IE56280B1 - Oral product for controlling gingivitis - Google Patents

Abstract

An oral composition for treating gingivitis and periodontitis comprising an oral vehicle and an effective amount of the water insoluble antigingivitis agent, imidazoyl-1-(p- chlorophenoxy)-3,3-dimethyl 2- butanone (also known as Climbazole) solubilized in a nonionic compound containing a mixture of hydrophobic and hydrophilic groups of sufficient length to effect solubilization in an aqueous vehicle, in the weight ratio of 1:1 to 25:1 and preferably 3:1 to 25:1 solubilizer:imidazoyl compound, said agent being selectively effective against the gram negative anaerobic micro-organisms associated with periodontitis.

Description

The present invention relates to an antibacterial-containing oral composition which promotes oral hygiene, controls plaque formation, gingivitis and periodontitis, by the topical application to the oral cavity, of a mouthrinse or dentifrice containing an effective amount of the antigingivitis agent, 1- imidazoyl-l-(p-chlorophenoxy)~3,3-diraethyl 2- butanone (Climbazole by Bayer).

Periodontitis, or pyorrhea, is a disease affecting the supporting tissues of the teeth including the gingiva, the membrane lining the sockets in which the teeth lie, and the bones surrounding the teeth. The disease may initially be associated with conditions of constant irritation of the gingiva by dental plaque, food impaction, poor dental restorations, traumatic occlusion, or chemical irritants .

The gums may be seriously harmed by deposits of dental plaque, a combination of minerals and bacteria found in the mouth. The bacteria associated with plaque can secrete enzymes and endotoxins which can irritate the gums and cause an inflammatory gingivitis. As the gums become increasingly irritated by this process they have a tendency to bleed, lose their toughness and resiliency, and separate from the teeth, leaving periodontal pockets in which debris, secretions, more bacteria and toxins further accumulate. It is . . also possible for food to accumulate in these pockets, thereby providing nourishment for increased growth of bacteria and production of endotoxins and destructive enzymes. The pus that forms in this process is capable of destroying gum and bone tissue. Bacteria are generally found to be present during the active stages of periodontal disease.

Such organisms as anaerobic gram negative bacteria are usually present, and are found in the purulent discharge as well as in the involved tissue, and may be absorbed into the general system through the lymphatic glands or venous blood stream.

The progression of the pyorrheic process usually begins with gingivitis, initiating at the margins of the gums, in which the gingiva become more tender and sensitive, and appear flabby, inflamed and swollen. Periodontal pockets become apparent, and infection takes place in these pockets. Effective control and prevention of gingivitis accordingly constitutes a desideratum for the prevention of further periodontal diseases.

A multitude of materials have been previously proposed and employed for controlling oral diseases and malfunctions such as plaque, calculus, tartar, caries, halitosis, and periodontal diseases such as gingivitis and pyorrhea, but none have been entirely satisfactory. For example, oral compositions containing anti-inflammatory agents which reduce the symptoms of swelling, bleeding and inflammation associated with gingivitis, by preventing tartar <9 - 3 5. . . . . . formation and/or countering oral calculus, include an imidazole such as histadine or histamine as disclosed in U.S. Patent No. 3,497,591; a dichloro2-guanidino benzimidazole, as disclosed in U.S. Patent No. 3,523,154; carragheenin as disclosed in U.S. Patent No. 4,029,760; a mixture of tranexamic acid and folic acid, as disclosed in U.S. Patent No. 4,272,512; and tannic acid, as disclosed in U.S. Patent No. 4,273,758. All of aforesaid agents are non-antimicrobial.

U.S. Patent No. 3,577,520 also discloses a denti frice composition containing 5,5-diaryl-2,4-imidazol idinediones in the treatment of pyorrhea, by repairing the lesions of paradontosis.

U.S. Patent No. 3,911,133 discloses an antibacterial composition effective against both gram positive and gram negative bacteria, comprising an imidazole derivative, which is a bis(imidazolium quaternary salt), useful in mouthwashes, toothpastes and dental gels as a method of inhibiting the formation of dental plaque or in the prevention of gingivitis .

