METHOD OF MAKING LOAD BEARING HYDROGEL IMPLANTS

• US 20090263446A1
• Filed: 11/18/2008
• Published: 10/22/2009
• Est. Priority Date: 02/06/2004
• Status: Active Grant

• Current Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Original Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Inventors: Kennedy, Stephen J., Boyan, Barbara D., Ku, David N., Guldberg, Robert E.
• Granted Patent: US 8,318,192 B2
• Time in Patent Office: Days
• US Class Current: 424/423
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/30784 Plurality of holes
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0023 differing in porosity
• CPC Class Codes: A61L 2430/38 for reconstruction of the spine, vertebrae or intervertebral discs
• CPC Class Codes: A61L 27/52 Hydrogels or hydrocolloids
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61P 19/02 for joint disorders, e.g. arthritis, arthrosis

Abstract

Implantable biomaterials, particularly hydrogel substrates with porous surfaces, and methods for enhancing the compatibility of biomaterials with living tissue, and for causing physical attachment between biomaterials and living tissues are provided. Also provided are implants suitable for load-bearing surfaces in hard tissue repair, replacement, or augmentation, and to methods of their use. One embodiment of the invention relates to an implantable spinal disc prosthesis.

Claims

1. A method of making a hydrogel having a hydrogel surface, comprising:

contacting solid objects with a liquid hydrogel;

allowing the liquid hydrogel to polymerize and crosslink while the solid objects are at least partially immersed along a surface region of the hydrogel; and

removing said solid objects from the polymerized and crosslinked hydrogel to form a plurality of superficial pores thereon;

wherein said superficial pores are located at or near said hydrogel surface; and

wherein said superficial pores do not extend throughout an entire depth of said hydrogel.

2. The method of claim 1, wherein the solid objects comprise polystyrene beads.

3. The method of claim 1, wherein the solid objects comprise a material selected from the group consisting of one or more of the following:

grit, sand, silicon, silica, and ultra-fine particulate matter.

4. The method of claim 1, wherein the solid objects have an average diameter of between about 1 to 100 micrometers.

5. The method of claim 1, wherein the solid objects have an average diameter of between about 5 to 50 micrometers.

6. The method of claim 1, wherein the solid objects have an average diameter of between about 10 and 30 micrometers.

7. The method of claim 1, wherein the superficial pores are within about 1 millimeter of the hydrogel surface.

8. The method of claim 1, wherein the superficial pores are within about 200 micrometers of the hydrogel surface.

9. The method of claim 1, wherein the solid objects are removed from the hydrogel using an organic solvent or washing.

10. The method of claim 1, wherein the hydrogel comprises polyvinyl alcohol.

11. The method of claim 1, wherein the hydrogel comprises a moisture content of at least about 5% w/w of the hydrogel.

12. The method of claim 1, wherein the hydrogel comprises a moisture content of at least about 30% w/w of the hydrogel.

13. A method of making an implantable hydrogel, comprising:

providing a liquid hydrogel;

allowing the liquid hydrogel to polymerize and crosslink so as to form a generally smooth hydrogel surface; and

abrading the hydrogel surface to form a plurality of superficial pores;

wherein said superficial pores are located at or near said hydrogel surface; and

wherein said superficial pores do not extend throughout an entire depth of said hydrogel.

14. The method of claim 13, wherein the superficial pores have an average cross-section of between about 1 to 100 micrometers.

15. The method of claim 13, wherein the superficial pores are within about 1 millimeter of the hydrogel surface.