MXPA00008200A - Improved dental abrasive - Google Patents

Abstract

Oral compositions, such as oral gels and toothpastes, containing a novel high cleaning, low abrasion silica hydrogel abrasive.

Description

IMPROVED DENTAL ABRASIVE FIELD OF INVENTION This invention relates to dentifrice compositions containing a silica abrasive, which improves oral cleansing with low abrasiveness.

BACKGROUND OF THE INVENTION Synthetically produced silicas play an important role as an ingredient in many of the current toothpaste formulas. Such silicas are non-toxic and relatively safe ingredients which are compatible with other ingredients in toothpaste, including glycerin, sorbitol (or xylitol), thickeners, detergents, dyes and fragrance materials and optionally fluorides and other assets. In addition, the silicas act as an abrasive to clean the teeth, remove plaque and food waste.

As an abrasive or polishing agent, the silicas physically rub the outer surface of the teeth. The scrubbing action removes the organic film (eg, the lens) formed of salivary proteins which cover the teeth and which are known to stain and discolour on food, such as coffee, tea and berries, as well as by tobacco smoke, cationic antibacterials, and chromogenic bacteria. Such physical removal of the stained film is a simple and effective means to remove undesirable surface staining and discoloration which occurs daily. In addition, such physical removal of the film also removes the plaque bacteria on the film surface.

Synthetic silicas include both silica gels and precipitated silicas which are prepared by neutralizing the aqueous silicate solutions with a strong mineral acid. In the preparation of the silica gel, a silica hydrogel is formed which is then typically washed at a low salt content. The washed hydrogel can be milled to the desired size, or it can be dried in another way, finally to the point where its structure no longer changes as a result of shrinkage. When preparing such synthetic silicas, the objective is to obtain abrasives which can provide maximum cleaning (for example the removal of stained film with minimal damage to dental enamel and other oral tissue.) Dental researchers are continually concerned with the Identification of synthetic silicas that meet these objectives.

U.S. Patent No. 4,153,680 and British Patent Application 2,038,303 Both disclose the general use of silica hydrogels or hydrated silica gels as toothpaste polishing agents. U.S. Patent No. 4,632,826 discloses the use of hydrous silica gels in combination with a weakly calcined alumina polisher to form an abrasive system combination. U.S. Patent Nos. 4,943,429, 5,176,899 and 5,270,033 provide lists of alternative polishing agents, such lists include hydrated silica gels.

Despite the descriptions relating to silica hydrogels and other compositions for oral cleansing, there is still a need for additional compositions that provide improved film cleaning, improved removal of plaque and food waste, all with minimal abrasion. of dental enamel and other oral tissue.

SYNTHESIS OF THE INVENTION The present invention relates to dentifrice compositions comprising: (a) an orally acceptable dentifrice vehicle of from about 5 percent to about 95 percent by weight of the dentifrice composition; (b) a silica hydrogel of from about 3 percent to about 30 percent of the dentifrice composition containing from 10 percent to 25 percent water by weight, where: (i) the silica hydrogel is composed of particles from about 2 to about 4 microns, the particles have the properties: (ii) a surface Brunauer, Emmett and Teller (BET) is in the range of 150 to 400 square meters / g of silica; (iii) an oil absorption of less than 100 cmVlOO g of silica; (iv) a pH in a suspension of 5 percent w / w in demineralized and boiled water (free of C02), equal to or greater than 8.5; wherein the dentifrice composition has a radioactive dentin abrasion (RDA) of from 90 to 250, preferably from 95 to about 160, and a film cleaning ratio (PCR) of from about 70 to about 130. surprisingly, even though silica gels in general have been reported as having acidic pH levels (Morton Pader, Oral Hygiene Products Practice, pages 254-255, Marcel Dekker, Inc., New York (1988)) and silica hydrogels (hydrous silica gels) of a smaller miera size and higher pH levels have been reported as having unacceptably low abrasion values (GB 2,038,303A, Table 4, page 9); the silica hydrogel of the present invention which has a pH of at least 8.5, exhibits commercially acceptable RDA abrasion values of at least 90.

The details of the physical measurements and attributes mentioned above are discussed below. All measurement levels and ratios are by weight of the total composition, unless otherwise indicated, such as the case of the film cleaning rate (PCR) and radioactive dentin abrasion (RDA) values. ) which have no unity. Additionally, all measurements are made at 25 ° C, unless otherwise specified.

