COMPOSITIONS AND METHODS FOR INHIBITING PLAQUE FORMATION

Abstract: A dentifrice composition which inhibits plaque formation over an extended period of time. Said composition contains an effective amount of plaque-inhibiting quaternary organosiloxane of the formula (FORMULA) wherein R<s1>s is a alkoxy group having from 1 to 5 carbon atoms. R<s2>s is an alkylene group having from 1 to 25 carbon atoms and R<s3>s R<s4>s and R<s5>s are, individually, alkyl groups of from 1 to 25 carbon atoms, and X is an anion and iodine.

Description: DESCRIPTION * Compositions and Methods for Inhibiting Plaque Formation Technical Field This invention relates to compositions and methods useful in inhibiting the growth of cariogenic bacteria and the formation of plaque on teeth in an oral environment. The prevention of the formation of dental plaque is a highly desired result. Dental plaque results vhen cariogenic bacteria (e.g., Streptococcus utans) collect in colonies on the surface of teeth and form a tenacious deposit thereon. The presence of both the bacteria and the deposits is extremely detrimental to the health of the teeth because if the bacteria and plaque formation are not checked they may result in infected gingival tissue, the forma'tion of dental caries and periodontal disease. In extreme cases they may ultimately result in the loss of teeth. Background Art Many attempts have been made to control cariogenic bacteria and plaque formation on teeth. For example, treatment with fluoride solutions or gels have been used to render the tooth enamel more resistant to the acid action caused by plaque. J These treatments are typically performed in a dental office at periodic, but not frequent, intervals. Such treatments do not, however, result in plaque control for an extended period. Even when the frequency of application of such treatments is increased only partial control has been shown. For example, studies wherein a fluoride-containing solution {1% fluoride concentration) was applied four to five times in the course of a year demonstrated only limited success due to the rapid re- establishment of plaque in the oral cavity. Additionally, the daily application of a fluoride gel by means of a custom-fitted vinyl mouthpiece for a period of twenty-one months showed no substantial change in plaque formation among treated and un- Λ treated patients. See "Clinical Anicaries Effect of Repeated Topical Sodium Fluoride Application by Mouthpiece", Journal of the American Dental Association, V. 75, No. 3, September, 19β7, pp. 638-61.U. Other attempts at inhibiting the formation of plaque have also been made. For example, U.S. Pat. No. 3,733,399 describes toothpaste compositions which contain the enzyme invertase as the active ingredient. Another approach is disclosed in U.S. Pat. No. 3,89 ,li7 wherein the application to teeth of a • dialkyl pyrophosphate having from about 8 to k carbon atoms in the alkyl groups is described as useful in inhibiting plaque formation. However, these approaches require frequent (e.g., daily) use, in order to effectively control the cariogenic bacteria and inhibit the formation bf plaque over an extended period of time. Disclosure of Invention In accordance with the present invention there is provided a dentifrice composition which contains a quaternary ammonium organosiloxane having the formula _ wherein R is an alkoxy group having from 1 to 5 carbon atoms, . R is an alkylene group having from 1 to 25 carbon atoms, and R 3, R k and R5 are, individually, alkyl groups of from 1 to 25 carbon atoms, and X is an anion, preferably selected from chlorine, bromine, fluorine and iodine. Preferably, composi- tions of the invention contain at least about 0.05 by weight, OΛiPI A * vvipo ' and most preferably from about 0.25$ to 1% by weight, of the quaternary ammonium organosiloxane. In another embodiment of the present fnvention there is provided a method for inhibiting plaque formation which com- prises contacting teeth with an effective amount of the above- described, composition. As it is used throughout this specification the term "dentifrice" refers to compositions for topical application to the teeth. Representative of such compositions are outh- washes or rinses, toothpastes, toothpowders, gels, etc. The present invention provides compositions and processes which are useful in controlling cariogenic bacteria and in¬ hibiting the formation of plaque over an extended period of - time despite relatively infrequent application of the compo- sitions to teeth. Best Mode for Carrying Out the Invention The dentifrice compositions of the invention may be applied to the teeth by techniques such as painting or brushing, spraying, bathing and rinsing. Other means of application are also possible and will be. obvious to those in the art as a result of this disclosure. After application to the teeth it is preferred that a short period of time (e.g., one minute) pass before the user eats or drinks. The organosiloxanes useful in the present invention are known materials that may be prepared by simply agitating a warm mixture 1 2 1 2 and an appropriate silane (e.g., [R ] -Si-R X where R , R and X are as described above). In the present invention it is preferred that R be a 2 methoxy group (i.e., CH 0-); R be an alkylene group having 1 to 10 carbon atoms (most preferably a prop^lene group, i.e., -CH -CH -CH -); R be an alkyl group having from 10 to 20 OMPI - It - carbon atoms (most preferably an octadecyl group, i.e., C. Q H__) l 5 lo 37 • R and R each be methyl groups (i.e., CH -) and. X be chlorine. Thus, the most preferred siloxane may be represented by the formula: This compound may also be referred to as 3-(trimethoxysilyl)- propyl-dimethyloctadeeyl ammonium chloride. It may be obtained from Dow Corning Corporation as " 9-5700" as a 0$ by weight solution of the siloxane in methanol. When provided in solution form, dentifrices of the present invention typically comprise a solution of the organosiloxane in water or a mixture of water and an alcohol. Typically the alcohol is a lower, non-toxic alkanol (e.g., ethanol, propanol, etc.). Liquid solutions of the siloxane are particularly use- ful in mouthwashes or rinses. A variety of other ingredients may be added to the denti¬ frices of the present invention. Thus, for example, prophy¬ lactic agents (e.g., supplemental caries-preventing aids) may be included. Moreover, polishing agents, soaps or detergents, flavoring and sweetening agents, thickening agents and humec- tants may also be included. Preferably these other ingredients are free from polyvalent metal such as calcium and magnesium. Representative of suitable prophylactic agents are sodium fluoride, stannous fluoride, potassium fluoride, hexylamine hydrofluoride, myristylamine hydro luoride, betaine fluoride, glycine potassium fluoride, etc. A particularly preferred pro¬ phylactic agent is sodium fluorine. Typically the fluoride prophylactic agents are present in sufficient concentration so as to provide an available fluoride ion concentration of up to about 2% by weight, and preferably in the range of about 0.5-2$ by weight, of the dentifrice composition. Representative of suitable polishing agents are abrasive O - materials such as insoluble condensed phosphates such as calcium pyrophosphate, insoluble calcium polyphosphate (also known as . calcium polymetaphosphate) and highly polymerized sodium poly¬ phosphate (also known as sodium polymetaphosphate); and water- impervious cross-linked thermosetting resins such as the conden- sation products of melamine and urea with formaldehyde. Other suitable polishing agents will be obvious to those skilled in the art as a result of this disclosure. Preferably the polishing agent is not so abrasive so as to scratch or unduly abrade the tooth surface or the dentin. Rather it only cleans the tooth surface. The polishing agents may comprise up to 95$ by weight of the dentifrice composition. Representative of suitable soaps or detergents are the soaps of high molecular weight fatty acids such as sodium and potas- siu soaps of myristic, stearic palmitic acids and fatty acid mixtures of palm oil and coconut oil. Typical useful synthetic detergents include alkyl sulfates and sulfonates having alkyl groups of rom about 8 to 18 carbon / atoms, such as sodium eauryl- sul ate, the sulfated fatty alcohols derived from coconut oil and palm oil, etc. These materials may comprise up to about 5% by weight of the dentifrice composition. Representative of suitable flavoring and sweetening agents are the oils of wintergreen, peppermint, spearmint, sassafras and anise. Additionally small amounts of sweetening agents such as saccharin, dextrose, levulose, etc. may also be em¬ ployed. These flavoring and sweetening agents may comprise up to about 5% by weight of the dentfifrice composition. Representative of suitable gelling or thickening agents are water-soluble salts of cellulose ethers such as sodium carboxy- methyl cellulose and sodium carboxy methyl hydroxy ethyl cellulose; natural gums such as gum karaya, gum arabic, and gum tragacanth; and colloidal magnesium-aluminum silicate or finely divided silica. Such thickening agents may comprise up to about 5% by weight of the dentifrice composition. Representative of suitable humectants are glycerine, sorbitol, other polyhydric alcohols. The.. umectants may com¬ prise up to about 35$ by weight of the dentifrice composition. Tests which demonstrate the effectiveness of the present 5 invention in inhibiting the growth of plaque were performed on Rhesus Monkeys. The teeth of the monkeys were clinically preconditioned to a plaque-free state by ultrasonic cleaning and subsequent dental prophylaxis using a soft rubber prophy¬ laxis cup and standard pumice-filled prophylaxis paste. The 0 teeth were then treated in various- fashions and the effect of the treatment upon the formation of plaque was observed. The effectiveness of plaque inhibition was measured by means of a plaque index number. Plaque index was determined by applying erythrosine B dye (FD&C Red dye #3, Color Index No. _ 5*i-30) to the teeth. This dye stains plaque but not tooth enamel. The stained plaque was visually observed and assigned a rating number using the following scale. 