WO2010018167A1

WO2010018167A1 - Dental formulations for the prevention of dental erosion

Info

Publication number: WO2010018167A1
Application number: PCT/EP2009/060376
Authority: WO
Inventors: Allan Bardow Jensen; Maja Bruvo Lazovic
Original assignee: Københavns Universitet
Current assignee: Københavns Universitet
Priority date: 2008-08-12
Filing date: 2009-08-11
Publication date: 2010-02-18
Anticipated expiration: 2011-02-12
Also published as: EP2341985A1

Abstract

The invention relates to a therapeutic method for preventing and/or inhibiting dental erosion in a mammalian subject, and the provision of a dental care product for performing the method. The dental care product of the invention comprises a starch-degrading enzyme of E. C. 3.2.1.1, wherein said product comprises less than 1 wt.% ionic surfactant, and preferably is substantially free of endoprotease and/or lipase. The properties of the dental care product serve to prevent and/or inhibit dental erosion in a subject that typically results from repeated exposure of the patient's tooth surfaces to acids, which may originate from food, drinks, or gastric juice.

Description

Title: Dental formulations for the prevention of dental erosion

Technical field of the invention

The invention relates to the provision of a dental care product for preventing and/or inhibiting dental erosion in a mammalian subject that typically arises as a result of repeated exposure of tooth surfaces to acids, which may originate from food, drinks, or gastric juice.

Background of the invention Dental erosion is chemical wear of teeth without involvement of bacteria (Eccles, 1979). This condition can cause a progressive loss of dental hard tissue (enamel or dentine) and is often characterised by being evenly distributed over the whole surface of the involved teeth. Dental erosion develops after repeated exposure of tooth surfaces to acids, which may originate from food, drinks, or gastric juice. In contrast, dental caries is caused by acid producing bacterial deposits on poorly cleaned areas on tooth surfaces. Therefore dental caries result in much more localised loss of enamel or dentine that may develop into cavities and tooth decay, which need dental treatment in the form of fillings or crowns. Soft drink consumption seems to be the most common source of acid for dental erosion (Jensdottir et al., 2004). However, acidic solid or semisolid foodstuffs as well as gastric juice, which may enter the mouth as a result of vomiting or reflux diseases, are also major contributors to the development of dental erosion (Jarvinen et al., 1991 ). For all causes of dental erosion, the frequency of acid exposure seems to be especially important, although the chemical (Jensdottir et al., 2006) and physical properties of foodstuffs (Ireland et al., 1995), as well as individual factors such as low saliva flow rate (Jarvinen et al., 1991 ), and special drinking habits (Johansson et al., 2004), also play a modifying role. In contrast to dental caries, the prevalence of dental erosion seems to be increasing, especially among children (Nunn et al., 2003) and young people (Jensdottir et al., 2004), and therefore dental erosion currently attracts much attention in dental research and in the general public.

In response to the increased prevalence and awareness of dental erosion, several preventive measures aimed at reducing dental erosion have been developed. These include modification of acidic foodstuffs, additives to dentifrices, and special fluoride vanishes for application by a dental practitioner. Although some of these techniques are on the market now, most of them may still be experimental at the moment. Thus, the most effective measure so far seems to be information programs aimed at reducing the intake of acidic foodstuffs. Modification of highly erosive foodstuffs such as soft drinks (i.e. the ones with the lowest pH) by employing calcium and phosphate salts is unrealistic, since this can adversely affect their taste. Coating of tooth surfaces with vanishes that increase the acid resistance of teeth may only confer protection for a short time, and therefore fail to prevent erosion when the acidic substance is introduced onto the tooth surface.

Because the acids involved in the development of dental erosion do not originate from bacteria on the tooth surfaces, tooth brushing will not prevent dental erosion. On the contrary tooth brushing may accelerate dental erosion if performed shortly after intake of acidic foodstuffs (Attin et al., 2001 ). Thus, the combination of mechanical forces from toothbrushing working together with the chemical weakening of the tooth surface caused by acidic foodstuffs strongly accelerates the loss of tooth substance and results in increased dental wear compared to either of the two processes alone. If toothbrushing is performed before the intake of acidic foodstuffs it may also influence the development of dental erosion. In vivo tooth surfaces that are not brushed will normally become covered in a layer of bacteria also known as dental plaque, which may act as protection against acid from foodstuffs. Furthermore, toothpaste often contains detergents, which may expose or prime the inorganic components of the teeth to acid demineralisation (Rykke et al., 1990). Accordingly, toothbrushing makes teeth become more susceptible to acids from foodstuffs and soft drinks.

In this perspective one may therefore say that it is better not to brush ones teeth than to brush them. However, as tooth-brushing is the main preventive measure against dental caries, which still is the main cause of tooth loss worldwide, tooth-brushing cannot be avoided or realistically replaced by other measures. There exists therefore a need for dental formulations that can protect against dental erosion. EP1568356A1 describes the use of colostrum protein in a dental care product to prevent dental erosion. WO2006/016803 describes the use of a functional milk fraction in a dental care product to prevent dental erosion where the protective activity is attributed to a low molecular weight nitrogen fraction of milk or whey, being neither lactose nor the mineral fraction. WO2005/110347 describes the use of hydrofluoric acid at concentrations of 0.05-2.00% at a pH of 2.5-4.5 in a dental care product to prevent dental erosion. The long-term effects and the clinical significance of adding such erosion-preventing substances to dentifrice are, however, still largely unknown.

Summary of the invention

The claimed the invention relates to the use of a starch-degrading enzyme of E. C. 3.2.1.1 for the manufacture of a dental care product for preventing and/or inhibiting dental erosion, wherein said product comprises less than 1 % ionic surfactant by weight. Preferably the product is substantially free of endoprotease and optionally is also substantially free of lipase. According to one embodiment of said use, the dental care product is a toothpaste, tooth gel, tooth powder, denture cleaning agent, mouthwash, lozenge or chewing gum.

According to a second embodiment of said use, the dental care product is dental floss or a toothpick.

According to a further embodiment of said use, wherein the starch- hydrolyzing enzyme is alpha-amylase (α-amylase) of bacterial or fungal origin.

According to a further embodiment of such use, the starch-hydrolyzing enzyme comprises from 0.1 % to 20% weight by weight of the dental care product.

According to a further embodiment of said use, the dental care product further comprises one or more of an abrasive polishing material, whitening agent, flavoring agent, humectant, binder, thickener, and/or sweetener.

According to a further embodiment of said use, the dental care product further comprises one or more fluoride-ion releasing agent that is an inorganic fluoride salt selected from a soluble alkali metal and an alkaline earth metal salt.

According to a further embodiment of said use, the dental care product further comprises one or more fluoride-ion releasing agent in an amount sufficient to release 300 to 2,000 ppm of fluoride ions by weight of the dental care product. According to a further embodiment of said use, the dental care product further comprises zinc ions in an amount in the range of 0.0025 - 0.15 % by weight of the dental care product

According to a further embodiment of said use, the dental care product further comprises a non-ionic surfactant in an amount not exceeding 15% by weight of the dental care product.

The claimed invention further relates to a dental care product for preventing and/or inhibiting dental erosion comprising a starch-degrading enzyme of E. C. 3.2.1.1 , wherein said product comprises less than 1 % ionic surfactant by weight. In a preferred embodiment the product is substantially free of endoprotease and optionally is also substantially free of lipase.

According to one embodiment, said dental care product is a toothpaste, tooth gel, tooth powder, denture cleaning agent mouthwash, lozenge or chewing gum.

According to a second embodiment, said dental care product is dental floss or a toothpick.

According to a further embodiment of said dental care product, the starch- hydrolyzing enzyme is alpha-amylase of bacterial or fungal origin.

The claimed invention further relates a method of preventing and/or inhibiting dental erosion in a mammalian subject, comprising the steps of: (a) contacting the dental care product of the invention with the teeth and/or gums of the subject for between about 30 seconds to 15 minutes; wherein said contact is combined with brushing, chewing and/or rinsing. Detailed description of the figures

Figure 1. Changes in surface microhardness values (SMH) of sound and healthy polished bovine enamel blocks (1 cm²) after 30 minutes of exposure to 50 ml_ of Type I water containing the anionic detergent SLS at concentrations ranging between 1 and 5 percent (w/v). Figure 2. Protective effect against acid-induced enamel softening of pellicles developed from solutions of 0.5% w/v human whole saliva proteins (saliva) on bovine enamel. Natural protective effect of a pellicle developed from incubation with 0.5% w/v human whole saliva proteins (saliva only), effect of pre-treatment of the enamel surface with a 2% SLS solution prior to pellicle formation (SLS-Saliva), effect of treatment of the enamel surface with a 2% SLS solution after pellicle formation (Saliva- SLS), in each case immediately followed by acid exposure. Figure 3. The relation between the concentration of α-amylase in samples of human parotid saliva from different individuals and the protective effect of pellicles developed from the same saliva against acid-induced enamel surface softening. Figure 4. Differences in protective effects of the industrially produced α- amylases: BAN, Fungamyl, Liquozyme, and Termamyl, which all were obtained from NOVOZYMES, against acid-induced enamel surface softening. For comparison the protective effects of human parotid saliva, human whole saliva, and bovine colostrum protein are also shown. Figure 5. Enamel surface microhardness (kp/mm²) of bovine enamel after acid-induced softening for 5 minutes. Prior to the acidic challenge the enamel was immersed in aqueous solutions of different fluoride toothpastes. Toothpaste I was regular toothpaste containing SLS, toothpaste Il was regular toothpaste where SLS was replaced by a non- ionic detergent, and toothpaste III was similar to Il except for the addition of 3.0% of commercial amylase. Detailed description of the invention

The present invention seeks to prevent or inhibit the process of dental erosion and thereby preserve dental hard tissue in the oral cavity of a subject.

Surprisingly we have found that the human salivary α-amylase, when incorporated into a dental pellicle on an enamel surface, is able to protect the enamel against demineralisation during an acid exposure. As shown in Figure 3, the concentration of α-amylase in samples of human parotid saliva from different individuals showed a significant correlation (r=0.65; p<0.01 ) with the protective effect of pellicles developed during 30 min on bovine enamel from that same saliva. Thus, bovine enamel that was coated with parotid saliva having a high α-amylase concentration was able to maintain its surface microhardness better than enamel that was coated with saliva samples having a lower amylase concentration. Among 25 different salivary proteins present in the tested saliva samples, α-amylase was the only protein whose abundance could be directly related to the protective effect of the samples against an acid exposure. Therefore α- amylase in a dental care product can be used for prevention and/or inhibition of the process of dental erosion. Thus, as shown in Figure 4, industrially produced α-amylases of bacterial, as well as fungal origin posses the same ability to coat and protect enamel surfaces against the demineralisation that occurs during an acid exposure. Therefore, a toothpaste containing α-amylase can protect the teeth better than regular toothpaste without amylase (Figure 5).

While not wishing to be bound by theory, it is thought that the starch- hydrolysing enzyme, amylase, when provided in a dental composition, binds to the surface of teeth contributing to the creation and maintenance of a protective protein layer on their surfaces. In this manner the natural protein layer on the surface of teeth, i.e. the pellicle, is restored and preserved. The conservation of a protective protein layer on the teeth, brought about by the additional bound amylase, protects the underlying dental hard tissue from acid erosion. Amylase, in the dental care product of the invention, not only contributes to the preservation of the pellicle, but also catalyses the degradation of starch in food debris present in the oral cavity and deposited on the tooth surface. In this manner, a dental care product comprising amylase, acts together with salivary amylases as a natural detergent in the oral cavity, by selectively degrading starch while leaving the protective protein layer intact on the surface of the teeth after dental care e.g. brushing. In this manner, the dental care products of the invention largely eliminate the need for strong anionic detergents (e.g. sodium lauryl sulphate; SLS), in toothpaste, which are otherwise employed to clean teeth and the oral cavity. Such strong ionic detergents serve to strip off food debris. Unfortunately, as shown in Figure 1 and 2, strong anionic detergents have the capacity to make the enamel surface vulnerable to acid erosion by interfering with the formation of the protective pellicle and thereby increasing the vulnerability of the tooth surface following tooth brushing. Also strong anionic detergents like SLS can bind cations, which in the case of calcium can cause decreased protection of the dental tissues, reduced binding of fluoride in the oral environment, increased solubility of calcium fluoride, and decreased formation of calcium fluoride on tooth surfaces following toothbrushing (Barkvoll et al., 1988). With respect to dental caries it seems that the importance of these side effects of SLS are of minor importance. However, we propose that with respect to dental erosion, the effects of depletion of calcium ions from the microenvironment near the tooth surfaces and decreased calcium fluoride formation may be much more important. Thus, eliminating or reducing the need for ionic detergents (particularly anionic detergents) in the dental care products of the invention serves to avoid or greatly minimise binding of calcium ions and the loss and inhibition of renewal of the protein protective layer, and thereby protects teeth from the erosive effects of acid exposure. Enzymes, such as endoproteases and/or lipases, which may interfere with the formation of the protective pellicle, by degrading proteins and/or lipoproteins in this protective layer, are preferably to be avoided. In this perspective, the invention serves to provide the tooth surface after tooth brushing with a protein layer protection comparable to the protection it had before tooth brushing.

The term "dental erosion" is the process whereby dental hard tissue (i.e. enamel and dentine) is eroded by acids that are not produced by bacteria in the dental plaque. Dental erosion can be specifically measured by clinical examination of teeth, comparison of plaster or acrylic dental casts of the same teeth made at different time points, profilometric scanning of tooth surfaces, microradiography, and loss of minerals from tooth surfaces exposed to eroding fluids. The erosive potential or effect of different fluids can also be determined indirectly as changes in surface microhardness of enamel or dentine by the Knoop or Vickers microhardness tests [Hannig et al., 2004].

The term "dental caries" is the process whereby dental hard tissue (i.e. enamel and dentine) is demineralised, and eventually decayed due to caries lesion formation, by acids that are produced by bacteria in the dental plaque. Dental caries can be specifically measured by visual examination of teeth including air-drying and probing, by x-ray examination, by microradiography, by colorimetric methods that include colouring of decayed dentine, by various photometric methods including quantitative fluorescence (QLF) and polarised light, and by electrical methods (electrical caries measurement - ECM). The two processes can thus be clearly distinguished in that dental erosion leads to loss of dental hard tissue over large areas of the surfaces of teeth due to acid induced erosion; while dental caries is characterised by a localised loss of dental hard tissue from a tooth due to bacterial induced demineralisation detectable as localised pits or cavities in the tooth surface.

The invention provides a dental care composition that comprises at least one starch-hydrolysing enzyme in an amount sufficient to prevent dental erosion, but comprises less than 1 wt.% (more preferably between 0 and 0.5 wt.%) ionic detergents. Preferably the product is substantially free of ionic detergents and the enzymes: (endo)proteases and/or lipases. Furthermore, the dental composition and the dental care product may contain fluoride and antimicrobial agents for prevention of demineralisation, enhancement of remineralisation and to control bacterial growth.

The term "substantially free" with respect to both of the compounds: (endo)protease and/or lipase in the dental care composition of the invention, shall be understood as requiring that intentional inclusion of any of these compounds in the manufactured composition is avoided, and that unintentional contamination of the composition is preferably kept below a level detectable using standard analytical procedures known to the skilled man, or at least at a level lying below that required for the functional properties of the compound to be detectable in the composition.

The term "starch-hydrolysing enzyme" in the context of the present application refers to the enzyme, α-amylase (E. C. 3.2.1.1 ), which functions to hydrolyse linkages in starch. The α-amylase, may be a bacterial α- amylase, such as BAN™ or Maltogenase™ (both available from Novo Nordisk), or an α-amylase derived from Bacillus subtilis; an α-amylase derived from Bacillus amyloliquefaciens; an α-amylase derived from Bacillus stearothermophilus; an α-amylase derived from Aspergillus oryzae; or an α-amylase derived from a non-pathogenic microorganism. The α-amylase may also be a fungal α-amylase, such as Fungamyl™, which is available from Novo Nordisk.

The term "ionic surfactant" or "ionic detergent" in the context of the present application comprise both: An ionic-detergents or anionic-surfactants (including soap and the largest portion of modern synthetic detergents), which produce electrically negative colloidal ions in solution; and cationic- detergents or cationic-detergents, containing a long-chain cation, which produce electrically positive ions in solution.

The term (endo)protease in the context of the present application means: a protease enzyme that attacks and cleaves internal peptide bonds of a protein (e.g. trypsin, chymotrypsin, pepsin, papain, elastase).

The term lipase in the context of the present application means: a water- soluble enzyme that catalyzes the hydrolysis of ester bonds in water- insoluble, lipid substrates, and for example act to convert triglyceride substrates found in oils from food to monoglycerides and free fatty acids.

The invention further provides a "dental care product" comprising the dental care composition of the invention. A "dental care product" is defined as a product, which can be used for preventing or inhibiting dental erosion, which also serves to maintain and/or improve oral hygiene in the mouth of a human and animal subject, and/or preventing or inhibiting dental caries. The amount of starch-hydrolysing enzyme in the dental composition depends on the "dental care product" to be prepared. Generally a dental composition and the dental care product will contain said enzyme in an amount that lies within the range of from 0.0001 wt.% to 20 wt.%, preferably from 0.1 wt.% to 5 wt.%, more preferably from 1 wt.% to 3 wt.% Furthermore, both the dental composition and the dental care product comprise less than 1 % (more preferably between 0 and 0.5%) ionic detergents, and are preferably substantially free of (endo)proteases and/or lipases.

Examples of such dental care products of the invention include a toothpaste, dental cream, gel or tooth powder, odontic, mouthwash, denture-cleaning agent, pre- or post-brushing rinse formulation, chewing gum and lozenge. A dental care product may also be in the form of a dental floss or toothpick. Where the dental care product is a toothpaste (including a tooth gel, tooth powder and dental tablet), further components of the product typically include one or more of an abrasive or polishing material, whitening agent, antibacterial protein, foaming agent, flavouring agent, humectant, binder, thickener, sweetener, neutralising agent, herbal extracts or the like, remineralising compounds, and water.

Where the dental care product is a mouthwash, further components typically comprise one or more of a water/alcohol solution, a flavouring agent, humectant, sweetener, foaming agent, herbal extracts or the like, remineralising compounds, and colorant.

Where the dental care product is a chewing gum, the product may be prepared by incorporating one or more starch-hydrolysing enzyme into a conventional chewing gum base, e.g. jelutone, rubber lates, vinylite resins preferably in combination with conventional plasticisers or softeners, natural and/or artificial sweeteners, flavourings, etc. as desired. Preparation of the chewing gum may involve stirring any of the components of the chewing gum formulation into a warm gum base, or coating the outer surface of the gum base. Upon addition of the enzyme(s) to the gum base, the temperature of the gum base should preferably not exceed 60° C, more preferably not exceed 50° C.

