Titanium nano-scale etching on an implant surface

• US 8,641,418 B2
• Filed: 03/29/2011
• Issued: 02/04/2014
• Est. Priority Date: 03/29/2010
• Status: Active Grant

• Current Assignee: Biomet 3i LLC (Zimvie Incorporated)
• Original Assignee: Biomet 3i LLC (Zimvie Incorporated)
• Inventors: Mayfield, Robert L., Towse, Ross W.
• Primary Examiner(s): Deo, Duy
• Application Number:
  US13/074,670
• Publication Number:
  US 20110233169A1
• Time in Patent Office: 1,043 Days
• Field of Search: None
• US Class Current: 433/173
• CPC Class Codes: A61C 13/00 Dental prostheses; Making same tooth crowns for capping teeth A61C5/70; dental implants A61C8/00
• CPC Class Codes: A61C 2008/0046 Textured surface, e.g. roughness, microstructure A61C8/0013 takes precedence
• CPC Class Codes: A61C 8/00 Means to be fixed to the jaw-bone for consolidating natural teeth or for fixing dental prostheses thereon; Dental implants; Implanting tools fastening of peg-teeth in the mouth A61C13/30
• CPC Class Codes: A61C 8/0012 characterised by the material or composition, e.g. ceramics, surface layer, metal alloy use of specific materials A61K6/00
• CPC Class Codes: A61C 8/0013 with a surface layer, coating
• CPC Class Codes: A61C 8/0015 being a conversion layer, e.g. oxide layer
• CPC Class Codes: A61C 8/0022 Self-screwing A61C8/0028 takes precedence
• CPC Class Codes: A61C 8/0037 Details of the shape
• CPC Class Codes: A61L 2400/18 Modification of implant surfaces in order to improve biocompatibility, cell growth, fixation of biomolecules, e.g. plasma treatment
• CPC Class Codes: A61L 27/04 Metals or alloys
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C23F 1/00 Etching metallic material by chemical means manufacture of printing surfaces B41C; manufacture of printed circuits H05K
• CPC Class Codes: C23F 1/26 for etching refractory metals
• CPC Class Codes: C23F 1/30 for etching other metallic material
• CPC Class Codes: C23F 1/38 for etching refractory metals
• CPC Class Codes: C23G 1/106 refractory metals

Abstract

A method of forming an implant to be implanted into living bone is disclosed. The method comprises the act of roughening at least a portion of the implant surface to produce a microscale roughened surface. The method further comprises the act of immersing the microscale roughened surface into a solution containing hydrogen peroxide and a basic solution to produce a nanoscale roughened surface consisting of nanopitting superimposed on the microscale roughened surface. The nanoscale roughened surface has a property that promotes osseointegration.

Claims

1. A method of forming an implant with a surface topography, the implant with the surface topography to be implanted into living bone, the method comprising the acts of:

roughening at least a portion of the implant surface to produce a microscale roughened surface;

immersing the microscale roughened surface into a solution containing hydrogen peroxide and a basic solution to produce the surface topography including a nanoscale roughened surface, the nanoscale roughened surface including nanopitting superimposed on the microscale roughened surface; and

rinsing the surface topography in deionized water.

2. The method of claim 1, wherein the implant is made of a metal selected from the group consisting of tantalum, cobalt, chromium, titanium, stainless steel, or alloys thereof.

3. The method of claim 1, wherein the implant is a dental implant.

4. The method of claim 3, wherein the portion of the implant surface is a threaded bottom portion for facilitating bonding with bone.

5. The method of claim 1, wherein the implant is made of titanium and the act of roughening the implant surface comprises grit blasting the surface.

6. The method of claim 1, wherein the implant is made of titanium and the act of roughening the implant surface comprises:

removing a native oxide layer from the implant surface; and

acid etching the resulting surface.

7. The method of claim 6, wherein the act of roughening the implant surface comprises acid etching the implant surface with a solution containing sulfuric acid and hydrochloric acid.

8. The method of claim 1, wherein the basic solution is a sodium hydroxide solution.

9. The method of claim 1, wherein the basic solution is a potassium hydroxide solution.

10. The method of claim 9, wherein the potassium hydroxide solution has a concentration of about 3-5% w/w and the hydrogen peroxide has a concentration of about 13-22% w/w.

11. The method of claim 9, wherein the potassium hydroxide solution has a concentration of about 1-6% w/w and the hydrogen peroxide has a concentration of about 1-6% w/w.

12. The method of claim 1, wherein the basic solution has a pH between about 7 to about 14.

13. The method of claim 1, wherein the nanopitting is in the 1-100 nanometer range.

14. The method of claim 1, further comprising the acts of:

passivating the nanoscale roughened surface with nitric acid;

re-rinsing the nanoscale roughened surface in deionized water; and

drying the nanoscale roughened surface.

15. The method of claim 14, further comprising the act of sterilizing the implant.

16. The method of claim 1, further comprising the act of depositing discrete nanoparticles on the nanoscale roughened surface.

17. The method of claim 1, further comprising the act of applying a sodium lactate coating on the nanoscale roughened surface.

18. The method of claim 1, wherein the act of roughening the implant surface produces irregularities with peak-to-valley heights of less than about 10 microns and peak-to-peak distances of less than about 3 microns.

19. A method of forming an implant with a nanoscale roughened surface, the implant with the nanoscale roughened surface to be implanted into living bone, the method comprising the acts of:

removing a native oxide layer from at least a portion of the implant surface;

roughening at least the portion of the implant surface to produce a microscale roughened surface;

rinsing the microscale roughened surface in deionized water;

immersing the microscale roughened surface into a solution containing hydrogen peroxide and a basic solution at a high pH level to produce the nanoscale roughened surface including nanopitting superimposed on the microscale roughened surface;

passivating the nanoscale roughened surface with nitric acid; and

rinsing the nanoscale roughened surface in deionized water.

20. The method of claim 19, wherein the act of roughening the implant surface comprises grit blasting the implant surface.

21. The method of claim 19, wherein the act of roughening the implant surface comprises acid etching the implant surface with a solution containing sulfuric acid and hydrochloric acid.

22. The method of claim 19, wherein the implant is made of a metal selected from the group consisting of tantalum, cobalt, chromium, titanium, stainless steel, or alloys thereof.

23. The method of claim 19, wherein the implant is a dental implant.

24. The method of claim 19, wherein the basic solution is a sodium hydroxide solution.

25. The method of claim 19, wherein the basic solution is a potassium hydroxide solution having a concentration of about 3-5% w/w and the hydrogen peroxide has a concentration of about 13-22% w/w.

26. The method of claim 19, wherein the basic solution is a potassium hydroxide solution having a concentration of about 1-6% w/w and the hydrogen peroxide has a concentration of about 1-6% w/w.

27. The method of claim 19, further comprising the act of depositing discrete nanoparticles on the nanoscale roughened surface.

28. The method of claim 19, wherein the act of roughening the implant surface produces irregularities with peak-to-valley heights of less than about 10 microns and peak-to-peak distances of less than about 3 microns.