Magnesium ammonium phosphate cement composition

• US 7,942,963 B2
• Filed: 03/19/2010
• Issued: 05/17/2011
• Est. Priority Date: 07/03/2000
• Status: Expired due to Fees

• Current Assignee: Kyhon SARL
• Original Assignee: Kyhon SARL
• Inventors: Zimmermann, Michael
• Primary Examiner(s): MARCANTONI, PAUL D
• Application Number:
  US12/727,643
• Publication Number:
  US 20100173846A1
• Time in Patent Office: 424 Days
• Field of Search: 106/690
• US Class Current: 106/690
• CPC Class Codes: A61B 17/00491 Surgical glue applicators surgical adhesives A61L24/00; two-component delivery syringes A61M5/19
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30535 Special structural features of bone or joint prostheses not otherwise provided for
• CPC Class Codes: A61F 2002/4631 the prosthesis being specially adapted for being cemented
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2250/0058 Additional features; Implant or prostheses properties not otherwise provided for
• 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: A61K 45/06 Mixtures of active ingredients without chemical characterisation, e.g. antiphlogistics and cardiaca
• CPC Class Codes: A61K 6/17 Particle size
• CPC Class Codes: A61K 6/838 Phosphorus compounds, e.g. apatite
• CPC Class Codes: A61K 6/864 Phosphate cements apatite A61K6/838
• CPC Class Codes: A61K 6/867 Ammonium cements
• CPC Class Codes: A61L 24/0036 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 24/02 containing inorganic materials
• CPC Class Codes: A61L 2430/02 for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61P 19/00 Drugs for skeletal disorders
• CPC Class Codes: C04B 12/025 : Phosphates of ammonium or of the alkali or alkaline earth metals
• CPC Class Codes: C04B 14/22 : Glass ; Devitrified glass
• CPC Class Codes: C04B 14/26 : Carbonates
• CPC Class Codes: C04B 14/30 : Oxides other than silica ferrites C04B14/363
• CPC Class Codes: C04B 14/304 : Magnesia
• CPC Class Codes: C04B 14/366 : Phosphates, e.g. apatite
• CPC Class Codes: C04B 20/008 : Micro- or nanosized fillers, e.g. micronised fillers with particle size smaller than that of the hydraulic binder colloidal silica C04B14/062 ; silica fume C04B18/146
• CPC Class Codes: C04B 2103/0009 : Inorganic ammonium compounds
• CPC Class Codes: C04B 2111/00206 : Compositions defined by their elemental analysis
• CPC Class Codes: C04B 2111/00836 : for medical or dental applications
• CPC Class Codes: C04B 22/06 : Oxides, Hydroxides C04B22/0013 takes precedence
• CPC Class Codes: C04B 22/062 : of the alkali or alkaline-earth metals
• CPC Class Codes: C04B 22/064 : of the alkaline-earth metals
• CPC Class Codes: C04B 22/10 : containing carbon in the anion
• CPC Class Codes: C04B 22/124 : Chlorides of ammonium or of the alkali or alkaline earth metals, e.g. calcium chloride
• CPC Class Codes: C04B 22/126 : Fluorine compounds, e.g. silico-fluorine compounds
• CPC Class Codes: C04B 22/142 : Sulfates
• CPC Class Codes: C04B 22/143 : Calcium-sulfate
• CPC Class Codes: C04B 22/16 : containing phosphorus in the anion, e.g. phosphates
• CPC Class Codes: C04B 24/10 : Carbohydrates or derivatives thereof
• CPC Class Codes: C04B 24/282 : Polyurethanes; Polyisocyanates
• CPC Class Codes: C04B 28/34 : containing cold phosphate binders
• 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 28/346 : the phosphate binder being present in the starting composition as a mixture of free acid and one or more phosphates
• CPC Class Codes: C04B 28/348 : the starting mixture also containing one or more reactive oxides

Abstract

This invention relates to a cement, which comprises in its main phase of microcrystalline magnesium ammonium phosphate and nanoapatite after hardening and thus at the same time has considerable strength. The material is biologically degradable and is suitable for application in tooth cements, as bone replacement, as bone filler, as bone cement or as bone adhesive.

Claims

1. A magnesium ammonium phosphate cement produced by a process comprising:

providing an ammonium salt;

providing a powder mixture having molar quantities of the components calcium (Ca), magnesium (Mg) and orthophosphate (P) in the mixture in the ranges 1.00<

Ca/P<

1.50 and 0<

Mg/P<

0.50;

mixing the ammonium salt and the powder mixture with a mixing liquid to form a paste and achieve an uniform distribution of the liquid in the powder mixture; and

reacting the components therein to form a microcrystalline magnesium ammonium phosphate cement.

2. The magnesium ammonium phosphate cement of claim 1, further comprising providing a strontium salt.

3. The magnesium ammonium phosphate cement of claim 2, wherein the strontium salt comprises SrCO₃.

4. The magnesium ammonium phosphate cement of claim 3, comprising providing the SrCO₃ in a quantity of 0.01 to 10 wt. % based on the total weight of the preparation.

5. The magnesium ammonium phosphate cement of claim 1, comprising providing the ammonium salt as (NH₄)₂HPO₄.

6. The magnesium ammonium phosphate cement of claim 1, comprising reacting the components therein between about 2.5 to about 60 minutes (measured according to ASTM C266-89) to form the magnesium ammonium phosphate cement.

7. The magnesium ammonium phosphate cement of claim 1, further comprising providing granular particles.

8. The magnesium ammonium phosphate cement of claim 7, wherein the granular particles are slightly soluble in aqueous liquids.

9. The preparation of claim 7, comprising providing granular particles having a diameter of between 10 μ

m and 300 μ

m.

10. The magnesium ammonium phosphate cement of claim 7, wherein the granular particles are a substance selected from the group consisting of NaCl, sugars, CaSO₄, β

-TCP, polylactides, polyglycolides or polylactide/polyglycolide copolymer, CaCO₃ and CaHPO₄.

11. The magnesium ammonium phosphate cement of claim 1, further comprising adding a pharmaceutical and/or a bioactive active ingredient.

12. The magnesium ammonium phosphate cement of claim 11, wherein the pharmaceutical and/or a bioactive active ingredient comprises a component selected from the group consisting of antibiotics, cytostatic agents, analgesics, disinfectants, growth factors, proteins and elastin inhibitors.

13. The magnesium ammonium phosphate cement of claim 1, comprising providing a powder mixture having α

-tricalcium phosphate.