US3877080A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acicular silicon carbide dispersion in pyrolytic graphite matrix for use in biomedical implants
Assignee: Atlantic Research Corp
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Filing: 1972-10-30
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Granted: 1975-04-15
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Expires: 1992-10-30
Abstract
Abstract Prosthetic devices for implanting into a living body composed of a composite of a pyrolytic graphite matrix containing codeposited silicon carbide. The pyrolytic graphite matrix comprises crystallite layers of pyrolytic graphite while the silicon carbide is in the form of crystalline aciculae. The silicon carbide aciculae are embedded within the pyrolytic graphite crystallites and oriented so that the longitudinal axes are substantially aligned with the c-direction of the crystallites. The composites of the implant may have a plurality of pores on the surface. These pores can serve as sites for tissue and bone growth, thus improving the attachment of the implant.
Inventors
- 👤 Eugene L Olcott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:27
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/0077; A61F2/02; A61F2/28; A61L; A61L27/00; A61L27/02; A61L27/08; C; C23; C23C; C23C16/00; C23C16/22; A61F2/30; A61F2/3094; A61F2002/30001; A61F2002/30003; A61F2002/3006; A61F2002/30084; A61F2310/00; A61F2310/00005; A61F2310/00161; A61F2310/00173
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
57 words
A BIOMEDICAL IMPLANT COMPOSED OF A COMPOSITE OF PYROLYTIC GRAPHITE AND SILICON CARBIDE IN WHICH SAID PYROLYTIC GRAPHITE COMPRISES LAYERS OF CRYSTLLITES OF PYROLYTIC GRAPHITE AND SAID SILICON CARBIDE COMPRISES CODEPOSITED CRYSTALLINE ACICULAE EMBEDDED IN SAID CRYSTALLITES,SAID ACICULAE BEING ORIENTED SO THAT THE LONGITUDINAL AXES OF THE ACICULAE ARE SUBSTANTIALLY ALIGNED WITH THE C-DIRECTION OF SAID CRYSTALLITES.
Claim 2
Dependent Claim
57 words
A BIOMEDICAL IMPLANT COMPOSED OF A COMPOSITE OF PYROLYTIC GRAPHITE AND SILICON CARBIDE IN WHICH SAID PYROLYTIC GRAPHITE COMPRISES LAYERS OF CRYSTLLITES OF PYROLYTIC GRAPHITE AND SAID SILICON CARBIDE COMPRISES CODEPOSITED CRYSTALLINE ACICULAE EMBEDDED IN SAID CRYSTALLITES,SAID ACICULAE BEING ORIENTED SO THAT THE LONGITUDINAL AXES OF THE ACICULAE ARE SUBSTANTIALLY ALIGNED WITH THE C-DIRECTION OF SAID CRYSTALLITES.
Claim 3
Dependent Claim
17 words
The implant of claim 1 in which said composite has a plurality of pores on its surface.
Claim 4
Dependent Claim
13 words
The implant of clAim 1 in which said composite coats a metallic substrate.
Claim 5
Dependent Claim
13 words
The implant of claim 1 in which said composite coats a carbonaceous substrate.
Claim 6
Dependent Claim
18 words
The implant of claim 1 in which said composite comprises at least 10 percent by volume silicon carbide.
Claim 7
Dependent Claim
20 words
The implant of claim 1 in which said composite comprises between about 5 and 95 percent by volume silicon carbide.
Claim 8
Dependent Claim
18 words
The implant of claim 1 in which said composite comprises about 10 to 50 volume percent silicon carbide.
Claim 9
Dependent Claim
31 words
The implant of claim 1 in which at least 50 percent of the volume of silicon carbide present in said composite comprises aciculae having a length-to-diameter ratio of at least 2:1.
Claim 10
Dependent Claim
31 words
The implant of claim 1 in which at least 50 percent of the volume of silicon carbide present in said composite comprises aciculae having a length-to-diameter ratio of at least 4:1.
Claim 11
Dependent Claim
15 words
The implant of claim 1 which is in the form of an orthopedic prosthetic device.
Claim 12
Dependent Claim
15 words
The implant of claim 2 which is in the form of an orthopedic prosthetic device.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |