Granted Patent B2

US 8,877,220 · App. 12/850,758 · Granted Nov 4, 2014

Abstract

Claims (25)

1. A compressed implant composite for repairing mineralized tissue, the composite comprising:

a cross-linked matrix formed of biopolymeric fibers, and a plurality of calcium- or silicate-based mineral particles dispersed in the matrix, wherein the matrix constitutes 4 to 80% by weight, the mineral particles constitute 20 to 96% by weight, and the composite is free of soluble collagen and is self-expandable to a volume 2 to 100 times of its compressed volume.

2. The composite of claim 1 , wherein the composite is expandable upon absorption of water.

3. The composite of claim 1 , wherein the composite is expandable upon absorption of body fluid.

4. The composite of claim 1 , wherein the composite is expandable to a volume 5 to 50 times of its compressed volume.

5. The composite of claim 1 , wherein the biopolymeric fibers are polypeptide fibers, polysaccharide fibers, or a combination thereof.

6. The composite of claim 5 , wherein the biopolymeric fibers are insoluble collagen fibers.

7. The composite of claim 1 , wherein the calcium-based mineral particles are calcium phosphate or calcium apatite.

8. The composite of claim 7 , wherein the calcium apatite is carbonate based apatite.

9. The composite of claim 1 , wherein the silicate-based mineral particles are silicate-based bioactive glass.

10. The composite of claim 9 , wherein the silicate-based bioactive glass is selected from the group consisting of 45S5 bioglass, 55SF bioglass, and S53P4 bioglass.

11. The composite of claim 1 , wherein the calcium- or silicate-based mineral particles have a particle size ranging from 0.001 mm to 5 mm.

12. The composite of claim 11 , wherein the calcium- or silicate-based mineral particles have a particle size ranging from 0.1 mm to 1.5 mm.

13. The composite of claim 1 , wherein the composite upon self-expansion has a density from 0.05 g/cm 3 to 0.8 g/cm 3 .

14. The composite of claim 13 , wherein the composite upon self-expansion has a density from 0.1 g/cm 3 to 0.6 g/cm 3 .

15. The composite of claim 1 , wherein the composite upon self-expansion has a pore size from 25 to 500 microns.

16. A method of preparing a bone implant composite of claim 1 , the method comprising: dispersing biopolymeric fibers in an aqueous solution, to form a suspension, the biopolymeric fibers being free of soluble collagen; homogenizing the suspension; mixing the homogenized suspension with a plurality of calcium-or-silicate-based mineral particles to form a mixture; freeze-drying the mixture; crosslinking the freeze-dried mixture to form a crosslinked composite; and compressing the crosslinked composite.

17. The method of claim 16 , further comprising, after the crosslinking step and before the compressing step, hydrating the crosslinked composite.

18. The method of claim 17 , further comprising, after the compressing step, freeze-drying the compressed composite.

19. The method of claim 16 , wherein the biopolymeric fibers are polypeptide fibers, polysaccharide fibers, or a combination thereof.

20. The method of claim 19 , wherein the biopolymeric fibers are insoluble collagen fibers.

21. The method of claim 16 , wherein the calcium-based mineral particles are calcium phosphate or calcium apatite.

22. The method of claim 21 , wherein the calcium apatite is carbonate based apatite.

23. The method of claim 16 , wherein the silicate-based mineral particles are silicate-based bioactive glass.

24. The method of claim 23 , wherein the silicate-based bioactive glass is 45S5 bioglass.

Assignments (10)