone fluids, gums, greases and resins which are not RTV' can optionally be included. Suitable silicone fluids ar disclosed in U.S. Patent 4,741,855, May 3, 1988 to Grote et al This patent is incorporated herein by reference. Suitabl silicone fluids are also disclosed in Japanese patent applicatio number Hei 1-308234 to Hitoshi Matsu oto filed November 28, 1989 This patent is incorporated herein by reference. Examples of commercially available silicone RTV's may those sold by McGhan-Nusil Corporation, California (Grade CF15-2186, CF13-2186, CF21-2186 and MED 6382). Examples commercially available silicone polymers, catalysts and filte that can be blended to form suitable RTV's are those sold Bayer/Miles Inc., Pennsylvania (Baysilone U polymers, Baysilone crosslinking agents, Baysilone U catalyst Pt/6 and Baysilone basi compounds), Hulls/Petrarch America, New Jersey (catalyst PC07 polymers PS 443, PS 123 and silica SS0216), Unionr-Carbi (polymers Y12133, Y12134, Y12135, and Y12136), General Electri Company, Dow Corning Inc., Shiatsu Japan, Rhone-Poulenc France a Wacker Silicones Germany, Degussa U.S.A. (various grades silica), Cabot Corp. (silica) and Quarzwerke - Germany (cristo balite). The compositions of the present invention can optionally include from about 0.01% to about 5% of one or more components which provide the user with sensory, including flavor, benefits. Suitable components include menthol, menthyl lactate, peppermint oil, spearmint oil, peppermint oil, leaf alcohol, as well as those paramenthane carboxyamides flavoring agents available from Wilkinson-Sword (such as WS-3) which are described in U.S. Patent 4,136,163 to Watson et al., issued January 23, 1979 which is incorporated by reference herein. The compositions of the present invention are manufactured in an art-recognized manner known to those skilled in the art, such as in a powder, cream, ointment, liquid or a paste. Suitable examples of such formulations are disclosed in U.S. Patent 4,518,721, issued May 21, 1985 and U.S. Patent 4,514,528, issued April 30, 1985, both to Dhabhar et al. and both of which are hereby incorporated by reference herein. The following non-limiting examples illustrate embodiments of the subject invention wherein both essential and optional ingre¬ dients are combined. It is to be understood that these examples are for illustrative purposes only and are not to be construed as limiting the scope of the invention thereto. Example I This example illustrates the compounding of a denture adhesive composition that uses a 2-part liquid that cures to peelable solid upon mixing the 2 parts. Into two 200 cc beakers are weighed 65 gm each of a silicone RTV Part 1 and Part 2 (McGhan-Nusil Ultra-fast cure silicone elastomer CFI5-2186 and/or CF13 and/or CF21). To a separate 100 cc glass jar, 42 gms of Ca (47.5)/Zn (17.5) Gantrez salt and 28 gm of sodium CMC (Grade 7H3SX8F from Hercules) are added. This jar is then shaken well to ensure intimate mixing of the 2 powders. 35 grams of this powder blend is added to Part 1 of the RTV and the other 35 grams to Part 2 of the RTV. These powder additions are then compounded into the silicone RTV (Part 1 and Part 2 separately) using a spatula. This mixing is continued for a minimum of 5 minutes until a smooth, homogenous dispersion i obtained. The above 2-part denture adhesive liquid when mixed togethe and applied on the dentures, sticks to the dentures, sticks to th oral tissue and cures to form a peelable solid. This peelabl solid does not ooze, locks food out and is very easy to clean (b peeling) from the dentures and mouth. Example II This example illustrates the compounding of a dentur adhesive composition that uses a 2-part liquid that cures to peelable solid upon mixing the 2 parts. Into a 200 cc beaker is weighed 60 gms of Part 1 of silicone RTV (McGhan-Nusil silicone elastomer CF15-2186 and/o CF13-2186 and/or CF21-2186). Into a second 200 cc beaker i weighed 100 gms of Part B of the silicone RTV. To a separate 100 cc glass jar, 24 gms of Ca (47.5)/Zn(17. Gantrez salt and 16 gms of sodium CMC (grade 7H3SX8F fr Hercules) are added. This jar is then shaken well to ensu intimate mixing of the 2 powders. This 40 gms of powder blend i added to 60 gms of Part 1 of the silicone RTV and compounded usi a spatula. This mixing is continued for a minimum of 5 minut until a smooth, homogenous dispersion is obtained. The above 2-part