0 No plaque 0.25 Light plaque covering about l/ of tooth 0 surface 0.5 Light plaque covering about 1/2 of tooth surface 0.75 Light plaque covering about 3 of tooth surface 5 1.0 Light plaque covering entire tooth surface 1.25 Heavy plaque on l/k of tooth surface, light plaque on remainder 1.50 Heavy plaque on 1/2 of tooth surface, light plaque on remainder 0 1-75 Heavy plaque on 3 of tooth surface, light plaque on remainder 2.0 Heavy plaque on entire tooth surface The plaque was observed visually and rated periodically for the duration of the test. The ratings for each monkey were then 5 averaged to obtain the reported plaque index for each monkey. ' BURE OMPI A solution containing 3-(trimethoxysilyl)-propyldimethyloc- tadecylammoniumchloride (" 9-5700") was ^ applied to the upper incisors of the test monkeys. Solution A comprised 50$ "Q9-5700" and 50$ methanol by weight. Solutions B & C each comprised 1$ " 9-5700", 1$ methanol and 98$ deionized water by weight. Different lots of " 9-5700" were employed in Solutions B & C. The untreated teeth of the monkeys served as a control. They received no preventative treatment during the tests. The " 'monkeys were fed twice a day with a diet which en¬ couraged plaque formation. The diet consisted of about 135 (R) (R) grams of Purina^ New World Monkey Chow which had been softened with 200 milliliters of distilled water and to which 118 grams of sugar had been added. The Monkey Chow (^R) is com- mercially available from Ralston Purina Co. and has a guaran¬ teed analysis of Crude protein not less than 25-0$ Crude fat not less than / 5-0$ Crude fiber not more than 3-5$ Added minerals not more than 3.0$ Ash not more than 6.0$ "■■ The ingredients in the Monkey Chow (Dwere ground yellow corn, soybean meal, ground wheat, corn gluten meal, dried skimmed milk, animal fat preserved with BHA, sucrose, brewers' dried yeast, salt, dehydrated alfalfa meal, vitamin B supplement, riboflavin supplement, calcium pantothenate, niacin, choline (source of vitamin D_), vitamin E supplement, iron oxide, iron sulfate, manganese sulfate, calcium iodate, calcium carbonate, dicalcium phosphate, anganous oxide, copper oxide, cobalt carbonate, zinc oxide. The results of the tests are as set forth in the following table: PLAQUE INDEX # OF DAYS TREATED CONTROL M0NKEY# SOLUTION TREATMENT TEST LENGTH TEETH TEETH 1 A 1 1 .270 1.58 2 B 1 11. •35 1.25 3 C 1 12 •50 1.00 c 2 12 .187 1.312 h c 3 12 .281 1Λ31 5 " ' c k 12 .56 1 3 6 c 1 12 1.625 1.75 c 5 9 .312 >2.0 7 c 2 9 •375 • 1.875 TREATMENT 1. On day 1 the solution was brushed onto the teeth with a paint brush and air dried for 2 minutes. There was no further treatment for duration of the test. 2. The teeth were brushed daily ■ wi.th the solution. 3. On day 1 the solution was brushed onto the teeth with a paint brush, air dried for 2 minutes. Thereafter the treated teeth were brushed daily with deionized water. h . On day 1 the solution was brushed onto the teeth with a paint brush, air dried for 2 minutes. Thereafter the treated teeth were brushed daily with a composition of 1$ by weight in deionized water. 5. The teeth were rinsed daily with lcc of the solution. Monkey 6 salivated excessively. Hence the single application of Solution C was rinsed away. However, when Solution C was later applied to the same monkey each day for 9 days it provided effective plaque control. Similar plaque control is achieved when the methanol employed in the solutions is removed or is replaced with a non-toxic alcohol such as ethanol.

Claims: - 9 - CLAIMS 1. A dentifrice composition which contains a quaternary ammonium organosiloxane having the formula wherein R is an alkoxy group having from 1 to 5 carbon atoms-,- R,2~ is an alkylene group having from 1 to 25 carbon atoms and 3 - 5 R , , RR aanndd RR5 aarree,, iinnddiivviidduuaallllyy,, aalllkyl groups of from 1 to 25 carbon atoms, .and X is an anion. 2. A dentifrice composition in accordance with claim 1 wherein X is selected from chlorine, bromine, fluorine and iodine. 3. A dentifrice composition according to claim 2 wherein said composition contains at least about 0.05$ by weight of said quaternary ammonium organosiloxane. A dentifrice composition according to claim 3 wherein R 2 is methoxy, R is an alkylene group having from 1 to 10 3 carbon atoms, R is an alkyl group having from 10 to 20 5 carbon atoms, R and are, individually, methyl groups, and X is chlorine. A dentifrice composition according to claim k wherein R 3 is a propylene group and R is an octadecyl group. 6. The method of inhibiting plaque formation by contacting teeth with an effective amount of a dentifrice composition which contains a quaternary ammonium organosiloxane com¬ pound having the formula wherein R is an alkoxy group having from 1 to 5 carbon 2 atoms, R is an alkylene group having from 1 to 25 carbon atoms, and R 3, R and R5 are, individually, alkyl groups •» of from 1 to 25 carbon atoms, and X is an anion. 7. The method of claim 6 wherein X is selected from chlorine, bromine, fluorine and iodine. 1 2 8. The method of claim wherein R is methoxy, R is an 3 alkylene group having from 1 to 10 carbon atoms, R is k an alkyl group having from 10 to 20 carbon atoms, R and R are, individually, methyl groups, and X is chlo¬ rine. 9- The method of claim 8 wherein R is a propylene group 3 and R is an octadecyl group. 10. The method of claim 6 wherein said teeth are contacted by a composition comprising at least about 0.05$ by weight of said quaternary ammonium organosiloxane compound.

Inventors: ENGLE M, FLEUR L, LUCAS A, WEN R
Applicants: MINNESOTA MINING & MFG, MINNESOTA MINING & MFG CO
Application year: 1978
Main classification: A61K7
IPC codes: A61K8, A61K31, A61P1, A61Q11