U.S. Patent No. 4,243,670 discloses imidazolium derivatives having strong antimicrobial activity against dermatophytes, yeasts, moulds, biphase fungi and gram positive cocci; and useful as an additive to oral hygiene products such as toothpastes and mouthwashes, to avoid microbially caused infections of the mucosa of the mouth and as a prophylactic against infection. - 4 It is also known in the art, that certain gram negative organisms such as Bacteriodes asaccharolyticus or Bacteriodes gingivalis are associated with adult periodontitis. By eliminating these and other . gram negative anaerobic bacteria from the plaque accumulated on the gingival tissues, effective control and prevention of periodontal disease can be achieved.

Accordingly, it has been shown by Listgarton et . al in the J. Periodont. Res. 14: 65-75 (1979), that metronidazole, CH2CH2OH . . . given systematically causes the elimination of the said gram negative anaerobes from the plaque. This was substantiated by Heijl and Lindhe in the J. Clinical Periodontology 6, 197-209 (1979), wherein is shown that metronidazole is effective in reducing plaque and gingivitis scores in dogs; and by Loesche et al in the J. of Clinical Periodontology, 8: 29-44 (1981) , wherein it is shown that metronidazole is effective in reducing the anaerobic B. asaccharolytlcus count in plaque removed from periodontal pockets, concoinmiCantly, with a substantial reduction in pocket depth and considerable gain in apparent attachment. However, metronidazole, sold under the tradename of Flagyl, is carcinogenic (Physician . Reference Handbook p. 1761) and cannot be used indiscriminately.

It has now been found that another derivative of imidazole is effective against said gram negative anaerobic organisms, which is nonrautagenic, non10. carcinogenic and can be topically applied to the oral cavity in the treatment of gingivitis, namely, 1-imidazoyl-l-(p-chlorophenoxy)-3,3-diraethyl 2butanone.

The imidazoyl ketones such as 1-imidazoyl-l-(4 . chlorophenoxy)-3,3-diraethyl 2-butanone, are disclosed in U.S. Patent Nos. 3,812,142 and 3,903,287 as an anti-mycotic agent, useful in pharmaceutical compositions including pastes, gels, creams, aqueous and nonaqueous suspensions. Its . action against pathogenic protozoa, gram positive and negative bacteria such as Staphlococci and Escherichia coli is also noted herein. British Patent No. 1,502,144 and its German counterpart, Patent No. 2,430,039, disclose hair or skin treating . compositions, effective against Pityrosporum ovale, containing the imidazoyl ketone antimycotic agents dispersed in a dermatologically acceptable carrier which contains a detergent-active compound. These compositions are in the form of creams, aerosols, . powders and liquids. German Patent No. 2,600,800 - 6 discloses the l-imidazoyl-l-(4-chlorophenoxy)-3,3dimethyl 2-butanone in a fungicidal composition, either in dry form, as a dispersion in water, waterin-oil or oil-in-water emulsion or a spray, useful . for protecting plaster coatings, dispersion dyes, wall-paper, tiled surfaces, paints, glues, bitumina, furniture, leather, shower curtains, textiles, carpets, wood and paper, against a long list of pathogenic fungi, moulds and bacteria. However, . there is no mention of Bacteroides asaccharolyticus or gingivalis, the particular anaerobic gram negative organisms found in gingivitis. German Patent No. 2,700,806 also discloses a mixture of the imidazoyl ketone fungicide and a quaternary ammonium . bactericide useful for protecting materials such as paints, glues, bitumen, cellulose, paper, textiles, leather and wood.

Although the prior art discloses the specified imidazoyl ketone as an antimycotic agent, and its . use in pharmaceutical formulations, particularly in hair and skin treating compositions, there is no disclosure of its use in dental preparations nor its effectiveness against the specific gram negative anaerobic organisms associated with gingivitis and . periodontitis.

It has now been found that the water insoluble imidazoyl ketone, 1-imidazoyl-l-(p-chlorophenoxy)-3, 3-dimethyl 2-butanone, is selectively effective against the specific anaerobic gram negative . organisms associated with gingivitis, when topically applied to the affected gingiva.

