GB2190288A

GB2190288A - Stabilized amine fluoride dental cream

Info

Publication number: GB2190288A
Application number: GB08711302A
Authority: GB
Inventors: Anthony John Morton; Ian William Stewart; Kenneth Harvey
Original assignee: Colgate Palmolive Co
Current assignee: Colgate Palmolive Co
Priority date: 1986-05-13
Filing date: 1987-05-13
Publication date: 1987-11-18
Anticipated expiration: 2007-05-13
Also published as: DE3715366A1; FR2598612A1; SE8701877D0; GB8711302D0; NL8701141A; CH674803A5; GB2190288B; SE8701877L; DK240887D0; FR2598612B1; ATA119287A; AT390190B; DK240887A

Description

GB2190288A 1

SPECIFICATION

Stabilized amine fluoride dental cream The present invention relates to a stabilized dental cream containing amine fluoride. In particular, 5 it relates to a dental cream containing amine fluoride which is stabilized against phase separation by the presence of low molecular weight polyethylene glycol.

Amine fluoride compounds have been proposed and used in dental creams and other types of oral compositions, such as mouthwashes, for their effect in promoting oral hygiene. For instance, they have the ability to increase resistance of dental enamel to acids, thereby improving the 10 ability of teeth to resist formation of cavities. They also can reduce formation of gingivitis and plaque in the oral cavity.

British Patents 865,272 and 1,021,058, each to Gaba A.G. describe oral compositions includ ing toothpastes and dental creams which contain amine fluoride compounds. In particular, in British Patent 1,021,058, amine fluoride dental cream compositions are specifically exemplified 15 wherein insoluble sodium metaphosphate is used as polishing agent, sorbitol is present as humectant and gelling agent, including methyl cellulose is also present. The patent also discusses glycerol (that is, glycerine) as an alternative humectant.

U.S. Patent 3,914,406 to Yankell also describes amine fluoride oral compositions including toothpastes and includes an example wherein insoluble sodium metaphosphate polishing agent, 20 sorbitol humectant and hydroxyethyl cellulose gelling agent are employed. The patent also discloses as humectants, -sorbitol, glycerine, polyhydric alcohols of like nature or mixtures thereof-. However, in the specific examples the only mixtures (sorbitol solution and glycerine) are used in mouthwashes, while the toothpastes contain either sorbitol solution or propylene glycol. 25 It has been observed that dental creams such as are generally characteristic of the prior art undergo phase separation when the polishing agent has a substantial content of insoluble alkali metal metaphosphate, the humectant is sorbitol or glycerine and the gelling agent is non-polar cellulosic material. Use of alternative polyhydric alcohol of like nature as the sole or main humectant, for instance in amounts of about 15% or more, has not been satisfactory. For 30 instance, when an amine fluoride dental cream containing 20% of polyethylene glycol of average molecular weight of about 600 is employed, an undesirable flavour note is provided.

It is an advantage of the present invention that separation in amine fluoride dental cream of a liquid phase from the solid or gelled portion of the dental cream is reduced or overcome.

In accordance with certain of its aspects the present invention relates to a dental cream 35 comprising a material which provides to the said dental cream about 0.01- 1% by weight of soluble fluoride, at least about 70% by weight of the said material being an amine fluoride, about 25-80% of an aqueous liquid phase comprising humectant in amount of at least about 20% by weight of the said dental cream, the said humectant being selected from the group consisting of sorbitol, glycerine and mixtures thereof, a solid phase comprising about 0.2-5% by 40 weight of a nonionic cellulosic gelling agent and about 20-75% by weight of a polishing material containing insoluble alkali metal metaphos-phate as at least the major components of the said polishing material, wherein the said dental cream is stabilised against phase separation by incorporation into the said aqueous humectant phase of polyethylene glycol having an average molecular weight of about 200-1000, wherein the weight ratio of the said humectant to the 45 said polyethylene glycol is from about 10:1 to about 12, the amount of polyethylene glycol being at least about 2% by weight.

The term amine fluoride as used herein, includes amine hydrofluorides as well as quaternary ammonium fluorides. These are employed in amounts which provide about 0. 01-1% by weight of soluble fluoride to the dental cream, preferably about 0.05-0.15%. 50 Typically, they are characterised as having the formula:

55.55 F W R 60 Wherein R represents an alkyl, alkenyl, alkylol, alkoxyalkyl, aryl, aryloxyalkyl, aralky], cycloalkyl, cycloalkenyl or heterocyclic group or an additional quaternary ammonium group which may be attached to the nitrogen atom by a bridging group or a group of the formula -R-CO.Y wherein Y represents an OH, alkoxy, cycloalkoxy, or aralkoxy group or 65 2 GB2190288A 2 R2 -N 5 R3 where R' represents an alkylene or arylene-alkylene and each of R 2 and R3 represent a hydrogen atom or an alkyl, alkenyi, alkylol, aryl, aralkyl, cycloalkyl or heterocyclic radical, or R2 and R3 form together with the nitrogen atom a heterocyclic nucleus, each one of the three free valences 10 being satisfied by an alkyl, alkenyl, alkylol, alkoxyalkyl, aryl, aryloxyalkyl, aralkyl, cycloalkyl, or heterocyclic group or at least two of the free valences being satisfied by a group forming together with the nitrogen atom, a saturated or unsaturated, unsubstituted or substituted heterocyclic nucleus. 15 The following compounds are specific examples of amine fluorides which may be employed in 15 accordance with the present invention. The invention is not intended to be limited to these compounds. Octyl-trimethyl-ammonium fluoride, dodecyi-ethyi-dimethyi-ammonium fluoride, tetraethyl ammonium fluoride, dilauryl-dimethyl-ammonium fluoride, 8,9 octadecenyi-benzyi-dimethyi-ammon- ium fluoride, furfuryi-iauryi-dimethyi-ammonium fluoride, phenoxyethyicetyl-dimethyi-ammon- 20 ium fluoride, N,N1-tetra-methyl-N,NI-dilauryi-ethylene-diammonium difluoride, N-cetyl-pyridi nium fluoride, N,N-dilauryl-morpholinium fluoride, N-myristyl-N-ethyl- morpholinium fluoride, N-(oetylamino-carbonylethyl)-N-benzyi-dimethyi-ammonium fluoride, N-(2 ethoxy-ethyi)-N-do decyl-dimethyl-ammonium fluoride, N-(o,-hydroxy-dodecyi)-trimethyi- ammonium fluoride, N-(2-carbomethoxy-ethyi)-N-benzyi-dimethyi-ammonium fluoride, N-(2-carbocyclo-hexoxy- 25 ethyi)-N myristyl-dimethyi-ammonium fluoride, N-(2-carbobenzyioxyethyi)-N- dodecyi-dimethyi- ammonium fluoride, N-(2-(NI, NI-dimethylamino-carbonyi)-ethyi-N-dodecyi- dimethyi-ammon- ium fluoride, and N-carboxy-methyi-N-eicosyi-dimethyi-ammonium fluoride.

The amine fluorides of the present invention are soluble in water, and most of them are also soluble in methanol and ethanol. There are mostly hygroscopic crystalline solids or syrups. 30 Those of the quaternary ammonium fluorides which have long-chain substituents dissolve in water with formation of foaming solutions.

Additional amine fluoride compounds which may be used in the present invention, and indeed are preferred, are amine hydrofluorides having the formula:

35 RXHF Wherein R represents an alkyl or alkenyl group having from about 10 to about 24 carbon atoms, advantageously from 14 to 21 carbon atoms; 40 R2 X represents - NH2 or -N- (CH2)y N 1 3 45 1 1 R R in which y is an integer of from 1 to 3, and R', R2 and R3 each represent a hydrogen atom; a 50 lower alkyl, lower alkenyl or lower alkanol group having up to 5 carbon atoms.

Exemplary of compositions of the present invention are those which comprise the hydrofluo ride salts of decylamine, dodecylamine, dodecenylamine, tetradecylamine, tetradecenylamine, pen tadecylamine, hexadecylamine, hexadecenylamine, octadecylamine, octadecenylamine, eicosylam ine, tetracosylamine, and N-(Bis-(hydroxyethyi)-aminopropyi)-N(hydroxyethyi) alkylamine 55 wherein the alkylamine is a mixture of alkylamine groups containing from about 12 to about 18 carbon atoms.

Advantageous compositions of the present invention are those which comprise 9-icta decbtwhich comprise 9-octadecnylarnine hydrofluoride, hexadecylamine hydrofluoride, N-(Bis-ffly droxyethyi)-aminopropyi)-N(hydroxyethyi)octadecylamine dihydrofluoride, or N,N,N-Tris-(2-hy- 60 droxyethyl 1)-N-octadecyi-l, 3-diamino-propane dihydrofluoride.

Further, a mixture of N-(Bis-(hydroxyethyi)-amino-propyi)-N(hydroxyethyi) octadecylamine dihydrofluoride and hexadecylamine hydrofluoride is also desirable.

In accordance with preferred aspects of the present invention, the entire soluble fluoride providing material is the amine fluoride. Also included are compositions in which up to 30% by 65 3 GB2190288A 3 weight of the soluble fluoride providing material may be an additional non-toxic, water-soluble fluoride-providing compound or mixture thereof. Among these additional compounds (including mixtures thereof) are inorganic salts which provide fluoride, such as suitable alkali metal, alkaline earth metal, and heavy metal salts, for example, sodium fluoride, potassium fluoride, ammonium fluoride, a copper fluoride, such as cuprous fluoride, zinc fluoride, a tin fluoride such as stannous 5 fluoride or stannous chlorofluoride, sodium fluorosilicate, ammonium fluorosilicate, sodium fluoro silicate, sodium fluorosilicate, ammonium fluorosilicate, sodium fluorozirconate, sodium monofluo rophosphate, aluminium mono and difluorophosphate, and fluorinated sodium calcium pyrophos phate. When present, alkali metal salts such as sodium fluoride and sodium monofluorophos- phate are preferred. 10 In dental cream formulations the liquids and solids are proportioned to form a creamy mass of desired consistency which is extrudable from a collapsible tube (for example, lacquered aluminum, wax-lined lead or laminated plastic) or a mechanically operated or pressure differential dispenser. The liquid phase comprises about 25-80% by weight of the dental cream and includes water together with at least one of sorbitol and glycerine as humectant, the amount of 15 sorbitol and/or glycerine being at least about 20% by weight of the dental cream, preferably about 20-40%. Sorbitol is the preferred humectant and is typically employed as a 70% aqueous solution. Water is present, typically in amount of at least about 5% by weight, preferably about 15-40%.

The gelling agent for use in the dental cream formulations of the present invention is a 20 nonionic cellulosic gelling agent, such as methyl cellulose, hydroxymethyl cellulose, ethyl cellu lose, hydroxyethyl cellulose, propyl cellulose, hydroxypropyl cellulose and the like. Hydroxyethyl cellulose is preferred. The gelling agent is present in an amount of about 0.2-5% by weight of the dental cream, preferably about 0.13-2.0%.

Grades of hydroxyethyl cellulose which may be used include those given in Table 1 below: 25 TABLE 1

SUPPLIER HEC GRADE VISCOSITY (CPS) Hercules Natrosol 250M and MR 4500 6500 30 Natrosol 250 HR 1500 - 2500 and 250 H Natrosol 250 HHR 3400 - 5000 35 and 250 HH B.P. Chemicals Cellobond 5000 A 4200 - 5600 11 Cellobond 7000 A 6000 - 7000 40 Hoechst Tylose H 4000 P 3000 - 5000 Tylose H 10000 P 7000 - 12000 Notes on Table 1 45 1% solution (Brookfield; 25oC)

Hoeppler Viscometer (2%; 20OC) Natrosol 250 M is preferred. 50 The polishing material employed in the dental cream formulations is present in amounts of about 20-75% by weight, preferably about 35-65%. Most preferably it is all or substantially all insoluble alkali metal metaphosphate. It is within the scope of the present invention that insol55 uble alkali metal metaphosphate may be present as the major polishing agent (at least 50.0%) in admixutre with a minor amount of secondary polishing agent, such as calcined alumina, decal cium phosphate (anhydrous or dihydrate), calcium pyrophosphate, tricaicium phosphate, calcium carbonate, trimagnesium phosphate trihydrate and magnesium carbonate. When secondary pol ishing agent is present, it is preferred that it be in amount of up to about one-third the amount 60 of insoluble alkali metal metaphosphate, with the weight ratio of insoluble alkali metal metaphos phate to secondary polishing agent being about 3:1 to about 99A, preferably about 8:1 to about 12: 1.

Insoluble sodium metaphosphate is the preferred salt of the waterinsoluble alkali metal polym etaphosphates. It is known, for example, as Maddrell or Kurrol salt. Water-soluble polymetaphos- 65 4 GB2190288A 4 phates such as di-, tri-, tetra-, or hexa-metaphosphate are not intended to be covered by the invention. These latter may, however, be present as impurities in the water-insoluble polymetaphosphates which can be used in accordance with the invention. The commercially available water-insoluble sodium polymetaphosphate may for example, contain up to 4% of a watersoluble metaphosphate. 5 Low molecular weight polyethylene glycol of average molecular weight of about 200-1000, preferably about 400-1000, disperses readily in the liquid vehicle and is effective to prevent the dental cream from undergoing phase separation or syneresis. In order to effect dispersion readily, grades of polyethylene glycol which are normally solid at room temperature are heated to liquify them. Low molecular weight polyethylene glycol is employed in amount such that the 10 weight ratio of humectant (glycerine and/or sorbitol) to polyethylene glycol is from about 10:1 to about 1:2, preferably from about 2:1 to about 1A. the polyethylene glycol is present in amount of at least about 2%, by weight, typically about 2-10% and preferably about 4-10%. Organic surface-active agents may be used in the dental cream of the present invention to achieve increased prophylactic action, assist in achieving thorough and complete dispersion of the com- 15 positions of the present invention throughout the oral cavity, and render the dental creams more cosmetically acceptable. The organic surface-active material is typically non-ionic, ampholytic or cationic in nature, and it is preferred to employ as the surface-active agent a detersive material which imparts to the composition detersive properties.

Suitable surface-active materials include nonionic agents such as condensates of sorbitan 20 monostearate with approximately 20 moles of ethylene oxide, condensates of ethylene oxide with propylene glycol (---Pluronic- materials) and amphoteric agents such as long chain (alkyl) amino-alkylene alkylated amine derivatives, which are available under the trademark---Miranol such as Miranol C2M. Cationic surface-active germicides and antibacterial compounds such as di-isobutyl phenoxy ethoxy ethyl dimethyl benzyi ammonium chloride, benzyi dimethyl steary] 25 ammonium chloride, benzyl dimethyl stearyl ammonium chloride, tertiary amines having one fatty alkyl group (of from 12-18 carbon atoms) and two (poly) oxyethylene groups attached to the nitrogen (typically containing a total of from about 2 to 50 ethanoxy groups per molecule) and salts thereof with acids, and compounds of the structure 30 (CH2 CH 2 0) Z H (CH2CH20) X H 11 i-CH2CH2CH2-N-(CH2CH20) Y H 35 where R represents a fatty alkyl group containing from about 12 to 18 carbon atoms, and x, y and z total 3 or higher, as well as salts thereof with mineral or organic acids, may also be used. 40 It is preferred to use about 0.05-5% by weight of surface-active material.

Any suitable flavouring or sweetening materials may be employed in formulating a flavour for the composition of the present invention. Examples of suitable flavouring constituents include the flavouring oils, e.g. oils of spearmint, peppermint, wintergreen, sassafras, clove, sage, eucalyp tus, marjoram, cinnamon, lemon and orange, as well as methyl salicylate. Suitable sweetening 45 agents include sucrose, lactose, maltose, xylitol, sodium 6-methyl-3, 4- dihydro-1, 2, 3-oxathi azine-4-one, sodium cyclamate, perillartine, sodium saccharin and saccharin acid. Suitably, flavour and sweetening agents may together comprise from about 0.01 to 5% or more of the compositions of the present invention.

Various other materials may be incorporated in the dental cream. Examples thereof are colour- 50 ing or whitening agents or dyestuffs, preservatives, anti-corrosive agents, silicones, chlorophylic compounds, additional ammoniated materials such as urea, diammonium phosphate and mixtures thereof and other constituents. Whitening agents, such as titanium dioxide, typically in amounts of about 0.05-2%, may be beneficial to the appearance of the dental composition, since upon aging, some discolouration may occur. 55 The adjuvants are incorporated in the compositions of the present invention in amounts which do not substantially adversely affect the properties and characteristics desired and are selected and used in proper amounts depending upon the particular type of compositions involved.

Antibacterial agents may also be employed in the oral compositions of the present invention in an amount of about 0.01-5% by weight. 60 When an insoluble alkaline earth metal salt is present as the secondary polishing agent, there is typically employed various calcium and magnesium ion suppression agents for adjustment of physical properties of the compositions. Suitable agents are the water- soluble inorganic poly phosphate salts, such as tetrasodium pyrophosphate or disodium diacid pyrophosphate, with the partially neutralized or acid polyphosphate preferred. Other suitable agents are the alkali metal, 65 GB2190288A 5 preferably sodium, salts of citric acid. In general, such compounds will be a minor amount or proportion of the formulation. The precise amount will vary depending upon the specific formula tion, such as the physical characteristics of the dental cream, but will usually be from a-bout 0 1 % to about 3% by weight.

The dental creams should have a pH practicable for use. A pH range of about 3.5 to 9 is 5 particularly desirable. The reference to the pH is meant to be the pH determination directly on the dental cream. If desired, materials such as citric acid may be added to adjust the pH to say preferably about 4-8.

The invention may be put into practice in various ways and a number of specific embodiments will be described by way of example to illustrate the invention with reference to the accompany- 10 ing examples. All amounts and proportions are by weight except as otherwise indicated.

EXAMPLES 1A and 18 The following dental creams having the ingredients and proportions set out in Table 2 are prepared: 15 TABLE 2

Examples 1A 1B Ingredients 20 Glycerine 23.0 13.0 Polyethylene Glycol 600 - 10.0 Hydroxyethyl Cellulose (Natrosol 1.5 1.5 25 25OM) Sodium Saccharin 0.4 0.4 Water (Deionised) 27.1 27.1 30 Titanium Dioxide 0.5 0.5 Amine Fluoridel 33% 4.0 4.0 Insoluble Sodium Metaphosphate 42.0 42.0 35 Polyoxyethylene Sorbitan - 0.5 0.5 Ethylene Oxide (20:1) Monostearate 40 Flavour 1.1 1.1 Note on Table 2 45 1 The Amine Fluoride is N,N,N-tris (2-hydroxyethyi)-N-octadecyi-l, 3- diaminopropane dihy drofluoride.

In preparing the above dental cream polyethylene glycol 600 is dispersed with glycerine prior to addition of hydroxyethyl cellulose to form a product of creamy consistency.

After aging for 12 weeks at 43'C the dental cream of Example 113 remains substantially 50 rheologically stable while substantial syneresis of the dental cream of Example 1A is observed within 4 weeks.