Toothpaste of the invention may be substantially solid or pasty and comprise one or more of an abrasive or polishing material such as: alumina and hydrates thereof, such as alpha alumina trihydrate; magnesium trisilicate, magnesium carbonate; sodium bicarbonate ("baking soda"); kaolin; aluminosilicates, such as calcined aluminium silicate and aluminium silicate; calcium carbonate; zirconium silicate; silica xerogels, hydrogels and aerogels and the like. Also suitable as abrasive agents are calcium pyrophosphate, water-insoluble alkali metaphosphates, dicalcium phosphate and/or its dihydrate, dicalcium orthophosphate, tricalcium phosphate, particulate hydroxyapatite. Preferred polishing materials include silica gel or colloidal silica having particle sizes between 1 and 20 microns, preferably between 1 and 10 microns.

Additional polishing agents may include powdered synthetic plastic materials such as polyvinyl fluoride, polyvinyl chloride, polyamides, polymethyl methacrylate, epoxy resins, powdered polyethylene, polystyrene, phenol-formaldehyde resins, aminoplasts such as urea- or melamine-formaldehyde-condensates (having a particle size of between about 0.5 and about 40 microns, preferably between about 1 and about 20 microns). Additional polishing agents may also include bioactive glass such as NovaMin® that could add to the erosion protecting effects of the toothpaste.

The abrasive material content typically lies in the range from 10% to 75% by weight when the final dental product is toothpaste; and from 70% to 99% by weight, when it is a tooth powder. In toothpaste, the liquid vehicle may comprise water and a humectant, which is employed to prevent loss of water. Suitable humectants for use in a dental care product according to the invention include one or more of: glycerol, polyol, sorbitol, polyethylene glycols (PEG), propylene glycol, 1 ,3- propanediol, 1 ,4-butane-diol, and hydrogenated partially hydrolysed polysaccharides. Humectants are in general present in an amount of from 0% to 80%, preferably 5 to 70% by weight in toothpaste.

In toothpaste, suitable thickeners and binders which help stabilize the dental care product are silica, starch, tragacanth gum, xanthan gum, extracts of Irish moss, alginates, pectin, cellulose derivatives, such as hydroxyethyl cellulose, sodium carboxymethyl cellulose and hydroxy- propyl methyl cellulose, hydroxy-butyl methyl cellulose, polyacrylic acid and its salts, and polyvinyl-pyrrolidone. Thickeners may be present in toothpastes and gels in an amount of from 0.1 to 20% by weight, and binders in an amount of from 0.01 to 10% by weight of the final product.

Suitable sweeteners for use in dental care products of the invention include lactose, maltose, sorbitol, xylitol, sodium cyclamate, perillartine, APM (aspartyl phenyl alanine methylester) saccharin and/or other sweeteners.

Suitable flavouring agents for use in dental care products of the invention are oils, including oil of spearmint, peppermint, wintergreen, sassafras, clove, sage, eucalyptus, majoram, cinnamon, lemon and orange. These sweeteners and flavouring agents may together comprise from 0.01 % to about 5% by weight, especially from 0.1 % to 5% of a dental care product.

Suitable foaming agents for use in dental care products of the invention are limited to surfactants (detergents) that do not significantly solubilise the protein protective layer of the teeth, and also do not exert any adverse effect on the activity of the starch-degrading enzyme in the dental composition. Accordingly, suitable surfactants (foaming agents) are limited to non-ionic surfactants, including fatty alcohol sulphates, salts of sulphonated monoglycerides or fatty acids having from 10 to 20 carbon atoms, fatty acid-albumin condensation products, salts of fatty acids amides and taurines and/or salts of fatty acid esters of isethionic acid. In particular the amount of the non-ionic surfactant should not exceed from 15% by weight, more preferably 5% by weight, of the final dental care product.

Suitable neutralizing agents, used to maintain a pH in the range of 4.5 to 10, preferably in the range of 5.5 to 8 in the dental care product of the invention, include sodium bicarbonate, citrate, benzoate, carbonate, disodium hydrogen phosphate, or sodium dihydrogen phosphate.

Water is usually added to a dental care product in an amount giving e.g. a toothpaste in a flow-able form, i.e. an amount of from 40% to 70% by weight of the final product.

The dental care product of the invention may further include the addition of anti-calculus agents such as pyrophosphates and phosphonates; anti- plaque agents such as triclosan, chlorhexidine, bromochlorophene and sanquinarine; antibacterial proteins such as lanthibiotics (e.g. nisin); teeth de-sensitizing agents such as strontium salts and/or potassium nitrate or citrate; wound-healing agents such as allantoin, chlorophyll, tocopherol.

In addition, water-soluble anti-bacterial agents may also be included in the dental care product, such as chlorhexidine digluconate, hexetidine, alexidine, quaternary ammonium anti-bacterial compounds; and water- soluble sources of certain metal ions such as zinc, copper, silver and stannous ions (e.g. zinc, copper and stannous chloride, and silver nitrate). The presence of one or more fluoride ion-producing agent in the dental care product is particularly preferred as anti-caries agents. Suitable compounds yielding fluoride ions are inorganic fluoride salts, such as soluble alkali metal and alkaline earth metals salts, e.g. sodium fluoride, potassium fluoride, barium fluoride, calcium fluoride, ammonium fluoride, copper fluoride, zinc fluoride, sodium fluorosilicate, ammonium fluorosilicate, sodium fluorozirconate, sodium monofluorophosphate, aluminium mono- or di-fluorophosphate and fluorinated sodium calcium pyrophosphate.

The amount of fluoride ion-providing compounds in the dental care product is dependent upon the type of compound, its solubility, and the type of dental care product, but generally the amount lies from 0.005 to 3.0 wt.% in the final product, said amount releasing up to about 5,000 ppm fluoride ions by weight of the dental care product. Preferably the amount of fluoride ion-providing compound is sufficient to release about 300 to 2,000 ppm, more preferably 800 to 1 ,500 ppm of fluoride ions. These levels are typically achieved with alkali metal fluorides in an amount of up to 2 wt.%, more preferably between 0.05-1 wt.% in the dental care product; and in the case of sodium mono-fluorophosphate in an amount of 0.1-3 wt.%. In chewing gum dental care product the fluoride ion-providing compound is typically present in an amount sufficient to release about 500 ppm, preferably 25 to 300 ppm by weight of fluoride ions, corresponding to about 0.005 to 1.0 wt.% of such compound in the dental care product. Determination of fluoride levels in the oral hygiene product, as well as the resulting increase in salivary fluoride levels, can be determined with fluoride sensitive electrodes as described by Bruun et al. (1984).

In addition, the dental care product of the invention may contain zinc ions, generally in the form of a salt. Orally-acceptable anions with which zinc ions form a salt include: fluoride, fluorosilicate, monofluorophosphate, chloride, citrate, gluconate, thiocyanate, sulphate, acetate. The amount of zinc ions as Zn in a dental care product of the invention is in the range of 0.0025 - 0.15 wt.%, preferably from 0.01 to 0.1 wt.%, more preferably from 0.025 to 0.05 wt.%. The corresponding weight % of the zinc salt will be greater determined by the molecular weight of the anion in the salt.

The toothpaste may also contain various natural organic and inorganic ingredients from plants, herbs and salts that may have possible beneficial effects in the oral environment, mostly anti-bacterial. These may include herbs and herbal extracts such as Aloe Vera, various sorts of tea products including Green Tea, liquorice and extracts of liquorice, cocoa and extracts of cocoa, Iceland moss, and similar ingredients. In formulations low in fluoride the toothpaste may also contain various compounds with remineralising effects adding to the erosion protecting effect of the toothpaste. Such compounds may include amorphous calcium phosphate (ACP), casein phosphopeptide (CCP), arginine- bicarbonate/calcium-carbonate complexes (SensiStat®), bioactive glass (NovaMin®), and nano-hydroxyapatite. The remineralising content typically lies in the range from 0 to 10% by weight when the final dental product is toothpaste; preferably from 0 to 5% by weight.

In summary, a toothpaste produced from an dental care composition of the invention may e.g. comprise the following ingredients (in weight % of the final toothpaste composition):

10% to 70% abrasive material; 0 to 80% humectant; 0.1 % to 20% thickener; 0.01 % to 10% binder; 0.1 % to 5% sweetener; 0 to 15% foaming agent (non-ionic surfactant); 0.0001 % to 20% starch-degrading enzyme(s); 0 to 5% herbal extract(s) or other natural compounds with anti-bacterial effects, 0 to 1 % peroxide, and 0 to 5% remineralising compounds, wherein the product comprises less than 1 % ionic surfactant(s) (detergent) (preferably between 0 and 0.5%) and is substantially free of both (endo)protease(s) and lipase(s). The composition may be brought to 100% by the addition of water.

A mouthwash produced from an dental care composition of the invention may e.g. comprise the following ingredients (in weight % of the final mouthwash):

0 to 20% humectant; 0 to 2% non-ionic surfactant; 0.01 to 5% starch- degrading enzyme(s); 0 to 20% ethanol; 0 to 2% other ingredients (e.g. flavour, sweetener or other active ingredients such as fluorides); 0 to 70% water; 0 to 5% herbal extracts or other natural compounds with antibacterial effects; 0 to 5% of remineralising compounds, wherein the mouthwash comprises less than 1 % (more preferably between 0 and 0.5%) ionic surfactant(s) (detergent), and is substantially free of both (endo)protease(s) and lipase(s). The mouthwash may be buffered with an appropriate buffer, e.g. sodium citrate or phosphate in the pH-range 6-7.5, and may be brought to 100% by the addition of water.

The mouthwash may be in non-diluted form (i.e. to be diluted before use) or in diluted (ready-to-use) form.

The dental care compositions and products of the present invention can be made using methods, which are common in the oral product field.

The invention further relates to the use of one or more starch-hydrolysing enzymes as described above for the preparation of a composition for the prevention/inhibition of dental erosion.

A dental care product in solid to flow-able form such as toothpaste, when used for oral cavity treatment, will typically be contacted with the teeth and/or gums using a toothbrush or the like; while a chewing gum or lozenge will be brought in contact with teeth and/or gums by chewing. In the case of a liquid dental care product such as a mouthwash, the contact will typically take place by rinsing the mouth.

The time period during which a dental care product according to the invention is contacted with the teeth and/or gums to obtain the desired effect of preventing/inhibiting dental erosion can vary according to such factors as the nature of the composition or product and the need of the subject. However, contacting the dental care product with the teeth and/or gums for between about 30 seconds to 15 minutes will normally be sufficient for obtaining the desired result, e.g. contact by brushing the teeth or rinsing the mouth for a period of about 1 -3 minutes at a time. This is preferably performed on a regular basis, e.g. 1 -3 times a day. After use, the dental care product is typically removed from the mouth, e.g. by spitting it out, and the mouth may subsequently be rinsed with a liquid such as tap water.

Examples

Materials and methods: 1.1 Preparation of dental samples:

The source of tooth enamel for all experiments described below was from bovine incisors (obtained from mandibles of 36 months old cattle collected at a slaughterhouse). The teeth were extracted from the mandible using standard dental equipment and the teeth were cleaned free of organic debris with a toothbrush in tap water. Crowns were divided from their roots and sectioned in buccal and lingual blocks using a water-cooled saw. Between one and three buccal blocks, having a surface area with healthy enamel of one square millimetre (average weight 0.5-1.0 gram), were made from each tooth and then ground and wet-polished until plano- parallel using a water-cooled polishing machine with waterproof silicon carbide grinding paper (Struers, Ballerup, Denmark) having FEPA grit numbers of 500, 1000, 2400 and 4000 corresponding to particle sizes of 30.2, 18.3, 8.4 and 5.0 μm, respectively. Prior to the experiments surface microhardness (SMH) determinations were carried out at three locations on the surface of each enamel block. Only blocks of sound and healthy polished enamel having a surface microhardness between 320 and 350 kp/mm² were used for the experiments. After being approved for inclusion in the study the enamel blocks they were kept moist at all times, and stored in a fluid, which was saturated with respect to hydroxyapatite (0.4 mM aqueous calcium hydrogen phosphate solution adjusted to pH 6.0 or the clarified supernatant of Type I water exposed to hydroxyapatite crystals in excess for 1 month) in order to avoid demineralisation or re- mineralisation. Each enamel block was stored in a small amount of this fluid (<1 ml_) in a glass container at around 5⁰C to maintain a moist environment around the enamel until used. Although demineralisation of bovine enamel occurs slightly faster than demineralisation of human enamel, bovine tissue has comparable demineralisation and re- mineralisation characteristics (Featherstone and Mellburg, 1981 ). The advantage of bovine enamel is that it can be obtained in large quantities from animals that have lived under relatively similar conditions. Thus, permanent bovine incisors from cattle that are about 36 months old could be obtained from slaughterhouses for the experiments.

1.2 Measurement of microhardness:

Microhardness of the enamel surface of a tooth provides a quantitative measure of the hardness of the enamel surface, and changes in hardness are directly correlated with the process and amount of dental erosion. For all experiments described below the enamel surface microhardness (SMH) was determined with a Vickers microhardness tester. Here the area (A) of an indentation obtained in enamel after a diamond pyramid has been applied with a force (F) of 100 grams for 60 seconds was measured in a microscope and the SMH value calculated as: SMH=F/A, and expressed in kp/mm². If an enamel block is measure to have a surface microhardness of for instance 350 (kp/mm²) then a force of 350 kg is needed to make an indentation of one square millimetre in its surface.

1.3 Preparation of protein samples for coating enamel:

Human parotid saliva proteins were derived from human parotid saliva, which was collected directly, from both parotid glands simultaneously, from subjects by taste stimulation with a continuous flow of orange juice at the dorsum of the tongue (around 15 ml/min) to stimulate saliva production. Following collection, the saliva was dialysed with a membrane having a molecular weight cut off of 1 kDa to obtain a protein enriched fraction, which was lyophilised, and dissolved in Type I water at a concentration of 0.5% w/v. Human whole saliva proteins were derived from whole saliva obtained from more than 100 young and healthy subjects stimulated by paraffin chewing, and the protein fraction was dialysed in a similar manner as the parotid saliva, where the lyophilised protein fraction was dissolved in Type I water at a concentration of 0.5% w/v. Bovine colostrum protein was derived from raw milk obtained from cows within 12 hours of having calved. Excess fat was removed from the colostrum by ether extraction, whereafter the de-fatted colostrum was dialysed, lyophilised and dissolved in Type I water at a concentration of 0.5% w/v. Industrially-produced amylase preparations Aqueous solutions of BAN ® 480 L (bacterial α-amylase), Fungamyl ® 800L (fungal α-amylase derived from Aspergillus oryzae; US7,005,288B1 ), Liquozyme ® SC (thermostable α-amylase related to α-amylase derived from Bacillus stearothermophilus), and Termamyl ® 120 L [Type L] (α- amylase derived Bacillus licheniformis; WO90/11352), all kindly provided by the Novozymes Company (Novozymes A/S, Krogshoejvej 36, 2880 Bagsvaerd, Denmark) were used for the experiments. Each of the above protein preparations was dissolved (saliva proteins and colostrum) or diluted (industrially-produced amylases) in Type I water at a concentration of 0.5% w/v and used directly for coating enamel to form a pellicle in the following examples.

1.4 Method for simulating effect of acidic soft drinks on tooth enamel

For all experiments described below the effect of drinking acidic soft drinks on dental enamel was simulated by exposing the enamel surface to an excess amount of an eroding fluid for a period of four minutes at room temperature. The eroding fluid with a volume of 2 litres contained 2% tartaric acid buffered to pH of 2.3 with 5 mmol/L calcium hydrogen phosphate. This fluid is employed to simulate a highly acidic soft drink as for example Coca Cola. The addition of calcium hydrogen phosphate was to promote softening of the enamel rather than direct erosion (surface loss), where the latter is not measurable as changes in surface microhardness. After exposure to the eroding fluid, the enamel blocks were kept in HAp-saturated Type I water until SMH determinations were carried out at 3 locations on the surface of each enamel block within no more than 30 min.

1.5 Method for coating tooth enamel with protective layer of protein

For all experiments described below, which included testing the protective effects of proteins (salivary proteins, colostrum protein, one or more amylases), enamel blocks were placed in 10 ml_ test tubes and coated with 3 ml_ of Type I water containing 0.5% (w/v) of the proteins. The test tubes were mounted on a shaker so that the enamel was submersed in the protein solution for 15 seconds and then removed from the solution for another 15 seconds while within the test tubes. This setup was chosen, instead of simple immersion into the protein solutions, in order to simulate the cyclic flow of fluids in the oral cavity. Example 1. The effect of an anionic detergent on dental erosion

The experiment was performed to test the effect of exposure to sodium lauryl sulphate (SLS), at concentrations ranging between 1 and 5 percent (w/v) SLS, on the Surface MicroHardness [SMH] of dental enamel surfaces. Firstly, the SMH value of a sample of freshly polished enamel blocks was determined, and found to be 329 kp/mm² on average. The blocks were then immersed into 50 mL of Type I water containing from 1 and 5 percent (w/v) SLS for 30 minutes under constant stirring. After exposure to SLS the surface microhardness was determined once again and the new SMH values relative to the freshly polished enamel (ΔSMH%) were calculated as: ΔSMH% = SMH after SLS / SMH polished ^* 100. As shown in Figure 1 , a dose-dependent reduction in surface microhardness (SMH) values was detected after 30 minutes of exposure of freshly polished enamel to SLS. Accordingly, SLS dissolved in pure water may cause more demineralisation of enamel surfaces than pure water alone, most likely due to binding of free calcium ions in the crystal microenvironment.

Example 2. The effect of an anionic detergent on the protective capacity of salivary pellicles against acid-induced enamel softening of bovine enamel surfaces.

A sample of polished enamel surfaces, having a mean SMH value of 331 kp/mm², were produced as described above [section 1.2]. The sample was divided into four groups, and subjected to a pre-treatment of either: water only; coating with human whole saliva proteins alone; immersion in 3 ml of 2 percent (w/v) SLS in Type 1 water for 10 minutes followed by coating with human whole saliva proteins; or coating with human whole saliva proteins followed by immersion in 3 ml of 2 percent (w/v) SLS in Type 1 water. Coating with saliva proteins, comprising a 0.5% solution of human whole saliva proteins (w/v), for 30 minutes was performed as described above [section 1.5], which creates a protective layer of saliva proteins (or pellicle) on the surface of the enamel. The pre-treated samples were then immediately subjected to exposure to acid solution [2% tartaric acid buffered to pH of 2.3 with 5 mmol/L calcium hydrogen phosphate] for 4 minutes as described above [section 1.3].

