US4976738A
Expired / Lapsed
US
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Porous metal overlay for an implant surface
Assignee: Sulzer AG
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Filing: 1985-12-02
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Granted: 1990-12-11
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Expires: 2005-12-02
Abstract
Abstract The porous metal overlay for an implant surface is comprised of a plurality of layers of stacked metal grids. Each layer is provided with pores which are of a size which decrease in the direction of the implant surface steadily, that is, without enlargement in an intermediate layer. The progressively decreasing porous sizes provide for a steady ingrowth and nourishment of the ingrowing tissue.
Inventors
- 👤 Otto Frey
- 👤 Manfred Semlitsch
- 👤 Heinz Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:20
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/30767; A61F2/30907; B; B22; B22F; B22F7/00; B22F7/002; A61F2/32; A61F2/36; A61F2/3662; A61F2002/30001; A61F2002/30003; A61F2002/30004; A61F2002/30011; A61F2002/30316; A61F2002/30317; A61F2002/30327; A61F2002/30329; A61F2002/30448; A61F2002/30451; A61F2002/30909; A61F2002/30914; A61F2002/30915; A61F2002/30929; A61F2/3094; A61F2002/30968; A61F2220/00; A61F2220/0025; A61F2220/005; A61F2220/0058; A61F2250/00; A61F2250/0014; A61F2250/0023; A61F2250/0039; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00389; A61F2310/00395; A61F2310/00407; A61F2310/00419; A61F2310/00485; A61F2310/00491; A61F2310/00544
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
67 words
A porous metal overlay for an implant surface comprising a plurality of layers of stacked metal grids having a controlled reduction of pore size from an outer surface to an opposite inner surface, each said layer having a plurality of pores therein with the size of said pores being of decreasing size in a direction form said outer surface of said overlay to said opposite inner surface.
Claim 2
Dependent Claim
67 words
A porous metal overlay for an implant surface comprising a plurality of layers of stacked metal grids having a controlled reduction of pore size from an outer surface to an opposite inner surface, each said layer having a plurality of pores therein with the size of said pores being of decreasing size in a direction form said outer surface of said overlay to said opposite inner surface.
Claim 3
Dependent Claim
24 words
A porous metal overlay as set forth in claim 1 which further comprises a plate secured to said layer at said opposite inner surface.
Claim 4
Dependent Claim
26 words
A porous metal overlay as set forth in claim 1 wherein at least some of said layers are characterized in having been rolled prior to stacking.
Claim 5
Dependent Claim
28 words
A porous metal overlay as set forth in claim 1 wherein each layer has pores and bar widths in a range of from 0.05 millimeters to 1.5 millimeters.
Claim 6
Dependent Claim
22 words
A porous metal overlay as set forth in claim 1 wherein each layer has a pore volume of from 20% to 90%.
Claim 7
Dependent Claim
60 words
A porous structure for a bone implant comprising a plurality of stacked layers of metal grids, each layer having a uniform porosity with a plurality of pores therein, said layers having a controlled reduction of pore size with the pore size of each layer decreasing in size from one surface of the structure to an opposite surface of the structure.
Claim 8
Dependent Claim
60 words
A porous structure for a bone implant comprising a plurality of stacked layers of metal grids, each layer having a uniform porosity with a plurality of pores therein, said layers having a controlled reduction of pore size with the pore size of each layer decreasing in size from one surface of the structure to an opposite surface of the structure.
Claim 9
Dependent Claim
30 words
A porous structure as set forth in claim 6 wherein each layer is formed of a material selected from the group consisting of titanium, tantalum, niobium, zirconium and alloys thereof.
Claim 10
Dependent Claim
27 words
A porous structure as set forth in claim 6 wherein each layer has pores and bar widths in a range of from 0.05 millimeters to 1.5 millimeters.
Claim 11
Dependent Claim
21 words
A porous structure as set forth in claim 6 wherein each layer has a pore volume of from 20% to 90%.
Claim 12
Dependent Claim
19 words
A porous structure as set forth in claim 6 which further comprises a plate secured to said opposite surface.
Claim 13
Dependent Claim
34 words
A porous structure as set forth in claim 10 wherein each said layer and said plate is formed of a material selected from the group consisting of titanium, tantalum, niobium, zirconium and alloys thereof.
Claim 14
Dependent Claim
94 words
In combination an anchoring shank for a prosthesis; and a plurality of layers of metal grids secured to said shank for an accretion of tissue therein, each layer having a plurality of pores therein with the pore size of each layer decreasing in size from a layer remote from said shank to a layer adjacent said shank to provide a controlled reduction of pore size from said remote layer to said layer adjacent said shank whereby ingrowing tissue is able to ramify without interruption by an enlargement of said pores in an intermediate layer.
Claim 15
Dependent Claim
94 words
In combination an anchoring shank for a prosthesis; and a plurality of layers of metal grids secured to said shank for an accretion of tissue therein, each layer having a plurality of pores therein with the pore size of each layer decreasing in size from a layer remote from said shank to a layer adjacent said shank to provide a controlled reduction of pore size from said remote layer to said layer adjacent said shank whereby ingrowing tissue is able to ramify without interruption by an enlargement of said pores in an intermediate layer.
Claim 16
Dependent Claim
25 words
The combination as set forth in claim 12 wherein said pores of said layers are of a size of from 0.05 millimeters to 1.5 millimeters.
Claim 17
Dependent Claim
26 words
The combination as set forth in claim 12 which further comprises a metal plate secured to and between said shank and said layer adjacent said shank.
Claim 18
Dependent Claim
31 words
The combination as set forth in claim 14 wherein said plate and each said layer is formed of a material selected group consisting of titanunim, tantalum, niobium, zirconium and alloys thereof.
Claim 19
Dependent Claim
37 words
The combination as set forth in claim 15 wherein said pores of each layer are of a size of from 0.05 millimeters to 1.5 millimeters and each layer has a pore volume of from 20% to 90%.
Claim 20
Dependent Claim
78 words
The combination as set forth in claim 15 wherein said layers total three and wherein said layer adjacent said shank is made of wires of a diameter of 0.1 millimeters with a mesh clearance of 0.20 millimeters, the middle layer is made of wires of a diameter of 0.25 millimeters with a mesh clearance of 0.50 millimeters and the remote layer is made of wires of a diameter of 0.5 millimeters and a mesh clearance of 1.0 millimeters.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-10 | 1994-06-11 | 1994-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-10 | 1998-06-11 | 1998-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-10 | 2002-06-11 | 2002-12-11 | $7700.00 | Window Closed / Lapsed |