Cutting the end of an endodontic brush

Abstract

To provide an endodontic brush.SOLUTION: A distal end of an endodontic brush that is non-uniform, not along a line perpendicular to the axis of the brush. Optionally, the non-uniform strands contact the walls of the channel more uniformly and / or have an enhanced stirring effect compared to a uniformly cut end which may be cut using an abrasive cutter and / or a laser and / or an electrical discharge machining cutter. Optionally, the grinding wheel rotates counter to the windings of the wire. Optionally, a rounded end can be formed on the wire. In some embodiments, the coupling means between the endodontic brush and the handpiece is configured to be rotationally held to the handpiece by friction and / or longitudinally locked into the handpiece by an interference element. In some embodiments, the edge of the brush is roughened. Optionally, the brush may be bent and / or eccentric.SELECTED DRAWING: Figure 17

Description

[Technical Field]

[0001] (Related Applications) This application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 63 / 108,363, filed November 1, 2020, which is incorporated herein by reference in its entirety.

[0002] This application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 62 / 988,453, filed March 12, 2020, which is incorporated herein by reference in its entirety.

[0003] The present invention, in some embodiments, relates to endodontic brushes, and more particularly, but not exclusively, to improved configurations of the distal end thereof.

[0004] U.S. Patent No. 8,790,116, whose inventor overlaps with the present application, appears to disclose that "an endodontic file (10) has at least a central longitudinal cord (12), a helically wound wire (14) at least partially surrounding the cord, and a resilient grip (16) partially covering the helically wound wire near a first end and having an outer diameter slightly wider than the inner diameter of the barrel of the dental instrument, thereby being supported by friction alone during insertion into the barrel."

[0005] U.S. Patent No. 9,585,731 appears to disclose that "an endodontic file (10) includes a handle (11) and a helical cord (15) of helically wound metal wire wound in a predetermined direction around a central metal cord (13) and formed between opposite ends of the central cord to form a generally conical unitary structure (18) including a narrow distal end (17) and an opposite, wider upper end (16) supported at its upper end by the handle. Flexible conical reinforcements (26, 31) supported by the handle cover the outermost layer of the upper helical cord away from the distal end, the lower end of the helical cord having a diameter small enough to enter the root canal and dimensions at its upper end to limit bending of the upper portion. The outer surface (20) of the helical cord is configured to remove material within the root canal when the endodontic file is rotated in a predetermined direction."

[0006] U.S. Patent No. 8,647,116 appears to disclose that "an endodontic file (10) has at least a central longitudinal cord (12), a helically wound wire (14) at least partially surrounding the cord, and a resilient grip (16) partially covering the helically wound wire near a first end and having an outer diameter slightly wider than the inner diameter of the barrel of the dental instrument such that it is internally supported solely by friction upon insertion into the barrel."

[0007] U.S. Patent Publication No. 20140004479 appears to disclose "an endodontic instrument for drilling a root canal of a tooth. The instrument comprises a working area for forming and / or shaping and / or cutting the walls of the root canal of a tooth. The working area is provided with a support end piece which may be attached to a manually or mechanically driven mount. The working area is configured to adopt a retracted configuration when a predetermined variation in the temperature of the instrument causes the instrument to go from an inoperative position to a working position or vice versa. For this purpose, the working area is made from an alloy wire having shape memory properties or particular elastic properties."

[0008] U.S. Patent No. 9,931,179 appears to disclose "a method for forming a shape-memorized dental instrument or device, the method including: selecting a nitinol wire having a starting transition temperature below room temperature; grinding the nitinol wire to form the dental instrument or device having a shank located adjacent a first end and a working area having at least one cutting edge located adjacent an opposite second tip; shaping the working area into a formed shape having at least one protrusion formed therein; heating the dental instrument or device to a) change the starting transition temperature of the dental instrument or device to a final transition temperature; and b) memorizing the formed shape including the at least one protrusion, whereby the dental instrument or device automatically returns to the formed shape having the at least one protrusion when the dental instrument or device is at a temperature equal to or greater than the final transition temperature."

[0009] Tuan Anh Nguyen, Yaelim Kim, Euiseong Kim, Su-Jung Shin, and Sunil Kim, "Comparison of the Efficacy of Different Techniques for the Removal of Root Canal Filling Material in Artificial Teeth": A Micro-Computed Tomography Study, J.Clin.Med 2019, 8(7), 984; https: / / doi.org / 103390 / jcm8070984 states, "The purpose of the study was to evaluate the effectiveness of three different techniques for removing root canal filling material after filling with gutta percha (GP) cones and calcium silicate-based sealant by measuring the percentage of GP plaque and the amount of sealant remaining in the root canal using micro-computed tomography (micro-CT). Filling material was removed from 30 plastic teeth using a nickel-titanium (Ni-Ti) rotary retreatment system. Final irrigation was performed with 2 mL of saline, and 10 samples were randomly assigned to the conventional group. In the passive ultrasonic irrigation (PUI) group, ultrasonic irrigation was performed. In the Gentle File Brush (GF Brush) group, cleaning with a GF brush was added to the conventional group (n = 10). The remaining filling material was measured using micro-CT imaging diffraction. The total mean volume of remaining filling material after retreatment in the conventional, PUI, and GF Brush groups was 4.84896 mm3, 0.80702 mm3, and 0.05248 mm3, respectively. The percentage of filling material remaining in the root canal was 6.76% in the conventional group, 1.12% in the PUI group, and 0.07% in the GF Brush group. This study appears to disclose that the cleaning effect of the GF Brush system is superior to that of the Ni-Ti retreatment file and PUI systems in the apical region.

[0010] Additional background art includes Francesco Belleucci and Emanuele Ambu, "Root canal shaping with latest generation of expanding instruments," Endodonitcs, December 4, 2017. Summary of the Invention

[0011] According to an aspect of some embodiments of the present invention there is provided an endodontic brush comprising: a coupler for connecting to a handpiece; a central longitudinal flexible core supported at an end of the handpiece by the coupler; and a distal end of said core comprising a plurality of strands wound in a winding direction and unbonded so that in use when the brush is rotated in a direction opposite to the winding direction the strands unwind and open to form a brush, the distal end being unevenly cut.

[0012] According to some embodiments of the present invention, a plurality of strands surrounds an inner central flexible cable.

[0013] According to some embodiments of the present invention, the endodontic brush further comprises a helical wire at least partially surrounding the core and extending toward a tip of the core opposite the handle end, the tip protruding beyond the helical wire at the tip.

[0014] According to some embodiments of the present invention, the surface of the spiral wire is roughened.

[0015] According to some embodiments of the present invention, the distal portion of the helical wire is longitudinally elongated and transversely narrowed.

[0016] According to some embodiments of the present invention, the windings on the distal portion of the helical wire are looser than the intermediate portion.

[0017] According to some embodiments of the present invention, the windings on the distal portion of the helical wire are oriented parallel to the longitudinal flexible core.

[0018] According to some embodiments of the present invention, the middle section of the endodontic brush is curved.

[0019] According to some embodiments of the present invention, the middle section of the endodontic brush is curved.

[0020] According to some embodiments of the present invention, the strands are wound in the opposite direction to the helical wire, so that rotating the brush in the winding direction of the helical wire tightens the helical wire and unwinds the strands.

[0021] According to some embodiments of the present invention, the strands are wound in the same direction as the spiral wire, so that rotating the brush in the winding direction of the spiral wire tightens the strands along with the spiral wire, and rotating the brush in the unwinding direction of the spiral wire unwinds the strands along with the spiral wire.

[0022] According to some embodiments of the present invention, the tip is cut along a line oriented at an angle of 10 to 80 degrees relative to the axis of the core.

[0023] According to some embodiments of the present invention, the tip is cut along a line oriented at an angle of 25 to 75 degrees relative to the axis of the core.

[0024] According to some embodiments of the present invention, the tip is cut off using an abrasive cutter.

[0025] According to some embodiments of the present invention, the tip is cut using a laser cutter.

[0026] According to some embodiments of the present invention, the tip is cut using an electrical discharge machining (EDM) cutter.

[0027] According to some embodiments of the present invention, the tip is cut along a line oriented at an acute angle to the axis of the core.

[0028] According to some embodiments of the present invention, the coupler is configured to longitudinally lock the handpiece, and the rotational connection between the coupler and the handpiece is frictional.

[0029] According to some embodiments of the present invention, the middle portion of the brush comprises a roughened edge.

[0030] According to some embodiments of the present invention, a proximal portion of the flexible core is bent inside the coupler.

[0031] According to some embodiments of the present invention, the middle portion of the brush is roughened.

[0032] According to an aspect of some embodiments of the present invention there is provided a method of manufacturing an endodontic brush, the method including: providing a coupler for connection to a hand piece; winding a plurality of strands to form a flexible core; supporting the flexible core at an end of the hand piece with the coupler, wherein a tip of the core opposite the hand piece end is uncoupled so that in use when the brush is rotated in a direction opposite to the winding direction the strands unwind and open to form the brush; and cutting the tip unevenly.

[0033] According to some embodiments of the present invention, the wrapping surrounds an inner central flexible cable.

[0034] According to some embodiments of the present invention, the method further includes helically winding a wire that at least partially surrounds the core and extends toward a distal end of the core opposite the handle end, with an unbonded portion of the core protruding beyond the helical wire at the distal end.

[0035] According to some embodiments of the present invention, the cutting is along a line oriented at an acute angle relative to the axis of the core.

[0036] According to some embodiments of the present invention, the cutting is along a line oriented at an angle of 10 to 80 degrees relative to the axis of the core.

[0037] According to some embodiments of the present invention, the cutting is along a line oriented at an angle of 25 to 75 degrees relative to the axis of the core.

[0038] According to some embodiments of the present invention, the cutting is by an abrasive cutter.

[0039] According to some embodiments of the present invention, the cutting is by a laser cutter.

[0040] According to some embodiments of the present invention, the cutting is by an electrical discharge machining (EDM) cutter.

[0041] According to an aspect of some embodiments of the present invention there is provided an endodontic brush including: a coupler for connecting to a handpiece; a central longitudinal flexible core supported at an end of the handpiece by the coupler; a distal end of said core including a plurality of strands wound in a winding direction and unbonded so that in use when the brush is rotated in a direction opposite the winding direction the strands unwind and open to form the brush; and a helical wire at least partially surrounding the core and extending towards the distal end of the core opposite the handle end, the distal end protruding beyond the helical wire at the distal end, the helical wire having a roughened surface.

[0042] According to some embodiments of the present invention, the distal portion of the helical wire is longitudinally elongated and transversely narrowed.

[0043] According to some embodiments of the present invention, the windings on the distal portion of the helical wire are looser than the intermediate portion.

[0044] According to some embodiments of the present invention, the windings on the distal portion of the helical wire are oriented parallel to the longitudinal flexible core.

[0045] According to some embodiments of the present invention, the middle section of the endodontic brush is curved.

[0046] According to some embodiments of the present invention, the middle section of the endodontic brush is curved.

[0047] According to some embodiments of the present invention, a proximal portion of the flexible core is bent inside the coupler.

[0048] In accordance with an aspect of some embodiments of the present invention there is provided an endodontic file including: a proximal handle configured to be attached to a dental handpiece and rotate about an axis of rotation, the proximal handle having an average center of mass; and a curved body including a central core and a helical wire wound around the core.

[0049] According to some embodiments of the present invention, the central core comprises a bundle of strands.

[0050] According to some embodiments of the present invention, the distal portion of the core is free, allowing the strands to spread out to form the brush.

[0051] According to some embodiments of the present invention, the width of each strand is in the range of 5 / 100 to 1 / 10 mm.

[0052] According to some embodiments of the present invention, the width of the core is in the range of 1 / 10 to 8 / 10 mm.

[0053] According to some embodiments of the present invention, the width of the spiral wire is in the range of 1 / 10 to 6 / 10 mm.

[0054] According to some embodiments of the present invention, the endodontic file further comprises a distal brush portion.

[0055] According to some embodiments of the present invention, the geometry of the file is eccentric.

[0056] According to some embodiments of the present invention, the geometry of the file is serpentine.

[0057] According to an aspect of some embodiments of the present invention there is provided an endodontic file including: a proximal handle configured to be attached to a dental handpiece and rotated about an axis of rotation, the proximal handle having an average center of mass; a transition section distal to the handle, where the distance between the axis of rotation and the local stress-free center of mass of the file increases in a distal direction; and a distal section distal from the transition section to the tip, where the local stress-free center of mass of the active section is always on the same side of the axis of rotation and the distance between the axis of rotation and the local stress-free center of mass of the distal section is greater than the distance between the center of mass of the handle and the axis of rotation.

[0058] According to some embodiments of the present invention, the coefficient of variation of the distance between the stress-free local centers of mass of the files in the distal portion is less than one-half.

[0059] According to some embodiments of the present invention, the distance between the local stress-free centers of mass of the file at any location on the distal portion is less than twice the distance between the center of mass of the handle and the axis of rotation.

[0060] According to some embodiments of the present invention, the length of the transition section is less than 1 / 5 of the total length of the file.

[0061] According to some embodiments of the present invention, the endodontic file further includes a flexible cleaning rod projecting distally from the handle, the transition section and the distal section being within the flexible cleaning rod.

[0062] According to some embodiments of the present invention, the flexibility of the flexible cleaning rod increases in the distal direction.

[0063] According to some embodiments of the present invention, a flexible cleaning rod includes an inner wire core and a helical wire wound around the inner core.

[0064] According to some embodiments of the present invention, the flexible cleaning rod further comprises an outer helical wrapping wound around the helical wire.

[0065] According to some embodiments of the present invention, the outer spiral wrapping has a roughened surface for cleaning the inside of the endodontic root canal.

[0066] According to an aspect of some embodiments of the present invention there is provided a kit for endodontic cleaning comprising: a sterile eccentric endodontic file including a proximal handle configured to be attached to a dental handpiece and rotate about an axis of rotation, the proximal handle having an average center of mass; and a flexible cleaning rod having a distal active part configured to be rotated inside an endodontic root canal to clean the interior of the root canal, the flexible cleaning rod being distal to the handle, the distance between the axis of rotation and the stress-free local center of mass of the distal active part being greater than one-half the radius of the handle; and sterile packaging to maintain the sterility of the sterile eccentric endodontic file.

[0067] According to some embodiments of the present invention, the distance between the axis of rotation and the local unstressed center of mass of the distal active part is greater than the radius of the handle.

[0068] According to some embodiments of the present invention, a flexible cleaning rod includes an inner wire core and a helical wire wound around the inner core.

[0069] According to some embodiments of the present invention, the flexible cleaning rod further comprises an outer helical wrapping wound around the helical wire.

[0070] According to some embodiments of the present invention, the outer spiral wrapping has a roughened surface for cleaning the inside of the root canal.

[0071] According to some embodiments of the present invention, the handle has an average center of mass, and the sterile eccentric endodontic file further includes a transition portion distal to the handle and proximal to the active portion, wherein the distance between the rotation axis and the local stress-free center of mass of the file increases in the distal direction, the active portion extends from the transition portion to the distal tip, the local stress-free center of mass of the active portion is always on the same side of the rotation axis, and the distance between the rotation axis and the local stress-free center of mass of the active portion is greater than the distance between the center of mass of the handle and the rotation axis.

[0072] According to an aspect of some embodiments of the present invention there is provided a method for manufacturing an endodontic file, the method including: providing a sterile eccentric endodontic file including: a proximal handle configured for attachment to a dental handpiece and for rotation about an axis of rotation, the proximal handle having an average center of mass; and a flexible cleaning rod having a distal active part configured for rotation within an endodontic root canal to clean the interior of the root canal, the flexible cleaning rod being distal to the handle, wherein a distance between the axis of rotation and a stress-free local center of mass of the distal active part is greater than a radius of the handle; sterilizing the sterile eccentric endodontic file; and packaging the endodontic file in a sterile-maintaining package in a sterile condition.

[0073] According to some embodiments of the present invention, the distance between the axis of rotation and the local unstressed center of mass of the distal active part is greater than the radius of the handle.

[0074] According to some embodiments of the present invention, a flexible cleaning rod includes an inner wire core and a helical wire wound around the inner core.

[0075] According to some embodiments of the present invention, the flexible cleaning rod further comprises an outer helical wrapping wound around the helical wire.

[0076] According to some embodiments of the present invention, the outer spiral wrapping has a roughened surface for cleaning the inside of the root canal.

[0077] According to an aspect of some embodiments of the present invention there is provided a method of cleaning an endodontic root canal comprising connecting an eccentric flexible endodontic file to a dental handpiece and rotating the file to generate a distal flare of the file.

[0078] According to an aspect of some embodiments of the present invention, there is provided a method of cleaning an endodontic root canal, the method including connecting a proximal handle of an eccentric flexible endodontic file to a dental handpiece and rotating the proximal handle of the file to spread a distal portion of the file in a whipping motion.

[0079] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of this invention, exemplary methods and materials are described below. In the case of conflict, the patent specification, including definitions, will control. Additionally, the materials, methods, and examples are merely illustrative and are not intended to be necessarily limiting. [Brief explanation of the drawings]

[0080] Some embodiments of the present invention are described herein, by way of example only, with reference to the accompanying drawings. Referring now in detail to the drawings, it is emphasized that the details shown are by way of example only and are for the purpose of illustrating embodiments of the invention. In this regard, the description with reference to the drawings will make apparent to those skilled in the art how embodiments of the invention may be practiced.

[0081] In the drawings, [Figure 1A-1B] FIG. 1A is a diagram showing the unevenly cut distal end of an endodontic brush having a closed structure according to one embodiment of the present invention, and FIG. 1B is a diagram showing the unevenly cut distal end of an endodontic brush having a partially open structure according to one embodiment of the present invention. [Figure 1C]FIG. 1 illustrates a diagonally cut strand according to one embodiment of the present invention. [Figure 2] FIG. 10 illustrates a cut at the distal end of an endodontic brush, according to one embodiment of the present invention. [Figure 3A] 10A-10C show an embodiment of an endodontic brush cut with shear clippers. [Figure 3B] 10A-10C show an embodiment of an endodontic brush cut with shear clippers. [Figure 3C] FIG. 10 shows a portion of an endodontic brush cut by an abrasive cutter, according to one embodiment of the present invention. [Figure 3D] FIG. 10 shows a portion of an endodontic brush cut by an abrasive cutter, according to one embodiment of the present invention. [Figure 4] 10 is an image showing a channel being cleaned with a brush, according to one embodiment of the present invention. [Figure 5] 1 is an image of an exemplary experiment showing the effect of centrifugal force. [Figure 6A-7] 6A-6D show cross-sections of exemplary cleaned channels according to one embodiment of the present invention, and FIG. 7 shows a 500x magnified surface 740 of the apex of a channel in a tooth cleaned using an endodontic brush according to one embodiment of the present invention. [Figure 8] 1 is a flowchart of a method for cutting the distal end of an endodontic brush according to one embodiment of the present invention. [Figure 9] 10 is a flowchart illustrating cleaning of an endodontic channel according to one embodiment of the present invention. [Figure 10] 1A-1C illustrate an endodontic instrument (e.g., brush and / or file) assembly according to one embodiment of the present invention. [Figure 11A] 1 shows an endodontic instrument according to one embodiment of this embodiment. [Figure 11B] 1 shows an endodontic instrument according to one embodiment of this embodiment. [Figure 12] 1 is a schematic diagram of an endodontic brush, according to one embodiment of the present invention. [Figure 13]1 is a schematic diagram of an endodontic brush having an extended end, according to one embodiment of the present invention. [Figure 14] FIG. 1 is a schematic diagram of an eccentric endodontic brush, according to one embodiment of the present invention. [Figure 15] FIG. 1 is a schematic diagram of an eccentric endodontic brush, according to one embodiment of the present invention. [Figure 16] FIG. 10 illustrates an endodontic brush in a simulated channel according to one embodiment of the present invention. [Figure 17] FIG. 1 shows an endodontic brush with roughened edges, according to one embodiment of the present invention. [Figure 18] FIG. 1 is a block diagram of an eccentric endodontic file, according to one embodiment of the present invention. [Figure 19] 1 is a flow chart illustrating endodontic root canal cleaning according to one embodiment of the present invention. [Figure 20] FIG. 1 is a block diagram of a kit including an eccentric endodontic file according to one embodiment of the present invention. [Figure 21] 1 is a flowchart illustrating the creation of a kit including an eccentric endodontic file according to one embodiment of the present invention. [Figure 22] FIG. 1 is a schematic diagram of an eccentric endodontic file, according to one embodiment of the present invention. [Figure 23] FIG. 10 is a schematic diagram of a local mean center of gravity of an eccentric endodontic file, according to one embodiment of the present invention. [Figure 24] FIG. 10 is a schematic diagram of a whipping motion of an eccentric endodontic file, according to one embodiment of the present invention. [Figure 25A] FIG. 1 is a schematic diagram of an eccentric endodontic file shallowly inserted into a root canal, according to an embodiment of the present invention. [Figure 25B] FIG. 1 is a schematic diagram of an eccentric endodontic file inserted deep into a root canal, according to an embodiment of the present invention. [Figure 26A] 1 is a low magnification image of an eccentric endodontic file according to one embodiment of the present invention. [Figure 26B] 1 is a medium magnification image of an eccentric endodontic file according to one embodiment of the present invention. [Figure 26C]1 is a high magnification image of an eccentric endodontic file according to one embodiment of the present invention. [Figure 27A] 1 is a highly enlarged schematic view of a longitudinal section of a three-layer eccentric endodontic file according to one embodiment of the present invention. FIG. [Figure 27B] 1 is a highly enlarged schematic view of a longitudinal section of a two-layer eccentric endodontic file according to one embodiment of the present invention. FIG. [Figure 28A] FIG. 2 is a schematic diagram of a corrugated file with brush ends, according to one embodiment of the present invention. [Figure 28B] 1 is a schematic diagram of a corrugated file having a closed tip, according to one embodiment of the present invention. [Figure 29] FIG. 2 is a block diagram of a curved file according to one embodiment of the present invention. [Figure 30] 1 is a flowchart illustrating a method for cleaning a root canal, according to one embodiment of the present invention. [Figure 31] 1 is a flow chart illustrating a two-stage method of root canal cleaning, according to one embodiment of the present invention. [Figure 32] 1 is a flow chart illustrating a method for cleaning a channel, according to one embodiment of the present invention. [Figure 33] 1 is a flowchart illustrating a method for cleaning a channel, according to one embodiment of the present invention. [Figure 34] 1 is a flowchart illustrating a method for manufacturing an endodontic brush and / or file, according to one embodiment of the present invention. [Figure 35] 1 is a flowchart illustrating a method for manufacturing an endodontic brush and / or file, according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0082] The present invention, in some embodiments, relates to endodontic brushes, and more particularly, but not exclusively, to improved configurations of the distal end thereof.

[0083] Some embodiments of the present invention are described herein, by way of example only, with reference to the accompanying drawings. Referring now in detail to the drawings, it is emphasized that the details shown are by way of example only and are for the purpose of illustrating embodiments of the invention. In this regard, the description with reference to the drawings will make apparent to those skilled in the art how embodiments of the invention may be practiced.

[0084] overview An aspect of some embodiments of the present invention relates to cutting the distal end of an endodontic brush unevenly (e.g., not along a line perpendicular to the brush axis). Optionally, when the brush strands are spread apart, each strand contacts the channel wall at a different location than the other strands. Optionally, when the brush strands are not spread apart, e.g., when used in a narrow channel, the uneven ends of the brush improve fluid agitation within the channel compared to uniformly cut ends. Separating the locations at which the various brush strands contact the channel wall can prevent grooving and / or fluting of the channel wall. Separating the locations at which the various brush strands contact the channel wall can facilitate uniform cleaning of the channel wall. For example, the distal end of the brush can be cut at an acute angle relative to the brush axis. For example, the angle between the cut end and the axis can preferably be within a range of 30-45 degrees and / or 45-75 degrees, and / or within a range of 5-30 degrees and / or 75-85 degrees.

[0085] One aspect of some embodiments of the present invention relates to cutting the distal end of an endodontic brush. For example, the end can be cut using an abrasive cutter (e.g., a grinding wheel) and / or a laser and / or an electrical discharge machining (EDM) cutter. Conventional wire brushes are cut using scissors-type cutters. Such cutting techniques can leave uneven cuts in the different strands and / or bend the end of the wire, preventing proper opening of the brush. In some embodiments, the grinding wheel rotates in the opposite direction to the windings of the wire, for example, to prevent the cable from unraveling during cutting. Optionally, a rounded end can be formed on the wire, for example, by heating the end of the wire.

[0086] One aspect of some embodiments of the present invention relates to a coupling between an endodontic brush and a handpiece configured to be held relative to the handpiece with greater resistance to longitudinal slippage than rotational slippage. For example, the coupling can be rotatably connected to the handpiece by friction and / or longitudinally locked to the handpiece by an interference element. For example, if the torque between the coupling and the handpiece becomes too high, the coupling can slip relative to the handpiece (e.g., thereby protecting the brush and / or teeth from high torque). Additionally and / or alternatively, the coupling can be longitudinally locked to the handpiece to prevent separation from the handpiece.

[0087] One aspect of some embodiments of the present invention relates to an endodontic brush and / or file having a helical outer coil that unwinds near its distal end. In some embodiments, the proximal portion of the endodontic brush can include an inner core (e.g., the core can include a cable including 1-5 and / or 5-10 and / or 10-20 strands, e.g., each strand having a diameter of 0.02-0.15 mm and the core diameter can be in the range of 0.05-0.30 mm) and / or an outer coil helically wound around the core (e.g., the cord of the outer coil can be wire and / or have a diameter in the range of 0.1-0.4 mm). For example, the diameter of the brush / file at the proximal portion can be twice the diameter of the coil cord plus the diameter of the cable. Optionally, at the distal end, the core can be exposed (e.g., the cable can open into the brush). For example, in the distal region, the diameter of the brush / file can be the diameter of the core. In some embodiments, there may be a region of the brush / file where the coil cord is unwound (e.g., between the proximal portion of the brush / file and the exposed portion of the core). For example, the distal end of the coil cord may be generally straight and / or parallel to the core and / or longitudinally oriented. For example, if the cord and / or coil extend parallel to one another, the width of the brush / file may be equal to the sum of the diameter of the core and the diameter of the coil cord. Optionally, the distal end of the cord may be elongated and / or tapered.

[0088] An aspect of some embodiments of the present invention relates to an endodontic instrument that includes a brush on a distal end and / or a file on a proximal portion. In some embodiments, the proximal portion of the endodontic brush can include an inner core (e.g., the core can include a cable including 1-5, and / or 5-10, and / or 10-20 strands, e.g., each strand having a diameter of 0.02-0.15 mm and the core having a diameter of 0.05-0.30 mm) and / or an outer coil helically wrapped around the cable (e.g., the cord of the outer coil can be wire and / or have a diameter of 0.1-0.4 mm). Optionally, the outer coil can include a roughened surface. For example, the roughened surface can be configured to brush the proximal portion of the endodontic channel. Optionally, the brush can include a distal portion where the core is exposed. For example, the distal portion can have a length of 1-3 mm, and / or 3-9 mm, and / or 9-12 mm. Optionally, the distal end of the instrument can be configured to open as a brush. Optionally, the file and / or brush can be configured to whip back and forth as it pivots. For example, the proximal portion of the instrument can be mounted eccentrically within a rotating handle and / or at an angle to the axis of rotation of the handle. Alternatively or additionally, the instrument (file and / or brush) can be curved and / or corrugated. Optionally, the brush and / or file is flexible. For example, the centrifugal force of the pivoting instrument can cause the file and / or brush to bend outward. The outward movement can cause the file / brush to contact and / or scrape and / or clean the sides of the endodontic channel.

[0089] An aspect of some embodiments of the present invention relates to an endodontic file having an active distal portion that is eccentrically positioned relative to an attached handle for a rotation source. In some embodiments, the file is configured such that pivoting of the handle causes a whipping motion of the distal portion of the file. Optionally, the whipping motion causes the active portion of the file to more thoroughly and / or more uniformly clean surfaces within the root canal. In some embodiments, the file is packaged and / or supplied to the dentist in a sterile package. Optionally, the active portion of the file is highly flexible. For example, the active portion may include one or more helical wires wound around a central cable. In some embodiments, the active portion of the file becomes more flexible as it moves distally along its length. Optionally, the file includes a handle for a dental handpiece at its proximal end. Distal to the adapter is an optional transition region where local eccentricity increases as one moves distally. Optionally, in an unstressed state, all of the active portions of the file distal to the transition region are on one side of the axis of rotation of the handle. For example, in the resting state, the center of mass of the active portion and / or active portion distal to the transition portion may be displaced from the axis of rotation of the handle. For example, in the resting state, the center of mass of the active portion and / or active portion distal to the transition portion may be displaced from the axis of rotation of the handle by more than the radius of the handle. For example, in the resting state, the average center of mass of the active portion and / or active portion distal to the transition portion may be displaced from the axis of rotation of the handle by more than the radius of the handle.

[0090] Various embodiments of the present invention can include straight, concentric, eccentric, bent, and / or wavy open (e.g., brush) and / or closed (e.g., fly) ends. The core windings can be twisted in the same direction and / or opposite direction as the outer windings. The outer windings can be rough and / or smooth. The distal end of the device can be cut perpendicular to the axis and / or at an acute angle.

[0091] Specific Embodiments Before describing at least one embodiment of the present invention in detail, it is to be understood that the invention is not necessarily limited in its application to the details of construction and the arrangement of components and / or methods set forth in the following description and / or illustrated in the drawings and / or examples. The invention is capable of other embodiments or of being practiced or carried out in various ways.

[0092] FIG. 1A shows an unevenly cut distal end of an endodontic brush with a closed structure, according to one embodiment of the present invention. In some embodiments, the endodontic instrument can be configured to clean both the apical and proximal portions of the root canal. For example, the distal end of the instrument can be formed as a brush. The brush can clean the apical portion of the root canal. Optionally, the middle and / or proximal portions can include windings 108. Optionally, the surface of the windings 108 can be roughened and / or the windings can be flexible. For example, the windings 108 can clean the sides of the middle and / or proximal portions of the root canal. Optionally, the instrument can be straight. Alternatively or additionally, the instrument can be eccentric and / or curved. In some embodiments, the windings 108 can be sharpened, for example, toward the distal end. Optionally, the strands of the central core can be twisted in the same direction as the windings. Alternatively or additionally, the strands of the central core may be twisted in the opposite direction to the windings.

[0093] 1B shows an unevenly cut distal end of an endodontic brush with a partially open configuration, according to one embodiment of the present invention. In some embodiments, the distal end of the brush includes an unattached tip 102 of the cable. Optionally, the distal end 104 of the brush is cut at an angle relative to the axis of the brush (e.g., the axis of the brush's connecting means and / or brush core 106). In some embodiments, when the brush opens in the channel, the uneven cutting of the cable strands increases the area where the cable contacts the channel walls. In some embodiments, when the brush opens in the channel, the uneven cutting of the cable strands reduces the likelihood of the brush cutting grooves into the channel walls.

[0094] 1C illustrates a diagonally cut strand according to one embodiment of the present invention, where diagonally cutting the core strands and / or windings can have a sharpening effect on the strands. For example, when a cylindrical strand 131 with a circular cross section is cut diagonally, the cut surface 133 can have an elliptical perimeter 135. The apex 137 of the ellipse is sharper than the perimeter of the circular surface that results from a cut perpendicular to the axis of the cylinder.

[0095] In some embodiments, the endodontic brush is used with a rotary handpiece, e.g., capable of rotating at speeds ranging from 4,000 to 40,000 rpm. Optionally (e.g., as shown in FIG. 7 ), the brush assembly includes a coupler element for coupling to the handpiece and / or central longitudinal core 106, secured at a first end within the coupler element. Optionally, during use, the coupler is secured within the handpiece, and for this purpose is referred to as the “handpiece end” throughout the following description and claims. In some embodiments, the helical winding (e.g., helically wound wire 108) partially surrounds the core and is wound in a first direction (e.g., clockwise) so that as the brush rotates clockwise, the helical wire tends to tighten. In some embodiments, the winding prevents the helical wire from uncoupling upon insertion of the brush into the root canal, thereby preventing the helical wire from catching on the inner wall. The helical wire optionally extends toward a second end of the cord opposite the handle end and protrudes beyond the helical wire 108, which second end is referred to as the distal end and / or "tip" throughout the following description and claims. The tip of the core 106 is optionally unattached on both sides; for example, the protrusions can protrude 2-9 mm from the helical wire and / or can be unattached in the distal 2-9 mm near the tip. In some embodiments, the brush can be inserted into the root canal without rotation and / or while being rotated in an unwinding direction.

[0096] The central cable (e.g., core 106) typically comprises a central single cord and / or several strands (e.g., 4-20) that form a flexible cable. Optionally, the cable is twisted and / or wound. In some embodiments, core 106 can include an inner cable around which the strands are optionally wound. Optionally, the inner cable can include filaments. For example, the filaments can be twisted in the opposite direction to the windings of the strands. Alternatively or additionally, the filaments can be twisted in the same direction as the windings of the strands. Optionally, the core strands and / or filaments comprise stainless steel fibers and / or have a cross-sectional width of approximately 0.03-0.10 mm. The surrounding helically wound wire is optionally made of stainless steel and / or has a cross-sectional width of 0.2-0.4 mm. In one embodiment, the strands are wound in the opposite direction to the helical wire 108. Alternatively or additionally, the strands are wound in the opposite direction to the helical wire 108. Alternatively or additionally, the strands are not wound. The diameter of core 106 is typically, for example, in the range of 0.15-0.35 mm. Optionally, if the strands are wound around the inner cable, 30-70% of the diameter of core 106 is the inner cable, and / or 30-70% of the diameter of core 106 is the outer strands. Optionally, the distal end of the core is thin, reaching deep within the root canal, for example, to the apical constriction and / or the last millimeter.

[0097] In some embodiments, during operation, the coupler is attached to a dental handpiece and / or the distal end is inserted into a root canal of a tooth. While the handpiece is set to rotate, a manual back-and-forth motion is optionally provided; for example, the rotation speed can be within the range of 2000-6000 rpm and / or 6,000-30,000 rpm. Centrifugal force can cause a portion of the helical wire 108 to impact the inner dentin layer of the root canal wall along the root canal's natural curvature and / or complex cross-section. The optional abrasive layer polishes and / or grinds the dentin layer. The optional back-and-forth motion allows for the introduction of an antifriction agent and / or plaque rinse along with the constant flow of irrigation water provided by the handpiece.

[0098] In some embodiments, after the tip 104 of the core 106 reaches the desired location (e.g., the apical constriction of the channel), the assembly is rotated in the opposite direction and / or the brush is withdrawn from the root canal. Optionally, this has the effect of unwinding the twisted core strands to form a brush as shown that provides highly effective plaque removal.

[0099] In some embodiments, the distal end of the tip is cut unevenly to increase the contact area between the strands of the core 106 and the channel wall. For example, as the brush opens, the shorter strands contact the wall at a different location than the longer strands 110. This may facilitate contacting a larger area of ​​the channel wall compared to, for example, strands cut evenly perpendicular to the brush axis. For example, this may result in better cleaning when the brush is moved slowly along the channel and / or when the brush remains stationary longitudinally relative to the channel.

[0100] In some embodiments, cutting the brush unevenly (e.g., different individual strands of the brush have different lengths) can reduce the likelihood of scratching the channel wall. For example, when multiple strands all have the same size, the multiple strands may scratch the same area of ​​the wall. If the brush is not moving longitudinally along the root canal quickly enough, this scraping of the multiple strands may scratch grooves in the wall of the core channel. Optionally, when the brush is cut unevenly and / or the strands have different lengths, each strand scrapes a different area of ​​the wall, reducing the likelihood that some parts of the wall will be repeatedly and / or more heavily scraped than other areas of the wall. For example, this can prevent and / or reduce the likelihood of grooves and / or deep scratches forming in the channel wall (e.g., when the brush continues to rotate without longitudinal movement, e.g., when the user does not work according to a backward and / or forward / backward movement protocol, and / or when the longitudinal movement is paused).

[0101] In some embodiments, for example, when there is a structure to be removed (e.g., a protrusion in the root canal wall and / or a particular blockage where concentrated scratching may facilitate removal), a uniformly cut brush (with the distal ends of the strands cut uniformly perpendicular to the axis) can be used as a special instrument.

[0102] In some embodiments, the disinfecting and / or evacuation action is performed using centrifugal force of the brush on the disinfecting fluid. For example, the centrifugal force can be generated as a result of high-speed rotation of the brush (e.g., 1000-1500 rpm, and / or 1500-8000 rpm, and / or 8000-20000 rpm, and / or 20000-50000 rpm, and / or 50000-150000 rpm). Optionally, the rotation is in the opposite direction to the winding of the strands in the core and / or tip of the brush. For example, this rotation can open the brush and / or expose the fluid to the swirling strands of the brush. In very narrow channels, the brush may not have enough space to fully open. In such cases, uneven cutting of the distal end 104 of the brush can increase turbulence and / or mixing effects (e.g., because individual fibers are differentially exposed to the fluid, even in a closed structure).

