MXPA97001597A - Economic dental compositions containing aluminosilicatos de sodio novedo - Google Patents

Abstract

The present invention relates to dental compositions comprising an abrasive, a wetting material, water and a binder. The abrasive comprises the sodium aluminosilicate product which has a water demand of more than 50 g of water per 100 g of product and the dental compositions comprise a water to abrasive ratio greater than

Description

THAT'S IT.

ECONOMIC DENTAL COMPOSITIONS CONTAINING NOODILY SODIUM ALUMINOSILICATES FIELD OF THE INVENTION The present invention relates to novel dental compositions containing novel sodium aluminosilicates (SAS), to novel sodium aluminosilicate abrasives and polishing agents, and to processes for the preparation of such products. More particularly, the present invention relates to inexpensive dental compositions having good cleaning ability, whose compositions contain abrasives of sodium aluminosilicates and polishing agents and, to processes for the preparation of such products.

BACKGROUND OF THE INVENTION The toothpastes and current dental formulations can be divided into two main categories: cosmetic types and therapeutic types. The cosmetic types do not contain anti-cavity ingredients such as floride while the therapeutic version, in addition to other active ingredients, contain floride as an anti-caries agent. Toothpastes and dental formulations can also be classified into two les, the classic tooth paste and the paste for high demand and high quality price. The classic toothpaste typically contains an abrasive, a humectant and other ingredients. Typical examples of abrasives used in conventional toothpastes include alumina, dicalcium phosphate dihydrate (DCPD), insoluble sodium metaphosphate (IMP), calcium pyrophosphate, gypsum (calcium carbonate) and compounds released. The classic toothpaste composition typically contains 40-50% of the aforementioned abrasives and about 25% of a humectant such as glycerin and about 25% water. The abrasive, wetting and water system provides a paste for teeth of acceptable quality for the market. A classic toothpaste formula is given in Table I Around 1970 a new class of abrasive system was introduced that imparted transparent or translucent dentifrice properties, although it also required high levels of humectant in the compositions. The abrasive system in high demand toothpaste for moisturizer consisted of precipitated silica or alumina gel. A high demand dentifrice dentifrice composition of high quality price containing the precipitated silica abrasive system is given in Table II.

As can be seen from Table II, the silica abrasive system typically comprises about 20% of the formulation while the wetting system comprises about 65% of the formulation, which results in an approximate weight ratio of humectant to abrasives of silica from 3 to 1. The examination in Table I shows that the ratio of humectant to abrasive in the classical formulation is approximately 0.5. Moisturizers are more expensive and, therefore, toothpastes with high demand for high quality humectant based on silica are more expensive in their manufacture than their conventional counterparts.

Toothpastes, both classic type and high demand versions of high quality moisturizer, are commonly sold in the market. However, there is a significant need in the market for a new, inexpensive generation of toothpaste that requires a low level of humectant and has a very high water content. More particularly, in the Western world, due to the high standard of living, it is very common for toothpaste manufacturers to promote silica based toothpaste with high demand for high quality moisturizer. However, in many parts of the world, especially in countries with a deteriorating economy, there is a strong need for a new generation toothpaste which requires the lowest levels of abrasives compared to classical toothpaste and which has a demand for toothpaste. Higher water and the lower demand for humectant compared with silica based toothpaste resulted in a low cost formula.

BRIEF DESCRIPTION OF THE INVENTION Accordingly, it is an object of the present invention to provide novel dental compositions. It is a more specific object of the invention to provide novel dental compositions that are inexpensive and that simultaneously provide good cleaning power. Additionally, it is an object of the invention to provide dental compositions that have good appearance and good mouth feel and that have good therapeutic qualities. It is a further object to provide dental compositions that have low demand for humectant and low abrasive content and that contain high water contents. It is a related object to provide novel sodium aluminosilicate abrasives that are inexpensively produced and are suitable for use in the preparation of novel dental compositions of the invention. Additionally, it is an object of the present invention to provide sodium aluminosilicate products that have a high water demand and low demand for humectant. It is a further object of the invention to provide sodium aluminosilicate products which are compatible with other components of dental compositions. It is a related object of the invention to provide inexpensive preparation methods of such sodium aluminosilicate compounds.