Thus, according to the present invention there is provided an oral composition (as defined herein) for treating gingivitis and periodontitis comprises an oral vehicle and an effective amount of the water insoluble antigingivitis agent, - 7 1-imidazoyI-1-(p-chlorophenoxy)-3,3-dimethy1 2-butanone, solubilised in an nonionic compound, the weight ratio of nonionic compound to antigingivitis agent being in the range 3:1 to 25:1.

The term oral composition used herein means a mouthwash, mouthrinses, chewing gums, tooth powders, toothpastes and dental creams and gels.

The ratio of nonionic solubiliser to imidazole compound is 3:1 to 25:1. At ratios above 25:1, gelation occurs.

According to one aspect of the present invention an oral composition for controlling gingivitis comprises an oral vehicle and an effci Live amount ol the water insoluble antigingivitis agent, 1-inndazoyl-l-(p-chlorophenoxy)-3,3-dimethyl 2- butanone solubilised in a nonionic compound containing about 10 to 80¾ by weight of hydrophilic units of polyoxyethylene per molecule when the hydrophobic radical is polyoxypropylene, the polyoxyethylene radical being of sufficient length to solubilise the said imidazoyl compound in aqueous medium.

From another aspect, the present invention relates to oral compositions comprising about 0.1 to 5¾ by weight of the said anti(|ingivitis agent solubilised in an aqueous oral vehicle comprising a non ionic compound containing a hydrophobic radical which may be for example a higher fatty acid radical containing from 10 Lo 20 carbon atoms, polyoxypropylene, a hexitan mono-higher fatty acid ester, or a fatty acid amide; and a hydrophilic group, for example polyoxyethylene, of sufficient length to effect solubilization. The oral vehicle may be liquid such as a mouthwash or rinse, a solid such as a chewing gum, or A mouthwash preferably has a pH of about 5 to 7.5 and may be an aqueous-alcohol vehicle containing about 1-5¾ by weight of a nonionic surfactant selected from the group consisting of mixed polymers of propylene oxide and ethylene oxide, polyoxyethylene hexitan mono-higher fatty acid esters containing 10-80 moles of ethylene oxide per mol, and higher fatty acid mono- and di-elrtanolamides and mixtures thereof.

The nonionic surfactant preferably contains at least 10-80% hydrophilic units of polyoxyethylene per molecule when the hydrophobic radical is polyoxypropylene. - 8 The preferred ratio of hydrophilic groups to hydrophobic qroups is 4:1 with a molecular weight of about 3250 being preferred, in these mixed polyners of;prnpylene oxide and ethylene oxide.

A toothpaste, which also preferably has a pH of about 5-7.5 comprises a dentally acceptable polishing material, and a liquid vehicle containing water and about 20-40% by weight of a nonionic humectant including at least one humectant selected from the group consisting of polyethylene glycol and polypropylene glycol. Glycerine, sorbitol or mannitol may be substituted for part of the humectant content provided the said antigingivitis agent has been solubilized.

The antigingivitis agent utilized in the present invention is l-imidazoyl-(p-chlorophenoxy)-3^3-dimethy 1 2-butanone having the structural formula: which is prepared by reacting l-bromo-l-(4-chlorophenoxy)-3,3-dimethyl-2-butanone with imidazole dissolved in acetonitrile as disclosed in U.S. . - 9 Patent Nos. 3,812,142 and 3,903,287, which is made a part of this specification. Example 3 of each of USP 3812142 and USP 3903287 describes the production of this compound as follows: · A charge of 15.25 g (0.05 mol) of l-bromo-l-(4’chlorophenoxy)-3,3-dimcthylbutan-2-one and 12 g (0.18 mol) of imidazole is dissolved in 120 ml of acetonitrile and the solution is heated at reflux for 18 hours. After distilling off the solvent in · vacuo, the residue is treated with 150 ml of water and the aqueous phase is thereafter treated three more times with 30 ml of water at a time and dried, and the solvent is distilled off in vacuo. After recrystallization of the residue from about 400 ml . of ligroin, 10.5 g (72% theory) of 1-imidazolyl-l(4'-chlorophenoxy)-3,3-dimethylbutan - 2 - one of melting point 135°C are obtained.

