← Back to Patent Explorer
US5145520A Expired / Lapsed US ⏱️ 0.0 years remaining

Bioactive cement

Assignee: Kyoto University
•
Filing: 1990-08-22
•
Granted: 1992-09-08
•
Expires: 2010-08-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An excellent bioactive cement is provided which can chemically and firmly bond to teeth or bones of living bodies, adapt the shape of defected portions of bones or teeth of living bodies, harden quickly, and exhibit high initial strength, without forming inflammation to the surrounding tissue of living bodies. The bioactive cement is composed of glass powder comprising Ca as a main constituent, and an aqueous solution of ammonium phosphate as a hardening liquid for the glass powder, and is economical and stable without loosing the fixation between the artificial biomaterial and the bones or teeth of living bodies nor degradation thereof in the living bodies during a long period of use in the living bodies.

Inventors

  • 👤 Tadashi Kokubo
  • 👤 Takao Yamamuro
  • 👤 Satoshi Yoshihara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 18:02
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/02; A61L27/12; A61K; A61K6/00; A61K6/15; A61K6/17; A61K6/30; A61K6/70; A61K6/71; A61K6/74; A61K6/75; A61K6/77; A61K6/80; A61K6/849; A61K6/864; A61L24/00; A61L24/02; A61F; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 30 words
A bioactive cement, consisting of glass powder having CaO and SiO 2 as essential constituents; and an aqueous solution of ammonium phosphate as a hardening liquid for the glass powder.
Claim 2
Dependent Claim 30 words
A bioactive cement, consisting of glass powder having CaO and SiO 2 as essential constituents; and an aqueous solution of ammonium phosphate as a hardening liquid for the glass powder.
Claim 3
Dependent Claim 20 words
The bioactive cement as defined in claim 1, wherein the glass powders have diameters of not over than 44 μm.
Claim 4
Dependent Claim 26 words
The bioactive cement as defined in claim 1, wherein the ammonium phosphate is selected from the group consisting of ammonium dihydrogen phosphate and diammonium hydrogen phosphate.
Claim 5
Dependent Claim 43 words
The bioactive cement as defined in claim 1, wherein the ratio of the amount of the hardening liquid to the amount of the glass powder is within a range of 0.35-0.65 mλ of the hardening liquid per 1 g of the glass powder.
Claim 6
Dependent Claim 17 words
The bioactive cement as defined in claim 1, wherein the hardening liquid has a pH of 6.0-8.5.
Claim 7
Dependent Claim 21 words
The bioactive cement as defined in claim 1, wherein the amount of CaO in the glass powder is 20-60 wt %.
Claim 8
Dependent Claim 22 words
The bioactive cement as defined in claim 1, wherein the amount of SiO 2 in the glass powder is 31.0-54.5 wt %.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-09-08 1996-03-09 1996-09-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-09-08 2000-03-09 2000-09-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-09-08 2004-03-09 2004-09-08 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag