Endodontic rotary instruments made from hollow tubes and methods of manufacturing thereof

Patent metadata

Field	Value
Publication number	US-9539063-B2
Application number	US-201213404570-A
Country	US
Kind code	B2
Filing date	Feb 24, 2012
Priority date	Feb 24, 2011
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

A method for manufacturing a hollow instrument comprising the steps of: providing a hollow tube having a longitudinal tube axis; forming at least one opening along a shaft portion of the hollow tube following a predetermined pattern thereby defining a plurality of fingers; and deforming at least a portion of the hollow tube into a desired shape; and optionally joining at least two fingers along a portion of the opening to secure the hollow tube in the desired shape thereby forming the hollow instrument.

First claim

What is claimed:

1. A method for manufacturing a hollow endodontic rotary file useful for shaping and cleaning root canals, comprising the steps of:
a. providing a hollow tube extending along a longitudinal tube axis, the hollow tube having a proximal end and a shaft portion with a tip;
b. forming a plurality of longitudinal tapered openings along the shaft portion of the hollow tube following a predetermined pattern that extend to the tip thereby defining a plurality of tapered fingers, therebetween, each finger having an outer surface and an inner surface extending between longitudinal opposing edges that extend to a tip end at the tip of the hollow tube, the opposing edges tapering towards one another so that each finger is wider towards the direction of the proximal end and narrower towards the tip; and
c. deforming at least a portion of the hollow tube into a desired shape; and
d. sharpening a portion of at least one of the longitudinal opposing edges to provide a cutting edge;
e. joining at least two tapered fingers along a portion of at least one tapered opening to secure the hollow tube in the desired shape thereby forming the hollow endodontic rotary file;
wherein each tip of the plurality of fingers or a portion proximate to each tip of the plurality of tapered fingers are deformed towards one another and converge towards the tube axis so that the shaft portion has a smaller outer diameter near the tip than at other portions of the shaft portion thereby forming a circumferential tapered shaft portion.

2. The method of claim 1 , wherein the plurality of tapered openings are formed along the shaft portion of the hollow tube defining at least three tapered fingers radially spaced from the tube axis.

3. The method of claim 2 , wherein a first longitudinal tapered opening extends between a first finger and a second finger, a second longitudinal tapered opening extends between the second tapered finger and a third tapered finger, and a third longitudinal tapered opening extends between the third tapered finger and the first tapered finger.

4. The method of claim 3 , wherein each of the at least two tapered fingers include an end portion, the end portions being brought into contact during the deforming step to forming a tip of the tapered shaft portion.

5. The method of claim 3 , wherein during the joining step, the first tapered finger is joined to the second tapered finger through a portion of the first longitudinal tapered opening by at least one binding, the second tapered finger is joined to the third tapered finger through a portion of the second longitudinal tapered opening by at least one binding, and the third tapered finger is joined to the first tapered finger through a portion of the third longitudinal tapered opening by at least one binding.

6. The method of claim 4 , wherein each of the at least two tapered fingers are joined to an adjacent tapered finger through at least one of the plurality of longitudinal tapered openings by at least one binding at the tip of the tapered shaft portion.

7. The method of claim 5 , wherein a plurality of bindings join at least two of the first tapered finger, the second tapered finger and the third tapered finger through at least one of the first longitudinal tapered opening, the second longitudinal tapered opening, and the third longitudinal tapered opening.

8. The method of claim 1 , wherein at least one tapered finger includes a plurality of boss portions.

9. The method of claim 1 , further comprising the step of coating or bonding abrasive material to an external surface of the hollow endodontic rotary file useful for shaping and cleaning root canals.

10. A method for manufacturing a hollow endodontic rotary file useful for shaping and cleaning root canals, comprising the steps of:
a. providing a sheet of material;
b. chemically milling the sheet to form a plurality of openings by removing material following a predetermined pattern, the milled sheet having at least two opposing tapered edges;
c. rolling the milled sheet into a desired tubular geometry;
d. sharpening at least a portion of the plurality of openings to provide a cutting edge; and
e. joining a portion of the at least two opposing edges to secure the desired tubular geometry;
wherein prior to or after step b, the at least two opposing edges are sloped towards one another such that upon joining the at least two opposing edges, a tapered hollow endodontic rotary file, instrument is formed having a shaft portion and a tip; and
wherein the tapered hollow endodontic rotary file converges towards the tip such the a first diameter at the tip is smaller than a second diameter along the shaft portion; and
wherein the predetermined pattern includes a variable groove having curves of decreasing amplitude.

11. The method of claim 10 , further comprising the step of cutting the milled sheet to a desired shape.

12. The method of claim 10 , wherein the chemically milling step is accomplished by photochemical machining.

13. The method of claim 10 , wherein the predetermined pattern defines a matrix formed of the plurality of openings that are at least partially bound by channels having an angled exterior surface.

Assignees

• Maxwell Randall
• Shotton Vincent
• Wilkinson Kevin
• Gao Yong
• Dentsply Int Inc

Inventors

• Maxwell Randall
• Shotton Vincent
• Wilkinson Kevin
• Gao Yong

Classifications

• Y10T29/49567

  Dental appliance making · CPC title

• H01J9/025

  of field emission cathodes · CPC title

• A61C5/42 Primary

  Files for root canals; Handgrips or guiding means therefor · CPC title

• A61C5/023 Primary

  Human Necessities · mapped topic