This imidazoyl ketone is a water insoluble crystalline powder having a melting point of 2θ· 94.5-97.8°C which may be obtained from the Bayer Company as Climbazole. Vue to the water insolubility of this imidazole compound, it must first be solubilized in a nonionic compound prior to the addition of ionic materials in an aqueous medium. . it has been unexpectedly found that this antibacterial compound added to oral vehicles is not only effective against the specific anaerobic organisms involved in periodontal disease, but also reduces the disease significantly when applied . topically, as well as reduces the symptoms of - 10 5. gingivitis associated with periodontitis. The minimum inhibitory concentration (MIC) needed to kill Bacteroides assaccharolyticus (Forsyth strain), determined according to the procedure of Walker et al (Antimicrobial and Chemotherapy, Vol. 16, p.452457, 1979), is between 7.8 to 31.2 micrograms per ml. The MIC value for B. gingivalis is 25 micrograms per ral. The MIC value for B. gracilis and Fusobacterium, other gram negative organisms Is greater than 50 for each; and the MIC value for the gram positive organism Actinoymyces viscosus is 125 for the aerobic strain and 250 for the anaerobic strain. This is clearly indicative of the selectivity of the antibacterial activity of the specific imidazole compound utilized herein as the antigingivitis agent.

Evaluation of oral compositions against gingivitis, using a 0.3% Climbazole-containing mouth rinse, made in a study on 30 beagle dogs for 10 weeks, clearly shows its superior effectiveness against gingivitis. The procedure used includes the complete removal of hard and soft dental deposits, after which the dogs are kept on a soft diet for six weeks to permit the development of gingivitis. The dentitions are then treated with the test solutions twice a day, 5 days a week, for about 15 seconds on each side of the mouth. The animals are examined and the degree of inflammation of the gingiva is scored according to a scale of 0 to 3. 0 - No inflammation. 1 - Mild, localized edema, and - II redness of the gingival margin, no bleeding being elicited upon gentle finger pressure. 2 - Moderate edema, and redness of the gingival margin with bleeding upon gentle finger pressure. 3 - Severe edma and ulceration of gingival margin and attached gingiva, and bleeding without gentle finger pressure. A placebo rinse and 0.5% metronidazole rinse were used as the negative and the positive controls respectfully. The data is summarized in - Table 1.

Table 1 Treatment Ratings : Initial gingival units ϋ'Τ 2 6 weeks 10 weeks 3 0 1 nr 3 0 1 3 Placebo Rinse 9 583 8 - - 569 31 - - 528 72 - 0.5'% Metronidazole Rinse 13 578 9 - - 572 28 - - 576 24 - 0.3% Clirnbazole 11 589 - - 579 21 - - 578 22 - Compared to the placebo, both Metronidazole and Climbazole rinses significantly reduced the development of the gingival units of 2. However, a smaller amount (0.3%) of Climbazole exhibits the same effectiveness against gingivitis than greater amounts (0.5%) of Metronidazole.

However, although metronidazole is effective against the specific gram negative micro-organisms involved in periodontal disease when used systemically, as fully discussed prior art, it does not work as well when topically applied. The reason for the said poor results is thought to be due to the absence in its structural formula of an appropriate hydrophobic group which is thought to be necessary for penetration into the gingival tissues. In comparison, Climbazole has a bulky hydrophobic group, (p-chlorophenoxy)-3,3-dimethyl 2-butanone, which provides good penetration into the tissues where the destructive process of periodontitis 1θ· occurs, enabling this antibacterial to maintain an effective concentration to reduce the bacterial count of the gram negative anaerobic micro-organisms associated with this disease. In addition, metronidazole is, due to its nitro group, mutagenic, . whereas Climbazole is not mutagenic in mutagenic tests, because it lacks the nitro group as can be seen by the structural formulae below: Climbazole Metronidazole The oral composition of this invention may be a liquid such as a mouthwash or rinse. In such a preparation the vehicle is typically a water-alcohol mixture. Generally, the ratio of water to alcohol Is in the range of from about 1:1 to about 20:1 . preferably from 3:1 to 20:1, by weight. The alcohol - 13 content preferably constitutes about 20-40% by weight of the vehicle. The total amount of wateralcohol mixture in this type of preparation is typically in the range of from about 70 to about 98% . by weight of the preparation. The pH of such liquid and other preparations of the present invention is preferably in the range of from about 5 to about 7.5.

A preferred component of the liquid oral preparations is about 1-5% by weight of a nonionic . surfactant containing sufficient hydrophilic units e.g. polyoxyethylene reacted with hydrophobic units polyoxypropylene or higher fatty acid, fatty ester or fatty amide in order to solubilize the water insoluble Climbazole in the aqueous-alcohol vehicle.

. Suitable nonionic surfactants include mixed propylene oxide ethylene oxide polymers, polyoxyethylene hexitan . mono-higher fatty acid esters having from 10-20 carbon atoms in the higher fatty acyl thereof and 4-100, preferably 10-80 mols of ethylene oxide per mol. Preferably, the hexitan is sorbitan, although mannitan and other hexitans are also often useful, . the higher fatty acyl is preferably of 10-16 or 20 carbon atoms, more preferably of 12-16 or 18 carbon atoms and most preferably of about 12 carbon atoms, and the number of ethoxy groups is preferably from 15-80, often preferably about 20. Especially useful . is an t.C.1. product sold under the tradename Tween - 14 20, also known as Polysorbate 20 which is polyoxyethylene (20) sorbitan monolaurate.

Similarly useful products are sold under similar identifications, such as Tweens 40, 60, 65 and 80, . all of which are nonionic surface active agents wherein the higher fatty acyl group is palmitoyl, stearoyl or oleyoyl and the number of the mols of ethylene oxide per mol is about 20. However, of these materials the polyoxyethylene sorbitan mono10. laurate Is usually favoured. Polyoxyethylene (80) sorbitan monolaurate may be used in place of said polysorbate 20.

Other suitable nonionic surfactants include the mono- and di-ethanolamides of higher fatty acids . having about 10-18 carbon atoms in the acyl group such as cocomonoethanolaraide, cocodiethanolamide, lauric myristic diethanolamide, lauric raonoethanolaraide or combinations thereof.

The oral compositions of the present invention . may be substantially pasty In character, such as a toothpaste or dental cream. The vehicle of such pasty oral preparations preferably contains polishing material. Examples of polishing materials are water insoluble sodium metaphosphate, potassium . metaphosphate, tricalcium phosphate, calcium pyrophosphate, magnesium ortho-phosphate, trimagnesium phosphate, calcium carbonate, alumina, hydrated alumina, aluminium silicate, zirconium silicates, silica bentonite, crystalline silica . having particle sizes of up to 5 microns, silica - 15 gel, complex amorphorus alkali metal aluminosilicate, hydrated alumina, dicalciura phosphate, and mixtures thereof.

When visually clear gels are employed, a . colloidal silica, such as those sold under the trade mark SYLOID as Syloid 72 and Syloid 74 or under the trademark SANTOCEL as Santocel 100 or an alkali metal aluminosilicate complex is particularly useful as the polishing agent, since they have refractive . indices close to the refractive indices of gelling agent’-liquid (including water and/or humectant) systems commonly used in dentifrices.

The polishing material will generally be present in amounts ranging from about 10 to about 99¾ by . weight of the oral preparation. Preferably, it is present in amounts ranging from about 10 to about 75¾ in toothpaste.

In a toothpaste, the liquid vehicle comprises water and humectant typically in an amount ranging . from about 10 to about 90¾ by weight of the preparation. An essential component of the toothpaste and dental cream is about 20-40¾ by weight of a nonionic humectant including at least one humectant selected from the group consisting of polyethylene glycol and . polypropylene glycol in order to solubilize the water Insoluble Climbazole in the aqueous vehicle. Glycerine, sorbitol or mannitol may be substituted for part of the humectant content, provided the said imidazole compound is solubilized in the polyoxy30. ethylene or polyoxypropylene glycol* - 16 A gelling agent, such as natural or synthetic gums or gum-like materials, typically Irish moss, . sodium carboxymethylcellulose, methyl cellulose, hydroxyethyl cellulose, gum tragacanth, polyvinylpyrrolidone, starch and hydroxypropyl methyl cellulose is usually present in toothpaste in an amount up to about 1% by weight, preferbaly in the range of . from about 0.5 to about 5%. In a toothpaste or gel, the liquids and solids are proportioned to form a creamy or gelled mass which is extrudable from a pressurized container or from a collapsible, e.g. aluminium or lead, tube.

. The oral compositions of this invention may contain a non-soap synthetic sufficiently water soluble organic anionic or nonionic surfactant in concentrations generally ranging from about 1-5 weight percent, to promote wetting, detersive and . foaming properties. U.S. Patent No. 4,041,149 discloses such suitable anionic surfactants in col,4, lines 31-38, and such suitable nonionic surfactants in col.8, lines 30-68 and col.9, lines 1-12, which passages are incorporated herein by . reference thereto.

Thus, suitable anionic surfactants include, for example, the water-soluble salts of higher fatty acid monoglyceride monosulphate detergents (e.g. sodium coconut fatty acid monoglyceride mono30. sulphate), higher alkyl sulphates (e.g. sodium - 17 lauryl sulphate), alkyl aryl sulphonates (e.g. sodium dodecyl benzene sulphonate), higher fatty acid esters of 1,2-dihydroxypropanesulphonate and the like.

. Suitable nonionic organic surface active compounds include water-soluble products which are derived from the condensation of an alkylene oxide or equivalent reactant and a reactive-hydrogen hydrophobe. The hydrophobic organic compounds may . he aliphatic, aromatic or heterocyclic, although the first two classes are preferred. The preferred types of hydrophobes are higher aliphatic alcohols and alkyl phenols, although others may be used such as carboxylic acids, carboxamides, sulphoaraides, . etc. The ethylene oxide condensates with higheralkyl phenols represent a preferred class of nonionic compounds. Usually the hydrophobic moiety should contain at least about 8 carbon atoms, and may contain as many as about 50 carbon atoms or . more. The amount of alkylene oxide will vary considerably, depending upon the hydrophobe, but as a general guide and rule, at least about 5 moles of alkylene oxide per mole of hydrophobe should be used. The upper limit of alkylene oxide will vary . also, but no particular criticality can be ascribed thereto. As much as 200 or more moles of alkylene oxide per mole of hydrophobe may be employed. While ethylene oxide is the preferred and predominating oxyalkylating reagent, other lower alkylene oxides . such as propylene oxide, butylene oxide, and the - 18 like, may also be used or substituted in part for the ethylene oxide. Other nonionic compounds which are suitable are the polyoxyalkylene esters of the organic acids such as the higher fatty acids, the . rosin acids, tall oil acids, acids from petroleum oxidation products, etc. These esters will usually contain from about 10 to about 22 carbon atoms in the acid moiety and from about 12 to about 30 moles of ethylene oxide or its equivalent.

. Still other nonionic surfactants are the alkylene oxide condensates with the higher fatty acid amides. The fatty acid group will generally contain from about 8 to about 22 carbon atoms and this will be condensed with about 10 to about 50 . moles of ethylene oxide as the preferred illustration. The corresponding carboxamides and sulphonaraides may also be used as substantial equivalents .

Still another class of nonionic products are the . oxyalkylated higher aliphatic alcohols. The fatty alcohols should contain at least 6 carbon atoms, and preferably at least about 8 carbon atoms. The most preferred alcohols are lauryl, myristyl, cetyl, stearyl and oleyl alcohols and the said alcohols . should be condensed with at least about 6 moles of ethylene oxide, and preferably about 10 to 30 moles of ethylene oxide. A typical nonionic product is oleyl alcohol condensed with 15 moles of ethylene oxide.

. Pluronic (Registered Trade Mark) type nonionic - 19 surfactants (polyoxyethylene polyoxypropylene block polymers) such as Pluronic F108 and F127 may also be employed.

The antibacterial-containing oral compositions . of the present invention may optionally contain a fluorine-providing compound including inorganic fluoride salts, such as soluble alkali metal, alkaline earth metal and heavy metal salts, for example, sodium fluoride, potassium fluoride, . ammonium fluoride, calcium fluoride, a copper fluoride such as cuprous fluoride, zinc fluoride, a tin fluoride such as stannic fluoride or stannous chlorofluoride, barium fluoride, sodium fluorosilicate, ammonium fluorosilicate, sodium fluoro15. zirconate, sodium monofluorophosphate, aluminium mono- and di-fluorophosphate, and fluorinated sodium calcium pyrophosphate. Alkali metal and tin fluorides, such as sodium and stannous fluorides, sodium monofluorophosphate and mixtures thereof, are . preferred.

