Enhanced surface implant and method of manufacture

• US 5,964,803 A
• Filed: 04/21/1997
• Issued: 10/12/1999
• Est. Priority Date: 07/27/1993
• Status: Expired due to Term

• Current Assignee: PMT Corporation
• Original Assignee: PMT Corporation
• Inventors: Trinter, Stephen M., Iversen, Alfred Abner
• Primary Examiner(s): SNOW, BRUCE EDWARD
• Application Number:
  US08/840,969
• Time in Patent Office: 904 Days
• Field of Search: 623/8, 623/11, 623/66, 623/12, 623/901
• 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: 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 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/34 Macromolecular materials
• 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: C08L 83/04 Polysiloxanes

Abstract

An implantable body including an outer membrane forming an enclosure for receiving a filler material. The surface of the outer membrane is characterized by a random distribution of peaks separated by valleys. The peaks and valleys are separated by gradual contoured slopes with a smooth transition between the peaks and valleys which are substantially free from indentation. The enhanced surface provides improved anchoring of the implant, yet reduces host reaction. The enhanced surface is formed by depositing a distribution of cured polymeric particles on an uncured tacky surface. This intermediate surface is then cured, followed by application of a layer of uncured elastomeric material. The entire surface is then cured to form the enhanced surface.

Claims

1. An improved implantable device for implantation in humans having an outer membrane comprising:

a) an enhanced, random sculptured, undulating, irregular, substantially smooth outer membrane surface of smoothly transitioned peaks, valleys, slopes and terraces without substantial indentations or interstices for providing device anchoring in the human body with minimal human-implantable device interface encapsulation, capsular contraction, fibrous capsule generation, trauma and infection, wherein said outer membrane surface is comprised of stacked particles being substantially tetrahedral in shape.

2. The improved implantable device of claim 1, wherein the average differential height from the peaks to the outer membrane surface is in a range of 800 μ

m to 2500 μ

m.

3. The improved implantable device of claim 1, wherein the improved implantable device is a tissue expander.

4. The improved implantable device of claim 1, wherein the improved implantable device is a breast implant.

5. The improved implantable device of claim 1, wherein the device is made of silicone rubber.

6. The improved implantable device of claim 1, wherein the tetrahedral shaped particles have an average size of 300 μ

m to 600 μ

m.

7. The improved implantable device of claim 1, wherein the spaces between the peaks are about 600 μ

m.

8. The improved implantable device of claim 7, wherein said stacked particles have an average size of 300 μ

m to 600 μ

m.

9. The improved implantable device of claim 1, wherein said particles are comprised of cryogenically ground material.

10. An improved implantable device for implantation in humans having a outer membrane comprising:

a) an enhanced, random, sculptured, undulating, irregular, substantially smooth outer membrane surface of smoothly transitioned peaks and valleys for providing device anchoring in the human with minimal human-implantable device interface encapsulation, capsular contraction, fibrous capsule generation, trauma and infection, wherein said peaks are comprised of particles being substantially tetrahedral in shape and being spaced about 600 μ

m.

11. The improved implantable device of claim 10, wherein the improved implantable device is a tissue expander.

12. The improved implantable device of claim 10, wherein the average height differential between the peaks and the outer membrane surface is in a range of 800 μ

m to 2500 μ

m.

13. The improved implantable device of claim 10, wherein said stacked particles have an average size of 300 μ

m to 600 μ

m.

14. The improved implantable device of claim 10, wherein said outer membrane surface is comprised of an intermediate textured surface and a top coat surface.

15. The improved implantable device of claim 14, wherein said intermediate textured surface is comprised of a first layer bonded to polymeric particles distributed over the surface of said first layer.

16. The improved implantable device of claim 15, wherein said top coat surface is applied over said polymeric particles and is bonded to said intermediate textured surface.

17. The improved implantable device of claim 10, wherein said peaks are comprised of stacked silicone rubber particles being substantially tetrahedral in shape.

18. An improved implantable body for implantation in humans comprising:

a) a soft, flexible outer membrane forming an enclosure for receiving a filler material; and

b) an enhanced, undulating, random sculptured, irregular, substantially smooth surface of peaks, valleys, slopes and terraces without interstices and substantial indentations disposed over at least a portion of said outer membrane, said undulating surface formed by;

i) providing an elastomeric material suitable for use as an implant, having a tacky surface;

ii) depositing a random distribution of cured polymeric particles which stack on one another on said tacky surface to form an intermediate textured surface, said particles being constructed of silicone and having an average diameter in a range of 300 μ

m to 600 μ

m;

iii) curing said intermediate textured surface;

iv) applying a layer of uncured elastomeric material over said intermediate textured surface; and

v) curing said intermediate textured surface having said applied layer of uncured elastomeric material for forming said undulating textured surface.

19. The implantable body of claim 18, further comprising a filler material contained within said outer membrane.

20. The implantable body of claim 18, wherein said elastomeric material having a tacky surface is uncured silicone rubber dispersed in solvent.

21. The implantable body of claim 18, wherein said enhanced surface is comprised of cryogenically ground silicone particles.

22. The implantable body of claim 18, wherein the particles are substantially tetrahedral in shape.

23. The implantable body of claim 18, wherein the spacing between said cured polymeric particles on said tacky surface is about 600 μ

m.

24. The implantable body of claim 18, wherein the uncured elastomeric material is silicone rubber.

25. The implantable body of claim 18, wherein said step of curing said intermediate textured surface includes heating to a temperature between 130°

F. and 270°

F. for one hour.

26. The implantable body of claim 25, wherein said step of curing said intermediate textured surface having said applied layer of uncured elastomeric material includes heating to a temperature between 130°

F. and 270°

F. for one hour.

27. The improved implantable device of claim 18, wherein the mean peak surface height differential is in a range of 800 μ

m to 2500 μ

m.

28. The improved implantable device of claim 18, wherein said outer membrane surface is comprised of an intermediate textured surface and a top coat surface.

29. The improved implantable device of claim 28, wherein said intermediate textured surface is comprised of a first layer bonded to polymeric particles distributed over the surface of said first layer.

30. The improved implantable device of claim 29, wherein said top coat surface is applied over said polymeric particles and is bonded to said intermediate textured surface.

31. An improved implantable body for implantation in humans comprising:

a) a soft, flexible outer membrane forming an enclosure for receiving a filler material; and

b) an enhanced, undulating, random sculptured, irregular, substantially smooth surface of peaks, valleys, slopes and terraces without interstices and substantial indentations disposed over at least a portion of said outer membrane, said undulating surface formed by;

i) providing an elastomeric material suitable for use as an implant, having a tacky surface;

ii) depositing a random distribution of cured polymeric particles which stack on one another on said tacky surface to form an intermediate textured surface, said particles being constructed of silicone and being substantially tetrahedral in shape;

iii) curing said intermediate textured surface;

iv) applying a layer of uncured elastomeric material over said intermediate textured surface; and

v) curing said intermediate textured surface having said applied layer of uncured elastomeric material for forming said undulating textured surface.

32. An improved implantable device for implantation in humans having an outer membrane comprising:

a) an enhanced, random sculptured, undulating, irregular, substantially smooth outer membrane surface of smoothly transitioned peaks, valleys, slopes and terraces without substantial indentations or interstices for providing device anchoring in the human body with minimal human-implantable device interface encapsulation, capsular contraction, fibrous capsule generation, trauma and infection, wherein said enhanced surface is comprised of stacked particles having an average diameter in a range of 300 μ

m to 600 μ

m and wherein said particles are substantially tetrahedral in shape.