Dentin mineralizing agent and method for production thereof

Abstract

A dentin mineralizing agent comprising tetracalcium phosphate particles (A) and an alkali metal salt of phosphoric acid (B), wherein the dentin mineralizing agent contains the tetracalcium phosphate particles (A) in an amount of 1 to 80 parts by weight relative to 100 parts by weight of the whole amount of the dentin mineralizing agent, and the blended amount of the alkali metal salt of phosphoric acid (B) relative to 100 parts by weight of the tetracalcium phosphate particles (A) is 1 to 100 parts by weight. Thus is provided a dentin mineralizing agent by which a dense HAp is formed on a dentin surface and HAp is deposited to a deep portion of a dentinal tubule, so that it can close the dentinal tubule.

1 . A dentin mineralizing agent, comprising:
 at least one tetracalcium phosphate particle (A); and   an alkali metal salt of phosphoric acid (B),   wherein the agent comprises the at least one tetracalcium phosphate particle (A) in an amount of 1 to 80 parts by weight relative to 100 parts by weight of a whole amount of the agent, and   wherein a blended amount of the alkali metal salt of phosphoric acid (B) relative to 100 parts by weight of the at least one tetracalcium phosphate particle (A) is 1 to 100 parts by weight.   
     
     
         2 . The agent of  claim 1 , wherein the alkali metal salt of phosphoric acid (B) is at least one selected from the group consisting of disodium hydrogen phosphate and sodium dihydrogen phosphate. 
     
     
         3 . The agent of  claim 1 , further comprising:
 at least one acidic calcium phosphate particle (C).   
     
     
         4 . The agent of  claim 3 , wherein the acidic calcium phosphate particle (C) is at least one member selected from the group consisting of a dicalcium phosphate anhydrous [CaHPO 4 ] particle, a monocalcium phosphate anhydrous [Ca(H 2 PO 4 ) 2 ] particle, a tricalcium phosphate [Ca 3 (PO 4 ) 2 ] particle, an amorphous calcium phosphate [Ca 3 (PO 4 ) 2 .xH 2 O] particle, a calcium dihydrogen pyrophosphate [CaH 2 P 2 O 7 ] particle, a dicalcium phosphate dihydrate [CaHPO 4 .2H 2 O] particle, and a monocalcium phosphate monohydrate [Ca(H 2 PO 4 ) 2 .H 2 O] particle. 
     
     
         5 . The agent of  claim 3 , wherein a blending ratio (A/C) of the at least one tetracalcium phosphate particle (A) to the at least one acidic calcium phosphate particle (C) is from 40/60 to 60/40 in molar ratio. 
     
     
         6 . The agent of  claim 1 , further comprising:
 a fluorine compound (D).   
     
     
         7 . The agent of  claim 6 , wherein the fluorine compound (D) is sodium fluoride. 
     
     
         8 . The agent of  claim 1 , wherein an average particle diameter of the at least one tetracalcium phosphate particle (A) is 0.5 to 40 μm. 
     
     
         9 . The agent of  claim 1 , wherein an average particle diameter of the alkali metal salt of phosphoric acid (B) is 0.5 to 20 μm. 
     
     
         10 . The agent of  claim 1 , further comprising:
 at least one acid acidic calcium phosphate particle,   wherein an average particle diameter of the at least one acidic calcium phosphate particle (C) is 0.1 to 7 μm.   
     
     
         11 . The agent of  claim 1 , further comprising:
 at least one particle (E) of 0.002 to 2 μm in average particle diameter   wherein the particle comprises silica or at least one metal oxide.   
     
     
         12 . The agent of  claim 1 , in the form of a suspension prepared by adding 0.05 g of the agent into 200 g of pure water of 25° C.,
 wherein a free alkali metal ion concentration of the suspension at a time of 10 minutes after the adding is 0.2 to 100 mg/L. 
 
     
     
         13 . The agent of  claim 12 , wherein a standard deviation, σ, determined when an average of the free alkali metal ion concentration is expressed by d satisfies σ≦0.3d. 
     
     
         14 . The agent of  claim 12 , wherein the free alkali metal ion is a sodium ion. 
     
     
         15 . The agent of  claim 1 , wherein a dentin penetration inhibition ratio, achieved when one side of a 700 μm thick bovine tooth disc is treated with the agent satisfies formula (1)
   [1-(penetrated amount of a mineralized bovine tooth disc)/(penetrated amount of an unmineralized bovine tooth disc)]×100≧70  (I).
 
