SOFT PROSTHESIS SHELL TEXTURING METHOD

• US 20090118829A1
• Filed: 10/30/2008
• Published: 05/07/2009
• Est. Priority Date: 11/05/2007
• Status: Active Grant

• Current Assignee: Allergan, Inc. (Canada) (Abbvie Incorporated)
• Original Assignee: Allergan, Inc. (Canada) (Abbvie Incorporated)
• Inventors: Dang, Loantrang, Powell, Thomas E.
• Granted Patent: US 8,313,527 B2
• Time in Patent Office: Days
• US Class Current: 623/8
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence
• CPC Class Codes: A61F 2/12 Mammary prostheses and implants
• CPC Class Codes: A61F 2002/0086 for preferentially controlling or promoting the growth of specific types of cells or tissues of bone tissue onto implantable joints A61F2002/3093

Abstract

A method of texturing a soft prosthetic implant shell, such as a silicone breast implant shell. A soft prosthetic implant with a textured external surface layer of silicone elastomer and having an open-cell structure is made by adhering and then dissolving round salt crystals. The resulting roughened surface has enhanced physical properties relative to surfaces formed with angular salt crystals. An implant having such a textured external surface layer is expected to help prevent capsular contraction, to help prevent scar formation, and to help in anchoring the implant within the body.

Claims

1. A process for forming a soft prosthetic implant, comprising:

forming a flexible shell;

adhering on the exterior of the flexible shell a substantially even distribution of rounded salt particles;

curing the flexible shell with the rounded salt particles adhered thereto; and

exposing the flexible shell to an aqueous solvent for the rounded salt particles for a sufficient amount of time to dissolve the rounded salt particles and form an open-pored structure on the exterior of the flexible shell.

2. The process of claim 1, wherein the rounded salt particles are sodium chloride crystals.

3. The process of claim 1, wherein the flexible shell is formed of a silicone elastomer.

4. The process of claim 1 further comprising the step of applying a tack coat layer to the flexible shell prior to the step of adhering.

5. The process of claim 1, further comprising the step of applying an overcoat to the distribution of rounded salt particles prior to the step of curing.

6. The process of claim 1, wherein the rounded salt particles have a maximum particle size range selected from a group of ranges consisting of (1) a range between about 180 microns and about 425 microns, (2) a range between about 425 microns and about 850 microns, and (3) a range between about 850 microns and about 1450 microns.

7. The process of claim 6 wherein about 90% of the rounded salt particles are in the selected particle size range.

8. The process of claim 1, wherein the prosthetic implant is a breast implant and the flexible shell is shaped accordingly.

9. The process of claim 1, wherein the step of forming the flexible shell comprises dipping a mandrel into a liquid dispersion of an elastomeric material.

10. The process of claim 1, wherein the step of forming the flexible shell comprises rotationally molding the shell.

11. The process of claim 1, wherein the step of adhering comprises dipping the flexible shell into a liquid containing the rounded salt particles.

12. The process of claim 11, further comprising the step of applying a tack coat layer onto the flexible shell prior to the step of dipping the flexible shell into a liquid containing the rounded salt particles.

13. A soft prosthetic breast implant, formed by a process comprising:

forming a flexible shell of silicone elastomer in the shape of a breast implant;

adhering on the exterior of the flexible shell an even distribution of rounded salt particles;

curing the flexible shell with the rounded salt particles adhered thereto; and

exposing the flexible shell to a solvent for the rounded salt particles for a sufficient amount of time to dissolve the rounded salt particles thereby forming an open-pored structure on the exterior of the flexible shell;

wherein at least one of the physical properties of ultimate break force, ultimate elongation, or ultimate tensile strength of the implant is superior to implants made using the same process and same materials except for angular salt particles instead of rounded salt particles.

14. The breast implant of claim 13, wherein at least two of the physical properties of ultimate break force, ultimate elongation, or ultimate tensile strength of the implant are superior to implants made using the same process and same materials except for angular salt particles instead of rounded salt particles.

15. The breast implant of claim 13, wherein all three of the physical properties of ultimate break force, ultimate elongation, or ultimate tensile strength of the implant are superior to implants made using the same process and same materials except for angular salt particles instead of rounded salt particles.

16. The breast implant of claim 13, wherein the step of forming the flexible shell comprises dipping a mandrel into a liquid dispersion of an elastomeric material.

17. The breast implant of claim 16, wherein the step of forming the flexible shell comprises rotationally molding the shell.

18. The breast implant of claim 16, wherein the rounded salt particles are sodium chloride crystals.

19. The breast implant of claim 16, wherein the rounded salt particles have a maximum particle size range selected from a group of ranges consisting of (1) a range between about 180 microns and about 425 microns, (2) a range between about 425 microns and about 850 microns, and (3) a range between about 850 microns and about 1450 microns.

20. The process of claim 19 wherein about 90% of the rounded salt particles are in the selected particle size range.