Biodegradable implant

• US 5,876,452 A
• Filed: 05/30/1995
• Issued: 03/02/1999
• Est. Priority Date: 02/14/1992
• Status: Expired due to Term

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Athanasiou, Kyriacos A., Boyan, Barbara D.
• Primary Examiner(s): ISABELLA, DAVID J
• Application Number:
  US08/452,796
• Time in Patent Office: 1,372 Days
• Field of Search: 623/11, 623/12, 623/16-23, 623/66, 424/423, 424/424, 424/425, 424/426, 514/944, 514/953
• US Class Current: 623/23.72
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2002/0086 for preferentially controlling or promoting the growth of specific types of cells or tissues
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/2839 Bone plugs or bone graft dowels
• CPC Class Codes: A61F 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/30032 differing in absorbability or resorbability, i.e. in absorption or resorption time
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30677 Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/3093 for promoting ingrowth of bone tissue
• CPC Class Codes: A61F 2002/30971 Laminates, i.e. layered products
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0023 differing in porosity
• CPC Class Codes: A61F 2250/003 differing in adsorbability or resorbability, i.e. in adsorption or resorption time
• CPC Class Codes: A61L 31/14 : Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: A61L 31/146 : Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 31/148 : Materials at least partially resorbable by the body

Abstract

Biodegradable, porous, polymeric implant material provides substantially continuous release of bioactive agent during in vivo use. Bioactive agent is initially released in amounts that are less than degradation rate of polymer, thereby promoting migration of cells into material. Later larger amounts of bioactive agent are released, thereby promoting differentiation of cells. Method of making material includes steps of applying vacuum temperature and consession to form pores. Implant material may be adapted for one phase implant (e.g., for bone or cartilage) or for two phase layered implant (e.g., for cartilage layer on top of bone layer).

Claims

1. A porous bioerodible tissue implant device comprising a bioerodible synthetic polymeric material having a uniform non-fibrous composition characterized in that said material has a predetermined uniform porosity and is adapted to be implanted during use into cartilage, said polymeric material having the stiffness and compressibility properties of said cartilage.

3. An implant device of claim 1 having access sites for receiving growth of tissue therein comprising passages extending into the material.

5. An implant device of claim 1 having a growth factor, bioactive agent to induce, promote, or support tissue ingrowth and repair incorporated into said polymeric material.

2. A molded, porous bioerodible tissue implant device comprising a bioerodible polymeric material, said device having a uniform, substantially solid, composition throughout the volume enclosed by the implant, characterized in that said material has a predetermined uniform porosity and is adapted to be implanted during use into bone, said polymeric material having the stiffness and compressibility properties of said bone.

4. An implant device of claim 2 having access sites for receiving growth of tissue therein comprising passages extending into the material.

6. An implant device of claim 2 having a growth factor, bioactive agent to induce, promote, or support tissue ingrowth and repair incorporated into said polymeric material.