The amount of the fluorine-providing compound is dependent to some extent upon the type of compound, its solubility, and the type or oral preparation, but it must be a nontoxic amount. In a solid oral . preparation, such as toothpaste or chewing gum, an amount of such compound which releases a maximum of about 1% fluoride Ion by weight of the preparation is considered satisfactory. Any suitable minimum amount of such compound may be used, but it is . preferable to employ sufficient compound to release - 20 about 0.005 to 1%, and preferably about 0.1% of fluoride Ion. Typically, in the cases of alkali metal fluorides and stannous fluoride, this component is present in an amount up to about 2% by - weight, based on the weight of the preparation, and preferably in the range of about 0.05 to 1%. In the case of sodium monofluorophosphate, the compound may be present in an amount up to 7.6% by weight, more typically about 0.76%.

. Various other materials may be incorporated in the oral preparations of this invention which do not adversely affect the properties of the composition, such as sweetening agents (e.g. saccharin, sucrose, lactose, maltose, sorbitol, etc.); flavouring oils . (e.g. oils of spearmint, peppermint, Wintergreen, sassafras, clove, sage, eucalyptus, marjoram, cinnamon, lemon, orange, etc.), colouring or whitening agents (e.g. titanium dioxide), preservatives (e.g. sodium benzoate) and . the like. Minor amounts, up to about 5% in total, and preferably 0.01 to 3% by weight of these materials may be added to the oral composition.

The present oral compositions are readily prepared by simple mixing methods from readily . available components. However, it is essential that the imidazoyl compound be first mixed with the nonionic component prior to its addition to the oral vehicle which typically includes water.

For instance, a mouthrinse or mouthwash may be . prepared by first solubilizing the imidazole - 21 compound by emulsifying in a nonionic surfactant prior to addition to the aqueous or alcoholic aqueous vehicle. The other ingredients such as flavour, sweetener, etc. may be added to the aqueous . vehicle either prior to or subsequent to the addition of the solubilized imidazole to the aqueous vehicle.

The toothpaste may be prepared by first mixing the imidazole compound with the humectant which is . nonionic, wherein it is solubilized, and then adding the thickener such as carboxymethyl cellulose to form a gel, followed by the addition of polishing agent, water and other ingredients. The sequence of the addition of the various ingredients can be . varied, provided the imidazole compound is first solubilized in the nonionic humectant prior to addition to the water component.

In the practice of this invention an oral composition according to this invention such as a . mouthwash or toothpaste containing 1-imidazoyl-l(p-chlorophenoxy)-3,3-diraethyl 2-butanone antigingivitis agent in an amount effective to promote oral hygiene, is applied regularly to dental enamel, preferably from about 1 to about 3 times daily at a . pH of about 5 to about 7.5.

The present invention may be put into practice in various ways and a number of specific embodiments will be described to illustrate the invention with reference to the following examples. All amounts . and proportions referred to herein are by weight unless otherwise indicated. - 22 5.

EXAMPLE 1 A mouthrinse is made up with the Ingredients and proportions set out in Table 2 below.

Ingredient Alcohol Climbazole Flavour (K.-91-3863) Pluronic F108(l) Glycerine Sodium Saccharin Water to make Note on Table 2 TABLE 2 Composition (% by weight) 0.3 0.22 3.0 0.03 100 (1)Block polymer of 80¾ polyoxyethylene and 20% polyoxyprop.ylenfe with a molecular weight of 3250, obtained from BASF Wyandotte Company.

The Climbazole is mixed with Pluronic until homo geneous and clear, prior to addition to the aqueousalcoholic vehicle containing glycerin, flavour and sodium saccharin.

The resultant product is effective in controlling gingivitis and treating periodontitis, and provides a simple means of improving oral hygiene, when used on a regular regime of 1 to 3 applications to the oral cavity per day.

