US5527205A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of fabricating an endodontic instrument
Assignee: Dentsply Sirona Inc
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Filing: 1993-06-14
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Granted: 1996-06-18
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Expires: 2013-06-14
Abstract
Abstract A method of fabricating an endodontic instrument by a machining operation is disclosed, and wherein a wire-like rod composed of a titanium alloy is advanced past a rotating grinding wheel at a relatively slow feed rate, with a sufficient depth of cut to remove all of the material on a given surface without over grinding a previously ground surface, and with the grinding wheel rotating at a relatively slow surface speed. The disclosed method is able to efficiently produce endodontic instruments having a high degree of flexibility, high resistance to torsional breakage, and with sharp cutting edges along the working length.
Inventors
- 👤 Derek E. Heath
- 👤 Jerry A. Mooneyhan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:31
CPC Classifications
B; B24; B24B; B24B19/00; B24B19/02; B24B19/04; A; A61; A61C; A61C5/00; A61C5/40; A61C5/42; B24B19/022
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
152 words
A method of fabricating an endodontic instrument which is characterized by high flexibility and high resistance to torsional breakage, comprising the steps of (a) providing a cylindrical rod of metallic material which is composed of at least about 40% titanium and which has a diameter not greater than about 0.07 inches, and (b) axially moving the rod past a rotating grinding wheel at a feed rate of between about 3 and 8 inches per minute, while rotating the rod about its axis, and so that the wheel removes at least about 25% of the diameter of the rod at the point of maximum removal and forms a helical surface on the rod, and including rotating the grinding wheel at a relatively slow surface speed of not more than about 3000 feet per minute, and wherein the rotating grinding wheel has a relatively fine grit size which is greater than about 200 grit.
Claim 2
Independent Claim
152 words
A method of fabricating an endodontic instrument which is characterized by high flexibility and high resistance to torsional breakage, comprising the steps of (a) providing a cylindrical rod of metallic material which is composed of at least about 40% titanium and which has a diameter not greater than about 0.07 inches, and (b) axially moving the rod past a rotating grinding wheel at a feed rate of between about 3 and 8 inches per minute, while rotating the rod about its axis, and so that the wheel removes at least about 25% of the diameter of the rod at the point of maximum removal and forms a helical surface on the rod, and including rotating the grinding wheel at a relatively slow surface speed of not more than about 3000 feet per minute, and wherein the rotating grinding wheel has a relatively fine grit size which is greater than about 200 grit.
Claim 3
Dependent Claim
66 words
The method as defined in claim 1 wherein step (b) includes axially moving the rod at a feed rate of not more than 5 inches per minute, and rotating the grinding wheel at a relatively slow surface speed of not more than about 2200 feet per minute, and wherein the rotating grinding wheel has a relatively fine grit size which is greater than about 220 grit.
Claim 4
Dependent Claim
28 words
The method as defined in claim 1 wherein the cylindrical rod is composed of as alloy comprising at least about 40% titanium and at least about 50% nickel.
Claim 5
Dependent Claim
44 words
The method as defined in claim 1 comprising the further subsequent step of rotatably indexing the rod about a rotational axis of not more than 180 degrees and then repeating step (b) and so as to form a second helical surface on the rod.
Claim 6
Independent Claim
190 words
A method of fabricating an endodontic instrument which is characterized by high flexibility and high resistance to torsional breakage, comprising the steps of (a) providing a cylindrical rod composed of an alloy comprising at least about 40% titanium and at least about 50% nickel, and which has a diameter not greater than about 0.07 inches, (b) axially moving the rod past a rotating grinding wheel at a feed rate of between about 3 and 8 inches per minute, while rotating the rod about its axis, and so that the wheel removes at least about 25% of the diameter of the rod at the point of maximum removal and forms a first helical surface on the rod, and including rotating the grinding wheel at a relatively slow surface speed of not more than about 3000 feet per minute, and wherein the rotating grinding wheel has a relatively fine grit size which is greater than about 200 grit, and then (c) rotatably indexing the rod about a rotational axis of not more than 180 degrees and then repeating step (b) and so as to form a second helical surface on the rod.
Claim 7
Independent Claim
190 words
A method of fabricating an endodontic instrument which is characterized by high flexibility and high resistance to torsional breakage, comprising the steps of (a) providing a cylindrical rod composed of an alloy comprising at least about 40% titanium and at least about 50% nickel, and which has a diameter not greater than about 0.07 inches, (b) axially moving the rod past a rotating grinding wheel at a feed rate of between about 3 and 8 inches per minute, while rotating the rod about its axis, and so that the wheel removes at least about 25% of the diameter of the rod at the point of maximum removal and forms a first helical surface on the rod, and including rotating the grinding wheel at a relatively slow surface speed of not more than about 3000 feet per minute, and wherein the rotating grinding wheel has a relatively fine grit size which is greater than about 200 grit, and then (c) rotatably indexing the rod about a rotational axis of not more than 180 degrees and then repeating step (b) and so as to form a second helical surface on the rod.
Claim 8
Dependent Claim
57 words
The method as defined in claim 5 wherein step (c) includes rotating the rod about a rotational axis of 120 degrees, and comprising the further subsequent step of (d) rotatably indexing the rod about a rotational axis of 120 degrees and then repeating step (b), and so as to form a third helical surface on the rod.
Claim 9
Dependent Claim
43 words
The method as defined in claim 6 wherein the grinding wheel is configured and positioned so that each of said first, second, and third helical surfaces are linear when viewed in transverse cross section, and the finished instrument has a triangular cross section.
Claim 10
Dependent Claim
28 words
The method as defined in claim 5 wherein step (b) further includes axially moving the rod at a feed rate of not more than 5 inches per minute.
Claim 11
Dependent Claim
43 words
The method as defined in claim 5 wherein the rotational axis of the grinding wheel is oriented with respect to the longitudinal axis of the rod so that the wheel lies in a plane which follows the helical configuration of the helical surfaces.
Claim 12
Dependent Claim
27 words
The method as defined in claim 9 wherein said grinding wheel has a curved outer periphery so as to impart a corresponding curvature to the helical surfaces.
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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) | 1999-06-18 | 1999-12-18 | 2000-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-06-18 | 2003-12-18 | 2004-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-06-18 | 2007-12-18 | 2008-06-18 | $7700.00 | Window Closed / Lapsed |