EA036533B1 - Oral care composition - Google Patents

Abstract

An oral care composition is disclosed comprising from 3 to 80 wt.% of calcium silicate, a soluble calcium source, a phosphate source and a physiologically acceptable carrier, wherein the calcium silicate and the soluble calcium source are present in a weight ratio from 1:3 to 20:1.

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, mouthwashes and the like. In particular, the present invention relates to an oral composition comprising calcium silicate and a soluble calcium source that results in desensitization and / or remineralization of teeth. The invention also relates to the use of such compositions for treating dental hypersensitivity and / or for remineralizing an individual's teeth.

Prior art

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

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

The currently accepted theory of dental hypersensitivity is a hydrodynamic theory based on the belief that exposed dentinal tubules provide fluid flow through the tubules. This stream excites nerve endings in the dental pulp. The clinical model of sensitive teeth, as observed by SEM (scanning electron microscopy), shows varying numbers of open or partially closed 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, including strontium ions, potassium salts such as potassium nitrate, potassium bicarbonate, potassium chloride, and the like. These nerve depolarizing agents act by interfering with neural transduction of pain stimulus to make the nerve less sensitive.

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

There is an ongoing need to treat dental hypersensitivity with a more effective approach. The present inventors have surprisingly found that an oral composition containing calcium silicate, a soluble calcium source and a phosphate source provides excellent tubule-blocking efficacy for desensitizing teeth. In addition, it was also found that such an oral care composition also exhibits excellent tooth remineralization efficacy.

Additional Information.

WO 2008/068149 A (Unilever) discloses an oral care product comprising a first composition comprising an insoluble calcium salt that is not a calcium phosphate salt, a second independent composition comprising a phosphate ion source, and a means for delivering each of the compositions to surfaces of teeth. The preferred insoluble calcium salt is calcium silicate.

The additional information above does not describe an oral composition containing 3 to 80 wt% calcium silicate, a soluble calcium source and a phosphate source, where the calcium silicate and the soluble calcium source are present in a weight ratio of 1: 3 to 20 : 1, and especially, such an oral composition can treat tooth hypersensitivity and / or increase the effectiveness of tooth remineralization.

Tests and definitions.

Means for cleaning teeth.

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 paste or gel 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 D50 particle size of a particulate material is the diameter of the particles at which 50 wt% of the particles are larger

- 1 036533 in diameter and 50 wt% less in diameter. For the purposes of the present invention, particle size and distribution are measured using a Malvern Mastersizer 2000 and a Malvern ZetaSizer Nano.

Precipitation agent.

A deposition agent, for the purposes of the present invention, means a material that facilitates the deposition of active substances, such as calcium silicate, and / or other beneficial agents from the continuous phase of the composition on the surface of the teeth during use of the composition. Beneficial agents used in this application means an active substance, usually delivered to human teeth and / or oral cavity, including the gums, to strengthen or improve the characteristics of these dental tissues.

pH.

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

Solubility.

Soluble and insoluble for the purposes of the present invention means the solubility of a source (eg, such as calcium salts) in water at 25 ° C and atmospheric pressure. Soluble means a source that dissolves in water to form a solution with a concentration of at least 0.1 mol / L. Insoluble means a source that dissolves in water to form a solution with a concentration of less than 0.001 mol / L. Therefore, sparingly soluble means a source that dissolves in water to obtain a solution with a concentration of more than 0.001 mol / L and less than 0.1 mol / L.

Hydration water.

Water of hydration 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, this means water, which can only be removed by heating above 200 ° C. Water loss is measured by thermogravimetric analysis (TGA) using a 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 more preferably even less than 0.5 wt%, and even more preferably less than 0.1 wt%, and most preferably 0.0 to 0.01 wt%, based on the total weight of the oral care composition, including all ranges encompassed therein.

Two-phase.

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 wt%, preferably 0.0 to 0.75 wt%, based on the total weight of the oral care composition.

Viscosity.

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

Remineralization.

Remineralization for the purposes of the present invention means the generation in situ (i.e., in the oral cavity) of calcium phosphate on teeth (including layers on teeth from 10 nm to 20 μm, preferably from 75 nm to 10 μm and most preferably from 150 nm to 5 μm thick, including all ranges pertaining thereto) to reduce the likelihood of tooth sensitivity, tooth decay, to regenerate enamel, and / or to improve the appearance of teeth by whitening by generating such new calcium phosphate.

Other terms.

Except for examples, or unless expressly indicated otherwise, all numbers in this description indicating the amount of material or reaction conditions, physical properties of materials and / or use, can be further understood as modified by the term about.

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

It should be noted that when specifying any ranges of values, any particular higher

- 2 036533 value can be associated with any specific lower value.

For the avoidance of ambiguity, the term containing means including, but not necessarily consisting of, or constructed from. In other words, the steps or options listed are not exhaustive.

The disclosure provided in this application is to be construed as covering all embodiments, as indicated in the claims, having multiple dependence on each other, regardless of the fact that the claims may be cited without multiple dependence or redundancy.

When a feature is disclosed in relation to a particular aspect of the invention (eg, a composition of the invention), such disclosure should also be considered in relation to any other aspect of the invention (eg, a method of the invention) mutatis mutandis.

Summary of the invention

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

a) 3 to 80 wt% calcium silicate;

b) a soluble calcium source;

c) a source of phosphate, and

d) a physiologically acceptable carrier;

where calcium silicate and soluble calcium source are present in a weight ratio of 1: 3 to 20: 1.

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

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

All other aspects of the present invention will become more 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, a soluble calcium source and a phosphate source can effectively seal open dentinal tubules, providing excellent tubule blocking performance to reduce tooth sensitivity. In addition, it was also found that such an oral care composition also exhibits excellent tooth remineralization efficacy.

Calcium silicate.

In a preferred embodiment, the calcium silicate used is CaSiO ₃ , which has low water solubility and is commercially available under the name Sorbosil CA40 from PQ Corporation. In another preferred embodiment, the 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 incorporated by links in their entirety. For a calcium silicate composite material, the ratio of calcium atoms to silicon atoms (Ca: Si) can be from 1:30 to 3: 1. The Ca: Si ratio is preferably from 1:20 to 2: 1, more preferably from 1:10 to 1: 1, and most preferably from about 1: 7 to 1: 1.5. Calcium silicate may contain mono-calcium silicate, di-calcium silicate or tri-calcium 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 preferable that the particles contain calcium oxide, silicon dioxide in an amount of at least 70 wt% by weight of the particles, more preferably at least 80 wt%, even more preferably at least 90 wt% and even more preferably at least at least 95 wt.%. Most preferably, the particles are composed of (or at least consist mainly 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 wt% calcium silicate hydrate, preferably at least 10 wt%, more preferably at least 15 wt%, even more preferably at least 20 wt% and most preferably at least 25 wt%. The water content usually does not exceed 50 wt%

- 3 036533 calcium silicate hydrate, more preferably does not exceed 40 wt%, even more preferably does not exceed 35 wt% and most preferably does not exceed 30 wt%.

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

To provide the calcium necessary for remineralization, the calcium silicate hydrate preferably contains calcium oxide in an amount of at least 5 wt% calcium silicate hydrate, more preferably at least 7 wt%, even more preferably at least 10 wt%, still more preferably at less than 12 wt%, and most preferably at least 15 wt%. The calcium oxide content is usually not more than 50 wt% based on the weight of the calcium silicate hydrate, more preferably not more than 40 wt%, even more preferably not more than 30 wt%, and most preferably not more than 25 wt%.

The calcium silicate hydrate preferably contains Ca and Si in an atomic ratio (Ca: Si) of less than 1: 1, more preferably less than 1: 1.2, 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. Calcium silicate is preferably particulate as this allows maximum surface area for contact with dental tissue. Thus, preferably the composition contains particles comprising calcium silicate. Preferably from 10 to 100%, especially from 25 to 100% and most preferably from 70 to 100% of the mass of the particles containing calcium silicate used in this invention have a particle size of from 100 nm to less than 50 μm, preferably from 500 nm to 30 μm, more preferably 1 to 20 μm, most preferably 3 to 15 μm.

In addition to calcium oxide, silicon dioxide and water, the particles that contain calcium silicate hydrate may contain other components such as metal cations, anions (such as phosphate), and the like. However, preferably, 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 consist mainly of) CaO, SiO ₂ and water.

Typically, the oral care composition of the present invention contains 3 to 80 wt% calcium silicate, more preferably 3 to 50 wt%, most preferably 5 to 30 wt%, based on the total weight of the care composition. behind the oral cavity and including all ranges related to it.

Soluble calcium source.

A soluble calcium source suitable for use in this invention is limited to the extent to which it can be used in the oral cavity.

Illustrative but non-limiting examples of the types of soluble calcium source that can be used in this invention include, for example, calcium chloride, calcium nitrate, calcium acetate, calcium lactate, calcium gluconate, calcium formate, calcium malate, calcium propionate, calcium butyrate, calcium bicarbonate, calcium glycerophosphate, calcium ascorbate, mixtures thereof, or the like. In a preferred embodiment, the calcium source is calcium chloride, calcium nitrate, or mixtures thereof.

Typically, the oral composition of the present invention contains from 0.1 to 20 wt% of a soluble calcium source, more preferably from 1 to 15 wt%, most preferably from 2 to 10 wt%, based on total weight compositions for the care of the oral cavity, including all ranges included therein.

The oral composition preferably contains calcium silicate and a soluble calcium source in a weight ratio of 1: 3 to 20: 1, more preferably 1: 3 to 10: 1, most preferably 1: 1.5 to 5: 1.

Phosphate source.

The source of phosphate that can be used in the present invention is limited only to the extent that it can be used in a composition suitable for use in the oral cavity. Illustrative examples of the types of phosphate source suitable for use in the present invention include trisodium phosphate, monosodium dihydrogen phosphate, disodium hydrogen phosphate, ammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, tripotassium phosphate, monopotassium dihydrogen phosphate, dipotassium hydrogen phosphate, or mixtures thereof, or the like thereof. The phosphate source is preferably a water-soluble source.

When used, the phosphate source is usually 0.5 to 40 wt%, and more preferably 1 to 30 wt%, and most preferably 2 to 20 wt%, based on the weight of the oral composition based on the total weight of the composition for care of the oral cavity, and including all ranges of 4 036533 zones related to it. In a preferred embodiment, the phosphate source used is trisodium phosphate and monosodium dihydrogen phosphate in a weight ratio of trisodium phosphate to monosodium dihydrogen phosphate from 1: 4 to 4: 1, preferably from 1: 3 to 3: 1 and most preferably from 1: 2 to 2: 1 , including all ranges related to them. In another preferred embodiment, the phosphate source used is or at least contains monosodium dihydrogen phosphate.

Optional components.

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 the enamel surface. Without wishing to be bound by theory, the present inventors believe that the presence of a soluble calcium source increases the concentration of calcium ions in the oral composition, which enhances the reaction between calcium salts and the oral phosphate source to form calcium phosphate. The deposition of calcium phosphate can promote the deposition of calcium silicate particles on the dentin and / or enamel surfaces. The calcium silicate can further interact with the phosphate source in saliva and / or the Si-OH groups of the calcium silicate can have an affinity for Ca ions in the teeth, further enhancing the tubular blocking efficiency and / or the tooth remineralization efficiency.

The composition for caring for the oral cavity according to the present invention may further comprise a deposition agent. The deposition agent suitable for use in this invention is limited only by the extent to which it can be used in the oral cavity. In a preferred embodiment, the deposition agent provides a large amount of calcium ions in the oral cavity and is inexpensive and readily available. In a particularly preferred embodiment, the precipitating agent is calcium salts in addition to the soluble calcium source that is included in the composition.

Illustrative, but not limiting examples of the types of precipitators that can be used in this invention include, for example, calcium sulfate hemihydrates, calcium dihydrogen phosphate, calcium aluminate, calcium monohydrogen phosphate, or mixtures thereof, or the like. In a preferred embodiment, the precipitating agent is calcium dihydrogen phosphate, calcium sulfate hemihydrate, or mixtures thereof.

The materials used as deposition agents in this invention have been found to be biocompatible and subject to rapid reaction with water and complete resorption to the tooth surface, so they can be used to aid in the deposition of oral care actives such as calcium silicate , and / or other beneficial agents on the tooth surface.

Typically, the oral composition of the present invention contains 0.1 to 20 wt% of a deposition agent, more preferably 0.2 to 15 wt%, even more preferably 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 related thereto.

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

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

Preferably, the composition for caring for the oral cavity contains a surfactant. Preferably, the composition contains at least 0.01 wt% surfactant by weight of the composition, more preferably at least 0.1 wt% and most preferably 0.5 to 7 wt%. 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 sulfosulfosuccinate) (sodium C8-C18 sulfoacetate) , 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 polyethoxylated sorbitan 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. Mixtures of any of the above materials can also be used. More preferably, the surfactant contains or is an anionic surfactant. Preferred anionic surfactants are sodium lauryl sulfate and / or sodium dodecylbenzenesulfonate. Most preferably, the surfactant is sodium lauryl sulfate.

A thickener can also be used in this invention and is limited only by the extent to which it can be added to a composition suitable for use in the oral cavity. Illustrative

- 5 036533 examples of the types of thickeners that can be used in this invention include sodium carboxymethyl cellulose (HCMC), hydroxy ethyl cellulose, methyl cellulose, ethyl cellulose, gum tragacanth, gum arabic, gum karaya, sodium alginate, carrageenan, ireland moheda, xena starch, modified starch, silica thickeners including silica aerogels, magnesium aluminum silicate (eg Veegum), carbomers (crosslinked acrylates), and mixtures thereof.

In general, xanthan gum and / or sodium carboxymethyl cellulose and / or carbomer are preferred. When carbomer is used, those are needed that have a weight average molecular weight of at least 700,000, and preferably those that have a molecular weight of at least 1,200,000, and most preferably those that have a molecular weight of at least about 2,500,000. The present invention may also mixtures of carbomers be used.

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

In another particularly preferred embodiment, the sodium carboxymethyl cellulose (SCMC) used is SCMC 9H. It has been described as a sodium salt of a cellulose derivative with carboxymethyl groups linked to the hydroxyl groups of the monomers of the glucopyranose framework and identified by CAS number 9004-32-4. It can be found from suppliers such as Alfa Chem.

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

The thickener is typically 0.01 to about 10 wt%, more preferably 0.1 to 9 wt%, and most preferably 1.5 to 8 wt%, based on the weight of the oral composition, based on the total weight of the composition and including all ranges related to it.

When the oral care composition of the present invention is a toothpaste or gel, it generally has a viscosity of about 30,000 to 180,000 cps, and preferably 60,000 to 170,000 cps, and most preferably 65,000 to 165,000 cps.

Suitable humectants are preferably used in the oral composition of the present invention and include, for example, glycerin, sorbitol, propylene glycol, dipropylene glycol, diglycerin, triacetin, mineral oil, polyethylene glycol (preferably PEG400); alkanediols such as butanediol and hexanediol; ethanol, pentylene glycol, or a mixture thereof. Preferred humectants are glycerin, polyethylene glycol, sorbitol, or mixtures thereof. The humectant can be present in the range of 10 to 90% by weight of the oral composition. More preferably, the humectant carrier comprises 25 to 80 wt%, and most preferably 45 to 70 wt% of the composition, based on the total weight of the composition, and including all ranges encompassed therein.

The oral composition of the present invention may contain a variety of other ingredients that are common in the art to enhance physical properties and performance. These ingredients include antimicrobial agents, anti-inflammatory agents, anti-caries agents, anti-plaque buffers, fluoride sources, vitamins, plant extracts, desensitizing agents, anti-tartar agents, biomolecules, flavors, proteinaceous materials, preservatives; opacity agents; colorants, pH adjusting agents, sweeteners, particulate abrasives, polymeric compounds, buffers and salts for buffering the pH and ionic strength of compositions and mixtures thereof. Such ingredients usually and together comprise less than 20 wt% of the composition, preferably 0.0 to 15 wt%, and most preferably 0.01 to 12 wt% of the composition, including all ranges encompassed therein.

The oral composition of the present invention can be used in a method for desensitizing and / or remineralizing a subject's teeth, comprising applying the composition to at least one surface of the subject's teeth. The oral composition of the present invention can additionally or alternatively be used for use as a medicament and / or used in the manufacture of a medicament for providing oral care as described herein, for example, to reduce sensitivity of an individual's teeth. Alternatively, and preferably, the use is not therapeutic.

Preferably, the oral composition is substantially free of water to prevent premature reaction between calcium salts and the phosphate source.

In a preferred embodiment, the oral composition is a single phase anhydrous composition.

In another preferred embodiment, the oral composition is a biphasic composition comprising a calcium phase and a phosphate phase, wherein the calcium silicate and a soluble calcium source are present in the calcium phase and the phosphate source is present in the phosphate phase. These 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 two-phase composition is fed using a double tube having a first calcium phase compartment and a second phosphate phase compartment, which allows the two phases to be co-extruded.

In a preferred embodiment, such a double tube has one of the compartments surrounding 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 a calcium phase and the shell is a phosphate phase.

In another preferred embodiment, such a double tube has two compartments adjacent to one and the same tube. In such embodiments, the two phases are extruded from the tube as one; such extrusion is called contact extrusion. The pump head can be used in such a double tube to bring two phases out of the tube as one.

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 device may include a cotton swab or spoon on which the calcium phase and phosphate phase are applied prior to bringing the spoon into contact with the teeth.

Typically, the composition will be packaged. In toothpaste or gel form, the composition can be packaged in a conventional plastic laminate, metal tube, or single chamber dispenser. It can also be applied to dental surfaces by any physical means such as a toothbrush, fingertip or applicator, directly on the sensitive area.

The composition can be effective even when used in an individual's daily oral hygiene routine. For example, the composition can be applied to the teeth with a brush. The composition may, for example, contact the teeth for a period of 1 second to 20 hours, more preferably 1 second to 10 hours, more preferably a further 10 seconds to 1 hour, and most preferably 30 seconds to 5 minutes. The composition can be used daily, for example, for use by an individual once, twice or three times a day. When the composition for caring for the oral cavity 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 3 minutes to 10 hours, more preferably 3 minutes to 8 hours. Application can be carried out daily.

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

Examples of

Example 1.

This example demonstrates improved dentinal tubule blockage using a soluble calcium source in combination with calcium silicate. All ingredients are expressed as wt% based on the total formulation and as active ingredient level.

