Strontium-apatite cement preparations, cements formed therefrom, and uses thereof

• US 7,758,693 B2
• Filed: 01/26/2009
• Issued: 07/20/2010
• Est. Priority Date: 06/07/2002
• Status: Expired due to Term

• Current Assignee: Kyphon SARL (Medtronic Plc)
• Original Assignee: Kyphon SARL (Medtronic Plc)
• Inventors: Wenz, Robert
• Primary Examiner(s): KOSLOW, CAROL M
• Application Number:
  US12/359,907
• Publication Number:
  US 20090131949A1
• Time in Patent Office: 540 Days
• Field of Search: 623/23.62, 623/16.11, 106/690, 106/691
• US Class Current: 106/690
• 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: A61P 19/00 Drugs for skeletal disorders
• CPC Class Codes: A61P 19/08 for bone diseases, e.g. rachitism, Paget's disease
• CPC Class Codes: C04B 14/26 Carbonates
• CPC Class Codes: C04B 2111/00836 for medical or dental applications
• CPC Class Codes: C04B 28/344 the phosphate binder being present in the starting composition solely as one or more phosphates

Abstract

Calcium-strontium-hydroxyphosphate (strontium-apatite-) cement preparations are described, comprising a powder mixture, which contains molar quantities of the components calcium (Ca), strontium (Sr) and phosphate (P) in the mixture in the ranges 1.00<Ca/P≦1.50 and 0<Sr/P<1.5, together with an alkali salt or an ammonium salt of phosphoric acid, and with water and/or an aqueous solution. The powder mixture particularly contains, as the Ca-component, Ca₃(PO₄)₂ (TCP), and as the Sr-component SrHPO₄ and/or Sr₃(PO₄)₂ and optionally additional SrCO₃. As the aqueous mixing solution for the formation of the strontium-apatite cement, an aqueous solution of an alkali salt or an ammonium salt of the phosphoric acid is suitable.

Claims

1. A method for augmenting bone, the method comprising:

providing a powder mixture component comprising a tricalcium orthophosphate and a strontium orthophosphate, wherein the molar ratio of calcium phosphate is 1 to about 1.5, and a molar ratio of strontium to phosphate is not greater than about 1.5 and an aqueous component comprising a solution of a salt of an orthophosphoric acid selected from the group consisting of an alkali salt, an ammonium salt and a combination thereof;

combining the powder mixture and the aqueous component to form a bone substitute, wherein the bone substitute contains no more than trace amounts of magnesium ions; and

delivering the bone substitute to a site in contact with a bone.

2. The method for augmenting bone according to claim 1, further comprising forming the bone substitute into a predetermined shape.

3. The method for augmenting bone according to claim 1, further comprising closing a bone defect in a patient.

4. The method for augmenting bone according to claim 1, further comprising promoting anabolic activity in the bone of a patient.

5. The method for augmenting bone according to claim 1, wherein combining the powder mixture component and the aqueous component comprises forming a paste.

6. The method for augmenting bone according to claim 5, further comprising placing the paste into a mold and allowing the paste to harden into a molded shape.

7. The method for augmenting bone according to claim 6, further comprising inserting molded shape of bone substitute into a patient to augment a bone.

8. The method for augmenting bone according to claim 1, further comprising injecting the bone substitute into a site in a bone.

9. The method for augmenting bone according to claim 1, comprising filling a gap or defect in a bone.

10. The method for augmenting bone according to claim 1, further comprising adding a biological or pharmaceutical compound.

11. The method for augmenting bone according to claim 10, wherein adding a biological or pharmaceutical compound comprises adding a drug from the series of bone morphogenic proteins.

12. The method for augmenting bone according to claim 1, further comprising adding granular particles to the powder component and dissolving the granular particles in the aqueous component.

13. The method for augmenting bone according to claim 12, wherein the granular particles are about 10 μ

m to about 300 μ

m.

14. The method for augmenting bone according to claim 1, wherein the salt of an orthophosphoric acid is a primary or secondary sodium or potassium salt.

15. The method for augmenting bone according to claim 1, comprising delivering the bone substitute as a bone adhesive to a site in contact with a bone.

16. The method for augmenting bone according to claim 1, comprising delivering the bone substitute as a bone cement to a site in contact with a bone.

17. The method for augmenting bone according to claim 1, comprising delivering the bone substitute as a bone filler to a site in a bone.

18. The method for augmenting bone according to claim 11, further comprising promoting anabolic activity in the bone.