DETAILED DESCRIPTION OF THE INVENTION By "tooth composition" as used herein, is meant a toothpaste, a dental powder, a prophylaxis paste, a pill, a gum or an oral gel.

By the term "orally acceptable dentifrice vehicle" as used herein means a suitable carrier which can be used to apply the present composition to the oral cavity in an effective and safe manner. The orally acceptable carrier as well as other essential and optional components of the present invention are described in the following paragraphs.

Abrasive Hydrous silica gel or silica hydrogels form the compositions of the present invention are colloidal silica particles bonded together within a three dimensional network which can be characterized as a low density silica gel such as an airgel having a volume larger pore size (up to around 4 cc / g), see the work of Kirk-Othmer Encyclopedia of Chemical Technology, volume 21, pages 1020-1021, by John iley & Sons, from New York (4th edition 1997). Such silicas are preferably characterized as synthetic hydrated amorphous silicas, also known as silicon dioxides or SiO2. In addition, these silicas can be characterized because they have a surface area as characterized by the standard nitrogen absorption method of Branauér, Emett and Teller (BET) in the range of 150-400 mVg. The surface area is determined by the method of nitrogen absorption Branauer, Emmett and Teller as described in the work of Branauer et al., Journal of the American Chemical Society 60, 309 (1938). The measurement of Branauer, Emmett and Teller is carried out using an accelerated surface area and a porosimetry analyzer (ASAP 2400), by Micromeritics Instrument Corporation of Norcross, Georgia 30093. The sample is gassed under vacuum at 350 ° C for a minimum of two hours before the measurement.

The silica hydrogel compositions of the present invention are further characterized as having a low average particle size ranging from about 2 microns to about 4 microns with a standard deviation of less than about 0.5 microns. The average particle size is measured using a Malvern particle size analyzer, Mastersizer S model, from Malvern Instruments, Inc., of Southborough, Massachusetts 01772. Specifically, a helium neon gas laser beam is projected through a transparent cell which contains the silica hydrogel particles suspended in an aqueous solution. The light rays which stick to the particles are scattered through angles which are inversely proportional to the particle size. The photodetector array measures the amount of light at various predetermined angles. The electrical signals proportional to the measured light flow values are then processed by a microcomputer system, against a scattered pattern predicted from theoretical particles as defined by the refractive indexes of the sample and the aqueous dispersant to determine the distribution of particle size of the silica hydrogel.

The silica hydrogel used to form the compositions of the present invention is further differentiated by means of its oil absorption values having oil absorption values of less than 100 cc / lOOg and preferably in the range of from 45 cc / lOOg of silica at 90 cc / lOOg of silica. The oil absorption values are measured by determining the amount of dibutyl phthalate oil absorbed in a fixed amount of silica, when the oil-silica mixtures reach a maximum viscosity. Using a constant-rate specimen, the oil is added to a measured quantity of silica, in grams, in a mixing chamber connected to a torsional force rheometer, such as a Brabender Plastic-Corder Electronic Torsional Rheometer, available from C . Brabender Instruments, Inc., of South Hackensack, New Jersey 07606. The volume of oil added to the maximum viscosity is put into the following equation: oil absorption in quantity of oil in ce x 100 / cc / g of silica weight of silica sample in grams where the amount of oil is the time of addition of the oil in seconds times the delivery rate of the oil specimen in cc / second.

The preparation of the silica hydrogels of the present invention is known in the art, for example, from U.S. Patent No. 4,153,680 and from the United Kingdom of Great Britain Patent Application 2,038,303A, the gels of Hydrous silica being the result of the reaction of an alkaline silicate solution with an SiO2 concentration of about 6 to 20 percent by weight in the presence of a mineral acid, such as sulfuric acid, hydrochloric acid, nitric acid, or phosphoric acid. Sodium or potassium silicate can be used as the alkali silicate with the sodium silicate being preferred. An amount less than the stoichiometric amount of acid is added to the alkali silicate solution until a pH of less than 10 to 11 is reached, a pH of about 8.5 is preferred. The resulting product is a solid silica which includes water within its pores. After the silica hydrogel is formed it is washed with an alkaline pH solution at a pH of at least 8.5 to maintain the high pH of the silica gel, at low temperatures of from about 0 to 60 ° C until that a purity level of about 98 percent Si02 is obtained (the remaining impurity being sodium sulfate). The resulting silica hydrogel is milled at 2 to 4 microns desired in particle size diameter and dried at a water content of from 10 to 25 percent by weight, preferably about 20 percent by weight, to yield the hydrogel of desired silica.

A preferred abrasive silica hydrogel of the present invention is marketed under the trade designation Sylodent XWA300 from the Davison Chemical Division of .R. Grace & Co., of Baltimore, Maryland 21203. The Sylodent X A300 silica hydrogel is composed of colloidal silica particles averaging from about 2 about 4 microns in diameter, which has a BET surface area of from 100 to 200m2 / g of silica, an oil absorption of less than 100cm3 / l00g of silica and a pH higher than 8.5. Commercially available abrasives which can be used in combination with the silica hydrogel, include silicas having an average particle size of up to about 20 microns, such as Zeodent 115, marketed by J.M. Huber Chemicals Division, of Havre de Grade, Maryland 21078 or Sylodent 783 also marketed by Davison Chemical Division of W.R. Grace & Co.

The abrasivity of the dentifrice compositions of the present invention containing the silica hydrogel abrasives described herein, can be determined by means of the RDA values as determined according to the method recommended by the American Dental Association, established by Hefferren, Journal of the Dental Research, Volume 55, Number 4, July-August 1978, pages 563-573 and as described in the United States of America patents of Wason Nos. 4,340,583, 4,420,312 and 4,421,527. In this procedure the extracted human teeth are irradiated with a neutron flux and are subjected to a standard brushing regime. The radioactive phosphorus 32 removed from the dentin in the roots is used as the index of the abrasion of the tested toothpaste. A reference solution containing 10 grams of calcium pyrophosphate in 15 ml of 0.5 percent aqueous solution of sodium carboxymethylcellulose is also measured and the RDA of this mixture is arbitrarily taken as 100. The silica hydrogel toothpaste to be The test is prepared as a suspension at the same concentration as the pyrophosphate and is subjected to the same brushing regime. The RDA of the hydrogel abrasive dentifrice of the present invention is from 250 to 90, preferably from about 160 to about 95.

The film cleaning rate (PCR) of the silica hydrogel compositions of the present invention, a measurement of the cleaning characteristics of the dentifrices, generally ranges from about 70 to 130 and is preferably greater than about 95.

The PCR (cleanliness ratio of film) cleaning values is determined by a film cleaning ratio test generally described in the work "In vitro removal of stain with toothpaste" by G.K. Stookey et al., Journal and Dental Research, Volume 61, pages 1236-9, November 1982. Cleaning is assessed in vitro by staining 10 square millimeters of bovine enamel samples embedded in a resin, which are etched with acid for accelerate the accumulation and adherence of the stain. The spotting is with a broth prepared from instant coffee, instant tea and ground mustard gins finely dissolved in a sterilized trypticase soy broth containing a culture of Sarcina lutea turtox 24 hours. After staining, the specimens are mounted on a V-8 transverse brushing machine equipped with soft nylon toothbrushes adjusted to a tension of 150g on the surface of the enamel. The samples are then brushed with the dentifrice of the present invention and a standard calcium pyrophosphate (lOg of calcium pyrophosphate in 50 ml of an aqueous solution of 0.5 percent sodium carboxymethylcellulose). The specimens are brushed with toothpaste solutions consisting of 25 grams of toothpaste in 40 grams of deionized water, for 400 strokes. The specimens are cleaned with Pennwalt pumice meal until the stain is removed. The reflectance measurements are taken using a Minolta chromameter where a scale of the International Clarity Commission (CIÉ) L "a * b * is used to measure the color of the specimens.The percentage of spot (SR) removed is calculated using the following formula: (b3-b,) 2) 0-5 where L ,, a ,, and b, are reflectance measurements taken before brushing, L2, a2 and b2 are reflectance readings taken after brushing and L3, a3, and b3 are measurements taken after pumice treatment.

The film cleaning ratio is measured as follows: PCR =% SR for sample /% SR for standard calcium phosphate X 100 The silica hydrogel abrasive may be present as the only abrasive within the dentifrice compositions of the present invention or in combination with other known toothpastes or polishing agents. Other useful dentifrice abrasives include sodium metaphosphate, potassium metaphosphate, tricalcium phosphate, dicalcium phosphate dihydrate, aluminum silicate, calcined alumina, bentonite or other siliceous materials or combinations thereof.

The total amount of abrasive of the entire present invention is at a level of from about 5 percent to about 30 percent by weight, preferably from about 8 percent to about 12 percent by weight when the tooth composition is a toothpaste . Higher levels, as high as 95 percent can be used if the tooth composition is a dental powder, Toothpaste Vehicle The orally acceptable dentifrice vehicle used to prepare the dentifrice composition comprises a water phase containing a humectant therein. The humectant is preferably glycerin, sorbitol, xylitol and / or propylene glycol of molecular weight in the range of 200-1000; but other humectants and mixtures thereof may also be employed. The humectant concentration typically makes a total of about 5 to about 70 percent by weight of the oral composition.

The reference herein to sorbitol refers to the material typically commercially available as a 70 percent aqueous solution. Water is typically present in an amount of at least about 10 percent by weight, and generally from about 25 to 70 percent by weight of the oral composition. The water used in the preparation of commercially suitable toothpastes should preferably be deionized and free from organic impurities. These amounts of water include free water which is added plus that which is introduced with other materials such as with sorbitol.

The dentifrice compositions of the present invention may contain a variety of optional tooth ingredients. As described herein, such optional ingredients can include, but are not limited to thickeners or gelling agents, surfactants (eg surface-active agents), a source of fluoride ions, a synthetic anionic polycarboxylate, an agent flavoring, additional antiplaque and / or abrasive agents, and coloring agents.

Thickening agents The thickeners used in the compositions of the present invention include natural and synthetic gums and colloids, examples of which include carrageenan (Irish moss), santan gum and sodium carboxymethylcellulose, polyvinylpyrrolidone, starch, hydroxyethylpropylcellulose, hydroxybutylmethylcellulose, hydroxypropylmethylcellulose, and hydroxytylcellulose. Inorganic thickeners include amorphous silica compounds which function as thickening agents and include colloidal silicas compounds available under the trademarks such as Cab-o-sil Silica Smoke manufactured by Cabot Corporation and distributed by Lenape Chemical, Bound Brokk, New Jersey; Zeodent 165 of J.M. Huber Chemicals Division, Havre de Grade, Maryland 21078; and Sylox 15, also known as Sylodent 15, available from Davison Chemical Division of W.R.

Grace Corporation, of Baltimore, Maryland 21203. The thickening agent is present in the dentifrice composition in amounts of from about 0.1 to about 10 percent by weight, preferably from about 0.5 to about 4 percent by weight.

Surfactants The surfactants are used in the compositions of the present invention to achieve an increased prophylactic action and make the dentifrice compositions more cosmetically acceptable. The surfactant is preferably a detersive material which imparts detersive and foam properties to the composition. Suitable examples of the surfactants are water soluble salts of monoglyceride higher fatty acid monosulfates such as the sodium salt of the monosulfated monoglyceride of hydrogenated coconut oil fatty acids, higher alkyl sulfates such as sodium lauryl sulfate, alkyl aryl sulfonates , such as sodium dodecylbenzene sulfonate, higher alkyl sulfacetates, sodium lauryl sulfacetate, higher fatty acid esters of 1,2-dihydroxypropane sulfonate, and the substantially saturated primary aliphatic acyl amides of lower aliphatic amino carboxylic acid compounds, such as those having from 12 to 16 carbons in the fatty acid, alkyl or acyl radicals, and the like. Examples of the aforementioned amides are N-laurolo sarcosine, and the sodium, potassium, and ethanolamine salts of N-laurolide, N-meristoyl, or N-palmitoyl sarcosine. The surfactant is typically present in the dentifrice compositions of the present invention in an amount of from about 0.3 to about 5 percent by weight, preferably from about 0.5 to about 2 percent by weight.

Fluoride and other active agents The dentifrice composition of the present invention may also contain a source of fluoride ions or a fluorine-providing compound, such as anticaries agent in an amount sufficient to supply about 25 parts per million to 5,000 parts per million of fluoride ions. includes inorganic fluoride salts, such soluble alkali metal salts, for example, sodium fluoride, potassium fluoride, sodium florosilicate, ammonium florosilicate, sodium monoflorophosphate, as well as tin florides, such as floruro-tinose and stannous chloride The florurosódico is preferred.

In addition to the floride compounds, anticalculus agents such as pyrophosphate salts including dicalcalin or tetraalkaline metal pyrophosphate salts such as the long chain phosphates Na4P207 may also be included., Ka4P207, Na2K2P207, Na2H2P207 and K2H2P207 such as sodium exametaphosphate and cyclic phosphates such as sodium trimetaphosphate. These anticalculus agents are included in the dentifrice composition at a concentration of about 1 to about 5 percent by weight. Another active agent useful in the dentifrice compositions of the present invention are the antibacterial agents which may be from 0.2 to 1.0 percent by weight of the composition of the dentifrice. Such useful antibacterial agents include the non-cationic antibacterial agents which are based on phenolic or bisphenolic compounds, such as the halogenated diphenyl ethers such as triclosan (2,4,4'-trichloro-2'-hydroxyphenyl ether), benzoate esters or carbanilides. A preferred antibacterial agent is triclosan, which is a broad spectrum antibacterial agent, marketed for use in oral products under the trademarks Irgacare MP or Irgasan DP300 from Ciba-Geigy Corporation, of Greensboro, North Carolina 27419.

