Patent US7241313B2 successfully refreshed from Google Patents.
US7241313B2
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Surgical implant
Assignee: Stanmore Implants Worldwide Ltd
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Filing: 2002-08-12
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Granted: 2007-07-10
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Expires: 2022-08-12
Abstract
Abstract A surgical implant comprises a core region and a porous surface region extending over at least part of the core region. The surface region has a predetermined pore volume fraction. A method of manufacturing a surgical implant comprises: (i) loading metallic powder having a predetermined particle size distribution around a pre-formed core in a sealable capsule; (ii) reducing pressure within the capsule to a predetermined pressure below atmospheric pressure; (iii) pressurising the capsule with a process gas to a predetermined pressure higher than the predetermined pressure of step (ii); (iv) sealing the capsule; (v) heating the pressurised sealed capsule at an elevated temperature and an elevated pressure for a predetermined time to produce an implant precursor; (vi) cooling the sealed capsule, and; (vii) heating the implant precursor for a predetermined time at an elevated temperature and a predetermined pressure below atmospheric pressure, whereby to generate porosity in the implant precursor.
Inventors
- 👤 Paul Unwin
- 👤 Gordon Blunn
- 👤 Michael Herbert Jacobs
- 👤 Mark Andrew Ashworth
- 👤 Xinhua Wu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:28
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/50; A61L27/56; A61F; A61F2/00; A61F2/02; A61F2/28; A61F2/30; A61F2/44; A61F2/442; A61F2/4455; A61F2/447; A61L27/02; A61L27/04; A61L27/045; A61L27/047; A61L27/06; B; B33; B33Y; B33Y80/00; A61F2/3094; A61F2002/30001; A61F2002/30003; A61F2002/30004; A61F2002/30011; A61F2002/30108; A61F2002/3011; A61F2002/30112; A61F2002/30133; A61F2002/30138; A61F2002/30153; A61F2002/30199; A61F2002/30224; A61F2002/30316; A61F2002/30329; A61F2002/30448; A61F2002/30535; A61F2002/30593; A61F2/30767; A61F2002/30769; A61F2/30771; A61F2002/30772; A61F2002/30777; A61F2002/30784; A61F2002/30785; A61F2002/30795; A61F2002/30807; A61F2002/3081; A61F2002/30968; A61F2002/3097; A61F2002/30978; A61F2220/00; A61F2220/0025; A61F2220/005; A61F2230/00; A61F2230/0002; A61F2230/0004; A61F2230/0015; A61F2230/0017; A61F2230/0019; A61F2230/0063; A61F2230/0069; A61F2250/00; A61F2250/0014; A61F2250/0023; A61F2250/0024; A61F2310/00; A61F2310/00005; A61F2310/00011; A61F2310/00017; A61F2310/00023; A61F2310/00029; A61F2310/00389; A61F2310/00592; A61F2310/00856; A61F2310/0088; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12993
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
154 words
A method of manufacturing a surgical implant comprising a core region and a porous surface region extending over at least a part of said core region, the porous surface region having a predetermined pore volume fraction, the method comprising the steps of: (i) loading metallic powder having a predetermined particle size distribution around a pre-formed core in a sealable capsule, (ii) reducing pressure within said capsule to a predetermined pressure below atmospheric pressure, (iii) pressurising said capsule with a process gas to a predetermined pressure higher than the predetermined pressure of step (ii), (iv) sealing said capsule, (v) heating said pressurised sealed capsule at an elevated temperature and an elevated pressure for a predetermined time to produce an implant precursor, (vi) cooling said sealed capsule, and (vii) heating said implant precursor for a predetermined time at an elevated temperature and a predetermined pressure below atmospheric pressure, whereby to generate porosity in said implant precursor.
Claim 2
Independent Claim
154 words
A method of manufacturing a surgical implant comprising a core region and a porous surface region extending over at least a part of said core region, the porous surface region having a predetermined pore volume fraction, the method comprising the steps of: (i) loading metallic powder having a predetermined particle size distribution around a pre-formed core in a sealable capsule, (ii) reducing pressure within said capsule to a predetermined pressure below atmospheric pressure, (iii) pressurising said capsule with a process gas to a predetermined pressure higher than the predetermined pressure of step (ii), (iv) sealing said capsule, (v) heating said pressurised sealed capsule at an elevated temperature and an elevated pressure for a predetermined time to produce an implant precursor, (vi) cooling said sealed capsule, and (vii) heating said implant precursor for a predetermined time at an elevated temperature and a predetermined pressure below atmospheric pressure, whereby to generate porosity in said implant precursor.
Claim 3
Dependent Claim
29 words
A method as claimed in claim 1 , wherein the powder used in step (i) has a particle size range of from about 50 μm to about 750 μm.
Claim 4
Dependent Claim
23 words
A method as claimed in claim 1 , wherein the predetermined pressure of step (ii) is 10 −3 mbar (0.1 Pa) or less.
Claim 5
Dependent Claim
23 words
A method as claimed in claim 1 , wherein the predetermined pressure of step (vii) is 10 −3 mbar (0.1 Pa) or less.
Claim 6
Dependent Claim
44 words
A method as claimed in claim 1 , wherein the process gas of step (iii) is an unreactive gas, or a reactive gas, or a mixture of reactive and unreactive gases, the unreactive gas serving as a carrier or diluent for the reactive gas.
Claim 7
Dependent Claim
16 words
A method as claimed in claim 5 , wherein nitrogen is used as the reactive gas.
Claim 8
Dependent Claim
18 words
A method as claimed in claim 1 , wherein a nitriding step is carried out after step (vii).
Claim 9
Dependent Claim
27 words
A method as claimed in claim 1 , wherein the pressure of step (iii) is from about 1×10 5 Pa to about 5×10 5 Pa positive pressure.
Claim 10
Dependent Claim
23 words
A method as claimed in claim 1 , wherein the elevated temperature of step (v) is from about 850 to about 1100 C.
Claim 11
Dependent Claim
23 words
A method as claimed in claim 1 , wherein the elevated temperature of step (vii) is from about 900 to about 1300 C.
Claim 12
Dependent Claim
24 words
A method as claimed in claim 1 , wherein the implant precursor is separated from the capsule after step (vi) prior to step (vii).
Claim 13
Dependent Claim
22 words
A method as claimed in claim 1 , wherein the capsule is separated from the precursor implant after step (vii) by machining.
Claim 14
Dependent Claim
33 words
A method as claimed in claim 1 , wherein the metallic powder is partly consolidated prior to encapsulation, preferably by selective laser sintering a mixture of the metallic powder and a polymeric binder.
Claim 15
Dependent Claim
10 words
An implant manufactured by the method of claim 1 .
Claim 16
Dependent Claim
22 words
An implant as claimed in claim 14 , wherein the pore volume fraction within the porous surface region is 20 to 50%.
Claim 17
Dependent Claim
22 words
An implant as claimed in claim 14 , wherein the pores are interconnected and substantially uniformly distributed within the porous surface region.
Claim 18
Dependent Claim
29 words
An implant as claimed in claim 14 , wherein at least some of the pores have a size in the range of from 100 μm to about 750 μm.
Claim 19
Dependent Claim
20 words
An implant as claimed in claim 14 , wherein the porous surface region is at least about 1 mm thick.
Claim 20
Dependent Claim
45 words
An implant as claimed in claim 14 , wherein distinct regions within the porous surface region have a different pore size distribution and/or a different pore volume fraction such that there is a pore size and/or pore volume fraction gradient within the porous surface region.
Claim 21
Dependent Claim
23 words
An implant as claimed in claim 14 , wherein the core region has a density of from 0.7 to 1.0 of theoretical density.
Claim 22
Dependent Claim
41 words
An implant as claimed in claim 14 , wherein the core region and/or the porous surface region are made from titanium, commercial purity [ASTM B 338 GR 2] titanium, stainless steel, titanium-based alloys, Ti—Al—V alloys, Ti—Al—Nb alloys or cobalt-chromium based alloys.
Claim 23
Dependent Claim
28 words
An implant as claimed in claim 21 , wherein the core region and/or the porous surface region are made from Ti-6Al-4V, Ti-6Al-7Nb, Stellite 21 or stainless steel 316L.
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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) | 2010-07-09 | 2011-01-08 | 2011-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2014-07-09 | 2015-01-08 | 2015-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2018-07-09 | 2019-01-08 | 2019-07-10 | $7700.00 | Window Closed / Lapsed |