Dental Care

Preparation used in dental care

Dental Care Abstract
A preparation used in dental care to protect the teeth, which preparation is anhydrous, with the possible exception of crystal water, and by structure, for example a powder, solid tablet or other anhydrous compositions. The preparation contains a remineralising component. pH buffer component, xylitol and fluoride. Due to the effect of the water contained in the saliva or water added otherwise, the compounds in the preparation react with each other so as to bring about both a remineralisation reaction correcting cavity formation in the teeth, and a pH buffering reaction prevention cavity formation in the teeth.

Dental Care Claims
We claim:

1. An anhydrous preparation used in dental care, consisting essentially of:

a) an organic or inorganic calcium compound having buffering capacity,

b) an alkali metal phosphate,

c) an alkali metal fluoride, and

d) xylitol

in amounts such that, due to the effect of water contained in saliva or water added otherwise, said components (a), (b) and (c) in the preparation react with each other so as to bring about a remineralisation reaction correcting cavity formation in teeth and an alkaline pH buffering reaction preventing cavity formation in teeth, and that said prepreparation causes an effect of stimulating salivary secretion.

2. A preparation as claimed in claim 1, wherein the preparation is in a compressed form selected from the group consisting of a tablet, capsule, lozenge and chewing gum.

3. A preparation as claimed in claim 1, wherein, due to the effect of water or saliva, said preparation forms a remineralising ingredient containing at least one phosphate and/or fluoride compound, which is present as an alkali metal salt.

4. A preparation as claimed in claim 1, wherein the remineralising ingredient is hydroxyapatite and/or fluoride apatite.

5. A preparation as claimed in claim 1, wherein the remineralising ingredient is an alkali metal fluoride.

6. A preparation as claimed in claim 1, wherein said alkali metal phosphate and said alkali metal fluoride are contained in said preparation as the compound sodium monofluorophosphate.

7. A preparation as claimed in claim 1, wherein said calcium compound is a carbonate or organic calcium salt.

8. A preparation as claimed in claim 1, wherein said inorganic or organic calcium compound having buffering capacity is a carbonate, hydrogen carbonate, acetate, propionate, sorbate, ascorbate, aspartate, lysinate, gluconate, or lactate.

9. A preparation as claimed in claim 1, wherein said alkali metal phosphate is selected from the group consisting of phosphate, pyrophosphate, polyphosphate, and hydrogen phosphate.

10. A preparation as claimed in any of the claim 1, wherein the preparation is a dry tablet which disintegrates on coming into contact with saliva.

11. A preparation as claimed in claim 1, wherein the preparation is a tablet containing the following ingredients: xylitol, calcium carbonate, disodium hydrogen phosphate, zinc ascorbate, sodium fluoride, magnesium stearate, silicon dioxide (Aerosil) and menthol.

12. A preparation as claimed in claim 1, wherein the preparation is a tablet containing the following ingredients: xylitol, calcium acetate, dipotassium hydrogen phosphate, zinc oxide, potassium fluoride and liquorice root powder.

13. A preparation as claimed in claim 1, wherein the preparation is a tablet containing the following ingredients: xylitol, calcium carbonate, calcium acetate, calcium ascorbate, disodium hydrogen phosphate and sodium fluoride.

14. A preparation as claimed in claim 1, wherein the preparation contains more than 0.1% of calcium in order to bring about remineralisation.

15. A preparation as claimed in claim 5, wherein said alkali metal fluoride is selected from sodium fluoride, potassium fluoride and mixtures thereof.

16. A preparation as claimed in claim 15, wherein the preparation contains more than 1% of calcium.

Dental Care Description
The object of the invention is a preparation used in dental care.

Problems relating to teeth are caused by cavity formation, or caries, and chemical dissolution caused by acids, or erosion. These continue to be a major health problem also among adults. Due to various factors, caries in particular is increasingly a problem for the ageing adult population who still have their own teeth. Such factors include impaired motor coordination, lack of motivation, reduced salivary secretion, use of medication or general ill health.

