Soft tissue implant with micron-scale surface texture to optimize anchorage

• US 5,011,494 A
• Filed: 04/20/1990
• Issued: 04/30/1991
• Est. Priority Date: 09/16/1988
• Status: Expired due to Term

• Current Assignee: Clemson University
• Original Assignee: Clemson University
• Inventors: von Recum, Andreas F., Campbell, Craig E.
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US07/511,555
• Time in Patent Office: 375 Days
• Field of Search: 623/1, 623/8, 623/11, 623/12, 623/66, 623/2, 623/13, 623/17, 600/36
• US Class Current: 623/23.74
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence

Abstract

A soft tissue implant device such as a catheter, heart valve, or plastic or reconstructive surgical material, to be at least partially embedded in an implantation site in soft organic tissue of a living organism includes a body defining a surface layer extending over the portion of the body contacting the organic tissue. The surface layer defines a three-dimensional pattern with an exterior surface defining a plurality of spaces and a plurality of solid surface portions. The spaces have a mean bridging distance ranging from greater than 1.0 micron to less than 4.0 microns and the solid surfaces portions have mean breadths ranging from 0.10 micron to 2.0 microns. The mean bridging distance is preferably greater than 1.4 microns and less than 1.9 microns. The exterior surface is substantially free of indentations having a bridging distance measuring in a range from between 10.0 microns and 1,000 microns.

Claims

1. A soft tissue implant device to be at least partially embedded at an implantation site in organic tissue of a living organism while promoting anchorage of the device at the implantation site and the growth of collagen at the implantation site, without causing encapsulation of the embedded portion of the device and without causing inflammatory tissue at the implantation site, the device comprising:

(a) a body;

(b) a surface layer secured to said body and extending over a sufficient portion of said body sot hat only said surface layer contacts the organic tissue at the implantation site;

(c) said surface layer defining a plurality of three-dimensional features;

(d) said feature defining an exterior surface for presenting itself to living cells in organic tissue at the implantation site;

(e) said exterior surface defining a plurality of spaces for presenting themselves to living cells adjacent said exterior surface;

(f) each said space having a bridging distance being the minimum distance an adjacent cell must stretch to span diametrically across said space, said bridging distance being measured in a direction parallel to said exterior surface at said space;

(g) said plurality of spaces having a mean bridging distance ranging from greater than 1.0 micron to less than 4.0 microns; and

(h) wherein said surface layer being produced by casting polymers, which are semifluid and cure over time, onto a surface produced on a glass substrate by selective etching of photoresist spincoated onto a chrome plated glass plate and which has been exposed to a light image followed by being etched down to the chrome and followed by the chrome being etched down to the glass substrate.

2. A device as in claim 1, wherein:

said bridging distance falls within the range from 1.4 microns to 1.9 microns.

3. A device as in claim 1, wherein:

substantially all of the individual bridging distance measurements are within the ranges of 0.1 to 10.0 microns and 1,000 microns and greater than 1,000 microns.

4. A device as in claim 3, wherein:

said exterior surface having at least one closed perimeter defining a solid surface portion therewithin.

5. A device as in claim 4, wherein:

(a) said surface layer defines a plurality of projections,

(b) each said solid surface portion defining the exterior surface of one of said plurality of projections, and

(c) each said projection being separated by at least one said space from each adjacent projection.

6. A device as in claim 5, wherein:

(a) each said projection defining a bridging distance relative to each adjacent projection, each said bridging distance being the smallest distance measured in a direction parallel to said exterior surface and separating each said closed perimeter of each said projection from each said closed perimeter of each said adjacent projection;

(b) each said projection having a breadth dimension, said projection breadth dimension being the smallest diametric dimension measured across said solid surface portion of said projection and measured in a direction parallel to said exterior surface; and

(c) said plurality of projections having a mean breadth dimension ranging from 0.10 micron to 2.0 microns.

7. A device as in claim 6, wherein:

(a) said surface layer defines a plurality of recesses, each said space defining an opening to at least one said recess; and

(b) each said projection having a sidewall defining at least a portion of at least one adjacent recess.

8. A device as in claim 5, wherein:

said plurality of spaces are integral with one another and defines a continuum that separates each said projection from each nearest projection.

9. A device as in claim 1, wherein:

said surface layer is integral with said body.

10. A soft tissue implant device to be at least partially embedded at an implantation site in organic tissue of a living organism while promoting anchorage of the device at the implantation site and the growth of collagen at the implantation site, without causing encapsulation of the embedded portion of the device and without causing inflammatory tissue at the implantation site, the device comprising:

(a) a body;

a surface layer secured to said body and extending over a sufficient portion of said body so that only said surface layer contacts the organic tissue at the implantation site;

(c) said surface layer defining a plurality of three-dimensional features;

(d) said features defining an exterior surface for presenting itself to living cells in organic tissue at the implantation site;

(e) said exterior surface defining a plurality of solid surface portions, each said surface portion being bounded in said exterior surface by a closed perimeter;

(f) a plurality of said surface layer features defining, respectively, a plurality of projections, and each said solid surface portion defining the exterior surface of one of said plurality of projections;

(g) a plurality of spaces defined in said exterior surface and separating each said solid surface portion from each adjacent solid surface portion;

(h) a plurality of bridging distances defined between each said closed perimeter of each said exterior surface portion and each closed perimeter of each adjacent surface portion, each said bridging distance being the minimum diametric distance an adjacent cell must stretch to span between the closest point on the perimeter of each exterior surface portion and the perimeter of each adjacent exterior surface portion, each said bridging distance being measured in a direction parallel to said exterior surface at said exterior surface portions at each end of said bridging distance;

(i) said plurality of exterior surface portions having a mean bridging distance ranging from greater than 1.0 micron to less than 4.0 microns;

(j) each said projection having a breadth dimension, said projection breadth dimension being the smallest diametric dimension of said exterior surface portion measured across said solid surface portion and in a direction parallel to said exterior surface;

(k) said plurality of projections having a mean breadth dimension ranging from 0.10 micron to 2.0 microns; and

(l) wherein said surface layer being produced by casting polymers, which are semifluid and cure over time, onto a surface produced on a glass substrate by selective etching of photoresist spincoated onto a chrome plated glass plate and which has been exposed to a light image followed by being etched down to the chrome and followed by the chrome being etched down to the glass substrate.