denture adhesive liquid when mixed togeth and applied on the dentures sticks to the dentures, sticks to t oral tissue and cures to form a peelable solid. This peelabl solid does not ooze, locks food out and is very easy to clean ( peeling) from the dentures and mouth. Example III This example illustrates the compounding of a dentu adhesive composition that uses a 1-part RTV that is activated moisture/ saliva to form a peelable solid. Into a 200 cc beaker is weighed 80 grams of a 1-part silico RTV (Dow Corning silastic medical adhesive Cat. No. 891). To th 20 gms of Ca/Zn Gantrez salt of Example I is added. This powd additive is then compounded into the RTV using a spatula. Th mixing is continued for a minimum of 5 minutes until a smoo homogenous dispersion is obtained. The above 1-part denture adhesive when applied on the denture sticks to the dentures, sticks to the oral tissue and cures upon contact with saliva to form a peelable solid. This peelable solid does not ooze, locks food out and is very easy to clean (by peeling) from the denture and mouth. Example IV This example illustrates the compounding of a denture adhesive liquid composition that uses a 2-part RTV and a silicone oil diluent. The procedure of Example I is repeated except that 40 grams of each of the silicone RTV Part 1 and Part 2 are used in con¬ junction with 25 grams of a silicone oil (Dow Corning 245 fluid) as a diluent. The above 2-part low viscosity denture adhesive liquid when mixed together and applied on the dentures, sticks to the dentures, sticks to the oral tissue and cures to form a peelable solid. This peelable solid does not ooze, locks food out and is ery easy to clean (by peeling) from the dentures and mouth. Example V This example illustrates the compounding of a denture adhesive composition that uses a condensation cured, silicone RTV. The same procedure of Example IV is repeated except that the Ca/Zn Gantrez salt is added to the base liquid of a 2-part condensation cured silicone RTV (MED 6382 from McGhan-Nusil). When this blend is exposed to a tin catalyst it cures to a peelable solid. The above 2-part denture adhesive liquid when mixed together and applied on the dentures, sticks to the dentures, sticks to the oral tissue and cures to form a peelable solid. This peelable solid does not ooze, locks food out and is very easy to clean (by peeling) from the dentures and mouth. Example VI The compounding procedure in Example I or II is repeated with the following ingredients: 2-part Addition Cured Silicone RTV Ca/Zn Gantrez Salt CMC Ca/Na Gantrez Salt 0 0 21 In use, the above 2-part liquids/creams are placed on a dry or wet denture, and the denture is inserted in the mouth and pressed into place. Example VII The compounding procedure in Example V is repeated with the following ingredients: A (%) B (%) C XI In use, the above 2-part liquids/creams are placed on a dry or wet denture, and the denture is inserted in the mouth and pressed into place. Example VIII AJ%1 2-part Addition Silicone RTV 40 Ca/Zn Gantrez Salt 21 CMC 14 Silicone Oil 25 Vinyl End Blocked Poly Dimethyl Siloxane 0 In use, the above 2-part liquids/creams are placed on a dry or wet denture, and the denture is inserted in the mouth and pressed into place. Example IX This example illustrates the compounding of a denture adhesive composition that uses a vinyl-terminated polydimethyl siloxane, platinum catalyst, silica and polydimethyl siloxanes containing Si-H groups to generate the RTV vehicle. Into a 200 cc breaker is weighed 38.74 grams of a vinyl terminated polydimethyl siloxane (Baysilone UI), 26 grams of silica (silbond RST and Aerosil Rg74 or SS0216) 0.26 grams of platinum-silicone complex catalyst (PC075) and 35 grams of Ca/Zn Gantrez salt. This is mixed with a spatula for a minimum of 5 minutes until a smooth, homogenous dispersion is obtained. Into a second 200 cc beaker is weighed 34.5 grams of Baysilone UI, 26 grams of silica, 4.5 grams of Baysilone 430 and 35 grams of Ca/Zn Gantrez salt. This is mixed with a spatula for a minimum of 5 minutes until a smooth, homogenous dispersion is obtained. The above 2-part denture adhesive liquid/cream when mixed together and applied on the dentures, sticks to the dentures, sticks to the oral tissue and cures to form a peelable solid. This peelable solid does not ooze, locks food out, and is very easy to clean (by peeling) from the dentures and mouth.

Claims: Hhat is claimed is: 1. A denture adhesive composition comprising a mixture of: (a) an effective adhesive amount of a hydrophilic powder or liquid or mixture thereof and (b) a liquid vehicle that cures and forms a peelable solid upon 2-part mixing and/or exposure to saliva/water. 2. The composition of Claim 1 wherein component (a) is selected from the group consisting of mixed partial salts of alkyl vinyl ether aleic anhydride copolymers (AVE/MA), sodium carboxymethylcellulose (CMC), polyethylene oxide (PEO), karaya gum, polyethylene glycol (PEG), sodium alginate, hydroxyethylcellulose (HEC), chitosan, guar gum, polyacrylic acid, acid form of alkyl vinyl ether maleic anhydride copoly er, carbopol polymers, polyvinyl alcohol, polya ines, polyquaternary compounds, and mixtures thereof and component (b) is selected from the group consisting of a 1 or 2-part Room Temperature Vulcanizing (RTV) compositions selected from the group consisting of poly siloxane, polyether, polysulfide, or mixtures thereof. 3. The composition of either of Claims 1 or 2 wherein component (a) comprises mixed partial salts of AVE/MA, CMC, PEO, karaya gum and/or HEC and component (b) is a 1- or 2-part silicone RTV that cures by 2-part mixing and/or exposure to saliva/water. 4. The composition of any of Claims 1-3 wherein component (b) is an addition cured 2-part silicone RTV wherein part 1 is a blend of vinyl functional silicone polymers, and a platinum catalyst and/or silica and/or inhibitors; and part 2 is a blend of vinyl functional silicone polymers, and a hydride functional siloxanes and/or silica. 5. The composition of any of Claims 1-3 wherein component (b) is an addition cured 2-part silicone RTV wherein part 1 is a blend of vinyl-terminated polydimethyl siloxane, and a platinum-divinyltetramethyldisiloxane complex catalyst and/or silica; and part 2 is a blend of vinyl-terminated polydimethylsiloxane, and a polydi ethylsiloxane polymer containing Si-H groups and/or silica. 6. The composition of any of Claims 1-3 wherein component (b) is a 2-part condensation cured silicone RTV wherein part 1 is a blend of silanol-terminated silicone polymers, and alkoxy functional silicon compounds, and silica and/or diatomaceous earth; and part 2 is a tin and/or zinc catalyst. 7. The composition of any of Claims 1-3 wherein component (b) is a 2-part condensation cured silicone RTV wherein part 1 is a blend of silanol-terminated silicone polymers, and hydride functional siloxanes, and silica and/or diatomaceous earth; and part 2 is a tin and/or zinc catalyst. 8. The composition of any of Claims 1-3 wherein component (b) is a 1-part silicone RTV that cures by exposure to saliva/water with or without a basic additive to neutralize the acidic by-products. 9. The composition of any of Claims 1-8 wherein component (b) is converted to a 1-part system via microencapsulation. 10. The composition of Claim 2 wherein (b) is a silicone fluid, grease, gum, resin or mixtures thereof. 11. The composition of Claim 2 where (b) is a 1- or 2-part silicone RTV liquid modified to contain carboxyl , hydroxyl and/or amino functional groups. 12. A denture adhesive composition comprising a mixture of: (a) from 0% to 90% of a hydrophilic powder selected from the group consisting of AVE/MA (neutralized with calcium, zinc, sodium, strontium, iron and/or magnesium), CMC, PEO, karaya gum or HEC and mixtures thereof. (b) from 10% to 100% of a 1- or 2-part silicone RTV liquid that cures (via 2-part mixing and/or exposure to moisture) to a peelable solid. 13. The composition of Claim 12 wherein (a) is a mixed partial salt of AVE/MA copolymer (neutralized with calcium, zinc and/or sodium) and/or CMC. 14. The composition of either of Claims 12 or 13 wherein (b) is a 2-part silicone RTV.

Inventors: GRUBBS DENNIS ROBERT, MACKAY BRUCE JOHN, RAJAIAH JAYANTH, SAUD ABEL, GRUBBS, DENNIS, ROBERT, MACKAY, BRUCE, JOHN, RAJAIAH, JAYANTH, SAUD, ABEL
Applicants: PROCTER & GAMBLE, THE PROCTER & GAMBLE COMPANY
Application year: 1993
Main classification: A61K6
IPC codes: A61C13, A61K6