DENTURE DECALCIFYING AND CLEANSING PREPARATIONS

Abstract: Method of decalcifying and cleansing dentures and other substrates having calcium deposits formed thereon. The method includes the step of applying to the dentures or other substrates a compound selected from the group consisting of malic, tartaric, mesotartaric and citric acids. Preferably, however, citric acid is used in combination with sodium bicarbonate.

Description: "DENTURE DECALCIFYING AND CLEANSING PREPARATIONS" This invention relates to a preparation for decalcifying and cleansing dentures and other substrates having calcium deposits formed thereon. Hitherto dentures have been subjected to many different denture cleansing preparations but have met with little success. The main reason for this is that in relation to dentures, these have calcium deposits (i.e. "calculus") which build up and are difficult to remove. Calculus is a hard yellowish substance that is of alkaline nature which is removed from "natural teeth" by mechanical means. It is therefore an object of the invention to provide a method and preparation for the cleansing of artificial dentures and other substrates which have calcium containing deposits formed thereon. The method of the invention includes the step of applying to the dentures a compound selected from the group consisting of malic, tartaric, mesotartaric and citric acids so as to remove calcium deposits formed thereon. The denture cleansing preparation of the invention is a composition containing malic, tartaric, mesotartaric or citric acids. Preferably the composition also includes an alkali salt which is preferably sodium bicarbonate. The most preferred hydroxy acid which is used in relation to the present invention is citric acid because of its tribasic nature. While the other acids such as malic and tartaric may be used with good effectiveness, these acids are dibasic and as such will not prove as effective as citric acid. In relation to citric acid, it has been found in accordance with the invention that when it is combined with sodium bicarbonate there is provided a most effective composition for cleansing and decalcifying artificial dentures . Citric acid has the formula: H 2 C ■ COOH HOCH- -COOH H 2 C ■COOH and when reacted with calcium oxide the following reaction occurs: CH. -COOH CH(OH)COOH 3 CaO CH, -COOH Calcium Citrate + 3 H 2 0 When calcium carbonate is reacted with citric acid the following reaction also occurs: 2 Citric Acid + 3 Ca CO. -5* Calcium Citrate + 3 Water + 3 C0 2 When tartaric acid is reacted with calcium oxide, the following reaction occurs: CH (OH) COOH CH (OH)—COO. + CaO- Ca + H 2 0 CH (OH) COOH CH (OH)-COO^ When tartaric acid is reacted with calcium carbonate, the following reaction occurs: Tartaric Acid + Ca CO. -> Calcium Tartrate + wate When malic acid is reacted with calcium oxide, the following reaction occurs : CH (OH) — COOH CH (OH) — COO* + CaO * > ■ Ca CH 2 — COOH . CH 2 — COO + H 2 0 When malic acid is reacted with calcium carbonate the following reaction occurs: Malic Acid + Ca CO-. -^ Calcium Malate 0 + Water + C0 2 The abovementioned reactions illustrate the mechanism behind the invention and show that the above¬ mentioned hydroxy acids will react with both calcium oxide or lime (i.e. CaO H„0 or Ca (OH)-) and calcium carbonate 5 which are common components of calculus and thus form the calcium salt of the acid. Because citric acid has more - COOH groupings than the other two acids referred to (i.e. malic acid and tartaric acid) it takes up three calcium atoms in the formation of calcium citrate as shown u and hence the reaction is a lot quicker and more thorough than the formation of calcium malate and calcium tartrate, where only one calcium atom is taken up. This is why citric acid is much preferred to the other hydroxy acids. The addition of sodium bicarbonate (Na HCO-,) ^ is useful as it promotes an effervescent action because it reacts with the citric acid to release carbon dioxide. This effervescent action helps in releasing food particles trapped in inaccessible locations within the mouth and breaks up tablets incorporating the composition of the 0 invention into a homogeneous solution. In accordance with the invention the hydroxy acid may be used per se but it is much preferred to use sodium bicarbonate in conjunction therewith for the reasons discussed above. 5 Also if hydrous citric acid (i.e. having one molecule of waterl is mixed with sodium bicarbonate initially, the resulting mixture f ses, due to physical interaction due to the water present which is provided by the water molecules in the hydrous citric acid. If the mixture is then dried, such as by blowing hot air there¬ through with simultaneous agitation of the particles in the mixture, a dry granular residue is obtained containing anhydrous citric acid. Alternatively anhydrous citric acid may be obtained commercially to which is added sodium bicarbonate plus other desired components. This latter procedure is preferable because it is not necessary to carry out the drying step referred to above. Subsequently the mixture may be compressed and thus tablets may be formed by any suitable method known per se. The tablets are stable if stored in dry conditions. No chemical reaction will occur until water is mixed with the components of the mixture (i.e. citric acid and sodium bicarbonate) for the purpose of decalcification and cleansi of dentures. Then an effervescent reaction occurs with the subsequent rapid removal of the calculus from the artificial dentures. In relation to the preferred citric acid - sodium bicarbonate composition, other additives may be included such as colouring components and aromatic components. Preferably the composition contains a proportion of sodium bicarbonate of around 5 to 25%, based on the weight of the composition and 75 to 95% of citric acid. More suitably the composition comprises 80% citric acid, 15% sodium bicarbonate, 4% of colouring matter and 1% of aromatic material. All these proportions are calculated on a weight basis. EXAMPLE In one example of the invention , a composition comprising 24.8g. of citric acid, 4.65g. of sodium bicarbonate, 1.24g. of colouring matter and 0.31g. of aromatic component was found to be useful. As described previously, the citric acid neutralizes and decalcifies the calcium deposits while the effervescent effect provided by sodium bicarbonate helps activate the cleansing action of the citric acid and also remove food deposits. Colouring matter such as a vegetable dye help distinguish the cleansing composition from other types and also assists in covering up or disguising of debris liberated by the reaction taking place. The aromatic component such as peppermint provides a deodorant type of action. Cold water is much preferred to hot water for use in the invention as citric acid reacts more effective¬ ly in cold water. Also calcium citrate is less soluble in hot water than in cold water. Hot water also causes premature deterioration in the dentures such as bleaching and weakening of the acrylic material dentures are made from. In comparison with a conventional product which requires to be used every night, the composition of the invention only requires usage once a week. Used in this manner, the dentures will have little or no calculus formation and will be kept in a sterile condition. A preferred colouring material for use in the invention is prepared by mixing sucrose with a dye in combination with sodium bicarbonate and water. The mixture may be heated slowly and steam is evolved. The colour of dye is absorbed by the sucrose. Suggested proportions are sucrose (one ounce), dye (50mg.) and sodium bicarbonate 4.65g. A preferred dye is a vegetable dye such as G.B. Pillar-Box Red No. C931. A suitable aromatic additive may be prepared by mixing peppermint essence with sucrose and sodium bicarbonate. When heated to expell moisture, the sucrose absorbs the peppermint and bicarbonate to form granular crystals. Suggested proportions are sucrose (one ounce) , 3ml. of peppermint essence and 4.65g. of sodium bicarbonate

Claims: CLAIMS : 1. A method of decalcifying and cleansing dentures and other substrates having calcium deposits formed thereon including the step of applying to the dentures or other substrates a compound selected from the group consisting of malic, tartaric, mesotartaric and citric acids. 2. A method as claimed in claim 1 wherein the compound is citric acid. 3. A method as claimed in claim 1 or 2 wherein a composition is applied to the dentures or other substrates which includes the compound and sodium bicarbonate. 4. A method as claimed in claim 3 wherein the composition includes hydrous citric acid mixed with sodium carbonate which is subsequently dried. 5. A method as claimed in claim 3 wherein the composition includes anhydrous citric acid. 6. A method as claimed in claim 4 or 5 wherein the composition includes 5 to 25% of sodium bicarbonate and 75 to 95% of citric acid. 7. A method as claimed in claim 6 wherein there ' is utilized 80% of citric acid and 15% of sodium bicarbonate. 8. A composition for decalcifying and cleansing dentures and other substrates having calcium deposits formed thereon including a compound selected from the group consisting of malic, tartaric, mesotartaric and citric acids and sodium bicarbonate. 9. A composition as claimed in claim 8 wherein the compound is citric acid. 10. A composition as claimed in claim 9 including 5 to 25% based on the weight of the composition of sodium bicarbonate and 75 to 95% based on the weight of the composition of citric acid. 11. A composition as claimed in claim 10 wherein there is included 80% of citric acid and 15% of sodium bicarbonate with the remainder of the composition OMPI WIPO y, being formed from pigments and aromatic material.

Inventors: POWELL F
Applicants: POWELL F
Application year: 1981
Main classification: A61K7
IPC codes: A61K8, A61Q11, C11D7