US4871312A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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 12:44
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)
DE279144C
Cited
US1307446A
Cited
DE365050C
Cited
US1694857A
Cited
FR775073A
Cited
DE2724516A1
Cited
US4457710A
Cited
US4353698A
Cited
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 |