In simple terms, caries and erosion represent a change in the equilibrium state between demineralisation and remineralisation, towards demineralisation. The oral remineralising capacity is maintained by the saliva, particularly the calcium and phosphate contained in the saliva and the buffering capacity of the saliva.

According to present knowledge, the importance of fluoride used in dental care lies in the stimulation of remineralisation. Remineralisation occurs in the mouth daily, for example, always after a meal, due to the effect of the saliva. Even small repeated fluoride concentrations in the mouth are advantageous, because in the presence of fluoride, the apatite crystals apposited on the hard tissue of the tooth are more resistent to acids and more regular in structure than those formed without fluoride.

Xylitol, another substance used in dental care, has many good properties. Firstly, it does not form organic acids harmful to the teeth through the action of bacteria. Being a sweet substance, it stimulates salivary secretion, which means that the calcium, phosphate and bicarbonate concentrations in the saliva increase. Xylitol also reduces the amount of the most detrimental caries bacteria, such as the so-called mutans streptococci, on the surface of the teeth. Calcium and phosphate are essential ingredients of the saliva, as saliva contains useful calcium and phosphate salts in soluble, supersaturated form. They may either be precipitated onto the surface of the teeth during remineralisation or they may form calculus above the gums.

A useful and important property of saliva is its buffering ability, or buffer capacity. A high and good buffer capacity prevents the detrimental demineralisation effects caused to the hard issue of the dentition by both caries arising from acids produced by bacteria, and by erosion caused, for example, by the acids in food. The buffer capacity of saliva follows primarily from its bicarbonate content.

In patients with reduced salivary secretion, the natural defence mechanisms of the saliva have deteriorated, including its remineralising capacity. These patients are particularly prone to all hard tissue damage to the dentition, particularly to caries. For this reason, for example, rinsing with fluoride and so-called remineralisation solutions have already for many years been recommended to hyposalivation patients, in order to increase the resistance of the teeth. The use of xylitol has also been recommended. The problem is that all these preparations are separate. No easy-to-use and effective preparation is known which contains even most of the agents favourable to the health of the dentition.

Attempts have, however, been made to combine several of the above-mentioned agents into one preparation. One such preparation is a lozenge presented by the researchers Nilner, Vassilakos and Birkhed (Nilner K, Vassilakos N, Birkhed D. Effect of buffering sugar-free lozenge on intraoral pH and electrochemical action. Acta Odontol Scand. 1991:49: 267-272). The preparation contains 43.8% of xylitol and 42.3% of sorbitol. In total, the proportion of these sugar alcohols, which are present in a ratio of approximately 1:1 is thus 86.1%. The buffering compounds in this preparation are sodium bicarbonate (3.0%), sodium hydrogen phosphate (3.2%), disodium hydrogen phosphate (3.3%), and sodium: polyphosphate (1.2%). The proportion of these sodium salt buffers in the total weight of the preparation is thus 10.6%.

This formulation also contains 0.77% of carboxymethylcellulose as a binder, and the usual amount, that is, 1.38% of magnesium stearate, known as an additive in tabletting. The formulation also contains 0.92% of mint aroma as flavouring and small amounts of non-buffering salts, such as 0.17% of calcium chloride and 0.015% of zinc chloride. The researchers explain that the buffering effect of the formulation is based on the bicarbonate phosphate buffer.

The above-mentioned formulation has been shown to clearly increase the salivary buffer capacity. The greatest disadvantage of the preparation is, however, the complete lack of fluoride. Correspondingly, the proportion of calcium is also extremely small, because 0.17% of salt contains only 0.061% of calcium. In other words, one 650 mg lozenge contains only 0.40 mg of calcium.

Due to the above, this formulation does not enable the formation of fluoride apatite. The formation of hydroxyapatite bears no practical importance due to the insignificantly small amount of calcium. Thus, the formulation has no real significance for remineralisation. The study does not, however, provide any explanation or reveal the significance of the small amount of calcium present in the preparation.

In other known preparations, fluoride has been added to the lozenges in addition to xylitol. However, these preparations do not contain buffering compounds, which would increase the salivary buffer capacity. Similar formulations also appear in toothpastes, which are in the physical state of a paste and contain water. There is, for example, a toothpaste which contains bicarbonate and sodium fluoride.

The aim of the present invention is to eliminate the foregoing problems and to provide a new preparation which does not have the above-mentioned disadvantages. It is characteristic of the preparation relating to the invention

that the preparation is anhydrous, with the possible exception of crystal water, and by structure, for example a powder, solid tablet or other anhydrous composition,

that the preparation contains a remineralising component and a pH buffer component,

and that due to the effect of the water contained in the saliva or water added otherwise, the compounds in the preparation react with each other so as to bring about both a remineralisation reaction, correcting cavity formation in the teeth, and a pH buffering reaction preventing cavity formation in the teeth.

In addition to the effect of increasing salivary secretion, the preparation relating to the invention also has a more efficient buffer effect, and at the same time (in situ) a remineralising effect taking place through chemical reactions, by means of hydroxyapatite and fluoride apatite. The preparation relating to the invention is intended, above all, to compensate for the small amount of remineralising agents in the mouth of hyposalivation patients.

The preparation relating to the invention provides the following advantages with respect to earlier formulations:

Remineralisation takes place already in the mouth (in situ) and the fluoride dosed is bound in a useful form.

The other potential side effects of excess free fluoride are minimised.

The potential of remineralisation is markedly greater as compared with earlier preparations.

Due to the chemical reaction, the correct concentrations of buffering components are in exactly the correct chemical equilibrium ratio, that is, such as are characteristic of the surface-chemical interaction of the hard tissue.

The ingredients do not cause chemical corrosion.

The substances relating to the invention are known and acceptable as such. The combination relating to the invention also keeps well and does not contain easily fermenting components. The product increases salivary secretion, thus promoting chemical reactions for which the presence of water is essential. In a dry state, there is no reaction in the product.

The ingredients in the formulation relating to the invention have a buffering effect both before and after the chemical reaction. The reaction temperatures are, however, such that they have no significance on the temperature of the saliva.

Preferred embodiments of the invention are:

An inorganic or organic calcium compound having buffer capacity, e.g. (hydrogen) carbonate, carbonate, acetate, propionate, sorbate, ascorbate, aspartate, lysinate, gluconate, or lactate. Of these, the most advantageous economically is inorganic carbonate.

An alkali metal compound having buffering capacity in addition to the above calcium compounds. Such compounds are phosphates, pyrophosphates, polyphosphates and hydrogen phosphates. Of these, the most advantageous are different sodium and potassium phosphates and hydrogen carbonates, particularly disodium hydrogen phosphate.

An alkali metal fluoride, preferably sodium or potassium fluoride. Fluoride may also be bound in the same compound as phosphate, for example in the form of sodium monofluorophosphate.

According to a preferred embodiment of the invention, a dry compressed preparation, such as a tablet, is formed of the ingredients together with xylitol, which stimulates salivary secretion, the tablet containing the buffer compounds which participate in the chemical reaction, such as calcium, alkali metal, phosphate and fluoride compounds.

When the tablet relating to the invention comes into contact with water, or preferably with the saliva, the buffering effect is created immediately as the tablet disintegrates. With water as a medium, thermodynamically advantageous reactions take place between the compounds, the reactions settling into a state of equilibrium in the ambient condition. At the same time, new water-soluble buffering compounds are formed.

As a final result of the chemical reactions, either fluoride apatite or hydroxyapatite, or both, are formed of compounds characteristic of the invention, calcium, phosphates and fluoride. These are all structural substances essential to the hard tissue of the tooth.

The preparation relating to the invention differs from all other preparations in that the chemical reactions take place due to the effect of the saliva, while new buffer compounds resisting pH changes are at the same time formed from the starting materials.