Anionic polycarboxylate The synthetic anionic polycarboxylates can also be used in the dentifrice compositions of the present invention as an efficacy enhancing agent for any anticalculus, antibacterial or other active agent within the dentifrice composition. Such anionic polycarboxylates are generally used in the form of their free acids or partially in a preferable manner or more preferably in complete form the ammonium or alkali metal salts (for example potassium and preferably sodium) soluble in nautralized water. Copolymers of 1: 4 to 4: 1 of maleic acid or anhydride with another polymerizable ethynyl unsaturated monomer, preferably maleic anhydride / methyl vinyl ether having a molecular weight (MW) of from about 30,000 to about 1,800,000 more preferably are preferably preferred. 3,000 to around 700,000. Examples of these copolymers are available from GAF Corporation under the trademark Gantrez, for example AN 139 (M.W. 500,000), AN 199 (M.W. 250,000); S-97 Pharmaceutical Class (M; W 700,000), AN 169 (M.W. 1,200,000-1,800,000), and AN 179 (M.W. above 1,800,000); wherein the petrified copolymer is the pharmaceutical class S-97 (M.W. 700,000).

When present, the anionic polycarboxylates are employed in effective amounts to achieve the desired improvement in efficacy of any anti-jar, antibacterial or other active agent within the tooth composition. Generally, anionic polycarboxylates are present within the dentifrice composition of from about 0.05 percent to about 4 percent by weight, preferably from about 0.5 percent to about 2.5 percent by weight.

Flavor The dentifrice composition of the present invention may also contain a flavoring agent. Flavoring agents which are used in the practice of the present invention include essential oils as well as various flavoring aldehydes, esters, alcohols and similar materials. Examples of essential oils include oils of spearmint, peppermint, pyrol, sassafraz, clove, sage, eucalyptus, marjoram, cinnamon, lemon, lime, grapefruit and orange. Also useful are such chemicals as menthol, carbonand anetole. Of these, the most commonly used are peppermint and peppermint oils.

The flavoring agent is incorporated into the dentifrice composition at a concentration of from about 0.1 to about 5 percent by weight and preferably from about 0.5 to about 1.5 percent by weight.

Other ingredients Various other materials can be incorporated into the dentifrice compositions of this invention, including desensitizers such as potassium nitrate; bleaching agents, such as hydrogen peroxide, calcium peroxide and urea peroxide; condoms, silicones; and the chlorophyll compounds. These additives, when present, are incorporated into the dentifrice composition in amounts which do not adversely affect substantially the desired properties and characteristics.

Preparation of the toothpaste The preparation of dentifrices is well known in the art, as described in US Pat. Nos. 3,996,863, 3,980,767, 4,328,205 and 4,358,437, which are incorporated herein by reference. More specifically, to prepare a dentifrice of the present invention, humectants for example glycerin, sorbitol, propylene glycol and polyethylene glycol are generally dispersed in water in a conventional mixer under agitation. In the dispersion organic thickeners are added, such as carboxymethylcellulose (CMC), carrageenan, or xanthan gum; any anionic polycarboxylate; any salts, such as sodium fluoride, anticaries agents and any sweeteners; The resulting mixture is stirred until a homogeneous gel phase is formed. In the gel phase, a pigment such as Ti02, and any acid or base required to adjust the pH are added. These ingredients are mixed until a homogeneous phase is obtained, after which the polishing / abrasive agent is mixed in the gel phase. The mixture is then transferred to a vacuum / high speed mixer where the inorganic thickener, such as Sylodent 15; and the surfactant ingredients are added to the mixture. Any antibacterial agent insoluble in water, such as triclosan, are solubilized in the flavor oils and the solution is added to the mixture which is combined at high speed for from 5 to 30 minutes, under vacuum from about 20 to 50 millimeters of Hg, preferably of about 30 mm Hg. The resulting product is in each case an extrudable, semi-solid and homogeneous gel or extrudate product.

The following example further describes and demonstrates the preferred embodiments within the scope of the present invention. The example is given only for illustration, and should not be considered as a limitation of this invention since many variations of it are possible without departing from its spirit and scope. EXAMPLE Two hydra silica dentifrice compositions of the present invention designated compositions 1 and 2 in table 1 below were prepared with a total 20 percent abrasive content as described below.

TABLE 1 Toothpaste formulas Compositions 1 and 2 were prepared in a vacuum mixing tank and coated at room temperature. The glycerin and sorbitol humectants were added to the water in the mixing tank and agitation was initiated. Sodium fluoride salt, sodium saccharin sweetener, sodium carboxymethylcellulose organic thickener, and Gantrez S-97 were added and mixing continued until a homogeneous gel phase was obtained. In the gel phase, the pigment Ti02 and the sodium hydroxide were added to adjust the pH. Silica thickener Zeodent 165 was then added to the abrasives, and the resulting mixture was added to the mixing tank under high agitation and at a vacuum of about 30mm Hg. The triclosan was dissolved in the flavor oils to form a solution and the solution was added with the sodium lauryl sulfate surfactant, to the mixing tank while maintaining the vacuum at around 30 mm Hg. Mixing and vacuum continued for approximately 15 minutes. The resulting composition which was an extrudable paste having a pH of about 7 was piped.

The PCRs of composition 1 and 2 were established using the modified Stookey procedure as described above, and the results are recorded in Table II given below. The RDA value of composition 1 was determined by the Hefierren method as described here, and the results are recorded in table II. In addition, for the purposes of comparison, the example procedure was repeated using a dentifrice (designated composition 3) having essentially the same composition; except that in composition 3 the abrasive was an amorphous silica abrasive (silica abrasive Zeodent 115). The PCR and the RDA of the comparative composition 3 is also set forth in Table II, given below.

Table II PCR's of toothpaste formulas Referring to Table II, even when composition 1 contained both the silica hydrogel abrasive of the present invention and the amorphous silica abrasive exhibited a significantly higher PCR (over 39%) than the comparative composition containing only the abrasive of amorphous silica, the RDA value for composition 1 was 107 and that for comparative composition 3 was a relatively low 91, indicating that composition 1 was moderately more abrasive than composition 3 comparative. Composition 2 contained as the only abrasive the silica hydrogel of the present invention, exhibiting a significantly higher PC than both composition 1 and comparative composition 3.

Claims (9)

1. A dentifrice composition comprising: (A) an orally acceptable toothpaste vehicle of from about 5 percent to about 95 percent by weight of the dentifrice composition; Y (B) a silica hydrogel of from about 3 to about 30 percent of the dentifrice composition containing from 10 to 25 percent water by weight, wherein: (i) the silica hydrogel is composed of particles from about 2 to about 4 microns, the particles have the properties: (ii) a BET surface area that is in the range of 150 to 400 m2 / g of silica; (iii) an oil absorption that is less than about 100cm3 / 100g of silica; Y (iv) a pH, in the suspension of 5 percent w / w of the silica in boiled demineralized water (free C02), equal to or greater than 8.5; wherein the dentifrice composition has an RDA of 95 to 160 and a PCR greater than 95.

2. A dentifrice composition as claimed in clause 1 characterized in that said composition further comprises a fluoride ion source.

3. A dentifrice composition as claimed in clause 2 further characterized in that it comprises a surfactant.

. A dentifrice composition as claimed in clause 3 characterized in that said composition has a pH of about 7 and wherein the surfactant is sodium lauryl sulfate.

5. A dentifrice composition as claimed in clause 4 further characterized in that it comprises from about 5 percent to about 70 percent of a humectant selected from glycerin, sorbitol, propylene glycol and mixtures thereof.

6. A dentifrice composition as claimed in clause 1 characterized in that it is in the form of a toothpaste, a powder for the teeth; a prophylaxis paste, a pill, a gum or an oral gel.

7. The dentifrice composition as claimed in clause 1 characterized in that the dentifrice composition comprises an anticalculus agent or an antibacterial agent or mixtures thereof, and an anionic polycarboxylate.

8. A method for reducing the stain and / or plac and inhibiting gingivitis comprising the application of a safe and effective amount of a composition according to clause 1 to teeth and other oral surfaces.

9. A method for reducing stain and / or plaque and inhibiting gingivitis comprising the application of a safe and effective amount of a composition as claimed in clause 2, to teeth and other oral surfaces. E S U M E N Oral compositions such as oral gels and toothpastes, containing a silica abrasive abrasive low abrasion and novel high cleaning.