Surface treatment for an implant surface

• US 9,131,995 B2
• Filed: 03/11/2013
• Issued: 09/15/2015
• Est. Priority Date: 03/20/2012
• 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): Tran, Binh X
• Application Number:
  US13/792,646
• Publication Number:
  US 20130248487A1
• Time in Patent Office: 918 Days
• Field of Search: 216/52, 216/53, 216/92, 216/100
• US Class Current: 1/1
• CPC Class Codes: A61C 13/0006 Production methods
• CPC Class Codes: A61C 2008/0046 Textured surface, e.g. roughness, microstructure A61C8/0013 takes precedence
• CPC Class Codes: A61C 8/0013 with a surface layer, coating
• CPC Class Codes: A61C 8/0037 Details of the shape
• CPC Class Codes: A61L 2400/12 Nanosized materials, e.g. nanofibres, nanoparticles, nanowires, nanotubes; Nanostructured surfaces
• 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 2430/02 for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 2430/12 for dental implants or prostheses
• CPC Class Codes: A61L 27/04 Metals or alloys
• CPC Class Codes: A61L 27/06 Titanium or titanium alloys
• CPC Class Codes: A61L 27/50 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: C23F 1/02 Local etching
• CPC Class Codes: C23F 1/38 for etching 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 including potassium hydroxide to produce a nanoscale roughened surface consisting of a web-like structure superimposed on the microscale roughened surface. The nanoscale roughened surface has a property that promotes osseointegration.

Claims

1. A method of forming an implant 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; and

immersing the microscale roughened surface into a solution including potassium hydroxide for about 30 minutes to about 90 minutes to produce a nanoscale roughened surface including a web-like structure superimposed on the microscale roughened surface, the solution having a concentration of about 12-32% w/w potassium hydroxide and a temperature of about 30°

C. to about 100°

C., the web-like structure being for contacting living bone.

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

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

4. 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

grit blasting the implant surface.

5. 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 implant surface.

6. The method of claim 5, wherein the act of roughening the implant surface comprises acid etching the implant surface with a solution including sulfuric acid and hydrochloric acid.

7. The method of claim 1, wherein the act of roughening the implant surface comprises:

grit blasting the surface to produce a first set of irregularities having peak-to-valley heights greater than about 10 microns; and

acid etching the surface to superimpose a second set of irregularities on the first set of irregularities, the second set of irregularities having peak-to-valley heights less than about 10 microns.

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

rinsing the nanoscale roughened surface in deionized water;

drying the nanoscale roughened surface.

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

10. The method of claim 1, wherein the potassium hydroxide has a molar concentration of about 5.9M.

11. The method of claim 1, further comprising depositing at least one salt on the implant surface.

12. A method of forming an implant 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 including potassium hydroxide for about 30 minutes to about 90 minutes to produce a nanoscale roughened surface including a web-like structure superimposed on the microscale roughened surface, the potassium hydroxide having a concentration of about 12-32% w/w and a temperature of about 30°

C. to about 100°

C., the web-like structure being for contacting living bone;

and

rinsing the nanoscale roughened surface in deionized water.

13. The method of claim 12, wherein the act of roughening the implant surface comprises grit blasting the implant surface.

14. The method of claim 12, wherein the act of roughening the implant surface comprises acid etching the implant surface with a solution including sulfuric acid and hydrochloric acid.

15. The method of claim 12, wherein the implant is made of a metal selected from the group consisting of titanium or alloys thereof.

16. The method of claim 12, wherein the implant is a dental implant.

17. The method of claim 12, further comprising the act of depositing discrete nanoparticles on the nanoscale roughened surface.

18. The method of claim 17, wherein the discrete nanoparticles are deposited using a solution including a 2-methoxyethanol solvent.

19. The method of claim 12, wherein the act of roughening the implant surface comprises acid etching the implant surface with a solution including sulfuric acid and hydrochloric acid.

20. The method of claim 12, wherein the potassium hydroxide has a molar concentration of about 5.9M.

21. A method of forming an implant to be implanted into living bone, the method comprising the acts of:

grit blasting the implant surface to create a first set of irregularities having peak-to-valley distances greater than about 10 microns;

acid etching the implant surface to create a second set of irregularities having peak-to-valley distances of less than ten microns with peak-to-peak distances of about 1 micron to about 3 microns;

immersing the implant surface into a solution including potassium hydroxide for about 30 minutes to about 90 minutes to produce a nanoscale roughened surface including a web-like structure superimposed on the first and second sets of irregularities, the potassium hydroxide solution having a concentration of about 12-32% w/w and a temperature of about 30°

C. to about 100°

C., the web-like structure being for contacting living bone;

depositing hydroxyapatite nanocrystals on the implant surface; and

applying a salt to the implant surface.

22. The method of claim 21, wherein the potassium hydroxide has a molar concentration of about 5.9M.