Calcium-containing restoration materials

• US 8,282,396 B2
• Filed: 05/03/2010
• Issued: 10/09/2012
• Est. Priority Date: 01/24/2001
• Status: Expired due to Term

• Current Assignee: ADA Foundation
• Original Assignee: ADA Foundation
• Inventors: Chow, Laurence C., Takagi, Shozo
• Primary Examiner(s): Ali, Shuangyi Abu
• Application Number:
  US12/772,843
• Publication Number:
  US 20100212545A1
• Time in Patent Office: 890 Days
• Field of Search: 433/215, 433/226, 106/690
• US Class Current: 433/215
• CPC Class Codes: A61K 2300/00 Mixtures or combinations of active ingredients, wherein at least one active ingredient is fully defined in groups A61K31/00 - A61K41/00
• CPC Class Codes: A61K 31/19 Carboxylic acids, e.g. valproic acid salicylic acid A61K31/60
• CPC Class Codes: A61K 33/06 Aluminium, calcium or magnesium; Compounds thereof , e.g. clay
• CPC Class Codes: A61K 33/42 Phosphorus; Compounds thereof
• CPC Class Codes: A61L 2400/06 Flowable or injectable implant compositions
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: A61L 27/46 with phosphorus-containing inorganic fillers
• CPC Class Codes: C04B 2111/00836 for medical or dental applications
• CPC Class Codes: C04B 24/02 Alcohols; Phenols; Ethers
• CPC Class Codes: C04B 24/045 Esters, e.g. lactones
• CPC Class Codes: C04B 24/06 containing hydroxy groups
• CPC Class Codes: C04B 24/14 Peptides; Proteins; Derivatives thereof
• CPC Class Codes: C04B 24/32 Polyethers, e.g. alkylphenol polyglycolether
• CPC Class Codes: C04B 24/38 Polysaccharides or derivatives thereof C04B24/243 takes precedence
• CPC Class Codes: C04B 24/383 Cellulose or derivatives thereof
• CPC Class Codes: C04B 28/344 the phosphate binder being present in the starting composition solely as one or more phosphates
• CPC Class Codes: C04B 40/065 Two or more component mortars

Abstract

A bone or dental implant material in the form of a paste includes a mixture of calcium phosphate and/or calcium-containing powders, liquid glycerol, organic acid and gelling agent. The paste is stable, resistant to washout and will harden upon exposure to water. Physical characteristics of the paste, including consistency, porosity, and hardening time, are controlled by the choice and ratio of constituents.

Claims

1. A method of preparing a paste for bone and tooth restoration, said method comprising the following steps:

(a) formulating a composition of components by mixing in a substantially anhydrous condition;

(i) a powdered calcium compound in the form of selectively sized powder particles, said particle size in the range of about 1 μ

m to 50 μ

m, said particles comprising a calcium compound selected from the group consisting of monocalcium phosphate monohydrate, monocalcium phosphate anhydrous, dicalcium phosphate anhydrous, dicalcium phosphate dehydrate, octacalcium phosphate, a-tricalcium phosphate, B-tricalcium phosphate, amorphous calcium phosphate, calcium deficient hydroxyapatite, non-stoichiometric hydroxyapatite, tetracalcium phosphate, CaSO₄, CASO₄.0.5H₂O, CASO₄.2H₂O, CaO, Ca(OH)₂, CaCO₃ and mixtures thereof;

(ii) a carboxylic acid for accelerating hardening of said composition when said composition is exposed to water at a delivery site, said acid comprising an acid selected from the group consisting of glycolic, citric, tartaric, malonic, malic, maleic acids and combinations thereof;

(ii) a non-toxic, non-aqueous water-miscible liquid; and

(iii) a gelling agent;

said powder to liquid mass ratio is at least about 1.5, said components blended to obtain a substantially homogeneous formable anhydrous paste mixture having a hardening time of less than about 35 minutes and a diametral tensile strength (DTS) in the range of about 2.7 to 3.8±

0.3 MPa within seven days after hardening; and

(b) storing said paste mixture under substantially anhydrous conditions.

2. The method of claim 1 wherein the gelling agent is selected from the group consisting of hydroxyl methyl cellulose, carboxymethyl cellulose, chitosan, collagen, gum, gelatin, alginate, and combinations thereof.

3. The method according to claim 1 wherein said miscible liquid is selected from the group consisting of glycerin, propylene glycol, poly(propylene glycol), poly(ethylene glycol) and mixtures thereof.

4. The method of claim 1 wherein the powder particle to liquid mass ratio is in the range of about 1.5 to 3.0.

5. The method of claim 1 wherein said non-toxic, non-aqueous water-miscible liquid is selected from the group consisting of glycerin, propylene glycol, poly (propylene glycol), poly(ethylene glycol) and mixtures thereof;

and

said gelling agent is selected from the group consisting of hydroxyl methyl cellulose, carboxymethyl cellulose, chitosan, collagen, gum, gelatin, alginate and combinations thereof.