Acetabular shell system and method for making

• US 20060198943A1
• Filed: 03/02/2006
• Published: 09/07/2006
• Est. Priority Date: 03/03/2005
• Status: Active Grant

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Kumar, Mukesh
• Granted Patent: US 7,655,162 B2
• Time in Patent Office: Days
• US Class Current: 427/2.27
• CPC Class Codes: A61L 27/306 Other specific inorganic materials not covered by A61L27/303 - A61L27/32

Abstract

A method for forming an acetabular shell includes providing a working surface such as a mandrel, and spraying the working surface with a first layer of material having a first composition such as aluminum oxide. After a suitable thickness is generated, the spray composition is gradually changed to other compositions having desired particle sizes and distribution. In one example, the composition is changed to a mixture of aluminum oxide and titanium oxide and/or titanium. As thickness builds up, the relative amount of aluminum oxide is decreased such that the composition is all titanium and titanium oxide. After a desired thickness is generated, the acetabular shell is extracted off the mandrel.

Claims

1. A method for forming an acetabular cup comprising:

providing a working surface;

spraying a first layer of material having a first composition onto the working surface defining an acetabular shell; and

removing the acetabular shell from the working surface.

2. The method of claim 1, further comprising spraying a second layer of material having a second composition onto the first layer of material, the first and second layer of material collectively defining an acetabular shell.

3. The method of claim 2 wherein spraying the second layer of material comprises continuing the spraying of the first material while introducing a second material into the spray and defining a concentration of the first and second material.

4. The method of claim 3, further comprising continuing the spraying while reducing an amount of the first material in the concentration.

5. The method of claim 4 wherein the working surface comprises a mandrel having an outer convex surface, and wherein spraying the first layer includes spraying the first layer on the outer convex surface.

6. The method of claim 5, further comprising passing coolant through a coolant channel defined in the mandrel.

7. The method of claim 6 wherein the mandrel is formed from tungsten.

8. The method of claim 1 wherein providing the working surface further comprises spraying a mold relief agent onto the working surface.

9. The method of claim 3 wherein spraying the first layer of material comprises spraying a continuous layer of aluminum oxide.

10. The method of claim 9 wherein spraying the second layer of material comprises spraying a first mixture comprising aluminum oxide and at least one of titanium and titanium oxide.

11. The method of claim 10 wherein spraying the second layer of material further comprises spraying an outboard layer of titanium onto the first mixture.

12. The method of claim 11 wherein spraying the first and second layer of material comprises plasma spraying the first and second layer of material.

13. The method of claim 5, further comprising polishing an articulating surface defined on the first layer of material.

14. A method of forming an implant comprising:

providing a working surface;

spraying a first material onto the working surface;

concluding the spraying thereby defining an implant; and

removing the implant from the working surface.

15. The method of claim 14, further comprising spraying a second material onto the working surface.

16. The method of claim 15 wherein spraying the second material comprises continuing the spraying of the first material while introducing a second material into the spray and defining a concentration of the first and second material.

17. The method of claim 16, further comprising continuing the spraying while reducing an amount of the first material in the concentration.

18. The method of claim 17 wherein the working surface comprises a mandrel having an outer convex surface, and wherein spraying the first layer includes spraying the first layer on the outer convex surface.

19. The method of claim 18, further comprising passing coolant through a coolant channel defined in the mandrel.

20. The method of claim 19 wherein the mandrel is formed from tungsten.

21. The method of claim 18 wherein providing the working surface further comprises spraying a mold relief agent onto the working surface.

22. The method of claim 17 wherein spraying the first material comprises spraying a continuous layer of aluminum oxide.

23. The method of claim 22 wherein spraying the second material comprises spraying a first mixture comprising aluminum oxide and at least one of titanium and titanium oxide.

24. The method of claim 23 wherein spraying the second material further comprises plasma spraying an outboard layer of titanium onto the first mixture.

25. The method of claim 24 wherein spraying the first and second material comprises plasma spraying the first and second material.

26. The method of claim 14, further comprising polishing an articulating surface defined on the first material.

27. The method of claim 14 wherein the implant comprises an acetabular shell.

28. A method of making an implant comprising:

forming a ceramic shell having a first surface and a second surface;

locating the first surface of the ceramic shell onto a mounting instrument;

plasma spraying a layer of material onto the second surface of the ceramic shell; and

sintering the ceramic shell.

29. The method of claim 28, further comprising polishing the second surface of the ceramic shell.

30. The method of claim 28 wherein forming the ceramic shell comprises:

providing a first die defining a concave cavity having a textured die surface;

providing a second die defining a convex extension surface, the first and second die collectively forming a die cavity;

injecting a slurry of material into the die cavity; and

removing the ceramic shell from the die cavity.

31. The method of claim 30, further comprising coating the concave cavity with titanium powder.

32. The method of claim 30 wherein forming the ceramic shell comprises casting a ceramic shell having a textured outboard surface, the textured outboard surface adapted to accept the sprayed layer of material.

33. The method of claim 32 wherein plasma spraying the layer of material comprises spraying titanium oxide onto the second surface of the ceramic shell.