EA038664B1 - Oral care composition - Google Patents

Abstract

An oral care composition is disclosed comprising calcium silicate, from 1 to 20 wt.% of a potassium phosphate salt, a tubule blockage enhancer selected from calcium dihydrogen phosphate, calcium sulfate hemihydrate or mixtures thereof and a physiologically acceptable carrier, wherein the calcium silicate and the potassium phosphate salt is present in a weight ratio from 10:1 to 1:5.

Description

The technical field to which the invention relates

The present invention relates to compositions for the care of the oral cavity, such as toothpastes, powders, chewing gums, mouth rinses and the like. In particular, the present invention relates to an oral composition comprising calcium silicate, potassium phosphoric acid and a tubule blocking enhancer that results in desensitization and / or remineralization of teeth. The invention also relates to the use of such compositions for the treatment of hypersensitivity and / or remineralization of teeth, and / or whitening of the teeth of an individual.

Prior art

Dental hypersensitivity is a temporarily induced sensation of pain that affects up to 20% of the adult population. Hypersensitive teeth can be sensitive to temperature, pressure, or chemical attack.

Dentin of the tooth generally contains channels called tubules that allow osmotic flow between the interior of the pulp of the tooth and the outer surfaces of the root. Tooth hypersensitivity can be associated with a general increase in exposed root surfaces of teeth as a result of periodontal disease, toothbrush abrasion or fatigue under cyclic loading of thin enamel near the dentin-enamel junction. When the root surfaces are exposed, the dentinal tubules are also exposed.

The currently accepted theory for dental hypersensitivity is the hydrodynamic theory, based on the belief that exposed exposed dentinal tubules allow fluid to flow through the tubules. This flow excites nerve endings in the dental pulp. A clinical copy of the sensitive teeth observed in SEM (scanning electron microscopy) showed a variable number of open or partially occluded dentinal tubules.

There are various approaches to treating tooth hypersensitivity. One approach is to reduce nerve excitability in a sensitive tooth using nerve depolarizing agents containing strontium ions, potassium salts such as potassium nitrate, potassium bicarbonate, potassium chloride, and the like. These nerve depolarizing agents act by interfering with nerve transduction of the pain stimulus, making the nerve less sensitive.

Another approach is to use tubule blocking agents that completely or partially seal the tubules, such as polystyrene beads, apatite, polyacrylic acid, mineral hectorite clay, and the like. These tubule blocking agents function by physically blocking the exposed ends of the dentinal tubules, thereby reducing the movement of dentinal fluid and reducing the irritation associated with shear stress described by hydrodynamic theory.

An ideal tubule blocking agent should result in faster and more prolonged tubular occlusion. Tubular occlusion can be achieved either by the deposition of mineral crystals on the surfaces of the dentin and / or within the dentinal tubules. Superficial deposition of mineral crystals on dentin surfaces can provide short-term relief, but sediment can be removed by daily brushing and / or dissolving with saliva and / or drinking acidic drinks. Dentinal tubular occlusion provides effective treatment with long-term benefits.

There remains a need to treat dental hypersensitivity with a more effective approach. The present inventors have surprisingly found that an oral composition comprising calcium silicate, potassium phosphoric acid and a tubule blocking enhancer provides excellent tubule blocking performance for desensitizing teeth. In addition, such a composition can also increase the efficiency of tooth remineralization and / or the deposition of particulate whitening agent on tooth surfaces to provide a tooth whitening advantage.

Additional Information

WO 2008/068149 A (Unilever) discloses an oral care product containing a first composition containing an insoluble calcium salt that is not a calcium salt of phosphoric acid, a second independent composition containing a phosphate ion source, and delivery devices for each from compositions to the surface of the teeth. The preferred insoluble calcium salt is calcium silicate.

The above publication does not describe an oral composition containing calcium silicate, 1 to 20 wt% potassium salt of phosphoric acid and a tubule blocking enhancer selected from calcium dihydrogen phosphate, calcium sulfate hemihydrate or mixtures thereof, wherein calcium silicate and the potassium salt of phosphoric acid is present in a weight ratio of 10: 1 to 1: 5, and especially that such an oral care composition can treat tooth hypersensitivity and / or increase the efficiency of tooth remineralization.

Research and definitions

Means for cleaning teeth

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Dentifrice for the purposes of the present invention means a paste, powder, liquid, chewing gum or other preparation for cleaning teeth or other surfaces in the oral cavity.

Toothpaste

Toothpaste for the purposes of the present invention means a toothpaste or gel-like dentifrice for use with a toothbrush. Particularly preferred are toothpastes suitable for brushing your teeth for about two minutes.

Particle size

Particle size for the purposes of the present invention means the D50 particle size. The particle size D50 of the particulate material is the diameter of the particles in which 50 wt% of the particles have a larger diameter and 50 wt% have a smaller diameter. For the purposes of the present invention, particle size and distribution are measured using a Malvern Mastersizer 2000 and a Malvern ZetaSizer Nano series.

Composite particle

For the purposes of the present invention, a composite particle means a particle comprising a core based on a first component and a coating based on a second component, the core and the coating being composed of different materials.

Refractive index

The refractive index was determined at a temperature of 25 ° C and a wavelength of 589 nm.

Tubular Blocking Amplifier

A tubule blocking enhancer for the purposes of the present invention means a material that promotes the deposition of active substances, such as calcium silicate, and / or other beneficial agents from the continuous phase of the composition on the surfaces of dentin and / or in the dentinal tubules, inducing the in situ formation of calcium phosphate occluding the dentinal tubules and / or their exposed open ends. Preferred agents used herein mean active agents typically delivered to human teeth and / or the oral cavity, including the gums, to enhance or enhance the characteristics of these dental tissues.

PH

The pH value is adjusted at atmospheric pressure and a temperature of 25 ° C. When it comes to the pH of an oral composition, this means that the pH is measured when 5 parts by weight of the composition are uniformly dispersed and / or dissolved in 20 parts by weight of pure water at 25 ° C. In particular, pH can be measured by manually mixing 5 g of the oral care composition with 20 ml of water for 30 seconds, followed by immediate measurement of the pH with a pH indicator or pH meter.

Solubility

Soluble and insoluble for the purposes of the present invention means the solubility of the source (eg, calcium salts) in water at 25 ° C and atmospheric pressure. Soluble means a source that dissolves in water to form a solution having a concentration of at least 0.1 mol per liter. Insoluble means a source that dissolves in water to form a solution having a concentration of less than 0.001 mol per liter. Thus, the term sparingly soluble means a source that dissolves in water to form a solution having a concentration of more than 0.001 mol per liter and less than 0.1 mol per liter.

Hydration water

Hydration water for the purposes of the present invention means water chemically combined with a substance in such a way that it can be removed by heating without significantly changing the chemical composition of the substance. In particular, water, which can only be removed by heating above 200 ° C. Water loss is measured by thermogravimetric analysis (TGA) with the Netzsch TG instrument. TGA is carried out in an atmosphere of N ₂ with a heating rate of 10 degrees / min in the range from 30 to 900 ° C.

Essentially does not contain

Substantially free for the purposes of the present invention means less than 1.5 wt% and preferably less than 1.0 wt% and more preferably less than 0.75 wt% and even more preferably less than 0.5 wt% .%, and even more preferably less than 0.1 wt.%, and most preferably from 0.0 to 0.01 wt.%, based on the total weight of the composition for caring for the oral cavity, including all ranges in the specified ranges.

Biphasic

Biphasic for the purposes of the present invention means a composition having two independent phases that are physically separate.

Anhydrous composition

Anhydrous composition for the purposes of the present invention means that the water content of the composition is less than 1.5%, preferably from 0.0 to 0.75%, based on the total weight of the oral care composition.

Viscosity

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The viscosity of a toothpaste is a value measured at room temperature (25 ° C) using a Brookfield viscometer, spindle # 4, and at a speed of 5 rpm. Values are in centipoise (cP = mPa-s) unless otherwise indicated.

Remineralization

Remineralization for the purposes of the present invention means in situ (i.e. in the oral cavity) formation of calcium phosphate on teeth (including layers on teeth from 10 nm to 20 microns and preferably from 75 nm to 10 microns, and most preferably from 150 nm to 5 microns thick including all intervals within the range), to reduce the likelihood of tooth sensitivity, dental caries, to regenerate enamel and / or improve the appearance of teeth by whitening through the formation of such new calcium phosphate.

Other terms

Except for the examples, or where expressly indicated otherwise, all numbers in this description indicating amounts of material or reaction conditions, physical properties of materials and / or use, may optionally be considered as modified by the word about.

All amounts are by weight of the final oral composition unless otherwise indicated.

It should be noted that when specifying any ranges of values, any particular high value can be associated with any specific low value.

For the avoidance of doubt, the word containing means including, but not necessarily consisting of, or consists of. In other words, the steps or options listed should not be exhaustive.

The disclosure provided herein is intended to embrace all of the embodiments contained in the claims as a plurality of dependent claims, regardless of whether the claims may be found without multiple dependence or redundancy.

Where a feature is disclosed in part of a specific aspect of the invention (eg, a composition according to the present invention), such disclosure should also be considered applicable to any other aspect of the invention (eg, a method according to the invention) mutatis mutandis.

Brief description of the invention

In a first aspect, the present invention relates to an oral composition comprising:

a) calcium silicate;

b) 1 to 20% by weight of the potassium salt of phosphoric acid;

c) a tubular occlusion enhancer selected from calcium dihydrogen phosphate, calcium sulfate hemihydrate, or mixtures thereof; and

d) a physiologically acceptable carrier, wherein calcium silicate and potassium phosphoric acid are present in a weight ratio of 10: 1 to 1: 5.

In a second aspect, the present invention relates to a packaged oral care product containing an oral care composition according to the first aspect of the present invention.

In a third aspect, the present invention relates to a method for desensitizing and / or remineralizing and / or whitening an individual's teeth, comprising the step of applying an oral composition according to any embodiment of the first aspect to at least one surface of the individual's teeth.

All other aspects of the present invention will become more readily apparent upon consideration of the detailed description and examples that follow.

Detailed description of the invention

It has been found that an oral composition containing calcium silicate, potassium phosphoric acid and a tubule blocking enhancer provides excellent tubule blocking efficacy for desensitizing teeth. In addition, such a composition can also enhance the tooth remineralization efficiency and / or the deposition of particulate whitening agent on the tooth surfaces to provide a tooth whitening effect.

Calcium silicate

In a preferred embodiment, calcium silicate is used which has low water solubility and is commercially available under the name Sorbosil CA40 from PQ Corporation. In another preferred embodiment, calcium silicate is insoluble, present as a calcium oxide-silicon dioxide (CaO-SiO ₂ ) composite material, which is described, for example, in international patent application published as WO 2008/01517 (Unilever), which is included to this document by reference in its entirety. For a composite material based on calcium silicate, the atomic ratio of calcium to silicon (Ca: Si) can be 3 038664 from 1:30 to 5: 1. The Ca: Si ratio is preferably 1:20 to 3: 1, and more preferably 1:10 to 3: 1, and most preferably 1: 7 to 3: 1. Calcium silicate may contain monocalcium silicate, bicalcium silicate or tricalcium silicate. Calcium silicate can be in a crystalline or amorphous state, or even in a mesoporous state.

In addition to calcium oxide, silicon dioxide, particles containing calcium silicate that is not hydrated may contain other components such as metal cations, anions (such as phosphate), and the like. However, it is preferred that the particles contain calcium oxide, silicon dioxide in an amount of at least 70% by weight of the particles, more preferably at least 80%, even more preferably at least 90%, and even more preferably at least 95 %. Most preferably, the particles consist of (or at least essentially consist of) calcium oxide, silicon dioxide.

In another preferred embodiment, the calcium silicate is calcium silicate hydrate. The calcium silicate hydrate for use in the present invention contains at least calcium oxide (CaO), silicon dioxide (SiO ₂ ) and water. Compared to conventional calcium silicate which is not hydrated, calcium silicate hydrate contains hydration water in an amount of at least 5% by weight of calcium silicate hydrate, preferably at least 10%, more preferably at least 15%, even more preferably at least at least 20% and most preferably at least 25%. The water content is usually not more than 50% by weight of calcium silicate hydrate, more preferably not more than 40%, even more preferably not more than 35%, and most preferably not more than 30%.

The calcium silicate hydrate preferably contains at least 20% silicon dioxide by weight of calcium silicate hydrate, more preferably at least 30%, more preferably at least 40% and most preferably at least 55%. The silica content is preferably not more than 70% by weight of calcium silicate hydrate, more preferably not more than 65%, and most preferably not more than 60%.

To provide the calcium required for remineralization, the calcium silicate hydrate preferably contains calcium oxide in an amount of at least 5% by weight of calcium silicate hydrate, more preferably at least 7%, even more preferably at least 10%, even more preferably at least at least 12%, and most preferably at least 15%. The calcium oxide content is generally not more than 50% by weight of calcium silicate hydrate, more preferably not more than 40%, even more preferably not more than 30%, and most preferably not more than 25%.

The calcium silicate hydrate preferably contains Ca and Si in an atomic ratio (Ca: Si) of less than 3: 1, more preferably less than 1: 1, even more preferably from 1: 1.5 to 1: 4 and most preferably from 1: 1 , 7 to 1: 3.

Calcium silicate can be amorphous or at least partially crystalline or mesoporous. The calcium silicate is preferably in particulate form as this provides the maximum surface area for contact with dental tissue. Thus, preferably the composition contains particles containing calcium silicate. Preferably from 10 to 100% and especially from 25 to 100% and most preferably from 70 to 100% by weight of the particles containing calcium silicate used in this invention have a particle size of from 100 nm to less than 50 microns, preferably from 500 nm up to 30 microns, more preferably from 1 to 20 microns, most preferably from 1 to 10 microns.

In addition to calcium oxide, silicon dioxide and water, particles that contain calcium silicate hydrate may contain other components such as metal cations, anions (such as phosphate), and the like. However, it is preferred that the particles contain CaO, SiO ₂ and water in an amount of at least 70% by weight of the particles, more preferably at least 80%, even more preferably at least 90% and even more preferably at least 95 %. Most preferably, the particles consist of (or at least essentially consist of) CaO, SiO ₂ and water.

Typically, the oral composition of the present invention contains 1 to 8% by weight of calcium silicate, more preferably 3 to 50%, most preferably 5 to 30%, based on the total weight of the oral composition, and including all ranges within these limits.

Potassium salt of phosphoric acid

The potassium salt of phosphoric acid suitable for use in this invention is capable of reacting with calcium silicate used to form hydroxyapatite in situ.

The potassium salt of phosphoric acid that can be used in the present invention includes potassium dihydrogen phosphate, dipotassium hydrogen phosphate, or mixtures thereof.

In one preferred embodiment, the potassium salt of phosphoric acid contains or is potassium dihydrogen phosphate.

In another preferred embodiment, the potassium salt of phosphoric acid contains or is a mixture of potassium dihydrogen phosphate and dipotassium hydrogen phosphate. Mix is preferred

- 4038664 contains potassium dihydrogen phosphate and dipotassium hydrogen phosphate in a weight ratio of 20: 1 to 1:10, more preferably 10: 1 to 1: 1.

Preferably, the potassium salt of phosphoric acid results in an oral composition having a pH of 4.0 to 10.0, more preferably 5.0 to 8.0, and most preferably 5.5 to 7.5.

The oral composition of the present invention contains 1 to 20% by weight of the potassium salt of phosphoric acid, preferably 3 to 18%, most preferably 5 to 10%, based on the total weight of the oral composition and includes all ranges within these limits.

The oral composition contains calcium silicate and potassium phosphoric acid in a weight ratio of 10: 1 to 1: 5, preferably 5: 1 to 1: 3, most preferably 3: 1 to 1: 1.

Tubular Blocking Amplifier

A tubule blocking enhancer suitable for use in the present invention is limited only to the extent that it can be used in the oral cavity. In a preferred embodiment, the tubule blocking enhancer provides a large amount of calcium ions in the mouth and is inexpensive and common. In a particularly preferred embodiment, the tubule blocking enhancer is a calcium salt.

It has been found that the materials used as tubule blocking enhancers in this invention are biocompatible and react quickly with water and are completely resorbed on the tooth surface, so they can be used to promote the deposition of oral care actives on the tooth surface. such as calcium silicate, and / or other beneficial agents.

The tubule blocking enhancer is selected from calcium dihydrogen phosphate, calcium sulfate hemihydrate, or mixtures thereof.

Typically, the oral composition for caring for the oral cavity according to the present invention contains from 0.1 to 20 wt.% Tubular blocking enhancer, more preferably from 0.2 to 15 wt.%, Even more preferably from 0.5 to 10 wt. %, most preferably from 1 to 5 wt.%, based on the total weight of the composition for the care of the oral cavity and including all ranges within the specified ranges.

The oral composition preferably contains calcium silicate and a tubule blocking enhancer in a weight ratio of 20: 1 to 1: 5, more preferably 15: 1 to 1: 3, most preferably 10: 1 to 1: 1.

Carrier

The composition of the present invention is an oral care composition and usually contains a physiologically acceptable carrier. The carrier preferably includes at least a surfactant, thickener, humectant, or a combination thereof.

Preferably, the oral composition contains a surfactant. Preferably, the composition contains at least 0.01% surfactant by weight of the composition, more preferably at least 0.1%, and most preferably 0.5 to 7%. Suitable surfactants include anionic surfactants such as sodium, magnesium, ammonium or ethanolamine salts of C8-C18 alkyl sulfates (e.g. sodium lauryl sulfate), C8-C18 alkyl sulfosuccinates (e.g. sodium dioctyl sulfosuccinate), C8-C18 alkyl sulfates as sodium lauryl sulfate), C8-C18 alkyl sarcosinates (such as sodium lauryl sarcosinate), C8-C18 alkyl phosphates (which may optionally contain up to 10 ethylene oxide and / or propylene oxide units) and sulfated monoglycerides. Other suitable surfactants include nonionic surfactants such as optionally sorbitan polyethoxylated fatty acid esters, ethoxylated fatty acids, polyethylene glycol esters, monoglyceride and diglyceride fatty acid ethoxylates, and ethylene oxide / propylene oxide block polymers. Other suitable surfactants include amphoteric surfactants such as betaines or sulfobetaines. Also, mixtures of any of the above materials can be used. More preferably, the surfactant includes or is an anionic surfactant. Preferred anionic surfactants are sodium lauryl sulfate and / or sodium dodecylbenzenesulfonate. The most preferred surfactant is sodium lauryl sulfate, sodium coco sulfate, cocamidopropyl betaine, or mixtures thereof.

A thickener can also be used in this invention, and is limited only to the extent that the same can be added to the composition suitable for use in the mouth. Illustrative examples of the types of thickeners that can be used in the present invention include sodium carboxymethyl cellulose (SCMC), hydroxyethyl cellulose, methyl cellulose, ethyl cellulose 5,038664, gum tragacanth, gum arabic, gum karaya, sodium alginate, carrageenan and guar moss, starch, modified starch, silica thickeners, including silica aerogels, magnesium aluminum silicate (e.g.

Veegum), carbomers (crosslinked acrylates) and mixtures thereof.

Generally, xanthan gum and / or sodium carboxymethyl cellulose and / or carbomer are / are preferred. When carbomer is used, those that have a weight average molecular weight of at least 700,000 are desirable, and preferably those that have a molecular weight of at least 12,000,000, and most preferably those that have a molecular weight of at least about 250,000. Mixtures of carbomers also can be used in this document.

In a particularly preferred embodiment, the carbomer is Synthalen PNC, Synthalen KP, or a mixture thereof. It has been described as a high molecular weight and crosslinked polyacrylic acid and identified under CAS number 9063-87-0. These types of materials are commercially available from suppliers such as Sigma.

In another particularly preferred embodiment, the sodium carboxymethyl cellulose (SCMC) used is SCMC 9H. The compound has been described as a sodium salt of a cellulose derivative with carboxymethyl groups linked to hydroxyl groups of glucopyranose backbone monomers and identified under CAS number 9004-324. This substance is available from suppliers such as Alfa Chem.

In another particularly preferred embodiment, the thickening agent is xanthan gum.

The thickener is usually 0.01 to about 10%, more preferably 0.1 to 9%, and most preferably 0.1 to 5%, by weight of the oral composition, based on the total weight of the composition and including all ranges within the specified limits. When the oral care composition of the present invention is a toothpaste or gel, it typically has a viscosity of about 30,000 to 180,000 centipoises, and preferably 60,000 to 170,000 centipoises, and most preferably 65,000 to 165,000 centipoises.

Suitable moisturizing agents are preferably used in the oral composition of the present invention and include, for example, glycerin, sorbitol, propylene glycol, dipropylene glycol, diglycerol, triacetin, mineral oil, polyethylene glycol (preferably PEG-400), alkanediols such as butanediol and hexanediol, ethanol, pentylene glycol, or mixtures thereof. Glycerin, polyethylene glycol, sorbitol, or mixtures thereof are preferred wetting agents. The moisturizing agent can be present in the range of 10 to 90% by weight of the oral care composition. More preferably, the content of the humectant in the carrier is 25 to 80%, and most preferably 30 to 60%, by weight of the composition based on the total weight of the composition and including all ranges within the indicated ranges.

Optional components

The composition for caring for the oral cavity may further contain beneficial agents that are usually delivered to the teeth of a person and / or to the oral cavity, including the gums, to enhance or improve the characteristics of these dental tissues. The only limitation on the beneficial agents that can be used in this invention is that they must be suitable for use in the oral cavity. Typically useful agents include coloring agents, biomineralizing agents, antibacterial agents, or mixtures thereof. For example, a coloring agent such as particulate whitening agents and pigments, preferably a particulate whitening agent. Preferably, the pigment, if used, is violet or blue having a hue angle, h, in the CIELAB system in the range of 220 to 320 °. These pigments can be selected from one or more of those pigments listed in the Color Index International, listed from Pigment Blue 1 to Pigment Blue 83 and Pigment Violet 1 to Pigment Violet 56; biomineralizing agents for remineralizing tooth enamel can be one or more of amorphous calcium phosphate, α-tricalcium phosphate, Ptricalcium phosphate; calcium carbonate, hydroxyapatite with calcium deficiency (Ca ₉ (HPO ₄ ) (PO ₄ ) ₅ OH), dicalcium phosphate (CaHPO ₄ ), dicalcium phosphate dehydrate (CaHPO ₄ -2H ₂ O), hydroxyapatite (Ca ₁₀ (PO ₄ ) ₆ (OH ) ₂ ), monocalcium phosphate monohydrate (Ca (H ₂ PO ₄ ) ₂ -H ₂ O), octacalcium phosphate (Ca ₈ H ₂ (PO ₄ ) ₆ -5H ₂ O) and tetralcium phosphate (Ca4 (PO ₄ ) ₂ O) ; antibacterial agents can be selected from one or more metal salts, the metal being selected from zinc, copper, silver or mixtures thereof, triclosan, triclosan monophosphate, triclocarban, curcumin, quaternary ammonium compounds, bisbiguanides and long chain tertiary amines, preferably zinc salts, including zinc oxide, zinc chloride, zinc acetate, zinc ascorbate, zinc sulfate, zinc nitrate, zinc citrate, zinc lactate, zinc peroxide, zinc fluoride, zinc ammonium sulfate, zinc bromide, zinc iodide, zinc gluconate, zinc tartrate, zinc succinate, zinc formate, zinc phenolsulfonate, zinc salicylate, zinc glycerophosphate, or a mixture thereof.

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The beneficial agent is preferably particulate as this provides the maximum surface area for contact with dental tissue.

In a preferred embodiment, the benefit agent is a particulate tooth whitening agent.

Typically, the particulate whitening agent contains a material suitable for physically and immediately improving the characteristics of teeth, and especially teeth whitening. To provide an excellent whitening effect, the material should preferably have a high refractive index of at least 1.9, more preferably at least 2.0, even more preferably at least 2.2, even more preferably at least 2.4 and most preferably at least 2.5. The maximum refractive index of the material is not particularly limited, but is preferably up to 4.0. Preferably, the material has a refractive index in the range of 1.9 to 4.0.

Particularly suitable materials are metal compounds, and compounds in which the metal is selected from zinc (Zn), titanium (Ti), zirconium (Zr), or a combination thereof are preferred. Preferably, the metal compound is (or at least contains) a metal oxide such as titanium dioxide (TiO ₂ ), zinc oxide (ZnO), zirconia (ZrO ₂ ), or a combination thereof. In addition, the particulate whitening agent may also contain non-metal oxides such as silicon monoxide (SiO).

In a preferred embodiment, the particulate bleaching agent contains metal oxides, non-metal oxides, or a combination thereof in an amount of at least 50% by weight of the bleaching agent, and more preferably at least 70%, even more preferably 80 to 100%, and most preferably 85 to 85 95%. In a particularly preferred embodiment, the particulate whitening agent is titanium dioxide in an amount of at least 50% by weight, and most preferably titanium dioxide in an amount of 60 to 100% by weight, based on the total weight of the whitening agent and including all ranges indicated. In another particularly preferred embodiment, the particulate whitening agents are poorly soluble or insoluble in water, but most preferably, insoluble in water.

In a preferred embodiment, the particulate whitening agents are composite particles. The refractive index of a composite particle containing more than one material can be calculated from the refractive indices and volume fractions of the components using effective medium theory, as described, for example, in WO 2009/023353.

The composite particle contains a core based on the first component and a coating based on the second component. Typically, the core of the composite particle contains a material suitable for physically and immediately improving the characteristics of teeth and especially teeth whitening. In order to provide an excellent whitening effect, the material should preferably have a high refractive index, which is at least 1.9, more preferably at least 2.0, even more preferably at least 2.2, even more preferably at least 2.4 and most preferably at least 2.5. The maximum value of the refractive index of the material is not particularly limited, but is preferably up to 4.0. Preferably, the material has a refractive index in the range of 1.9 to 4.0.

Particularly suitable materials are metal compounds, and compounds in which the metal is selected from zinc (Zn), titanium (Ti), zirconium (Zr), or a combination thereof are preferred. Preferably, the metal compound is (or at least contains) a metal oxide such as titanium dioxide (TiO ₂ ), zinc oxide (ZnO), zirconia (ZrO ₂ ), or a combination thereof. In addition, the core of the composite particle may also contain non-metal oxides such as silicon monoxide (SiO).

The core of the composite particle is usually 3 to 98%, and preferably 6 to 65%, and most preferably 10 to 55% by weight of the composite particle, based on the total weight of the composite particle, and including all ranges therein. In a preferred embodiment, the core contains metal oxides, non-metal oxides, or a combination thereof in an amount of at least 50% by weight of the core, and more preferably at least 70%, even more preferably 80 to 100%, and most preferably 85 to 95% ... In a particularly preferred embodiment, the core comprises at least 50% by weight of titanium dioxide, and most preferably from 60 to 100% by weight of titanium dioxide, based on the total weight of the core based on the first component.

The second component coating contains a material suitable for adhesion to tooth enamel, dentin, or both. Typically, the coating material contains the element calcium and optionally other metals such as potassium, sodium, aluminum, magnesium, and mixtures thereof, such optional metals being, for example, in the form of sulfates, lactates, oxides, carbonates or silicates. Optionally, the coating material can be alumina or silica. In a preferred embodiment, the coating material is suitable for providing a biological or chemical improvement to teeth that is long lasting (eg, leads to the formation of hydroxyapatite). Preferably, the coating used contains at least

7,038664 at least 50 wt.% Elemental calcium, and most preferably at least 65 wt.% Elemental calcium, based on the total weight of the metal in the coating. In a particularly preferred embodiment, the metal in the coating comprises 80 to 100 wt.% Elemental calcium, based on the total weight of the metal in the coating based on the second component, and includes all ranges within the indicated ranges. In another particularly preferred embodiment, the core and coating are poorly soluble or insoluble in water, but most preferably insoluble in water.

In a particularly desirable embodiment, the coating based on the second component may contain, for example, calcium phosphate, calcium gluconate, calcium oxide, calcium lactate, calcium carbonate, calcium hydroxide, calcium sulfate, calcium carboxymethyl cellulose, calcium alginate, calcium citric acid, calcium silicate, a mixture thereof or the like. In another desired embodiment, the calcium source in the coating comprises calcium silicate.

In yet another preferred embodiment, the coating may contain the element calcium, which is derived from insoluble calcium silicate, present as a calcium oxide-silicon dioxide (CaO-SiO2) composite material as described in international patent applications published as WO 2008/015117 and WO 2008/068248.

When a calcium silicate composite is used as a coating, the ratio of calcium to silicon (Ca: Si) can be from 1:10 to 3: 1. The Ca: Si ratio is preferably 1: 5 to 3: 1, and more preferably 1: 3 to 3: 1, and most preferably 1: 2 to 3: 1. Calcium silicate may contain calcium monosilicate, calcium bisilicate or calcium trisilicate, with the ratio of calcium to silicon (Ca: Si) to be understood as atomic ratios.

Typically, at least 30% of the outer surface area of the core based on the first component is coated with a coating based on the second component, preferably at least 50% of the core is coated with a coating, most preferably 70 to 100% of the outer surface area of the core based on the first component is coated coating based on the second component.

In a particularly preferred embodiment, the particulate whitening agent is titanium dioxide coated with calcium silicate.

Dispersed whitening agent in accordance with the present invention can be of various sizes and shapes. The particles can be spherical, lamellar, or irregular. The diameter of the particulate whitening agent is often from 10 nm to less than 50 microns, and preferably from 75 nm to less than 10 microns. In a particularly preferred embodiment, the particle diameter is from 100 nm to 5 microns, including all ranges within these ranges. For composite particles, in a preferred embodiment, at least 40%, and preferably at least 60%, and most preferably 75 to 99.5% of the diameter of the composite particle is the core, including all ranges within the indicated ranges.

The composition for caring for the oral cavity according to the present invention may contain one beneficial agent or a mixture of two or more beneficial agents. Typically, the beneficial agent is present in an amount from 0.25 to 60%, and more preferably from 0.5 to 40%, and most preferably from 1 to 30%, based on the total weight of the oral care composition and including all ranges within the specified ranges ...

When beneficial agents are included in the oral composition, the weight ratio of calcium silicate to beneficial agent can range from 1:10 to 5: 1, preferably from 1: 5 to 3: 1, most preferably from 1: 3 to 1: 1.

The oral composition of the present invention has been found to be effective in blocking dentinal tubules to desensitize teeth and inducing the formation of a new hydroxyapatite layer on enamel surfaces. Without wishing to be bound by theory, the present inventors believe that this may be due to the fact that the calcium silicate in the oral care composition of the present invention reacts with the potassium salt of phosphoric acid to form calcium phosphate and / or the SiOH group of silicate calcium may have an affinity for Ca ions in teeth. The tubule blocking enhancer of the present invention can further enhance the deposition of calcium silicate and / or calcium phosphate deposits on dentin and / or enamel surfaces, which further enhances the tubule blocking efficiency and / or the tooth remineralization efficiency. When beneficial agents are present in the oral care composition, remineralizing calcium silicate around the beneficial agents further helps retain these beneficial agents on dental surfaces by increasing their shear resistance.

The present inventors have surprisingly found that potassium phosphoric acid and sodium phosphoric acid have different effects on the rate of calcium phosphate nucleation. It has been found that potassium ions can inhibit the rapid formation of calcium phosphate on dentin surfaces, which allows calcium and phosphate ions to penetrate deeply into the dentinal tubules, form a nucleus and deposit within the tubules.

The composition for caring for the oral cavity according to the present invention may contain a source of phosphate in addition to the potassium salt of phosphoric acid, which is included in the composition. Such a phosphate source includes, for example, trisodium phosphate, monosodium dihydrogen phosphate, disodium hydrogen phosphate, sodium pyrophosphate, tetrasodium pyrophosphate, sodium hexametaphosphate, mixtures thereof or the like.