 
     
     
         16 . A tooth surface-treating material, comprising the agent of  claim 1 . 
     
     
         17 . A dentifrice, comprising the agent of  claim 1 . 
     
     
         18 . A chewing gum comprising the agent of  claim 1 . 
     
     
         19 . A dentinal hypersensitivity inhibitor comprising the agent of  claim 1 . 
     
     
         20 . A dentinal hypersensitivity inhibitor, comprising:
 the agent of  claim 1 ; and   at least one acidic calcium phosphate particle (C),   wherein the at least one tetracalcium phosphate particle (A) has an average particle diameter of 0.5 to 40 μm,   wherein a blended amount of the at least one tetracalcium phosphate particle (A) relative to 100 parts by weight of a whole amount of the inhibitor is 5 to 55 parts by weight, and   wherein the inhibitor is suitable for closing at least one dentinal tubule by rubbing a dentin surface therewith.   
     
     
         21 . A dentinal hypersensitivity inhibitor, comprising:
 the agent of  claim 1 ,   wherein when a suspension is prepared by adding 0.05 g of the inhibitor into 200 g of pure water of 25° C., a free alkali metal ion concentration of the suspension at a time of 10 minutes after the adding is 0.2 to 100 mg/L.   
     
     
         22 . The inhibitor of  claim 21 , further comprising:
 at least one acidic calcium phosphate particle (C).   
     
     
         23 . A method for producing a dentin mineralizing agent, the method comprising:
 mixing at least one tetracalcium phosphate particle (A), an alkali metal salt of phosphoric acid (B), and a liquid or aqueous paste comprising water as a main ingredient,   wherein 1 to 100 parts by weight of the alkali metal salt of phosphoric acid (B) is blended to 100 parts by weight of the tetracalcium phosphate particle (A), and   wherein a blended amount of the tetracalcium phosphate particle (A) relative to 100 parts by weight of a whole amount of the dentin mineralizing agent is adjusted to 1 to 80 parts by weight.   
     
     
         24 - 26 . (canceled) 
     
     
         27 . A method for producing a dentinal hypersensitivity inhibitor, the method comprising:
 mixing at least one tetracalcium phosphate particle (A), an alkali metal salt of phosphoric acid (B), at least one acidic calcium phosphate particles particle (C), and a liquid or aqueous paste comprising water as a main ingredient,   wherein the inhibitor is suitable for closing at least one dentinal tubule by rubbing a dentin surface therewith,   wherein the at least one tetracalcium phosphate particle (A) has an average particle diameter of 0.5 to 40 μm,   wherein 1 to 100 parts by weight of the alkali metal salt of phosphoric acid (B) is blended to 100 parts by weight of the at least one tetracalcium phosphate particle (A), and   wherein a blended amount of the at least one tetracalcium phosphate particle (A) relative to 100 parts by weight of a whole amount of the inhibitor is 5 to 55 parts by weight.   
     
     
         28 . The method of  claim 27 , further comprising, before the mixing,
 adding a liquid or aqueous past; comprising (i) water as a main ingredient and (ii) the at least one acidic calcium phosphate particle (C) to a powder or nonaqueous paste comprising the at least one tetracalcium phosphate particle (A) and the alkali metal salt of phosphoric acid (B).   
     
     
         29 . (canceled) 
     
     
         30 . A method for inhibiting dentinal hypersensitivity, the method comprising:
 rubbing a dentin surface with a dentinal hypersensitivity inhibitor,   wherein the inhibitor comprises at least one tetracalcium phosphate particle (A), an alkali metal salt of phosphoric acid (B), and at least one acidic calcium phosphate particle (C),   wherein the at least one tetracalcium phosphate particle (A) has an average particle diameter of 0.5 to 40 μm,   wherein a blended amount of the at least one tetracalcium phosphate particle (A) of 5 to 55 parts by weight relative to 100 parts by weight of a whole amount of the inhibitor, and   wherein a blended amount of the alkali metal salt of phosphoric acid (B) of 1 to 100 parts by weight relative to 100 parts by weight of the at least one tetracalcium phosphate particle (A).   
     
     
         31 - 36 . (canceled)