Table 1

Ingredient Samples one 2 3 4 Calcium silicate ³ 15 ten ten ten Hydroxyapatite - 5 - - Calcium carbonate - - 5 - Calcium chloride - - - 5 Trisodium phosphate 3.8 3.8 3.8 3.8 Monosodium dihydrogen phosphate 3.2 3.2 3.2 3.2 Glycerol 78 78 78 78

a - commercially available calcium silicate (CaSiO ₃ ) from PQ Corporation (Sorbosil CA40).

Methods.

To evaluate the efficacy of dentinal tubule blockage, the test sample was mixed with water in a ratio of 1 g to 2 ml of water to obtain a suspension. Sample 1 containing only commercial calcium silicate was used as a control.

Human dentinal discs were eroded with 37% phosphoric acid for 1 min, after which they were treated with different suspensions by brushing according to the same protocol. Eight human dentinal discs were divided into four groups (n = 2). Dentin discs were brushed with suspension under a dental cleaning machine equipped with toothbrushes. The brushing load was 170 ± 5 g and the automatic brush was operated at 150 rpm. After brushing for 1 min, the dentin discs were soaked in the toothpaste suspension for 1 min. The dentinal discs were then rinsed with distilled water and placed in a simulated oral fluid (SOF) in a water bath with shaking at 37 ° C and 60.0 rpm. After soaking for about 3-4 hours, the dentin discs were machine-brushed with slurry using the same procedure as in the first step. The brushing was repeated three times over one day, then the dentinal discs were kept in SOF overnight (> 12 h) in a shaking water bath at 37 ° C to simulate the oral environment. The dentine specimens were brushed 7 times.

A simulated oral fluid was prepared by combining the ingredients shown in Table 2:

table 2

Ingredient Quantity, g NaCl 16.07 NaHCO ₃ 0.7 CS1 0.448 K ₂ HPO4 * 3H ₂ O 3.27 MgCl ₂ 0.0622 1MHC1 40 ml CaC1 ₂ 0.1998 Na ₂ SO ₄ 0.1434 Buffer Bring the pH to 7.0 Water Bring up to 2 l

Results.

After 7 brushings, SEM (Scanning Electron Microscopy) images of the dentin discs were obtained. This clearly showed that the dentinal tubules of dentinal discs treated with sample 4 containing a soluble calcium source were intensely blocked. For all other specimens, it can be seen that many of the dentinal tubules are still open.

Example 2.

This example demonstrates that the concentration of a soluble calcium source can influence the effectiveness of tubule blocking. All ingredients are expressed as wt% based on the total formulation and as active ingredient level.

Table 3

Ingredient Samples 5 6 7 8 nine Calcium silicate ³ 15 ten 5 3.33 - Calcium chloride - 5 ten 11.67 15 Trisodium phosphate 3.8 3.8 3.8 3.8 3.8 Monosodium dihydrogen phosphate 3.2 3.2 3.2 3.2 3.2 G lyserin 78 78 78 78 78

Table 4

Ingredient Samples 6 ten eleven Calcium silicate ³ ten thirty fifty Calcium chloride 5 5 5 Trisodium phosphate 3.8 3.8 3.8 Monosodium dihydrogen phosphate 3.2 3.2 3.2 Glycerol 78 58 38

Methods.

Sample preparation.

The same protocol was used to treat human dentin discs as described in Example 1. Dentin samples were brushed 3 and 7 times.

Counting standard for blocking channels.

Regardless of the original shape of the dentin discs, a square (4x4 mm) was selected and one image was acquired at 50x magnification. Within this square, five spots (each 150x150 μm, one in the middle and one in each corner) were selected and observed at 1000x magnification. Tubular blocking was evaluated according to the standards described in table. 5. Measurement was performed on two dentin discs from each test group.

Table 5

Scale indicator Tubule blocking 0 All dentinal tubules are open one <20% of dentinal tubules are completely blocked 2 20 to 50% of dentinal tubules are completely blocked 3 50 to 80% of dentinal tubules are completely blocked 4 80-100% of dentinal tubules are completely blocked 5 All dentinal tubules are completely blocked

Results.

After 3 and 7 brushings, SEM images of the dentinal discs were obtained. Images were analyzed and evaluated. The results are summarized in table. 6 (error represents standard deviation for duplicate measurements).

- 8 036533

Table 6

Tubular blockage 5 6 7 8 nine 3 brushes ^a 1.1 ^A ± 0.32 ^In 4,8 ± 0,42 3.6 ^s ± 0.70 1.4 ^A ± 0.52 1.2 ^A ± 0.42 7 treatments brush ^s 1.4 ^a ± 0.52 ^5.0 ± 0,00 ^In 4,8 ± 0,42 1.6 ^a ± 0.70 1.2 ^a ± 0.42

^a - values with different letters are significantly different (P <0.01); ^b - values with different letters are significantly different (P <0.01).

After 3 brushings, Sample 6, containing a combination of 5% calcium chloride and 10% calcium silicate, was shown to show significantly better tubule-blocking efficacy compared to Sample 7. Both Samples 6 and 7 showed increased tubule-blocking efficacy compared to Samples 5 and 9, including only calcium silicate or calcium chloride, respectively. Sample 8, containing a lower weight ratio of calcium silicate to calcium chloride, showed comparable tubular blocking efficiency with samples 5 and 9.

After 3 brushes, Sample 6 also showed comparable tubule-blocking efficacy compared to Samples 10 and 11, which contained more calcium silicate. SEM images clearly showed that nearly all of the dentinal tubules were intensely blocked.

After 7 brushes, samples 6 and 7 showed comparable tubule blocking efficiency. SEM images clearly showed that the dentinal tubules were intensely blocked, while for samples 5 and 9, part of the tubules were still open during this short treatment period.

Example 3.

This example demonstrates the effectiveness of dentinal tubule blocking for a variety of soluble calcium sources. All ingredients are expressed as wt% based on the total formulation and as active ingredient level.

Table 7

Ingredient Samples 12 13 Calcium silicate ³ ten ten Calcium chloride 5 - Ca (NO ₃ ) 2 * 4H ₂ O - 10.6 Trisodium phosphate 3.8 3.8 Monosodium dihydrogen phosphate 3.2 3.2 Glycerol 78 72.4

Methods.

The same protocol was used to assess the efficacy of blocking dentinal tubules as described in Example 1. The dentin samples were brushed 7 times.

Results.

After 7 SEM brushings, dentin disc images showed both samples 12 and 13 to have excellent tubular blocking performance. It can be seen that the dentinal tubules were intensely blocked.

Example 4.

This example demonstrates improved dentinal tubule blocking using a soluble calcium source in combination with calcium silicate in complete formulations. All ingredients are expressed as% by weight of the total composition and as active ingredient level.

Table 8

Ingredient Samples 14 15 16 G lyserin 64.84 64.84 64.84 Sodium monofluorophosphate 1, P 1, P 1, and Sodium saccharin 0.25 0.25 0.25 Calcium silicate ³ 15.00 10,00 10,00 Calcium chloride - 5.00 5.00 Calcium dihydrogen phosphate 2.00 2.00 - Sodium lauryl sulfate 2.00 2.00 2.00 Monosodium dihydrogen phosphate 3.20 3.20 3.20 Trisodium phosphate 3.80 3.80 3.80 Quartz abrasive ¹³ 6.00 6.00 6.00 Quartz abrasive ⁰ 0.50 0.50 0.50 Xanthan gum 0.10 0.10 0.10 Flavoring 1.20 1.20 1.20

^b - commercially available silicon dioxide under the trade name Sorbosil AC77 from PQ Corporation;

^c - commercially available silicon dioxide under the trade name Sorbosil AC43 from pq corporation.

Methods.

The same protocol was used to evaluate the efficacy of blocking dentinal tubules as described in Example 1. Dentin samples were brushed 3 and 7 times.

Results.

After 3 brushings, SEM images of the dentin discs were obtained. They showed that Samples 15 and 16, containing a soluble source of calcium such as calcium chloride, had a much better tubular blocking efficacy than Sample 14. Sample 15 through 9 036533 showed comparable tubular blocking efficacy to Sample 16, which additionally contains calcium dihydrogen phosphate.

After 7 brushings, all three samples showed similar results, the dentinal tubules were intensely blocked. But the corresponding cross-sectional SEM images after 7 brushings showed that for samples 15 and 16, materials penetrated deep into the dentinal tubules and the tubules were completely filled. At the same time, for sample 14, materials were only deposited over the dentinal tubules in this short processing period.

Example 5.

This example demonstrates improved deposition on a tooth surface using a soluble calcium source in combination with calcium silicate in complete compositions. The samples used here were samples 14-16, as indicated in example 4.

Methods.

To assess the deposition on the surface of the teeth, the test sample was mixed with water in a ratio of 1 g to 2 ml of water to obtain a suspension of toothpaste.

Blocks of bovine enamel were treated with different suspensions by brushing according to the same protocol. Blocks of enamel were brushed with the slurry under a dentifrice machine equipped with toothbrushes. The load on the toothbrush was 170 ± 5 g and the automatic brush was operated at 150 rpm. After brushing for 1 min, the enamel blocks were soaked in the toothpaste suspension for 1 min. Then the enamel blocks were washed with distilled water and placed in SOF in a water bath with shaking at 37 ° C and 60.0 rpm. After soaking for about 3-4 hours, the enamel blocks were processed with the slurry by means of a machine using the same procedure as in the first step. The brushing was repeated three times in one day, then the enamel blocks were stored in SOF overnight (> 12 h) in a water bath with shaking at 37 ° C to simulate an oral environment. Blocks of enamel were brushed 14 times.

Results.

After 14 brushings, SEM images of the enamel block surfaces were obtained. It was evident from the top view of the SEM images that Samples 15 and 16 gave better and denser deposition on the tooth surface than Sample 14. The corresponding cross-sectional SEM images further showed that a new layer was formed on the enamel surface of the blocks after treatment with Samples 15 and 16, while the blocks of enamel treated with Sample 14 had no layer formed on their surfaces in this short processing period. Analysis using EDX (Energy Dispersive X-ray Spectroscopy) identified the elements Si, Ca and P in the new layer, indicating that calcium silicate is deposited on the tooth surface and induces remineralization.

Example 6.

This example demonstrates the effect of the concentration of a soluble calcium source in complete formulations on the effectiveness of dentinal tubule blocking. All ingredients are expressed as% by weight of the total composition and as active ingredient level.

Table 9

Ingredient Samples 17 eighteen 19 twenty Glycerol 70.84 68.84 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 10,00 10,00 10,00 10,00 Calcium chloride 1.00 3.00 5.00 7.00 Sodium lauryl sulfate 2.00 2.00 2.00 2.00 Monosodium dihydrogen phosphate 3.20 3.20 3.20 3.20 Trisodium phosphate 3.80 3.80 3.80 3.80 Quartz abrasive ^b 6.00 6.00 6.00 6.00 Quartz abrasive ⁰ 0.50 0.50 0.50 0.50 Xanthan gum 0.10 0.10 0.10 0.10 Flavoring 1.20 1.20 1.20 1.20

Methods.

The same protocol was used to evaluate the effectiveness of blocking dentinal tubules as described in Example 1. Dentin specimens were brushed 3 times.

Results.

After 3 brushings, SEM images of the dentinal discs were obtained. Sample 18, containing 3% calcium chloride, showed much better tubule blocking efficacy compared to Sample 17 containing only 1% calcium chloride. In top view SEM images, the dentinal tubules were nearly blocked. Samples 19 and 20, containing a higher concentration of calcium chloride, showed even better tubular blocking efficacy.

Example 7.

This example demonstrates the effect of the concentration of a soluble calcium source in complete compositions on deposition on the tooth surface. The samples used here were samples 1720, as indicated in example 6.

- 10 036533

Methods.

The same protocol was used to assess deposition on the tooth surface as described in Example 5. The enamel blocks were brushed 3 times.

Results.

After 3 brushings, SEM images of the enamel block surfaces were obtained. The top view SEM images show that all samples showed good deposition on the tooth surface. But samples 18-20, containing a higher concentration of calcium chloride, showed better and denser deposition on the tooth surface than sample 17. The corresponding cross-sectional SEM images further showed that a new layer was formed on the surface of the enamel blocks after treatment with samples 18- 20, while the blocks of enamel treated with Sample 17 had no layer formed on their surfaces in this short processing period.

Example 8.

This example demonstrates the affinity of the newly formed layer on the surfaces of the teeth. The samples used here were Sample 14 in Example 4 and Sample 18 in Example 6. All ingredients are expressed as wt% based on total formulation and as active ingredient level.

Table 10

Ingredient Samples 14 eighteen Glycerol 64.84 68.84 Sodium monofluorophosphate 1.11 1, and Sodium saccharin 0.25 0.25 Calcium silicate ³ 15.00 10,00 Calcium chloride - 3.00 Calcium dihydrogen phosphate 2.00 - Sodium lauryl sulfate 2.00 2.00 Monosodium dihydrogen phosphate 3.20 3.20 Trisodium phosphate 3.80 3.80 Quartz abrasive ^b 6.00 6.00 Quartz abrasive ⁰ 0.50 0.50 Xanthan gum 0.10 0.10 Flavoring 1.20 1.20

Methods.

To assess the affinity of the newly formed layer on the surfaces of the teeth, the test sample was mixed with water in a ratio of 1 g to 2 ml of water to obtain a suspension of toothpaste.

Blocks of bovine enamel were treated with different suspensions by brushing according to the same protocol. Blocks of enamel were brushed with the slurry under a dentifrice machine equipped with toothbrushes. The load on the toothbrush was 170 ± 5 g and the automatic brush was operated at 150 rpm. After brushing for 1 min, the enamel blocks were soaked in the toothpaste suspension for 1 min. Then the enamel blocks were washed with distilled water and placed in SOF in a water bath with shaking at 37 ° C and 60.0 rpm. After soaking for about 3-4 hours, the enamel blocks were brushed with water using a dentifrice machine. The load on the toothbrush was 170 ± 5 g and the automatic brush was operated at 150 rpm. After brushing for 1 minute, the blocks of enamel were placed in SOF under the condition of a water bath with shaking at 37 ° C and 60.0 rpm. After soaking for about 3-4 hours, the enamel blocks were rinsed again with water, again using the dentifrice machine for 1 minute (load 170 ± 5 g, 150 rpm). The enamel blocks were then brushed with fresh toothpaste using a dentifrice machine for 1 min (load 170 ± 5 g, 150 rpm) and soaked in the toothpaste suspension for 1 min. The enamel blocks were then washed with distilled water and stored in SOF overnight (> 12 h) in a shaking water bath at 37 ° C to simulate an oral environment. The enamel blocks were then rinsed with water using a dentifrice machine for 1 min (load 170 ± 5 g, 150 rpm). These stages are considered to be a whole processing cycle of one day. The enamel blocks were processed for 7 days.

Results.

After 7 days of processing, SEM images of the surfaces of the enamel block were obtained. Top view SEM images show that Sample 18 showed better and denser deposition on the tooth surface than Sample 14.

Corresponding cross-sectional SEM images further showed that a new layer was formed on the surfaces of the enamel blocks after treatment with sample 18, while the enamel blocks treated with sample 14 had no layer formed on their surfaces in this short processing period. The results clearly showed that the newly formed layer was not brushed away, indicating an increased affinity of the newly formed layer on the tooth surfaces. A section of the newly formed layer was collected by FIB (Focused Ion Beam) and then placed on a TEM (Transmission Electron Microscopy) grating for characterization by SAED (Selected Electron Diffraction) and EDX. EDX analysis identified the elements Si, Ca and P in the new layer, indicating that calcium silicate was deposited on

- 11 036533 tooth surfaces and induces remineralization. It was clearly seen from the SAED electron diffraction diagram that the newly formed layer on the enamel blocks was hydroxyapatite (HAP).

Claims (15)

CLAIM 1. Composition for the care of the oral cavity containing: a) 3 to 80 wt% calcium silicate; b) a soluble calcium source; c) a source of phosphate, and d) a physiologically acceptable carrier; where calcium silicate and a soluble calcium source are present in a weight ratio of 1: 3 to 20: 1. 2. An oral care composition according to claim 1, wherein the soluble calcium source is calcium chloride, calcium nitrate, calcium acetate, calcium lactate, calcium gluconate, calcium formate, calcium malate, calcium propionate, calcium butyrate, calcium bicarbonate, calcium glycerophosphate, calcium ascorbate or mixtures thereof, preferably calcium chloride, calcium nitrate or mixtures thereof. 3. An oral composition according to claim 1 or 2, wherein the phosphate source is water-soluble. 4. An oral composition according to any one of the preceding claims, wherein the calcium silicate is a calcium silicate hydrate that includes hydration water in an amount of 5 to 50% by weight of calcium silicate hydrate. 5. An oral composition according to any one of the preceding claims, wherein the calcium silicate is present in an amount of 3 to 50 wt% of the composition, preferably 5 to 30 wt%. 6. An oral composition according to any one of the preceding claims, wherein the calcium silicate and the soluble calcium source are present in a weight ratio of 1: 3 to 10: 1, preferably 1: 1.5 to 5: 1. 7. Composition for caring for the oral cavity according to any one of the preceding claims, in which the source of phosphate is trisodium phosphate, monosodium dihydrogen phosphate, disodium hydrogen phosphate, ammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, tripotassium phosphate, monopotassium dihydrogen phosphate, or a mixture thereof; preferably trisodium phosphate, monosodium hydrogen phosphate, or a mixture thereof. 8. An oral composition according to any one of the preceding claims, wherein the phosphate source is present in an amount of 0.5 to 40 wt% of the composition, preferably 1 to 30 wt%. 9. An oral composition according to any one of the preceding claims, further comprising a deposition agent selected from calcium dihydrogen phosphate, calcium sulfate hemihydrates, calcium aluminate, calcium monohydrogen phosphate, or mixtures thereof. 10. An oral composition according to claim 9, wherein the precipitating agent is calcium dihydrogen phosphate. 11. An oral composition according to claim 9 or 10, wherein the calcium silicate and the precipitating agent are present in a weight ratio of 10: 1 to 1: 1. 12. Composition for caring for the oral cavity according to any of the preceding claims, which is a single phase anhydrous composition. 13. Composition for caring for the oral cavity according to any one of the preceding claims 1 to 11, which is a two-phase composition containing a calcium phase and a phosphate phase in which calcium silicate and a soluble calcium source are present in the calcium phase and the phosphate source is present in the phosphate phase ... 14. An oral composition according to claim 13, wherein the calcium phase and the phosphate phase are physically separated prior to use of the composition. 15. A method for remineralizing an individual's teeth, comprising the step of applying a composition according to any one of claims 1-14 to at least one surface of the individual's teeth.