These * and other additional objects are provided by the present invention in the form of novel dental compositions, novel sodium aluminosilicate products and, processes for the production of such products. More particularly, the dental compositions according to the present invention comprise an abrasive, a wetting material, water and a binder. The abrasive comprises sodium aluminosilicate (SAS) products that have a demand of more than 50 g of water per 100 g of SAS product and the dental compositions comprise a weight ratio of water to abrasive greater than 1. Preferably, the compounds of sodium aluminosilicate of the invention are of the formula Na2O.AI2O3.4XSiO2.YH2O wherein X is from about 2 to about 3.4 and Y is from about 2X to about 3X and, has a water demand of more than about 50g of water per 100 g of SAS product and less than 90 g of water per 100 g of SAS product. It is further preferred that the sodium aluminosilicate product have a humectant demand of less than about 80 g of humectant per 100 g of SAS product.

A process for producing the sodium aluminosilicate products according to the present invention comprises providing an aqueous solution of sodium sulfate and heating the solution, adding the sodium silicate to the aqueous solution and when the pH of the aqueous solution reaches approximately 10.2. , continue the addition of sodium silicate and aluminum to reduce the pH to about 8.4 and then reduce the addition rate of the aluminum to maintain the pH at about 8.5, complete the addition of the sodium silicate and continue after the addition of the aluminum until that the pH reaches approximately 5.9. the precipitated sodium aluminosilicate is allowed to digest to complete the reaction. Accordingly, the sodium aluminosilicate products can be produced inexpensively in accordance with the methods set forth herein.

The dental compositions herein provide a good combination of cleansing ability, therapeutic value, good appearance and good mouth feel. Additionally, due to the low levels of humectant, the low levels of abrasive and the high water levels, the current dental compositions can be provided at a significantly lower cost than those of the classic formulations and high-quality high-humectant.

These and further advantageous objects of the dental compositions, sodium aluminosilicate products and methods of the present invention will be more fully understood in view of the following detailed description.

DETAILED DESCRIPTION Through continuing research, the new generation toothpaste compositions employing a unique sodium aluminosilicate product as an abrasive system have been discovered. The ratio of humectant to abrasive in the present compositions is significantly lower than the ratio present in the high quality wetting silica based dentifrice compositions. Additionally, the ratio of water to abrasive is significantly higher in current compositions compared to classical and high quality compositions. Thus, the new generation abrasive system is remarkable in that it is significantly lower in total system costs compared to the silica based composition and has overcome the disadvantage of the cost limitations of the classic type toothpaste.

The dental compositions according to the present invention preferably comprise an abrasive, a wetting material, water and a binder. The abrasive comprises sodium aluminosilicate products having a water demand of more than 50 g of water per 100 g of product and, the dental compositions comprise a weight ratio of abrasive water greater than 1. In a preferred embodiment, the compositions teeth comprise from about 15 to about 35% by weight of the abrasive, from about 10 to about 25% by weight of the humectant material, from about 35 to about 70% by weight of water and from about 0.1 to 5% by weight of the binder. More preferably, the dental compositions comprise from about 20 to about 30% by weight of the abrasive, from about 15 to about 23% by weight of the wetting material, from 40 to about 60% by weight of water and from about 0.5 to about 2%. by weight of the binder.

The humectant material that is included in the dental compositions of the present invention may be any of the materials known in the art and conventionally employed in dental compositions. In a preferred embodiment, the humectant material is selected from the group consisting of glycerin, sorbitol, xylitol, propylene glycol, corn syrup, glucose and mixtures thereof, with glycerin and sorbitol being particularly preferred.

The binder that is included in the dental compositions of the invention can similarly comprise any materials known in the art and conventionally employed in dental compositions. Preferably the binder is selected from the group comprising alkali metal carboxymethyl celluloses, hydroxyethyl carboxymethyl celluloses, natural and synthetic gums, polyvinyl pyrrolidone, starch, water soluble hydrophilic colloidal carboxylic polymers, seaweed colloids and mixtures thereof. In a preferred embodiment, the binder comprises a carboxymethyl cellulose material.