The SMH of the treated enamel surfaces of each of the 4 samples was measured again, as described above. The mean SMH of the freshly polished enamel was 331 kp/mm², while the SMH of enamel pre-treated with water and then exposed to acid was 140 kp/mm², giving a loss of SMH for uncoated enamel of 193 kp/mm². The protective effect of the different pre-treaments on the enamel blocks following exposure to acid was calculated with respect to the loss in SMH measured for the enamel pretreated with water. Thus, a drop in SMH of 193 kp/mm² was set to equal 0% protection, whereas no drop in SMH was set to equal 100% protection. The protective effect of pellicles formed from coating with whole saliva proteins was 27±5% (Saliva only). As shown in Figure 2, the capacity of pellicles to protect bovine enamel against acid exposure was reduced when the enamel surface had been treated with a 2% SLS solution prior to pellicle formation with human salivary proteins as compared to untreated enamel surfaces having pellicles (p<0.05) giving rise to a reduced protective effect of 23±6%. It is thought, that binding of SLS to the hydroxyapatite hydration shells in the enamel causes a change in the surface net-charge towards neutral, and thereby alters the initial development of the pellicle causing less protein to be absorbed on the enamel, resulting in reduced protection against acid. Finally, Figure 2 shows that if enamel, coated with a pellicle of human salivary proteins, is subsequently exposed to SLS, this significantly reduces the protective effect of the pellicle towards acid treatment (p<0.01 ) giving rise to a further reduced protective effect of 21 ±5%. Accordingly, anionic detergents like SLS may interact negatively with the formation of the protective pellicle from salivary proteins on the enamel surfaces and reduce the protective effect of already formed pellicles.

Example 3. The effect of α-amylase levels in human parotid saliva on its protective capacity as a pellicle against acid-induced enamel softening of saliva-coated bovine enamel surfaces.

Saliva is a complex protein solution normally found in the oral cavity, which contains α-amylase. Healthy individuals were selected as a source of parotid saliva, which comprises a mixture of human parotid saliva proteins. Parotid saliva was collected directly, from both parotid glands simultaneously, from each of twenty subjects in total including thirteen males (23±1 yr) and seven females (22±1 yr) by taste stimulation with a continuous flow of orange juice at the dorsum of the tongue (around 15 ml/min) to produce as much saliva as possible. Following collection, the saliva was dialysed with a membrane having a molecular weight cut off of 1 kDa to obtain a protein enriched fraction, which was lyophilised, and dissolved in Type I water at fixed concentration of 0.5% w/v for all twenty samples. All other techniques including preparation of enamel blocks, determination of enamel surface microhardness, and determination of protective effects were performed as described in Example 2. After the protective effect (% protection) of each parotid saliva sample was determined, the total protein composition in the saliva from each of the twenty individuals was determined by high-performance liquid chromatography (HPLC). Low molecular weight proteins were separated using a BDS C18 HPLC column, after precipitation and removal of amylase and mucin with phosphoric acid, and detected at 214 and 280 nm. Higher molecular weight proteins, including amylase, were separated on a BioBasic AX column with gradient flow at pH 7.0 and determined at 280 nm. In total 25 different peaks, resembling salivary proteins, were identified in the three different chromatograms obtained by the HPLC analyses. By multiple regression analyses these peaks were related to the protective effect obtained from each parotid saliva sample. Surprisingly only the concentration of α-amylase determined by HPLC showed a significant positive correlation with the protective effects obtained. Figure 3 shows the relationship between the concentration of α-amylase in the saliva sample and the protective effect of pellicles developed during 30 minutes on bovine enamel from that same saliva (r=0.65; p<0.01 ). As shown, bovine enamel that was coated with parotid saliva having a high α- amylase concentration was able to maintain its surface microhardness better than enamel that was coated with saliva samples having a lower α- amylase concentration. Accordingly, α-amylase has the capacity to coat and protect enamel surfaces when present in a multicomponent system like saliva.

Example 4. A comparison of the protective capacity of pellicles formed from different amylase preparations against acid-induced enamel softening of bovine enamel surfaces

The industrially-produced amylases BAN, Fungamyl, Liquozyme, and Termamyl, were obtained from NOVOZYMES. The protective effect of these amylase preparations was compared with that of human whole saliva proteins, human parotid saliva proteins and bovine colostrum proteins. Human parotid saliva proteins were obtained and tested as described in Example 3 and human whole saliva proteins as described in Example 2. Bovine colostrum proteins were derived from raw milk obtained from cows within 12 hours of having calved. Excess fat was removed from the colostrum by ether extraction, where after the de-fatted colostrum was dialysed and lyophilised. All other techniques including preparation of enamel blocks, determination of enamel surface microhardness, and determination of protective effects were performed as described in example 2. Figure 4 shows the protective effect of human parotid saliva proteins, which is rich in α-amylase, human whole saliva proteins having a relatively lower α-amylase concentration than that of parotid saliva proteins, the industrially-produced α-amylase preparations, and bovine colostrum protein. The protection of enamel offered by industrial α-amylases was comparable to that of human whole saliva proteins at equal concentrations (0.5% w/v), which in one case was better than bovine colostrum, which has a protective effect against dental erosion. Although the 0.5% w/v solution of human parotid saliva proteins provided a better protection of enamel than industrially-produced α- amylases, the concentration of saliva proteins (0.5% w/v) used in the assay is far above that found in human parotid saliva, which under in vivo conditions is lower than 0.5% (around 2 mg/mL). Furthermore, the concentration of α-amylase that may be present in toothpaste can be as high as 5.0% w/v. Therefore, a toothpaste containing α-amylase can be manufactured to protect teeth against an acid exposure which is better than relying on human saliva.

Example 5. A comparison of the protective capacity of α-amylase in a dental composition substantially free of ionic detergents against acid-induced enamel softening of bovine enamel surfaces The effect of α-amylase in toothpaste was tested on a standard toothpaste, which was substantially free of anionic surfactant(s) (detergent), (endo)protease(s) and lipase(s), but comprising the non-ionic surfactant, Steareth-30. The fluoride concentration was 1100 ppm and the fluoride source was sodium fluoride. The α-amylase was the fungal derived α-amylase Fungamyl from Novo Nordisk, which was mixed with the toothpaste matrix to yield a concentration of 3.0% w/w in the toothpaste.

Positive control compositions: - Standard toothpaste comprising non-ionic surfactant, Steareth-30, and 1100 ppm of fluoride, but without α-amylase. Negative control composition:

Standard toothpaste with anionic detergent (SLS) and without α-amylase. The fluoride concentration was 1100 ppm and the fluoride source was sodium fluoride.

