← Back to Patent Explorer
US5250585A Expired / Lapsed US ⏱️ 0.0 years remaining

Dental material in powder form, process for its preparation and use

Assignee: 3M Deutschland GmbH
•
Filing: 1989-07-21
•
Granted: 1993-10-05
•
Expires: 2009-07-21
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A dental material in powder form and being based on (a) aluminum fluorosilicate glass, (b) base metals suitable for dental use, or alloys of these with each other, and optionally (c) dry polycarboxylic acid and/or (d) a chelating agent, which contains at least some of constituent (a) as a sintered mixture with constituent (b).

Inventors

  • 👤 Rainer Guggenberger
  • 👤 Klaus Ellrich
  • 👤 Oswald Gasser
  • 👤 John W. McLean
  • 👤 Owen Makinson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 02:22
CPC Classifications
A; A61; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/884; A61K6/887; A61K6/889

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 55 words
A powder-form dental material based on (a) aluminum-fluorosilicate glass, (b) a tin metal or a tin alloy wherein said tin alloy contains tin and a base metal selected from the group consisting of titanium, tantalum, germanium, niobium, aluminum and zinc which contains at least some of constituent (a) as a sintered mixture with constituent (b).
Claim 2
Dependent Claim 55 words
A powder-form dental material based on (a) aluminum-fluorosilicate glass, (b) a tin metal or a tin alloy wherein said tin alloy contains tin and a base metal selected from the group consisting of titanium, tantalum, germanium, niobium, aluminum and zinc which contains at least some of constituent (a) as a sintered mixture with constituent (b).
Claim 3
Dependent Claim 85 words
A process for the preparation of the powder-form dental material of claim 1 which comprises mixing powders of (a) aluminum-fluorosilicate glass and (b) the tin metal or tin alloy, sintering the mixture obtained at >150° C., optionally after moulding into formed bodies and grinding the sintered product to a powder and optionally one or more of the following steps: mixing the powder obtained with unsintered aluminum fluorosilicate glass, dry polycarboxylic acid and/or a chelating agent, each in powder form, and thermally treating the powder again.
Claim 4
Dependent Claim 14 words
A process according to claim 2, wherein the sintering is carried out under pressure.
Claim 5
Dependent Claim 14 words
A self-hardening glass-ionomer cement which comprises the powder-form dental material according to claim 1.
Claim 6
Dependent Claim 12 words
A self-hardening glass-ionomer cement according to claim 4 which further comprises water.
Claim 7
Dependent Claim 26 words
A powder-form dental material according to claim 1, further comprising at least one component selected from the group consisting of dry polycarboxylic acids and chelating agents.
Claim 8
Dependent Claim 85 words
A process for the preparation of the powder-form dental material of claim 6 which comprises mixing powders of (a) aluminum-fluorosilicate glass and (b) the tin metal or tin alloy, sintering the mixture obtained at >150° C., optionally after moulding into formed bodies, and grinding the sintered product to a powder and optionally one or more of the following steps: mixing the powder obtained with unsintered aluminum fluorosilicate glass, dry polycarboxylic acid and/or a chelating agent, each in powder form, and thermally treating the powder again.
Claim 9
Dependent Claim 14 words
A process according to claim 6, wherein the sintering is carried out under pressure.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-10-04 1997-04-05 1997-10-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-10-04 2001-04-05 2001-10-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-10-04 2005-04-05 2005-10-05 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag