Patent US4778471A successfully refreshed from Google Patents.
US4778471A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zcap ceramics
Assignee: University of Dayton
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Filing: 1986-11-19
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Granted: 1988-10-18
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Expires: 2006-11-19
Abstract
Abstract The present invention replaces the aluminum oxide in ALCAP ceramics with zinc oxide or zinc sulfate or mixtures thereof to provide a resorbable high strength ceramic. Specifically, a zinc bioceramic is provided comprising about 10 to 50 wt. % zinc oxide or zinc sulfate or mixtures thereof, about 30 to 40 wt. % calcium oxide and about 10 to 40 wt. % phosphorus pentoxide. The zinc based ceramics of the present invention can be used in many of the same applications as hydroxyapatites, tricalcium phosphates and ALCAP ceramics. When mixed with a setting agent, the zinc based ceramics of the present invention are useful as surgical cements or grouts. The zinc based ceramics are also useful as hard tissue substitutes in orthopedic, dental and maxillofacial surgeries and as drug delivery devices.
Inventors
- 👤 Praphulla K. Bajpai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:01
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/02; A61L27/12; A61L24/00; A61L24/0047; A61L24/0073; A61L24/0084; C; C04; C04B; C04B35/00; C04B35/01; C04B35/447; C04B35/453; A61F; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
47 words
A bioceramic comprising, based on the total weight of said bioceramic, about 10 to 50% by weight zinc oxide or zinc sulfate or mixtures thereof, about 30 to 40% by weight calcium oxide, and about 10 to 40% by weight phosphorus pentoxidel, said bioceramic being aluminum free.
Claim 2
Dependent Claim
47 words
A bioceramic comprising, based on the total weight of said bioceramic, about 10 to 50% by weight zinc oxide or zinc sulfate or mixtures thereof, about 30 to 40% by weight calcium oxide, and about 10 to 40% by weight phosphorus pentoxidel, said bioceramic being aluminum free.
Claim 3
Dependent Claim
17 words
The bioceramic of claim 1 which comprises said zinc oxide, said calcium oxide and said phosphorus pentoxide.
Claim 4
Dependent Claim
18 words
The bioceramic of claim 2 wherein said ceramic has a particle size of about 1 to 400 microns.
Claim 5
Dependent Claim
42 words
The bioceramic of claim 3 wherein said bioceramic comprises, based on the total weight of said bioceramic, about 30 to 50% by weight zinc oxide, about 30 to 40% by weight calcium oxide, and about 20 to 40% by weight phosphorus pentoxide.
Claim 6
Dependent Claim
58 words
A surgical cement composition comprising a powdered bioceramic and a setting agent, said bioceramic comprising, based on the total weight of said bioceramic, about 10 to 50 wt % zinc oxide or zinc sulfate or mixtures thereof, about 30 to 40 wt % calcium oxide, and about 10 to 40 wt % phosphorus pentoxide, said bioceramic being aluminum-free.
Claim 7
Dependent Claim
58 words
A surgical cement composition comprising a powdered bioceramic and a setting agent, said bioceramic comprising, based on the total weight of said bioceramic, about 10 to 50 wt % zinc oxide or zinc sulfate or mixtures thereof, about 30 to 40 wt % calcium oxide, and about 10 to 40 wt % phosphorus pentoxide, said bioceramic being aluminum-free.
Claim 8
Dependent Claim
21 words
The surgical cement composition of claim 5 wherein said bioceramic comprises said zinc oxide, said calcium oxide and said phosphorus pentoxide.
Claim 9
Dependent Claim
32 words
The surgical cement composition of claim 6 wherein said setting agent is selected from the group consisting of amines, amino acids, polyfunctional carboxylic acids, polymers reactive with said bioceramic and mixtures thereof.
Claim 10
Dependent Claim
25 words
The surgical cement composition of claim 7 wherein said amine is selected from the group consisting of carbodiimides; N,N-dimethyl-p-toluidine; N,N-diethyl-p-toluidine; N,N-dimethylaniline; N,N-diethylaniline and mixtures thereof.
Claim 11
Dependent Claim
37 words
The surgical cement composition of claim 7 wherein said amino acid is selected from the group consisting of alanine, arginine, asparagine, cysteine, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, valine and mixtures thereof.
