Patent US4871312A successfully refreshed from Google Patents.
US4871312A
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Dental compactor instrument
Assignee: Dentsply Sirona Inc
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Filing: 1988-11-04
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Granted: 1989-10-03
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Expires: 2008-11-04
Abstract
Abstract A dental instrument adapted to be used as a dental compactor for condensing a thermoplastic material in the extirpated root canal of a tooth. The dental compactor instrument is formed with a tapered shank or working portion having at least two helical flutes defining at least two continuous helical shoulders. A helical peripheral land extends between adjacent helical flutes at the periphery of the shank. The shoulders have a neutral rake angle at the periphery of the shank.
Inventors
- 👤 Derek E. Heath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:42
CPC Classifications
A; A61; A61C; A61C5/00; A61C5/50
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
94 words
A dental compactor instrument comprising: a shank terminating at a pilot tip end; a tapered working portion along at least a portion of the length of said shank; flute means formed in the working portion of the shank defining at least two continuous helical flutes having helical shoulders at the periphery of said working portion of said shank; a helical land at the periphery of the working portion of said shank extending between adjacent flutes; and helical shoulders having a substantially neutral rake angle at the periphery of said working portion of said shank.
Claim 2
Dependent Claim
94 words
A dental compactor instrument comprising: a shank terminating at a pilot tip end; a tapered working portion along at least a portion of the length of said shank; flute means formed in the working portion of the shank defining at least two continuous helical flutes having helical shoulders at the periphery of said working portion of said shank; a helical land at the periphery of the working portion of said shank extending between adjacent flutes; and helical shoulders having a substantially neutral rake angle at the periphery of said working portion of said shank.
Claim 3
Dependent Claim
18 words
The dental compactor instrument of claim 1 wherein the width of the lands is over about 0.004 inches.
Claim 4
Dependent Claim
31 words
The dental compactor instrument of claim 2, wherein the region of the flute walls defining the neutral rake angle lay substantially on a radius of said working portion of said shank.
Claim 5
Dependent Claim
20 words
The dental compactor of claim 2, wherein each of said flutes, in transverse cross-section of said flute, are arcuately concave.
Claim 6
Dependent Claim
14 words
The dental compactor instrument of claim 4 wherein the flutes are of variable depth.
Claim 7
Dependent Claim
17 words
The dental compactor instrument of claim 1, wherein said flutes are of uniform width and uniform pitch.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-02 | 1993-04-03 | 1993-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-02 | 1997-04-03 | 1997-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-02 | 2001-04-03 | 2001-10-03 | $7700.00 | Window Closed / Lapsed |