The unexpected superior antigingival activity of this product is shown In Table 1, wherein the mouthrinse of Example 1 was used as the test solution. This product also possesses antibacterial properties against Bacteroides assaccharolyticus and B. gingivalis I - 23 EXAMPLE 2 A dental paste is made up with the ingredients and proportions shown in Table 3 below.

TABLE 3 . Ingredients Percent Grams H2O 31.3 156.5 Na - Benzoate 0.5 2.5 Na - Saccharin 0.2 1.0 Polyethylene glycol 6Οθ(Ό 25.0 125 10. Climbazole 1.0 5.0 Carboxymethyl cellulose 1.5 7.5 Syloid-244(2) 3.0 15.0 Zeo-490) 35.0 175 Sodium lauryl sulphate 1.5 7.5 15. Flavour Notes on Table 3 1.0 5.0 (1) H(OCH2CH2)nOH where n is an integer between -14, preferably 12.5 to 14 and having a mol weight of 570-630. . (2) Colloidal silica (3) Sodium aluminosilicate (silica with 1¾ combined alumina) by Huber Co.

The Climbazole is premixed with the polyethylene glycol prior to the addition of the carboxymethyl . cellulose, whereby a gel is formed. To this gel is added, with agitation, the Syloid, Zeo, sodium lauryl sulphate, flavour, water, benzoate and saccharin. The benzoate and saccharin may be dissolved in the water prior to mixing with the rest . of the ingredients. Similarly, the Zeo, flavour and - 24 5. sodium lauryl sulphate may be premised prior to addition to the gel.

This product also possesses similarly good antimicrobial and antigingivitis properties.

Other conventional components may be substituted or added, as disclosed hereinbefore. For example, hydrated alumina or water insoluble metaphosphate or dicalcium phosphate dihydrate and other polishing agents may be substituted for the alkali metal aluminosilicate (Zeo) or the colloidal silica (Syloid) in total or in part. Similarly, other nonionic surfactants may be substituted for the block polymer of ethylene oxide (Pluronic) such as the polyoxyethylene hexitan mono-higher fatty acid esters .

Claims (7)

1. An oral composition (as defined herein) for treating gingivitis and periodontitis comprising an oral vehicle and an effective amount of the water insoluble antigingivitis agent, lrinndazoyl-l-(p-ch1orophenoxy)“ 3,3-dimethyl 2-butanone, solubilised in a nonionic compound, the weight ratio of nonionic compound to antigingivitis agent being in the range 3:1 to 25:1.

2. An oral composition as claimed in Claim 1, which contains about 0.1-5¾ by weight of the said antigingivitis agent based on the weight of the composition, the said antigingivitis agent being solubilised in the aqueous oral vehicle comprising a nonionic compound containing about 10-80% by weight of hydrophilic units of polyoxyethylene per molecule when the hydrophobic radical is polyoxypropylene, the polyoxyethylene radical being sufficient length to effect solubilization.

3. An oral composition as claimed in Claim 1, in which the water insoluble antigingivitis agent is solubilised in a nonionic compound containing a mixture of hydrophilic and hydrophobic radicals, the hydrophilic radicals being of sufficient length to effect solubilization in an aqueous vehicle, the weight ratio of hydrophilic:hydrophobic radicals in the nonionic compound being about 4:1.

4. An oral composition as claimed in Claim 1, 2 or 3 which is a mouthwash having a pH of about 5 to 7.5 and comprises an aqueous-alcohol vehicle containing about 1 to 5% by weight of a nonionic surfactant selected from the group consisting of mixed polymers of propylene oxide and ethylene oxide and polyoxyethylene hexitan mono-Cjp-C^Q fatty acid esters containing 10-80 moles of ethylene oxide per mol, and mixtures thereof.

5. An oral composition as claimed in Claim 1, which is a toothpaste having a pH of about 5-7.5 containing a dentally acceptable polishing material, and a liquid vehicle comprising water, and about 20-40% by weight of a nonionic humectant including at least one humectant selected from the group consisting of polyethylene glycol, and polyproplene glycol. - 26

6. An oral composition as claimed in Claim 5 in which glycerin, sorbitol or mannitol is substituted for part of the humectant content, provided that the said antigingivitis agent has been solubilised.

7. An oral composition as claimed in Claim 1 substantially as specifically described herein with reference to the accompanying examples.