Claim 12
Dependent Claim
35 words
The surgical cement composition of claim 7 wherein said polyfunctional carboxylic acid is selected from the group consisting of aconitic, alpha-ketoglutaric, citraconic, citric, fumaric, glutaconic, itaconic, maleic, malic, pyruvic, oxalic, succinic, tartaric and mixtures thereof.
Claim 13
Dependent Claim
20 words
The surgical cement composition of claim 7 wherein said bioceramic has a particle size of about 1 to 400 microns.
Claim 14
Dependent Claim
15 words
The surgical cement composition of claim 11 wherein said cement further comprises a calcium salt.
Claim 15
Dependent Claim
24 words
The surgical cement composition of claim 7 wherein said polymer is selected from the group consisting of polylactic acid, polyacrylic acid, and polymethacrylic acid.
Claim 16
Dependent Claim
31 words
The surgical cement composition of claim 5 wherein the ratio of said resorbable ceramic to said setting agent based on the weight of said cement composition is about 1:1 to 3:1.
Claim 17
Dependent Claim
54 words
An implant comprising, based on the total weight of said implant, about 10 to 50% by weight zinc oxide or zinc sulfate or mixtures thereof, about 30 to 40% by weight calcium oxide, and about 10 to 40% by weight phosphorus pentoxide, said implant being essentially non-toxic and bioabsorbable, said implant also being aluminum-free.
Claim 18
Dependent Claim
54 words
An implant comprising, based on the total weight of said implant, about 10 to 50% by weight zinc oxide or zinc sulfate or mixtures thereof, about 30 to 40% by weight calcium oxide, and about 10 to 40% by weight phosphorus pentoxide, said implant being essentially non-toxic and bioabsorbable, said implant also being aluminum-free.
Claim 19
Dependent Claim
19 words
The implant of claim 15 wherein said implant comprises said zinc oxide, said calcium oxide and said phosphorus pentoxide.
Claim 20
Dependent Claim
80 words
The implant of claim 16 which is formed by the process comprising the steps of: mixing said oxides and compressing said mixture, calcining said mixture at about 700° to 1300° C. for about 24 to 36 hours, powdering said calcined mixture and sieving said mixture to obtain particles of a size from about 1 to 50 microns, mixing said mixture with a binder and compressing at a pressure of about 2000 to 20,000 pounds total load and sintering said mixture.
Claim 21
Dependent Claim
20 words
The implant of claim 16 wherein after sintering, said implant has a pore size of about 1 to 400 microns.
Claim 22
Dependent Claim
42 words
The implant of claim 18 wherein said implant, based on the total weight of said implant, comprises about 30 to 50% by weight zinc oxide, about 30 to 40% by weight calcium oxide, and about 20 to 40% by weight phosphorus pentoxide.
Claim 23
Dependent Claim
52 words
A bioceramic material comprising, based on the total weight of said bioceramic, of from about 30 to 50% by weight zinc oxide, about 30 to 40% by weight calcium oxide, and from about 20 to 40% by weight phosphorus pentoxide, said bioceramic having a particle size of about 1 to 400 microns.
Claim 24
Dependent Claim
52 words
A bioceramic material comprising, based on the total weight of said bioceramic, of from about 30 to 50% by weight zinc oxide, about 30 to 40% by weight calcium oxide, and from about 20 to 40% by weight phosphorus pentoxide, said bioceramic having a particle size of about 1 to 400 microns.
Claim 25
Dependent Claim
48 words
An implant comprising, based on the total weight of said implant, about 30 to 50% by weight zinc oxide, about 30 to 40% by weight calcium oxide, and about 20 to 40% by weight phosphorus pentoxide, said implant having a pore size of about 1 to 400 microns.
Claim 26
Dependent Claim
48 words
An implant comprising, based on the total weight of said implant, about 30 to 50% by weight zinc oxide, about 30 to 40% by weight calcium oxide, and about 20 to 40% by weight phosphorus pentoxide, said implant having a pore size of about 1 to 400 microns.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1991-10-18 | 1992-04-18 | 1992-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-18 | 1996-04-18 | 1996-10-18 | $3760.00 | Window Closed / Lapsed |
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