The oral composition of the present invention may contain a variety of other ingredients that are commonly used in the art to enhance physical properties and performance. These ingredients include antimicrobial agents, anti-inflammatory agents, anti-caries agents, plaque buffers, fluoride sources, vitamins, plant extracts, desensitizing agents, anticalculus agents, biomolecules, flavors, proteins, preservatives, opacifiers, pH adjusting agents, coloring agents sweeteners, particulate abrasives, polymeric compounds, buffers and salts for creating the pH and ionic strength of the compositions, and mixtures thereof. Such ingredients usually and together constitute less than 20% by weight of the composition, and preferably from 0.0 to 15%, and most preferably from 0.01 to 12% by weight of the composition, including all ranges within the indicated ranges.

The oral composition of the present invention can be used in a method for desensitizing and / or remineralizing and / or whitening an individual's teeth, comprising applying the composition to at least one surface of the individual's teeth. The oral composition of the present invention may additionally or alternatively be used as a medicine and / or used for the manufacture of a medicament to provide an oral care effect as described herein, for example, to reduce tooth sensitivity in an individual. Alternatively, and preferably, the use is non-therapeutic.

In a preferred embodiment, the oral composition is a single phase anhydrous composition. The composition is substantially free of water to prevent premature reaction between calcium silicate and potassium phosphoric acid salts.

In another preferred embodiment, the oral composition is a biphasic composition comprising a calcium phase and a phosphate phase, wherein the calcium silicate and tubule blocking enhancer are present in the calcium phase and potassium phosphate is present in the phosphate phase. The two phases are physically separate from each other, being in independent phases. The delivery of two independent phases to the teeth can be simultaneous or sequential. In a preferred embodiment, the phases are delivered simultaneously.

Typically, the delivery of the biphasic composition is carried out using a double tube having a first compartment for the calcium phase and a second compartment for the phosphate phase, which allows the two phases to be extruded together.

In a preferred embodiment, such a double tube has one of the compartments that surrounds the other. In such embodiments, one phase is present as a shell surrounding the other phase in the core. In a particularly preferred embodiment, the core is the calcium phase and the shell is the phosphate phase.

In another preferred embodiment, such a double tube has two compartments side by side in the same tube. In such embodiments, the implementation of the two phases is extruded from the tube as one phase, and such extrusion is called contact extrusion. In such a double tube, a pump head can be used to squeeze two phases out of the tube as one phase.

The biphasic oral composition may be a gel composition that contains two independent gel phases, the first being the calcium phase and the second being the phosphate phase. The delivery devices may include a cotton swab or spoon to which the calcium phase and phosphate phase are applied before the spoon is brought into contact with the teeth.

Typically, the composition can be packaged. In the form of a toothpaste or gel, the composition can be packaged in a conventional laminated plastic metal tube or dispenser with one compartment. The specified composition can be applied to the surfaces of the teeth using any physical means, such as a toothbrush, fingertip or applicator, directly to the sensitive area.

The composition can be effective even with daily oral hygiene use. For example, the composition can be applied to the teeth with a brush. The composition may, for example, be in contact with the teeth for a period of time ranging from 1 second to 20 hours. More preferably from 1 second to 10 hours, even more preferably from 10 seconds to 1 hour, and most preferably from 30 seconds to 5 min. The composition can be applied daily, for example, for use by an individual one, two, or three times a day. When the oral composition is a two-phase composition, the two phases of the composition are mixed during application. The mixed phases are usually left on the teeth for a period of time ranging from 3 minutes to 10 hours, more preferably from 3 minutes to 8 hours. Application can be carried out from one to five times a month.

The following examples are provided to facilitate understanding of the present invention. The examples are not intended to limit the scope of the claims.

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Examples of

Example 1

This example demonstrates improved dentinal tubule blockage by using calcium silicate, potassium phosphoric acid, and calcium dihydrogen phosphate as a tubule blockage enhancer. All ingredients are expressed as weight percent based on the total weight of the composition and as active ingredient level.

Table 1

Ingredient Samples 1 2 3 4 Glycerol 66.84 64.84 66.84 64.84 Sodium monofluorophosphate 1, and 1, and 1, and 1, and Sodium saccharin 0.25 0.25 0.25 0.25 Calcium silicate ³ 15.00 15.00 15.00 15.00 Calcium dihydrogen phosphate - 2.00 - 2.00 Sodium lauryl sulfate 2.00 2.00 2.00 2.00 Monosodium dihydrogen phosphate 3.20 3.20 - - Trisodium phosphate 3.80 3.80 - - Potassium dihydrogen phosphate - - 6.00 6.00 Dipotassium hydrogen phosphate - - 1.00 1.00 Silicon dioxide abrasive ^b 6.00 6.00 6.00 6.00 Silicon dioxide abrasive ^with 0.50 0.50 0.50 0.50 Xanthan gum 0.10 0.10 0.10 0.10 Flavoring additive 1.20 1.20 1.20 1.20

a) Commercially available calcium silicate (CaSiO ₃ ) under the tradename Sorbosil CA40 from PQ Corporation.

b) Commercially available silica under the trade name Sorbosil AC77 from PQ Corporation.

c) Commercially available silica under the tradename Sorbosil AC43 from PQ Corporation.

The ways

To assess the effectiveness of blocking the dentinal tubules, the test sample was mixed with water in a ratio of 4 g per 8 ml of water to prepare a suspension.

Human dentin discs were eroded with 37% phosphoric acid for 1 min, then treated with various suspensions by brushing following the same protocol. Dentin discs were slurried cleaned with a dental machine equipped with toothbrushes. The tooth brushing load was 170 g +/- 5 g and the automatic brushing speed was 150 rpm. After brushing for 1 min, the dentin discs were soaked in the toothpaste suspension for 1 min. The dentin discs were then rinsed with distilled water and placed in a simulated oral fluid (SOF) medium under shaking conditions in a water bath at 37 ° C and 60.0 rpm. After soaking for about 3-4 hours, the dentin discs were slurried clean with a machine using the same procedure as in the first step. Brushing was repeated three times in one day, then the dentin discs were incubated in SOF overnight (> 12 h) in a shaking water bath at 37 ° C to simulate the oral environment. The dentine specimens were brushed 7 and 14 times.

A simulated oral fluid was prepared by combining the ingredients listed in Table 2.

table 2

Ingredient Quantity / g NaCl 16.07 NaHCO ₃ 0.7 CS1 0.448 K ₂ NRO ₄ * ZN ₂ O 3.27 MgCl ₂ * 6H ₂ O 0.0622 IM HCl 40 ml CaCl ₂ 0.1998 Na ₂ SO ₄ 0.1434 Buffer Adjusting the pH to 7.0 Water Balance up to 2 l

results

After 7 cleanings, SEM (Scanning Electron Microscopy) images of the dentin discs were obtained. From the top view of the SEM images, it can be seen that Sample 3 containing potassium phosphoric acid showed better tubular blocking efficacy compared to Sample 1 containing sodium phosphoric acid. Samples 2 and 4, which additionally contained a tubule-blocking enhancer, showed even better tubule-blocking efficacy than Ob

- 10 038664 sample 3.

After 14 cleanings, in the top view of the SEM images, it can be seen that all specimens showed good deposition on the dentin surfaces and the dentinal tubules were severely blocked. But corresponding cross-sectional SEM images after 14 cleanings showed that for Samples 3 and 4, containing potassium phosphoric acid salts, the materials penetrated deeper into the dentinal tubules than Samples 1 and 2. Dentin discs treated with Samples 1 and 2 showed almost empty dentinal tubules with some occlusion near the dentin surfaces, while dentin discs treated with Sample 3 showed partial occlusion within the dentinal tubules. Sample 4 showed very deep penetration and the dentinal tubules were completely closed. EDX (Energy Dispersive X-ray Spectroscopy) analysis revealed an intra-dentinal tubule occlusion containing elements Ca, P, O and Si, indicating that calcium silicate precipitated in the dentinal tubules and induced remineralization. The SAED (Selected Area Electron Diffraction) pattern obtained with TEM (Transmission Electron Microscope) clearly shows that the occlusion within the dentinal tubules is hydroxyapatite (HAP), indicating the conversion of precipitated calcium silicate to HAP.

Example 2

This example demonstrates the effect of potassium salts in formulations on the effectiveness of dentinal tubule blocking. All ingredients are expressed as weight percent based on the total composition and as active ingredient level.

Table 3

Ingredient Samples 5 6 Glycerol 60.84 62.30 Sodium monofluorophosphate 1.11 1.11 Sodium saccharin 0.25 0.25 Calcium silicate ³ 15.00 15.00 Calcium dihydrogen phosphate 2.00 2.00 Sodium lauryl sulfate 2.00 2.00 Monosodium dihydrogen phosphate 6.00 6.00 Potassium nitrate (KNO3) 5.00 - Potassium carbonate (K ₂ COz) - 3.54 Silicon dioxide abrasive ^b 6.00 6.00 Silicon dioxide abrasive ⁰ 0.50 0.50 Xanthan gum 0.10 0.10 Flavoring additive 1.20 1.20

The ways

To assess the effectiveness of blocking dentinal tubules, the same protocol was used as described in Example 1. Dentin samples were brushed 14 times.

results

After 14 cleanings, SEM images of the dentin discs were obtained. From the top view of the SEM images, it can be seen that Samples 5 and 6 showed some deposition on the dentin surfaces, but many of the dentinal tubules were still open. Corresponding cross-sectional SEM images showed that dentin discs treated with Samples 5 and 6 were partially occluded in the dentin tubules.

Example 3

This example demonstrates that the weight ratio of potassium dihydrogen phosphate to dipotassium hydrogen phosphate can influence the effectiveness of tubular blocking. All ingredients are expressed as weight percent based on the total composition and as active ingredient level.

Table 4

Ingredient Samples 4 7 eight nine ten eleven Glycerol 64.84 64.84 64.84 64.84 64.84 64.84 Sodium monofluorophosphate 1.11 1.11 1.11 1.11 1.11 1.11 Sodium saccharin 0.25 0.25 0.25 0.25 0.25 0.25 Calcium silicate ³ 15.00 15.00 15.00 15.00 15.00 15.00 Calcium dihydrogen phosphate 2.00 2.00 2.00 2.00 2.00 2.00 Sodium lauryl sulfate 2.00 2.00 2.00 2.00 2.00 2.00 Potassium dihydrogen phosphate 6.00 7.00 4,00 2.00 - - Dipotassium hydrogen phosphate 1.00 - 3.00 5.00 7.00 - Tripotassium phosphate - - - - - 7.00 Silicon dioxide abrasive ^b 6.00 6.00 6.00 6.00 6.00 6.00 Silicon dioxide abrasive ^with 0.50 0.50 0.50 0.50 0.50 0.50 Xanthan gum 0.10 0.10 0.10 0.10 0.10 0.10 Flavoring additive 1.20 1.20 1.20 1.20 1.20 1.20

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The ways

To assess the effectiveness of blocking dentinal tubules, the same protocol was used as described in Example 1. Dentin samples were brushed 14 times.

results

After 14 cleanings, SEM images of the dentin discs were obtained. From the top view of the SEM images, it can be seen that all specimens except for Sample 11 showed good deposition on the dentin surfaces and the dentinal tubules were severely blocked. But for Sample 11 containing tripotassium phosphate, many dentinal tubules were still open. Corresponding cross-sectional SEM images showed that all samples except Sample 11 showed deep penetration into the dentinal tubules. In particular, Samples 4 and 7 showed better tubular blocking performance than other samples, with the dentinal tubules being almost completely closed.

Example 4

This example demonstrates improved deposition on the tooth surface using calcium silicate, potassium phosphoric acid and a tubule blocking enhancer. All ingredients are expressed as weight percent based on the total composition and as active ingredient level.

Table 5

Ingredient Samples 12 13 Glycerol 64.94 64.94 Sodium monofluorophosphate 1, and 1, and Sodium saccharin 0.25 0.25 Calcium silicate 15.00 15.00 Calcium dihydrogen phosphate 2.00 2.00 Sodium lauryl sulfate 2.00 2.00 Monosodium dihydrogen phosphate 3.20 - - Trisodium phosphate 3.80 - - Potassium dihydrogen phosphate - - 6.00 Dipotassium hydrogen phosphate - 1.00 Silicon dioxide abrasive ^b 6.00 6.00 Silicon dioxide abrasive ⁰ 0.50 0.50 Xanthan gum 0.10 0.10 Flavoring additive 1.10 1.10

The ways

To assess the deposition on the surfaces of the teeth, the test sample was mixed with water in a ratio of 4 g per 8 ml of water to form a suspension of toothpaste.

