EP0277678A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A graft suitable for treatment by reconstructive surgery and having tissue-specific porosity, and a process for making such graft
Assignee: Stichting Science Park Groningen
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Filing: 1988-01-18
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Granted: —
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Expires: 2008-01-18
Abstract
Abstract This invention relates to a graft for use in reconstructive surgery to repair damaged tissue, such as bone tissue, cartilage tissue, vascular tissue or nerve tissue. According to the invention the graft is characterized by a porous matrix of an organic polymeric material having a bi-porous structure, i.e., having at least two different pore structures each having its own pore size and pore size distribution. The matrix is preferably biodegradable and preferably incorporates a fibrous and/or a granular material, preferably also biodegradable, and/or additives, such as growth factors. The invention also relates to a process for making bi-porous grafts.
Inventors
- 👤 Atze Jan Nijenhuis
- 👤 Jan Willem Leenslag
- 👤 Albertus Johannes Pennings
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-22 21:07
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/28; A61F2/30; A61F2/30756; A61F2/04; A61F2/06; A61F2/3094; A61F2/30965; A61F2002/2835; A61F2002/30001; A61F2002/30003; A61F2002/30004; A61F2002/30011; A61F2002/3006; A61F2002/30062; A61F2002/30084; A61F2210/00; A61F2210/0004; A61F2250/00; A61F2250/0014; A61F2250/0023
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
33 words
A graft suitable for the treatment by reconstructive surgery of damaged bone tissue, cartilage tissue, vascular tissue and nerve-tissue, characterized by a porous matrix of an organic polymeric material with a bi-porous structure.
Claim 2
Dependent Claim
33 words
A graft suitable for the treatment by reconstructive surgery of damaged bone tissue, cartilage tissue, vascular tissue and nerve-tissue, characterized by a porous matrix of an organic polymeric material with a bi-porous structure.
Claim 3
Dependent Claim
16 words
A graft as claimed in claim 1, characterized in that the organic polymeric material is biodegradable.
Claim 4
Dependent Claim
42 words
A graft as claimed in claim 1 or 2, characterized in that the matrix incorporates a biodegradable organic polymeric fibrous material in the form of loose fibres and/or in the form of a coherent fibre combination and/or a biodegradable first granular material.
Claim 5
Dependent Claim
51 words
A graft as claimed in any of claims 1-3, characterized in that the matrix material and/or fibre material and/or the first granular material incorporates one or more growth factors or growth promoting agents, and/or that the growth factors and/or growth promoting agents are distributed over the pore walls of the graft.
Claim 6
Dependent Claim
24 words
A graft as claimed in claim 1 or 3, characterized in that one of the components is a very slowly biodegradable or non-biodegradable component.
Claim 7
Dependent Claim
35 words
A graft as claimed in claim 1, characterized in that the bi-porous structure comprises pores having a pore size of 80-300 µm, dispersed in the porous matrix having pores of a size of 5-100 µm.
Claim 8
Dependent Claim
35 words
A graft as claimed in claim 6, characterized in that the bi-porous structure comprises pores having a pore size of 150-250 µm, dispersed in the porous matrix having pores of a size of 10-60 µm.
Claim 9
Dependent Claim
106 words
A process for making a graft as claimed in any of claims 1-7, characterized by subjecting a solidified polymeric solution under reduced pressure to a sublimation process to remove the solvent, the solidified polymeric solution being composed of the polymeric material or mixture of polymeric materials constituting the porous matrix; a sublimable solvent or a mixture of sublimable solvents or a mixture of one or more sublimable solvents and one or more sublimable first non-solvents; and a second granular material different from said first granular material and capable of being washed out with a solvent which is not a solvent for the biodegradable organic polymeric matrix.
Claim 10
Dependent Claim
23 words
A process as claimed in claim 8, characterized in that during the solidification of the polymeric solution crystallization or eutectic crystallization takes place.
Claim 11
Dependent Claim
29 words
A process as claimed in claim 8 which includes the use of a first non-solvent, characterized in that during the solidification of the polymeric solution phase separation takes place.
Claim 12
Dependent Claim
66 words
A process as claimed in claim 8, characterized in that the solidified polymer solution includes as components the biodegradable organic polymeric fibrous material in the form of loose fibres and/or in the form of a coherent fibre combination and/or a biodegradable first granular material, which components are insoluble in the solvent for the second granular material which is a non-solvent for the biodegradable organic polymeric matrix.
Claim 13
Dependent Claim
30 words
A process as claimed in claim 11, characterized in that the second granular material is a ground, powdered or crystalline material having a pre-determinable particle size or particle size distribution.
Claim 14
Dependent Claim
20 words
A process as claimed in claim 12, characterized in that the second granular material is of organic and/or inorganic nature.
Claim 15
Dependent Claim
17 words
A process as claimed in claim 13, characterized in that the second granular material is a sugar.
Claim 16
Dependent Claim
16 words
A process as claimed in claim 13, characterized in that the second granular material is urea.
Claim 17
Dependent Claim
21 words
A process as claimed in claim 13, characterized in that the second granular material is an inorganic salt and/or organic salt.
References Cited (Backward Citations)
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