The dental compositions of the present invention can provide a therapeutic effect by including therein a fluoride-providing compound. In a preferred embodiment, the fluoride-providing compound comprises a monofluorophosphate salt, for example, sodium monofluorophosphate, lithium monofluorophosphate, potassium monofluorophosphate or mixtures thereof, or ammonium monofluorophosphate. The fluoride-providing compound is preferably included in the compositions in an amount from about 0.1 to about 2.0% by weight.

The dental compositions may further include one or more organic surfactants or foaming agents in order to obtain improved distribution of the toothpaste composition during use, to assist in obtaining a complete and complete dispersion of the composition through the oral cavity and to make the compositions more acceptable from the cosmetic point of view. The organic surfactant may be ionic in nature, ampholytic or cationic. Examples of such agents include water soluble salts or monoglyceride monosulfates of higher fatty acids, higher alkyl sulfates, alkyl arylsulfonates, olefin sulphonates, higher alkylsulfoacetates and higher aliphatic acylamides of lower aliphatic aminocarboxylic acid compounds. These surfactants can be used alone or in combination and in a preferred embodiment the total amount of the surfactants included in the compositions comprises from about 0.1 to about 5% by weight.

The dental compositions may further include one or more ingredients including flavoring agents, coloring agents, bleaching agents, preservatives, antibacterial agents and the like. Examples of suitable flavoring ingredients include flavor oils, sweetening agents and the like. Preferably, these additional ingredients may each be included in an amount from about 0.1 to about 2% by weight.

As noted above, the dental compositions according to the present invention comprise a weight ratio of water to abrasive of more than 1. Thus, the compositions contain relatively greater amounts of water and smaller amounts of abrasive and humectant compared to many conventional tooth compositions. The compositions of the invention are therefore significantly less expensive compared to conventional compositions.

Typical formulation costs are shown in Table III wherein the costs of a conventional conventional formulation and a high demand formulation of high quality humectant are set together with the costs of six dental formulations according to the invention. Specifically, the cost calculations for the different formulations were made based on the contents of abrasive, humectant and water, which make up 94 kg per 100 kg of each formulation. The remaining 6 kg of the 100 kg of each formulation is made up of a combination of surfactant, the compound that provides fluoride, flavors, sweeteners and preservatives that are assumed to be the same for each formulation, both in terms of content and cost. Therefore, the cost calculations are based on the 94 kg per 100 kg of each formulation that varies from one formulation to another. In calculating the costs of the various formulations, the following material costs were used in US dollars, per kg of material: Ingredients S / kg DCPD (Abrasive) 1.06 Silica (Abrasive and thickener) 1.17 Aluminosilicate sodium (Invention) 0.88 Glycerin, 96% 1.20 Sorbitol, 70% solution 0.53 PEG 1.34 The cost savings of the formulations according to the present invention, the CH formulations, purchased with the cost of the classical formulation A in Table III are set forth in Table IV. To demonstrate the manner in which the savings were calculated, the savings of cost obtained by the formulation C according to the invention compared to the classical formulation A was calculated as follows- ((7770-51 60) / 7770) x 100 = 336% the water to abrasive ratios for each of the AH formulations in Table III are also set forth in Table IV. To demonstrate the manner in which the water to abrasive ratio is determined, this ratio for formulation F is as follows (weight of water added + weight of water in humectant, if any) / weight of abrasive. (43 kg + (3 x 21 kg)) / 30 kg = 1 6 The amount of water used in the determination of this ratio included both the added water and the water if any in the humectant. Thus, the dental compositions according to the present invention provide significant cost savings. The aluminosilicate products of the present invention are prepared in accordance with the following reaction sequence: AI2 (SO4) 3 + 4 (Na2O.XSiO2)? Na2O.4XSiO2.YH2O + 3Na2SO4 wherein X is from about 2 to about 3.4, more preferably from about 2.6 to about 3.3, and Y is from 2X to 3X. In accordance with the specific procedure of the present invention, an aqueous solution of sodium sulfate is provided in a reactor. Agitation is provided and the aqueous solution is preferably heated. Heating can be maintained throughout the reaction sequence. The heating was carried out suitably at a temperature of at least 60 ° C to about 93.3 ° C, and more preferably at about 76.6 ° -90.5 ° C. therefore, the sodium sulfate solution is preferably heated to a temperature of about 76.6o- 90.5 ° C and maintained at that temperature range throughout the reaction. The reaction is initiated by the addition of sodium silicate to the aqueous solution. Preferably the sodium silicate is added in the form of an aqueous solution and contains a SiO2 / Na2O molar ratio of X as defined above. Once the pH of the aqueous solution reaches approximately 102, the addition of sodium silicate is continued and the addition of alum (AI2 (SO4) 3H2O) is initiated to the aqueous solution. The alum is preferably purified and added in the form of an aqueous solution. In a preferred embodiment, the sodium silicate solution and the alum solution are heated before addition to the aqueous solution in the reaction. For example, the solution of Sodium silicate and the alum solution were heated to a temperature of about 48 8 ° C The additions of sodium silicate and alum are continued until the pH of the aqueous solution is reduced to about 84 The rate of addition of the alum is then reduced in order to maintain the pH of the aqueous solution mixture at about 8 ° C. The addition of the sodium silicate is then completed and the addition of the alum is continued to the aqueous solution until the pH of the solution reaches approximately 59 ° C. that the pH of the aqueous solution is reduced to approximately 5.9, the addition of alum is discontinued The aluminosilcate sodium product precipitates The digested mixture containing a product of sodium aluminosyllate can be filtered and the cake collected from the precipitated sodium aluminosilicate product can be washed to remove the sodium sulfate. In a preferred embodiment, the washed wet cake is then slightly diluted to fluidize the cake and the resulting cake batter is dried, for example, to a moisture content of about 5%. Depending on the final use of the product, the product can be ground to reduce the particle size. For example, when the sodium aluminosilicate product is used in a dental formulation, the dried product is milled to reduce its particle size to an average particle size of about 9 microns as measured using the Microtrac method described in the examples. The sodium silicate and the alum were added to the reaction mixture in total amounts which yield a sodium aluminosilicate product of the formula Na 2 O.AI 2 O 3 4 X SiO 2 YY 2 O wherein X is from about 2 to about 3.4 and Y is from about 2X to approximately 3X. The process set forth above demonstrates that the sodium aluminosilicate products in accordance with the present invention can be readily prepared, with relatively short production times and low costs required for the preparation of the products. The sodium aluminosilicate products of the invention have a high water demand so that when used in dental compositions, the dental compositions may include relatively high levels of water and relatively low levels of humectant. For example, in the preferred embodiment, the sodium aluminosilicate products of the present invention have a water demand of more than 50 g of water per 100 g of product. Preferably, the products have an upper limit of water demand of about 90 g of water per 100 g of product. The sodium aluminosilicate products preferably have a lower demand for humectant of less than about 80 g of humectant per 100 g of product. Additionally, sodium aluminosilicate products have a relatively large pore size, for example, a larger total pore volume of about 1.40 as measured by the mercury intrusion method. The sodium aluminosilicate products of the present invention are further advantageous because they are compatible with fluoride-providing materials such as monofluorophosphates. This highlights the advantages of the use of sodium aluminosilicate products in dental formulations. The following examples demonstrate that the sodium aluminosilicate products and the dental compositions of the present invention. Unless otherwise indicated, all the parts and percentages established in the examples and through the present specification are by weight.

EXAMPLE 1 This example demonstrates the production of sodium aluminosilicate products in accordance with the present invention. To a 113.55 liter reactor 30 liters of a 10-15% solution of Na2SO4 are added. This solution is continuously stirred and heated to 87.7 ° C ± whose temperature is maintained throughout the reaction. Agitation is also continued throughout the reaction. This reaction is initiated by the addition of a 20-22% sodium silicate solution (heated to approximately 48.8 ° C) for exactly one minute at a rate of one liter per minute. Sodium silicate has a molar ratio of SiO2 / Na2 = of 2.65. After one minute a 40-48% alum solution (AI2 (SO4) 3-H2O) heated to a temperature of about 48.8 ° C is also added at a rate of 0.4 liter per minute. The pH of the reaction medium is this point is approximately 10.2. as the addition of alum and silicate continues, the pH of the reaction drops to about 8.4 in about 10 minutes. At this point, the alum speed is reduced to 0.3 liter per minute to maintain the pH of the reaction at 8.5. After a total silicate addition time of 43 minutes has passed, the silicate flow stops. The addition of alum continues until the pH of the reaction has dropped to 5.9 ± 0.1. At this point, the addition of alum is stopped. The reaction is allowed to digest for 15 minutes to allow a complete reaction. The reaction paste is filtered and washed to remove the Na2SO2 by-product. The cake batter is sprayed to a moisture content of about 5% and milled to reduce the particle size to about 9 microns (average particle size). The resulting sodium aluminosilicate product was subjected to chemical and physical analysis, the results of which were as follows: Physical Properties: Oil Absorption, cc / 100g 68 Surface Area, m2 / g 43 Gloss 97.2 Average Particle Size, microns 8.94 Mass Density, lb / f 38.4 Chemical Analysis: Na2O 4-7 AI2O3 9-13 SiO2 66-76 Hydrated Water Rest The product was also determined to have a water demand of 64.9 g of water per 100 g. Using the mercury intrusion volume method, the product was determined to have a high pressure pore volume of 1.3152, a low pressure pore volume of 0.1546 and a total pore size of 1.47. the pore radius was measured at 5000 Á. These values are compared with those of the conventional abrasives used in the dental formulations known in Tables V and VI.

In the present specification, oil absorption is measured using the method erased ASTM D281. The surface area is determined by the BET nitrogen adsorption method of Brunar et al, J. Am. Chem Soc, 60, 309 (1938). To measure the brightness, fine powder materials that are pressed into a smooth smoothed pellet using a "Technidyne Brightimeter" are evaluated. This instrument has a double beam optical system where the samples are illuminated at an angle of 45 ° and the reflected light seen at 0o, adheres to the TAPPI test methods T452 and T646, and the ASTM D985 Standard. A series of filters direct the reflected light of the desired wavelengths towards a photocell where they are converted to an output voltage. This signal is then amplified and processed by an internal microcomputer for display and printing. The average particle size is measured using a Microtrac II, Leeds and Northrup apparatus. Specifically, a laser beam is projected through a transparent cell that contains a stream of moving particles suspended in a liquid. The light rays hitting the particles are scattered through angles that are inversely proportional to their sizes. The photoreceptor arrangement measures the amount of light at various angles predetermined The electrical signals proportional to the measured light flow values are then processed by a microcomputer system to form a multiple channel histogram of the particle size distribution. Mass density is measured by observing the volume in liters occupied by a given weight of the abrasive and then reported in pounds per cubic foot. The demand for water and the demand for humectant are determined as follows: The procedures use a Spex Mill (Spex Industries, Inc .; # 8000 Mixer Mill) that imparts a piston pin action with no shear force to the materials being tested. The appropriate test jars have a capacity of 125 ml. The test is conducted simply by weighing the samples inside the test jar, adding the test liquid and stirring in the Spex Mill. The sample weights were recorded up to 0.01 g of precision and vary with the sample being tested. The test pitcher should be filled approximately half full and the typical weights are 5 to 10 grams. The addition of liquid to the powder is facilitated by making a small hole in the powder, pouring the liquid into it and, covering it with dry powder from the sides. This prevents the liquid from adhering to the sides of the jar and lid while it is being stirred. An equal weight of liquid and sample are added to the jar and the sample is shaken on the Spex Mill for 30 seconds. This represents 50% of carrying capacity as a starting point. If a considerable amount of liquid adheres to the sides of the jar, it should be scraped with a spatula before adding additional liquid. The sample is observed to confirm that all the liquid has in fact been taken into the sample. More liquid is then added to the same jar and the mixture is stirred for an additional 30 seconds. This procedure is repeated until a condition is observed in which the mixture of dry powder and the wet lumps or granules has resulted. Small increments of liquid are added at this point (approximately 0.3 to 0.5 grams). The mixture will gradually change from dust and lumps to a condition where all the dust has dispersed. This represents the end point and has the appearance of "motion paste". The end point is a condition where the sample has been completely saturated and the resulting mixture becomes sticky to the touch. The weight of added liquid water or humectant is used to calculate the water or humectant demand, respectively, per 100 g of sample. The humectants commonly used in the present invention are glycerin and sorbitol. Pore volumes (pore mercury volumes) are determined using an Autoscan 60 Porosimeter (Quantachrome Corporation). This instrument measures the void volume and the pore size distribution of various materials. Mercury is forced into the voids as a function of the pressure and the volume of mercury introduced per gram of sample is calculated at each pressure setting. The total pore volume expressed herein represents the cumulative volume of mercury introduced at pressures from vacuum to 4218. kg / cm 2. the increases in volume (cc / g) at each pressure setting are plotted against the pore radius corresponding to the pressure setting increments. The peak in the volume entered against the curve of the pore radius corresponds to the mode in the pore size distribution. Identify the most common pore size in the sample.

EXAMPLE 2 This example demonstrates the dental compositions according to the present invention. The components included in each composition are set forth in Table VII together with the amount in which each component was included in the respective composition in parts by weight.

The abrasive employed in those compositions comprises sodium aluminosilicate prepared generally in accordance with the methods set forth in Example 1. In compositions 1-3, the humectant comprises sorbitol used in the form of a 70% solution. In compositions 4-6, the humectant comprises glycerin employed in a 99.5% solution. in each of the compositions 1-6, the binder comprises a carboxymethylcellulose (CMC-7MXF). As set forth in Table VI, compositions 2 and 5 include monofluorophosphate compound (MFP) to provide therapeutic value to the compositions. Additionally each of the compositions includes a combination of preservative, sweetener, flavoring agent, blasting agent and the surfactant which combine to constitute 3.05 parts by weight of the compositions. The compositions set forth in this example clean well and have a good appearance, including good permanence and gloss. The compositions also exhibit a pleasant texture and mouth feel. The compositions are advantageous in that the abrasive is relatively inexpensive in its manufacture and the compositions have a relatively high water removal and a low demand for wetting, thus providing a relatively inexpensive product. Additionnally, as demonstrated by compositions 2 and 5, those compositions have good compatibility with monofluorophosphate compounds.

EXAMPLE 3 This example further demonstrates dental compositions in accordance with the present invention as set forth in Table VI I I. Specifically, formulations 7-9 are in accordance with the invention, while formulation 10 represents a classic dental formulation as described above including dicalcium phosphate as the abrasive. In the formulations according to the present invention, the abrasive content of the compositions was varied from 25% by weight to 35% by weight. The different measured properties of the formulations used in this example are set forth in Table IX. 0 Radioactive Dentin Abrasion 00 Slim Skin Cleaning Ratio Therefore, the dental compositions of the invention have good abrasion and cleaning properties. Preferably, the current dental compositions have RDA values of at least 8.0 and more preferably of less than 90 and PCR values of at least 75 and more preferably of at least 80. Within the present specification, the availability of fluoride is determined using a soluble floruro method. In this method, the toothpaste compositions are stored for a specified time and temperature in a rolled tube. Subsequently, 10 grams of the composition are placed in a 10 ml laboratory beaker and then 45.0 grams of distilled water are added. The mixture is stirred to form a paste in which the toothpaste is uniformly dispersed. The paste is subsequently centrifuged for 10 minutes at 15,000 rpm or until the supernatant is clear. After pipetting 10 ml of the supernatant into a plastic container. Subsequently, 5 ml of the 2 molar perchloric acid are pipetted in the same manner into the plastic container. The container is covered, mixed and allowed to stand at room temperature for 24 hours. Then 25 ml of 1.5 molar sodium citrate buffer is pipetted into the vessel. The sodium citrate regulator is prepared by dissolving 220.6 grams of sodium citrate in 500 ml of distilled water. A magnetic stirring bar is added and moderate agitation is initiated. The fluoride ion concentration is determined by direct potentiometry with Orion fluorine electrode (Model 95-09) to determine parts per million (ppm of fluorine in the supernatant.) The fluorine availability value is then calculated by expressing the soluble fluorine measured in ppm., as a percentage of the theoretically available soluble fluorine. The RDA values (radioactive dentine abrasion) were determined in accordance with the method established by Hefferren, Journal of Dental Research, July-August 1976, pp. 563-573 and described in the US patents of Wason Nos. 4,430,583, 4,420,312 and 4,421,527 whose publication and patents are incorporated herein by reference. The PCR cleaning values (Thin Skin Cleaning Ratio) were determined as follows: Permanent central bovine incisors were cut to obtain labial enamel samples of approximately 10 x 10 mm. The enamel samples were then embedded in a self-polymerization methacrylate resin so that only the enamel surfaces were exposed. The enamel surfaces were then smoothed and polished on a lapidary wheel and lightly etched to accelerate the accumulation of stains and adhesion. They were placed on a revolving bar (in an incubator at 37 ° C) by exposing them alternately to the air and to a solution consisting of triple triplicate soy, thé, coffee, mucin, FeCI3 and "Sarcina lutea". The dyeing broth was changed and the samples were rinsed twice daily for four days. After four days, a thin-skinned film dyed dark on the enamel surfaces was evident. The samples were rinsed, allowed to air dry and refrigerated until use. All products were tested using samples prepared at the same time. The amount of in vitro dyeing was photometrically graded (Minolta C221 colorimeter) using only the L value of the LAB scale. The area of the samples recorded was a circle of 0.635 cm in diameter at the center of the enamel of 10 x 10 mm. Samples with records between 25-40 (with 25 being the darkest dyeing) were used. Based on these records, the samples were divided into groups of 8 samples each, with each group having the same average baseline record. The samples were then mounted on a mechanical V-8 transverse brushing machine equipped with soft nylon filament toothbrushes (Oral-B 40). The tension on the enamel surface was adjusted to 150 g. The toothpastes were used as pastes prepared by mixing 25 grams of toothpaste with 40 ml of deionized water. The ADA reference material was prepared by mixing 10 g of material and 50 ml of a 0.5% CMC solution. Samples were brushed for 800 movements (4% minutes). To minimize the mechanical variables, a sample of each group is brushed on each of the eight brushing heads. Fresh pastas were made after being used to brush four teeth. After brushing, the samples were rinsed, dried by blotted method and re-recorded for dyeing as described above. The study was repeated with a second set of eight samples in each group for a total group of N of 16. The difference between the pre-brushing and post-dyeing records was determined and the mean and standard error was calculated for the group of reference in each study.

The cleanup ratio for the two groups of reference material (one in each study) was assigned a value of 100. The average decrease for each reference group was divided by 100 to obtain a constant value for multiple times of each decrease in individual test within each study. The individual cleaning ratio of each sample was then calculated (constant decrease x) The mean and the SEM for each group (N = 16) was then calculated using the individual cleaning ratios.The higher the value of the cleaning ratio, the higher the The amount of thin film stained removed in this test The statistical analysis of the individual means was performed using the Bartlett Chi-square test for homogeneity of variance (at a = 0.10) since the variance homogeneity could be assumed, the ANOVA to determine the significant differences A significant "F" value was indicated, so that the "Student Newman Keuls (SNK) test was used to statistically determine the significant differences between the individual means." The previous examples are established to illustrate specific modalities. of the invention and is not intended to limit the scope of the compositions and methods of the present invention. Additional and advantageous ades within the scope of the claimed invention will be apparent to one skilled in the art.

Claims (25)

1 . A dental composition, comprising an abrasive, a wetting material, water and a binder, the abrasive comprising sodium aluminosilicate having a water demand of more than 50 g of water per 100 g of product and, the dental composition that It comprises a weight ratio of water to brassy greater than 1.

2. A dental composition as defined in claim 1, comprising from about 1 5 to about 35 percent by weight of the abrasive, from about 10 to about 25 percent by weight of the wetting material, from about 35 to about 70 percent by weight of water, and from about 0.1 to about 5 percent by weight of the binder.

3. A dental composition as defined in claim 2, comprising from about 20 to about 30 weight percent of the abrasive, from about 15 to about 23 weight percent of the wetting material, from about 40 to about 60 weight percent. percent by weight of water and from about 0.5 to about 2 percent by weight of the binder.

4. A dental composition as defined in claim 1, wherein the humectant material is selected from the group consisting of glycerin, sorbitol, xylitol, propylene glycol, corn syrup, glucose and mixtures thereof.

5. A dental composition as defined in claim 1, the binder is selected from the group consisting of alkali metal carboxymethylcelluloses, hydroxyethylcarboxymethylcelluloses, natural and synthetic gums, polyvinylpyrrolidone, starch, water soluble hydrophilic colloidal carboxylic polymers, colloids of seaweed and mixtures thereof.

6. A dental composition as defined in the claim 1, which further comprises at least one additive selected from the group consisting of fluoride-providing compounds, flavoring agents, coloring agents, bleaching agents, preservatives, foaming agents and antibacterial agents.

7. A dental composition as defined in the claim 6, wherein at least the additive is added in an amount of about 0.1 to about 2 weight percent.

8. A dental composition as defined in claim 1, having an RDA value of at least 80.

9. A dental composition as defined in claim 1. 1, which has a PCR value of at least 75.

10. A method for producing a sodium aluminosilicate in the form of a particle, comprising the steps of providing an aqueous solution of sodium sulfate with stirring; add the sodium silicate to an aqueous solution and once the pH of the aqueous solution reaches approximately 10.2, continue the addition of the sodium silicate and simultaneously add alum to the aqueous solution; continue the addition of sodium silicate and alum to the aqueous solution to reduce the pH of the aqueous solution to about 8.4 and then reduce the addition rate of the alum to maintain the pH at about 8.5; complete the addition of the sodium silicate and continue the addition of the alum to the aqueous solution until the pH of the solution reaches approximately 5.9; and let the reaction mixture be digested.

11. A method as defined in claim 10, wherein the aqueous solution of sodium silicate is heated to a temperature of at least 60 ° C.

12. A method as defined in claim 10, further including the steps of filtering the digested mixture and washing the sodium aluminosilicate product. A method as defined in claim 12, which includes the additional step of drying the sodium aluminosilicate product to a moisture content of about 5 percent. A method as defined in claim 13, which includes the additional step of grinding the dried product to provide an average particle size of about 9 microns. 15. A method as defined in claim 10, wherein the sodium silicate and the alum were added in total amounts that provide a sodium aluminosilicate product of the formula Na 2 O.AI 2 O 3 4 X SiO 2 .YH 2 O wherein X is from about 2 to about 3.4 and Y is about 2X up to approximately 3X. 16. A method as defined in claim 15, wherein X is from about 2.6 to about 3.3. 17. A method as defined in claim 10, wherein the sodium silicate is added in the form of an aqueous solution at a temperature of about 48.8 ° C. 18. A method as defined in claim 10, wherein the alum is added in the form of an aqueous solution at a temperature of about 48.8 ° C. 19. The sodium aluminosilicate produced in accordance with the method of claim 10. 20. Sodium aluminosilicate for use in dental compositions, sodium aluminosilicate having the formula Na2O.AI2O3.4XSiO2.YH2O wherein X is from about 2 to about 3.4 and Y is from about 2X to about 3X and, which has a water demand of more than 50g of water per 100g of sodium aluminosilicate product and less than 90 g of water per 100 g of sodium aluminosilicate product. 21. The sodium aluminosilicate as defined by claim 20, which has a demand for humectant of less than 80 g of humectant per 100 g of sodium aluminosilicate. 22. The sodium aluminosilicate as defined by claim 20, which has a total pore volume of more than about 1.40 cc / g, as measured by the mercury intrusion method. 23. The sodium aluminosilicate as defined by claim 20, which has a mass density of less than about 45 pounds per cubic foot. 24. The sodium aluminosilicate as defined by claim 20, which has an average particle size of about 9 microns. 25. The sodium aluminosilicate as defined by claim 20, comprising, in percentages by weight, 4-7% Na 2 O, 9-13% AI 2 O 3 and 66-76% SiO 2 and the remainder of water.