Bovine enamel blocks were treated with various slurries by brushing following the same protocol. The enamel blocks were cleaned from the slurry using a dentifrice equipped with toothbrushes. The tooth brushing load was 170 g +/- 5 g, and the automatic brushing was carried out at 150 rpm. After cleaning for 1 min, blocks of enamel were soaked in the toothpaste suspension for 1 min. Then the enamel blocks were washed with distilled water and placed in SOF under shaking conditions in a water bath at 37 ° C and 150.0 rpm. After soaking for about 3-4 hours, the enamel blocks were slurry cleaned with a machine using the same procedure as in the first step. Brushing was repeated three times in one day, then the enamel blocks were soaked in SOF overnight (> 12 h) under shaking conditions in a water bath at 37 ° C to simulate the oral environment. The enamel blocks were brushed 28 times.

results

After 28 cleanings, SEM images of the surfaces of the enamel blocks were obtained. The top view of the SEM images shows that Sample 13, containing potassium phosphoric acid salts, showed much better and tighter deposition on enamel surfaces than Sample 12. Corresponding cross-sectional SEM images further showed that the enamel surfaces treated with Sample 13 had much thicker new layer compared to surfaces treated with Sample 12. EDX analysis revealed Ca and P elements in the new layer, indicating that calcium silicate deposited on the enamel surfaces and induced remineralization.

Example 5

This example demonstrates the effect of calcium salts in formulations on the effectiveness of dentinal tubule blocking. All ingredients are expressed as weight percent based on the total composition and as active ingredient level.

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Table 6

Ingredient Samples 4 fourteen 15 16 Glycerol 64.84 64.84 64.84 64.84 Sodium monofluorophosphate 1, and 1, and 1, and 1, and Sodium saccharin 0.25 0.25 0.25 0.25 Calcium silicate ³ 15.00 15.00 15.00 15.00 Calcium dihydrogen phosphate 2.00 - - - - - - G hydroxyapatite - 2.00 - - Monohydrogen phosphate phosphate - - 2.00 - Calcium Sulphate Hemihydrate - - - - 2.00 Sodium lauryl sulfate 2.00 2.00 2.00 2.00 Potassium dihydrogen phosphate 6.00 6.00 6.00 6.00 Dipotassium hydrogen phosphate 1.00 1.00 1.00 1.00 Silicon dioxide abrasive ^b 6.00 6.00 6.00 6.00 Silicon dioxide abrasive ^with 0.50 0.50 0.50 0.50 Xanthan gum 0.10 0.10 0.10 0.10 Flavoring additive 1.20 1.20 1.20 1.20

The ways

To evaluate the effectiveness of blocking dentinal tubules, the same protocol was used as described in Example 1. Dentin samples were cleaned 7 and 14 times.

results

After 7 cleanings, SEM images of the dentin discs were obtained. In the top view of the SEM images, it can be seen that Sample 4 containing calcium dihydrogen phosphate showed better tubular blocking efficacy compared to the other samples. Sample 16 containing calcium sulfate hemihydrate showed better tubular blocking efficacy than Samples 14 and 15 containing hydroxyapatite and calcium monohydrogen phosphate, respectively. Samples 14 and 15 showed some deposition on dentin surfaces, but many of the dentinal tubules were still open.

Corresponding cross-sectional SEM images after 14 cleanings showed that for Sample 4 containing calcium dihydrogen phosphate, materials penetrated deeper into the dentinal tubules than other samples. Dentin discs treated with Samples 14, 15 or 16 showed almost empty dentinal tubules with some occlusion near the dentinal surfaces, while dentin discs treated with Sample 4 showed very deep penetration and the dentinal tubules were completely closed.

Claims (15)

CLAIM 1. Composition for the care of the oral cavity, containing: a) calcium silicate; b) 1 to 20% by weight of the potassium salt of phosphoric acid; c) a tubular blocking enhancer calcium dihydrogen phosphate; and d) a physiologically acceptable carrier, wherein calcium silicate and potassium phosphoric acid are present in a weight ratio of 10: 1 to 1: 5. 2. Composition for caring for the oral cavity according to claim 1, characterized in that the potassium salt of phosphoric acid is potassium dihydrogen phosphate, dipotassium hydrogen phosphate, or mixtures thereof. 3. An oral composition according to claim 2, wherein the potassium salt of phosphoric acid is potassium dihydrogen phosphate. 4. Composition for caring for the oral cavity according to claim 2, characterized in that the potassium salt of phosphoric acid is a mixture of potassium dihydrogen phosphate and dipotassium hydrogen phosphate. 5. Composition for caring for the oral cavity according to claim 4, characterized in that the mass ratio of potassium dihydrogen phosphate to dipotassium hydrogen phosphate is from 20: 1 to 1:10, preferably from 10: 1 to 1: 1. 6. Composition for caring for the oral cavity according to any of the preceding claims, characterized in that the potassium salt of phosphoric acid is present in an amount of 3 to 18%, preferably 5 to 10%, by weight of the composition. 7. Composition for caring for the oral cavity according to any of the preceding claims, characterized in that the calcium silicate is present in an amount of 0.1 to 50%, preferably 1 to 20%, by weight of the composition. 8. An oral composition according to any one of the preceding claims, characterized in that the calcium silicate and the tubule blocking enhancer are present in a weight ratio of 20: 1 to 1: 5, preferably 10: 1 to 1: 1. 9. Composition for caring for the oral cavity according to any of the preceding claims, characterized in that the composition contains calcium silicate and potassium salt of phosphoric acid in a mass ratio - 13 038664 wearing from 5: 1 to 1: 3. 10. An oral composition according to any of the preceding claims, wherein the composition further comprises a beneficial agent, preferably a particulate whitening agent. 11. An oral composition according to claim 10, wherein the particulate whitening agent is a composite particle, preferably the composite particle is titanium dioxide coated with calcium silicate. 12. An oral composition according to any one of the preceding claims, wherein the oral composition is a single phase, anhydrous composition. 13. Composition for caring for the oral cavity according to any one of claims 1 to 11, characterized in that the composition is a two-phase composition containing a calcium phase and a phosphate phase, wherein calcium silicate and a tubule blocking enhancer are present in the calcium phase, and the potassium salt phosphoric acid is present in the phosphate phase. 14. An oral composition according to claim 13, wherein the calcium phase and the phosphate phase are physically separate prior to application of the composition. 15. A method of desensitizing and / or remineralizing and / or whitening teeth of an individual, comprising the step of applying a composition according to any one of claims 1-14 to at least one surface of the teeth of an individual.