EXAMPLES 2A and 28 Dental creams are prepared corresponding to the dental creams of Examples 1A and 113 55 respectively, except that sorbitol (70%) replaces glycerine.

After aging for 12 weeks at 43'C only very slight phase separation is observed with the dental cream of Example 213 while substantial syneresis of the dental cream of Example 2A is observed within 2 weeks.

60 EXAMPLES 3A to 3E The amounts of glycerine and polyethylene glycol 600 in the dental cream of Example 113 are varied as given in Table 3 below:

6 GB2190288A 6 TABLE 3

Glycerine Polyethylene Glycol 600 Example Parts Parts 3A 20.0 2.0 5 313 19.0 3.0 3C 18.0 4.0 3D 16.0 6.0 3E 14.0 8.0 10 After aging for 3 weeks at 49'C, only very slight phase separation is observed with the dental cream of Example 3A, only very slight phase separation with the dental creams of Examples 313 and 3C after 9 weeks at 49'C and substantially no phase separation is observed with the dental creams of Examples 3D and 3E even after aging for 9 weeks at 49'C.

15 EXAMPLES 4A to 4D Polyethylene glycol of average molecular weights indicated below is used to replace polyethylene glycol 600 in the dental cream of Example 113 with the amounts of glycerine and polyethylene glycol also varied as indicated in Table 4 below:

20 TABLE 4

Polyethylene Glycol Glycerine Average Example Parts Mol. wt. Parts 4A 18.000 400 4.000 25 413 16.000 400 6.000 4C 18.000 1000 4.000 41) 16.000 1000 6.000 After aging for 9 weeks at 49'C there is substantially no phase separation with the dental 30 creams of Examples 4A and 4C, only very very slight phase separation with the dental cream of example 413 and only very slight phase separation with the dental cream of Example 4C. In the dental creams of Examples 4A and 4D glycerine is heated to WC prior to dispersion of polyethylene glycol 1000 therein.

35 EXAMPLES 5A to 5C The amounts of sorbitol (70%) and polyethylene glycol 600 in the dental cream of Example 213 is varied as given in Table 5 below:

TABLE 5 40

Sorbitol (70 %) Polyethylene Glycol 600 Examples Parts Parts 5A 18.000 4.000 513 17.000 5.000 5C 16.000 6.000 45 After aging for 9 weeks at 4WC there is substantially no phase separation with the dental creams of Examples 5A and 5C and only an indication of very slight phase separation with the dental cream of Example 5B.

50 EXAMPLE 6

A dental cream which does not separate into phases upon aging is prepared by varying the dental cream of Example 213 to reduce the amount of insoluble sodium metaphosphate to 37.8 parts and including 4.2 parts of calcined alumina.

55 EXAMPLES 7A and 7B The following dental creams having the ingredients and proportins given in Table 6 do not separate into phases upon aging.

7 GB2190288A 7 TABLE 6

Examples 7A 7B Ingredients Parts 5 Glycerine 16.000 16.000 Polyethylene Glycol 600 6.000 6.000 Hydroxyethyl cellulose (Natrosol 1.500 1.500 10 250M) Sodium Saccharin 0.400 0.400 Water (Deionised) 29.133 29.053 15 Titanium Dioxide 0.500 0.500 Amine Fluoride' (33%) 2.800 2.800 Sodium Monofluorophosphate - 0.114 20 Sodium Fluoride 0.067 0.033 Insoluble Sodium Metaphosphate 42.000 42.000 Polyoxyethylene Sorbitan- 0.500 0.500 25 Ethylene Oxide (20:1) Monostearate Flavour 1.1 1.1 30 Note on Table 6 35 1 The Amine Fluoride is N,N,N-tris (2-hydroxyethyi)-N-octadecyi-l, 3diaminopropane dihy drofluoride.

In the foregoing examples, the 4.0 parts of the 33% solution of the Amine Fluoride may be replaced by 4.344 parts of a 1:4 mixture of N-(Bis-(hydroxyethyi)- aminopropyi)-N-(hydroxye- 40 thyl) octadecylamine dihydrofluoride and hexadecylamine hydrofluoride, with similar results.

In the foregoing examples, sodium cyclamate may replace sodium saccharine.

It is apparent that the above examples illustrate the invention and various modifications may be made thereto.

45

Claims

1. A dental cream comprising a material which provides to the said dental cream about 0.01-1% by weight of soluble fluoride, at least about 70% by weight of the said material being an amine fluoride, about 25-80% of an aqueous liquid phase comprising humectant in amount of at least about 20% by weight of the said dental cream, the said humectant being selected from 50 the group consisting of sorbitol, glycerine and mixture thereof, a solid phase comprising about 0.2-5% by weight of a nonionic cellulosic gelling agent and about 20-75% by weight of a polishing material containing insoluble alkali metal metaphosphate as at least the major compo nents of the said polishing material, wherein the said dental cream is stabilised against phase separation by incorporation into the said aqueous humectant phase of polyethylene glycol having 55 an average molecular weight of about 200-1000, wherein the weight ratio of the said humec tant to the said polyethylene glycol is from about 10:1 to about 1:2, the amount of polyethylene glycol being at least about 2% by weight.

2. A dental cream as claimed in Claim 1 in which the said amine fluoride is present in an amount which provides about 0.05-0.15% by weight of soluble fluoride. 60

3. A dental cream as claimed in Claim 1 or Claim 2 in which the said amine fluoride is N,N,N-tris (2-hydroxyethyi)-N-octadecyi-l, 3-diaminopropane dihydrofluoride.

4. A dental cream as claimed in Claim 1, 2 or 3 in which the said nonionic cellulosic gelling agent is present in an amount of about 0.8-2% by weight.

5. A dental cream as claimed in any one of Claims 1 to 4 in which the said nonionic 65 8 GB2190288A 8 cellulosic gelling agent is hydroxyethyl cellulose.

6. A dental cream as claimed in anyone of claims 1 to 5 in which the said polishing agent is present in an amount of about 35-65% by weight.

7. A dental cream as claimed in any one of Claims 1 to 6 in which the said insoluble alkali metal metaphosphate is insoluble sodium metaphosphate. 5

8. A dental cream as claimed in Claim 7 in which the said insoluble sodium metaphosphate is the sole polishing material present.

9. A dental cream as claimed in any one of Claims 1 to 8 in which the said polyethylene glycol is present in an amount of about 2-10% by weight.

10. A dental cream as claimed in Claim 9 in which the said polyethylene glycol is present in 10 an amount of about 4-10%.

11. A dental cream as claimed in any one of Claims 1 to 10 in which the said polyethylene glycol has an average molecular weight of about 400-1000.

12. A dental cream as claimed in Claim 11 in which the said polyethylene glycol has an average molecular weight of about 600. 15

13. A dental cream as claimed in any one of Claims 1 to 12 in which the said amine fluoride is the sole fluoride providing material present.

14. A dental cream as claimed in any one of Claims 1 to 13 in which up to about 30% of the fluoride providing material is inorganic fluoride providing salt.

15. A dental cream as claimed in Claim 14 in which the said inorganic fluoride providing salt 20 is selected from the group consisting of sodium fluoride, sodium monofluorophosphate and mixture thereof.

16. A dental cream as claimed in Claim 1 substantially as specifically described herein with reference to any one of Examples 1 B, 213, 3A to 3E, 4A to 4D, 5A to 5C, 6 or 7A or 7B.

Printed for Her Majesty's Stationery Office by Burgess & Son (Abingdon) Ltd, Dd 8991685, 1987.

Published at The Patent Office, 25 Southampton Buildings, London, WC2A 1 AY, from which copies may be obtained.

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