Biomedical implantable material and methods of producing the same

• US 8,454,707 B2
• Filed: 04/05/2010
• Issued: 06/04/2013
• Est. Priority Date: 04/03/2009
• Status: Active Grant

• Current Assignee: University of Maryland
• Original Assignee: University of Maryland
• Inventors: Ankem, Sreeramamurthy
• Primary Examiner(s): Sweet, Thomas J
• Assistant Examiner(s): STEWART, JASON-DENNIS NEILKEN
• Application Number:
  US12/754,309
• Publication Number:
  US 20110009965A1
• Time in Patent Office: 1,156 Days
• Field of Search: 623 2353- 2355, 623/1.15, 623/1.39, 623/1.4
• US Class Current: 623/23.55
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2002/3084 Nanostructures
• CPC Class Codes: A61F 2002/3092 having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/30978 using electrical discharge machining [EDM]
• CPC Class Codes: A61F 2310/00011 Metals or alloys
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61L 27/06 Titanium or titanium alloys
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: B22F 2003/241 Chemical after-treatment on the surface
• CPC Class Codes: B22F 2003/248 Thermal after-treatment
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 3/10 Sintering only
• CPC Class Codes: B23K 2103/14 Titanium or alloys thereof
• CPC Class Codes: B23K 26/355 Texturing
• CPC Class Codes: C22C 1/08 Alloys with open or closed pores
• CPC Class Codes: Y10T 428/249921 Web or sheet containing structurally defined element or component
• CPC Class Codes: Y10T 428/26 Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension

Abstract

The present invention relates to improved biomedical implantable material comprising a plurality of pores, of which one or more of the pores are interconnected below the surface of the material. The improved biomedical implantable material may be used in biomedical implant devices such as orthopedic implants, spinal implants, neurocranial implants, maxillofacial implants, and joint replacement implants. The present invention also relates to a method of preparing an improved biomedical implantable material, comprising subjecting an implantable material to a pore-forming treatment and optionally further subjecting the material to a surface-modifying treatment. The biomedical implantable material may be used in other applications, which as applications where two surfaces are contacted and bonding between the surfaces is required.

Claims

1. A biomedical implantable material comprising a plurality of pores, wherein the pores are formed from the surface of the material into the material and two or more of the pores are directly connected below the surface of the material and wherein one or more of the pores are at an angle of about 90°

relative to the surface of the material and the other pores are at an angle other than 90°

relative to the surface of the material.

2. The biomedical implantable material of claim 1, wherein the pores have a diameter of 200 to 400 microns.

3. The biomedical implantable material of claim 1, wherein the pores have a depth of 600 to 900 microns.

4. The biomedical implantable material of claim 1, wherein 90% or more of the pores are interconnected to one or more other pores below the surface of the materials.

5. The biomedical implantable material of claim 1, wherein the pores are uniformly spaced from each other.

6. The biomedical implantable material of claim 1, wherein the material comprises one or more components selected from the group consisting of:

titanium, cobalt, chromium, tantalum, stainless steel, nickel, zirconium, vanadium, aluminum, and alloys thereof.

7. The biomedical implantable material of claim 1, wherein the material comprises titanium or alloys of titanium.

8. A biomedical implant device comprising the biomedical implantable material of claim 1.

9. The biomedical implant device of claim 8, wherein the device is selected from the group consisting of:

orthopedic implants for the hips, knees, acetabular cups, ankles, or shoulders;

spinal implants;

neurocranial implants;

maxillofacial implants;

dental implants; and

joint replacement implants.

10. A process for preparing an improved biomedical implantable material, comprising subjecting an implantable material to a pore-forming treatment to form a plurality of pores, wherein the pores are formed from the surface of the material into the material in such a manner that two or more of the pores are directly connected below the surface of the implantable material and one or more of the pores are at an angle of about 90°

relative to the surface of the material and the other pores are at an angle other than 90°

relative to the surface of the material.

11. The process of claim 10, further comprising subjecting the implantable material to a surface-modifying treatment.

12. The process of claim 11, wherein the surface-modifying treatment comprises thermal oxidation.

13. The process of claim 12, wherein the thermal oxidation occurs at a temperature of about 100°

C. to about 300°

C.

14. The process of claim 12, wherein the thermal oxidation comprises subjecting the material with forced air, wherein the air is atmospheric air, commercially pure oxygen, or oxygen-enriched air.

15. The process of claim 12, wherein the thermal oxidation occurs over a time period of about 5 to about 60 minutes.

16. The process of claim 10, wherein the pore-forming treatment is selected from the group consisting of:

electrical discharge machining, plasma processing, mechanical drilling, sintering, laser etching, plasma gas etching, and gritt blasting.

17. The process of claim 10, wherein the pore-forming treatment comprises electrical discharge machining.