The following experiments that tested the effect of each of the three different toothpastes were designed to mimic a situation where teeth are exposed to a soft drink immediately following tooth brushing.

The sequence of experimental steps in the test comprised:

1. Microhardness measurement I 2. Coating with toothpaste slurry

3. Exposure to acid

4. Microhardness measurement Il

All analyses of microhardness were performed as described above [materials and methods 1.2]. Only tooth samples with enamel surfaces having a microhardness of between 320 and 350 kp/mm² (on average 335 kp/mm²) at measurement I, were selected for further analysis.

The selected enamel surfaces were exposed to a coating of toothpaste slurry for 30 minutes. The toothpaste slurry used for coating was introduced onto the enamel surfaces in a dilution of 1 :4 w/w in Millipore water at room temperature. This concentration was comparable to the toothpaste slurries used for coating enamel in similar studies (Fowler et al., 2006). The three toothpaste slurries were tested by immersing the enamel surfaces in 10 ml_ of each toothpaste slurry in a glass vial together with magnet rotating in a propeller fashion. After immersion in toothpaste, each enamel surface was exposed to 2 L of acidic eroding fluid [as given in Materials and methods: 1.4] for 5 minutes under constant and fast stirring. This time period is chosen as 3-5 minutes has previously been shown to be the time it takes for the oral fluids to regain supersaturation following intake of an acidic drink (Bashir and Lagerlόf, 1996).

Each series of experiments was repeated four times with 2 enamel surfaces exposed to each of the three toothpastes in each experiment. The microhardness (measurement II) of each enamel surface was then determined at three locations more than 0.1 mm apart. Microhardness values for the different toothpastes (8 enamel surfaces per toothpaste with three measurements on each) were expressed as mean ± standard deviation. Differences between the toothpastes were compared by a two- sample t-test. Figure 5 shows the surface microhardness of the toothpaste coated bovine enamel after it was exposed to the acidic solution. As shown, enamel that was exposed to the amylase containing toothpaste without ionic detergents was harder following the exposure to acid than enamel that was exposed to the toothpaste without amylase also without ionic detergents and with the same fluoride concentration (p<0.001 ). Enamel that was exposed to toothpaste containing ionic detergents (SLS) was softer than enamel exposed to toothpaste without ionic detergents with (p<0.001 ) and without (p<0.06) amylase. These differences were obtained in spite of the fact that all toothpastes had the same fluoride concentration of 1100 ppm. The experiment shows that it is possible to obtain a protective effect of industrially produced α-amylase also when it was embedded within a toothpaste matrix. Accordingly, none of the components normally found in toothpaste free of ionic detergents appear to reduce the protective effect of α-amylase against acid-induced enamel softening. Therefore it is realistic to use a regular toothpaste composition that is free of ionic detergents, as carrier for α-amylase in order to obtain increased protection against dental erosion and dental caries.

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Claims

1. Use of a starch-degrading enzyme of E. C. 3.2.1.1 for the manufacture of a dental care product for preventing and/or inhibiting dental erosion, wherein said product comprises less than 1 % ionic surfactant by weight.

2. Use according to claim 1 , wherein the dental care product is substantially free of endoprotease and/or lipase.

3. Use according to claim 1 or 2, wherein the starch-hydrolyzing enzyme is alpha-amylase of bacterial or fungal origin.

4. Use according to any one of the preceding claims, wherein the starch- hydrolyzing enzyme comprises from 0.1 % to 20% by weight of the dental care product.

5. Use according to any one of the preceding claims, wherein the dental care product further comprises one or more fluoride-ion releasing agent, wherein the agent is an inorganic fluoride salt selected from a soluble alkali metal and an alkaline earth metal salt.

6. Use according to claim 5, wherein the one or more fluoride-ion releasing agent is in an amount sufficient to release 300 to 2000 ppm of fluoride ions by weight of the dental care product.

7. Use according to any one of the preceding claims, wherein the dental care product further comprises a non-ionic surfactant in an amount not exceeding 15% by weight of the dental care product.

8. Use according to any one of the preceding claims, wherein the dental care product further comprises zinc ions in an amount in the range of 0.0025 - 0.15 % by weight of the dental care product.

9. Use according to any one of the preceding claims, wherein the dental care product is any one of a toothpaste, tooth gel, tooth powder, denture cleaning agent, mouthwash, lozenge or chewing gum.

10. Use according to any one of the preceding claims, wherein the dental care product is dental floss or a toothpick.

11. Use according to claim 9, wherein the dental care product further comprises one or more of an abrasive polishing material, whitening agent, flavoring agent, humectant, binder, thickener, and/or sweetener.

12. A dental care product for preventing and/or inhibiting dental erosion comprising a starch -degrading enzyme of E.C. 3.2.1.1 , wherein said product comprises less than 1 % ionic surfactant by weight.

13. A dental care product according to claim 12, wherein said product is substantially free of endoprotease and/or lipase.

14. A dental care product according to claim 12, wherein the starch- hydrolyzing enzyme is alpha-amylase of bacterial or fungal origin.

15. A dental care product according to any one of claims 12-14, wherein the starch-hydrolyzing enzyme comprises from 0.1 % to 20% by weight of the dental care product.

16. A dental care product according to any one of claims 12-15, wherein the dental care product further comprises one or more fluoride-ion releasing agent, wherein the agent is an inorganic fluoride salt selected from a soluble alkali metal and an alkaline earth metal salt.

17. A dental care product according to claim 16, wherein the one or more fluoride-ion releasing agent is in an amount sufficient to release 300 to

2000 ppm of fluoride ions by weight of the dental care product.

18. A dental care product according to any one of claims 12-17, wherein the dental care product further comprises a non-ionic surfactant in an amount not exceeding 15% by weight of the dental care product.

19. A dental care product according to any one of claims 12-18, wherein the dental care product further comprises zinc ions in an amount in the range of 0.0025 - 0.15 % by weight of the dental care product.

20. A dental care product according to any one of claims 12-19, wherein said product is any one of a toothpaste, tooth gel, tooth powder, denture cleaning agent mouthwash, lozenge or chewing gum.

21. A dental care product according to claim 11 , wherein said product is dental floss or a toothpick.

22. A method of preventing and/or inhibiting dental erosion in a mammalian subject, comprising the steps of: (a) contacting the dental care product of and one of claims 12-21 with the teeth and/or gums of the subject for between about 30 seconds to 15 minutes; wherein said contact is combined with brushing, chewing and/or rinsing.