US4902224A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crystalline orthodontic bracket
Assignee: Union Carbide Chemicals and Plastics Technology LLC
•
Filing: 1988-12-19
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Granted: 1990-02-20
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Expires: 2008-12-19
Abstract
Abstract A crystalline orthodontic bracket with enhanced tolerance to fabrication, installation and use is composed of zirconia, yttria, magnesia or strontium titanate.
Inventors
- 👤 Paul R. Collins
- 👤 Larry R. Rothrock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:44
CPC Classifications
A; A61; A61C; A61C7/00; A61C7/12
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
43 words
An orthodontic bracket comprising a body comprising crystalline material having crystalline planes of the group consisting of zirconia, yttria, magnesia and strontium titanate having a base face intended to face a tooth and an opposing front face defining a longitudinal arch wire groove.
Claim 2
Dependent Claim
43 words
An orthodontic bracket comprising a body comprising crystalline material having crystalline planes of the group consisting of zirconia, yttria, magnesia and strontium titanate having a base face intended to face a tooth and an opposing front face defining a longitudinal arch wire groove.
Claim 3
Dependent Claim
15 words
The orthodontic bracket of claim 1 wherein said bracket is made entirely of crystalline zirconia.
Claim 4
Dependent Claim
15 words
The orthodontic bracket of claim 1 wherein said bracket is made entirely of crystalline yttria.
Claim 5
Dependent Claim
38 words
The orthodontic bracket of claim 1 in which the axis of each plane of the crystalline material is at an angle of between about 50° and 70° with respect to the longitudinal axis of the arch wire groove.
Claim 6
Dependent Claim
11 words
The orthodontic bracket of claim 3 wherein said material is zirconia.
Claim 7
Dependent Claim
14 words
The orthodontic bracket of claim 1 having at least one pair of tie wings.
Claim 8
Dependent Claim
23 words
The orthodontic bracket of claim 1 wherein said bracket has a rhomboidal configuration when viewed looking directly at the front of the bracket.
Claim 9
Dependent Claim
23 words
The orthodontic bracket of claim 1 wherein the archwire groove is oriented essentially parallel to the top and bottom faces of the bracket.
Claim 10
Dependent Claim
37 words
The orthodontic bracket of claim 1 in which the crystalline material is cubic and wherein three planes of said cubic crystalline material intersect substantially at an axis parallel to the longitudinal axis of the arch wire groove.
References Cited (Backward Citations)
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US4595598A
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US4639218A
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US4669980A
Cited
US4604097A
Cited
US4604097B1
Cited
US4687441A
Cited
US4789649A
Cited
US4799882A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-19 | 1993-08-21 | 1994-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-19 | 1997-08-21 | 1998-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-19 | 2001-08-21 | 2002-02-20 | $7700.00 | Window Closed / Lapsed |