[0103] In some embodiments, the brush is opened and / or activated only after injection of disinfectant into the open root canal and / or only after insertion of fluid into the root canal, for example, this can prevent damage to the channel and splashing of fluid out of the channel.

[0104] In some embodiments, uneven cutting of the brush's distal end 104 can facilitate penetration of the brush into narrow portions of the channel (e.g., apical constrictions). For example, if the brush is cut at an angle, the width of the distal end of the tip can be smaller than the overall diameter of the core 106. For example, at its most distal point, the brush can consist of one or a few relatively long final strands 110. These strands can enter extremely narrow constrictions, for example, even narrower than the brush's core 106.

[0105] FIG. 2 illustrates cutting the distal end of an endodontic brush according to one embodiment of the present invention. In some embodiments, the wire at the distal end of the endodontic brush 206 is cut using an abrasive cutter (e.g., a rotating abrasive disk 212). Applicant has observed that conventional cut-off cutters (e.g., shear cutters and / or wedge-shaped cutters [e.g., diagonal cutters]) and / or guillotine cutters may not produce a clean cut. Such cutters (e.g., for small strands of wire, such as those having a diameter of 0.02-0.15 mm) may cause the ends of the cut strands to wrinkle and / or cause the strands to stick together. In some cases, cutting such strands with an abrasive cutter can reduce wrinkles and / or tangles in the strands compared to cutting. Alternatively or additionally, the strands can be cut using a laser cutter and / or an electrical discharge machining (EDM) cutter.

[0106] In some embodiments, the shaft and / or distal end of the brush 206 is held within a clamp 214. For example, the clamp 214 may include a groove into which the shaft of the endodontic brush 206 rests and / or a clamping mechanism (e.g., a grooved block that clamps against a smooth block). In some embodiments, a guide 216 is used to control cutting and / or movement. For example, the cutter can move along the guide 216 while the endodontic brush is stationary, and / or the cutter can move along the guide while the brush 206 is stationary. Optionally, the endodontic brush can be held with its axis perpendicular to the cutter. Alternatively or additionally, the endodontic brush 206 can be held with its axis at an acute angle to the cutter. For example, holding the cutter at an acute angle to the cutter can result in uneven cutting of the strands (e.g., one side being longer than the other). In some embodiments, the cutter is driven to rotate by a motor 218. Optionally, the direction of the cutter's pivot is selected to maintain the twist of the wire in the core of the brush 105. For example, a diamond wheel can be operated at high rpm and against the twist direction of the cable fiber and / or the winding direction of the strands.

[0107] 3A and 3B show an embodiment of an endodontic brush that has been cut with shear clippers. In some cases, the shear clippers leave protruding strands 320 and / or trapped strands 322. For example, the trapped strands 322 may become wrinkled and / or crushed together. For example, this may prevent the brush from opening.

[0108] 3C and 3D show a section of an endodontic brush cut with an abrasive cutter rotating in the direction of the winding of the brush core, according to one embodiment of the present invention. As shown in the figures, the abrasive cutter causes little damage to the core 106 and cleanly cuts the distal ends 104 of the strands without wrinkles or tangles.

[0109] FIG. 4 is an image showing a channel being cleaned using a brush, according to one embodiment of the present invention. In some embodiments, a cleaning and / or disinfecting solution is injected into the channel. For example, the cleaning solution can include sodium hypochlorite. Optionally, the outer portion 428 of the channel is first cleaned with a file, and then the apical portion 430 of the channel is cleaned with a brush. Alternatively or additionally, the channel 428 is cleaned in a single step. For example, the brush includes a rough outer surface with a proximal portion that fills the walls of the outer portion 428 of the channel and a distal portion that is inserted into and / or cleans the apical portion 430 of the channel. Rotation of the brush can cause turbulence in the fluid. The turbulence (e.g., due to friction and / or momentum of the moving liquid) can clean areas of the channel (e.g., the fluid can clean the channel with and / or without contact with the brush, e.g., in lateral root canals 432 and / or areas not reached by the brush). In some embodiments, biofilm and / or plaque can be detached from the walls of the channel by contact with the file and / or brush and / or by disinfectants and / or turbulence.

[0110] FIG. 5 is an image of an exemplary experiment showing the effect of centrifugal force. In some embodiments, high rpm and / or elasticity of the brush create centrifugal force phenomena. Optionally, a dental handpiece 534 rotates the endodontic brush 506 within the channel. Centrifugal force optionally causes the brush to open at the apex of the channel. An open brush has a large cross-section and / or a large virtual mass and / or is efficient at imparting rotational energy to the fluid. For example, the fluid can be driven to rotate at high speeds and / or with high turbulence (which may be indicated, for example, in FIG. 5 by turbidity 536 and the white color of the fluid, indicating the presence of vortices and trapped air bubbles) and / or by deformation of the free surface 537. For example, at rotational speeds above 1500 rpm and / or particularly above 6000 rpm, the strands can open (e.g., creating a large paddle-like profile and / or a large virtual mass) and / or create high turbulence and / or high centrifugal force on the fluid within the channel. The centrifugal force and / or turbulence of the fluid can free obstructions (such as air bubbles, biofilm residue, root canal mucus, and / or plaque) and / or fluid in spaces (e.g., small apical channels, curved channels, dentin canals, and / or pores) that would be difficult to reach with a brush alone and / or fluid at low rotational speeds. Experiments have shown this results in improved channel disinfection and / or dental treatment outcomes (e.g., improved implant lifespan). In FIG. 5 , the high centrifugal force on the turbulent fluid causes the free surface 537 to tilt against gravity and / or rise along the channel wall. For example, a brush is shown pushing against the left side of the channel, causing the free surface of the fluid to rise along the left wall. In exemplary experiments, the high turbidity 536 of the fluid (e.g., its bright white color) is understood as an effect of high turbulence, which may have caused cavitation. In some embodiments, fluid cavitation can increase friction and / or wear on surfaces even when not reached by brush bristles. For example, this may reduce blockage and / or facilitate disinfection.

[0111] Figures 6A-6D show cross sections of exemplary channels cleaned according to one embodiment of the present invention. The channel surfaces were significantly cleaner than similar channels cleaned using conventional endodontic techniques. For example, Figure 6A shows a cross section of the apical portion 638a of a channel 2 mm from the tip, demonstrating that even a small apical channel is cleaned. For example, the narrow distal portion of the brush can penetrate the narrow apical portion of channel 638a and / or open under centrifugal force and / or clean the channel walls. Figures 6B and 6C show exemplary cross sections of the middle portion of a channel 4 mm and 6 mm from the tip, respectively. In the exemplary embodiment, the cross sections of channels 638b, 638c, and 638c' are thin and irregular (e.g., in 638c', the two apical channels of 638b appear to converge to form a larger, non-uniform channel), yet the file and / or turbulence clean the channel walls. For example, in portions 638b, 638c, and 638c', the whipping motion (e.g., due to the bending of the file and / or the flexing of the file under centrifugal force) can cause the roughened portion of the file (e.g., on the outer spiral wound wire) to contact and / or clean the walls of the channel. FIG. 6D shows an exemplary cross-section of the channel opening 8 mm from the tip. In the exemplary embodiment, the file and / or turbulent flow cleans the walls of the channel, even though the cross-section of channel 638d is irregular (e.g., in 638d, the two intermediate channels 638c and 638c' appear to converge to form a larger, irregular channel). For example, in this portion 638d, the whipping motion of the file and / or the flexing and / or the flexing of the file under centrifugal force can cause the roughened portion of the file (e.g., on the outer spiral wound wire) to contact and / or clean the walls of the channel.

[0112] 7 shows a 500x magnified surface 740 of the apex of a channel in a tooth that has been cleaned with an endodontic brush according to one embodiment of the present invention. The surface 740 is rough and has micropores 742, but appears clean. For example, the cleaning force of the brush may be the result of scraping by the brush strands and / or turbulence.

[0113] 8 is a flowchart of a method for cutting the distal end of an endodontic brush, according to one embodiment of the present invention. For example, the brush shaft may be set in a clamp 844. Optionally, the angle of the shaft relative to the cutter is fixed (e.g., perpendicular and / or at a finite angle). Optionally, an abrasive cutter is rotated 846 in a direction consistent with the windings of the strands to be cut (e.g., in the same direction and / or opposite to the windings). Optionally, the cutter then passes 848 through the strands, cutting them.

[0114] 9 is a flowchart illustrating cleaning an endodontic channel according to one embodiment of the present invention. For example, the coupler can lock 950 to a dental handpiece, e.g., preventing longitudinal movement relative to the handpiece and / or separation of the handpiece and brush. Optionally, the lock 950 does not prevent rotational slippage between the coupler and a fitting (e.g., a chuck) of the handpiece. For example, the locking element may be rotationally symmetric. For example, the grip 952 for the rotatable connection between the handpiece and coupler may be frictional. Optionally, the handpiece rotates 954 the brush unless a threshold torque is exceeded. Once the threshold torque is exceeded, the coupler optionally slides rotationally within the fitting of the handpiece without moving longitudinally relative to the handpiece and / or separating from the handpiece.

[0115] In some embodiments, the present invention provides a method for safely limiting torque imparted to an endodontic instrument (e.g., a brush and / or file) by a dental handpiece while avoiding separation of the instrument from the dental handpiece, the method comprising: inserting a coupler of the brush into a dental handpiece barrel to longitudinally lock the coupler to the handpiece; and optionally, imparting rotational motion to the brush solely based on friction between the handpiece and the coupler. For example, friction can be controlled by adjusting the diameter of the coupler and / or its material. For example, the coupler can comprise a resilient and / or flexible material (e.g., an elastomer) and / or a high coefficient of friction material (e.g., an elastomer). Optionally, the applied torque is limited by a squeezing force exerted on the coupler (which can be slightly larger than the handpiece barrel) during insertion into the barrel due to the coefficient of friction between the coupler and the handpiece barrel. Optionally, when shear force between the brush and the endodontic channel increases above a predetermined value, the coupler rotates and slides within the handpiece barrel. This prevents breakage of the instrument and / or undesired damage to the dentin layer. Longitudinal locking also prevents undesired release of the brush from the handpiece. For example, the outer diameter of the coupler can be within the ranges of 100.5-102% of the barrel diameter, and / or 102-105% of the barrel diameter, and / or 105-115% of the barrel diameter, and / or 115-150% of the barrel diameter. For example, the outer diameter of the coupler can be within the ranges of 2.3-2.36 mm, and / or 2.36-2.4 mm, and / or 2.4-2.5 mm. For example, the outer diameter of the coupler can be within the ranges of 2.0-2.05 mm, and / or 2.05-2.15 mm, and / or 2.15-2.25 mm.

[0116] FIG. 10 illustrates an endodontic instrument (e.g., brush and / or file) assembly according to one embodiment of the present invention. For example, the assembly can include a coupler 1056 having a locking element 1058 that locks the instrument to the handpiece against longitudinal forces and / or applies torque between the handpiece and the instrument with a frictional connection that allows slippage above a threshold torque. For example, the coupler 1056 can fit into a standard D-ring fitting on a dental handpiece. Optionally, the coupler 1056 can be rotationally symmetric to lock to the fitting but allow rotational slippage. For example, the fitting and / or coupler 1056 can be configured to limit torque between the handpiece and the instrument. For example, the frictional fit can allow slippage at torques greater than 0.05 Ncm, and / or greater than 0.01 Ncm, and / or greater than 0.1 Ncm, and / or greater than 0.5 Ncm, and / or greater than 1 Ncm. Optionally, coupler 1056 can have standard sizes, e.g., 2.35 mm, 3.0 mm, and / or 3.175 mm diameter. Alternatively or additionally, the fitting can include a circular spindle for connection to a standard chunk. Alternatively or additionally, other types and / or sizes of fittings are possible, e.g., 1-2.5 mm, and / or 2.5-3.5 mm, and / or 3.5-7 mm.

[0117] In some embodiments, the intermediate portion 1060 of the instrument includes a core 1006 (e.g., comprising a cable) that is constrained, for example, by a helically wound wire 1008. Optionally, the instrument can include an unconstrained distal portion 1002, and the core 1006 can optionally be unconstrained and / or open into a brush.

[0118] 11A and 11B show an endodontic instrument according to one embodiment of this embodiment. In FIG. 11A, the instrument is shown before being attached to a handle (e.g., coupler 1156). In some embodiments, a proximal portion 1157 of the instrument is bent and / or folded within the coupler 1156. For example, bending the distal end of the instrument may make it easier to connect the instrument to the coupler 1156. Additionally or alternatively, bending the proximal portion of the instrument can cause the instrument to fit eccentrically into the coupler 1156 and / or facilitate a whipping motion of the instrument. For example, the coupler may be in the form of a hollow tube (e.g., the hollow may be open on one or two sides). Optionally, the coupler 1156 can be made of a flexible and / or high-friction material (e.g., rubber, elastomer, and / or plastic). Optionally, the bent portion 1157 of the instrument is packed into the hollow portion of the coupler.

[0119] 12 is a schematic diagram of an endodontic brush according to an embodiment of the present invention. In some embodiments, the brush includes an intermediate portion 1260 and / or a distal portion 1202. Optionally, the intermediate portion 1260 includes a core 1206 (e.g., including multiple strands and / or twisted cables) and / or a surrounding helical winding 1208. At the distal portion 1202, the core 1206 optionally protrudes and / or is unbonded. Optionally, toward the distal portion 1202, the helical winding 1208 may be unwound. For example, the distal portion 1262 of the winding 1208 may be oriented parallel and / or approximately parallel to the core 1206 and / or the axis of the instrument. For example, at the distal portion 1202, the width (e.g., diameter) of the instrument may be the core thickness 1279. For example, at intermediate section 1260, the width (e.g., diameter) of the instrument may be the sum of the thickness 1279 of the core and twice the thickness 1277 of the helical winding 1208. Optionally, if the helical winding 1208 is unwound, for example, between intermediate section 1260 and distal section 1202, the width of the instrument will be between the width 1272 of intermediate section 1260 and the width of distal section 1202. For example, at section 1262 where the winding 1208 is parallel to the core, the width 1274 of the instrument is the sum of the width of the core 1206 and the width 1277 of the winding 1208.

[0120] The inventors have observed that, in some cases, endodontic files can damage the root canal. For example, if the outer winding 1208 is rotated counter to the winding direction, the rigid wire of the outer winding can protrude into and / or damage the root canal. For example, the distal tip of the outer winding can protrude outward and scrape the walls of the channel. In some embodiments, the distal tip of the outer winding can be blunt and / or oriented in a direction that reduces the likelihood of damage. For example, the distal tip can be oriented parallel to the core, which can reduce the likelihood of damage to the channel.

[0121] In some embodiments, the brush and / or file can include a single winding 1208 wrapped around the core 1206. For example, the core 1206 can include a cable with multiple strands. For example, the strands can all be twisted in the same direction as the outer winding 1208. Alternatively or additionally, the strands can all be twisted in the opposite direction to the outer winding 1208. Alternatively or additionally, the core 1206 can include untwisted strands and / or strands twisted in different directions.

[0122] In some embodiments, the width 1277 (e.g., diameter) of the winding 1208 can be in the range of 0.15-0.25 mm, and / or 0.25-0.3 mm, and / or 0.3-0.4 mm, and / or 0.05-0.15 mm, and / or 0.4-0.7 mm.

[0123] In some embodiments, the width 1279 (e.g., diameter) of the core 1206 can be in the range of 0.15-0.25 mm, and / or 0.25-0.3 mm, and / or 0.3-0.4 mm, and / or 0.05-0.15 mm, and / or 0.4-0.7 mm.

[0124] In some embodiments, the width 1272 (eg, diameter) of the intermediate portion 1260 can be in the range of 0.25 to 0.4 mm, and / or 0.4 to 0.7 mm, and / or 0.7 to 0.9 mm, and / or 0.9 to 1.2 mm.

[0125] In some embodiments, width 1274 (e.g., diameter) of transition section where winding 1208 unwinds between intermediate section 1260 and distal section 1202 can be in the range of 0.1 to 0.25 mm, and / or 0.25 to 0.7 mm, and / or 0.7 to 1.0 mm. Optionally, length 1276 of transition section can be in the range of 0.1 mm to 0.4 mm, and / or 0.4 mm to 0.8 mm, and / or 0.8 mm to 1.6 mm, and / or 1.6 mm to 3.2 mm. Optionally, winding 1208 is the same at the fully wrapped section (e.g., intermediate section 1260) and the transition section.

[0126] In some embodiments, the length 1278 of the distal portion 1202 can be in the range of 0.1 mm to 0.4 mm, and / or 0.4 mm to 0.8 mm, and / or 0.8 mm to 1.6 mm, and / or 1.6 mm to 3.2 mm, and / or 3.2 to 7 mm, and / or 7 to 10 mm, and / or 10 to 20 mm.

[0127] In some embodiments, the intermediate portion 1260 and / or the distal portion 1202 can be bent and / or flexible and / or corrugated. Optionally, the outer portion of the instrument (e.g., the helical winding 1208) can be roughened (e.g., by titanium plasma spray (TPS), dual acid etching (DAE), large grit sandblast acid etching (SLA), anodizing (ANO), machining (MAC), silica coating (Sc), sandblasting (Sb), metal primer, coupling agent, fiber (Fb) application, and opacifier (O)). In some embodiments, materials such as silanes, metal primers, or adhesives (Visiobond [V], Magnetic Photobond [PP], Alloy Primer [AP], Unibond Sealant [Us], ESPE-Sil [ES]), and / or opacifying agents, such as Clearfil St Opaquer (CstO), Sinfony (S), Miris (M), and / or EO-Cavex), can be used for roughening.

[0128] 13 is a schematic diagram of an endodontic brush with an extended end, according to one embodiment of the present invention. Optionally, width 1277 of windings 1308 is the same as the width of the fully wrapped portion (e.g., middle portion 1260) and is greater than the width of windings 1308 in the transition portion. For example, the windings may be malleable (e.g., metal wire) and are unwound and / or extended and / or narrowed at transition portion 1362 near the distal end. For example, width 1374 of transition portion 1362 may be less than the sum of width 1279 of core 1206 and the width of windings 1308 in middle portion 1260.

[0129] In some embodiments, the windings 1308 can be configured to resist unwinding. For example, when the brush is rotating in the unwinding direction of the helical windings 1308, the windings 1308 can resist unwinding. Optionally, the distal portion and / or distal end of the windings 1308 can be thick enough to resist unwinding. In some embodiments, stretching the windings 1308 and / or orienting the tip of the windings 1308 in a selected direction different from the proximal portion of the windings 1308 (e.g., unwinding the distal portion and / or orienting the distal tip parallel to the core 1206) can facilitate narrowing the distal portion of the file (e.g., the distal portion of the windings 1308) with reduced risk of damaging the channel.

[0130] In some embodiments, the brush and / or file can include a single winding 1308 wrapped around the core 1206. For example, the core 1206 can include a cable with multiple strands. For example, the strands can all be twisted in the same direction as the outer winding 1308. Alternatively or additionally, the strands can all be twisted in the opposite direction to the outer winding 1308. Alternatively or additionally, the core 1206 can include untwisted strands and / or strands twisted in various directions.

[0131] 14 is a schematic diagram of an eccentric endodontic brush, according to one embodiment of the present invention. In some embodiments, the distal portion 1402 of the instrument includes a brush, for example, to clean the apical portion of the channel. Optionally, the middle portion 1460 can be roughened and / or bendable and / or flexible. For example, the roughened portion of the middle portion 1460 can be configured to scrape the sides of the channel. For example, the middle portion 1460 and / or the distal portion 1402 can include bending and / or eccentricity. For example, the bending and / or eccentricity and / or flexibility can allow the file and / or brush to be whipped back and forth within the channel.

[0132] 15 is a schematic diagram of an eccentric endodontic brush, according to one embodiment of the present invention. In some embodiments, the distal portion 1502 of the instrument includes a brush, for example, for cleaning the apex of the channel. Optionally, the middle portion 1560 can be roughened and / or bent and / or flexible. For example, the roughened portion of the middle portion 1560 can be configured to scrape the sides of the channel. For example, the middle portion 1560 and / or the distal portion 1502 can include multiple bends and / or can be corrugated and / or eccentric. For example, the bends and / or eccentricity and / or flexibility can allow the file and / or brush to be whipped back and forth within the channel.

[0133] 16 shows an endodontic brush in a simulated channel, according to one embodiment of the present invention. In some embodiments, a curved endodontic brush is rotated inside a channel 1680. Optionally, the brush includes a roughened edge. For example, a middle portion 1560 of the brush can be surrounded by a helical wire 1608. The helical wire 1608 is optionally roughened. Optionally, the brush is curved and / or flexible and / or eccentric to the rotation so that various portions of the brush's sides scrape against the walls of the channel 1680 and clean the channel. At the narrow tip of the channel, optionally, a narrow core exposed at the distal portion 1502 of the brush can penetrate and / or expand to clean the walls of the channel 1680 and / or create movement in the fluid to clean the channel.

[0134] FIG. 17 illustrates an endodontic brush with a roughened edge according to one embodiment of the present invention. For example, the outer edge can include the surface of the outer windings 1708 of the brush. For example, the outer edge can be roughened by, for example, titanium plasma spray (TPS), dual acid etching (DAE), coarse-grain sandblasted acid etching (SLA), anodizing (ANO), machining (MAC), silica coating (Sc), sandblasting (Sb), metal primer, coupling agent, fiber (Fb) application, and opacifying agent (O). In some embodiments, materials such as silane, metal primer, or adhesive (Visiobond [V], Magnetic Photobond [PP], Alloy Primer [AP], Unibond Sealant [Us], ESPE-Sil [ES]), and / or opacifying agent (e.g., Clearfil St Opaquer (CstO), Sinfony (S), Miris (M), and / or EO-Cavex) can be used for roughening. Optionally, the brush can be bent and / or eccentric. Optionally, the distal end of the brush can be cut unevenly and / or cut using an abrasive cutter. Optionally, the distal portion 1762 of the helical winding can be unwound and / or parallel to the core 1206. Optionally, the distal portion of the helical winding can be sharpened and / or extended and / or left the same as the middle portion. The various dimensions of the brush of FIG. 17 may be for any other embodiment disclosed herein.

[0135] 18 is a block diagram of an eccentric endodontic file 1801, according to one embodiment of the present invention. In some embodiments, the file 1801 includes a proximal handle 1802 and a distal active part 1806. Optionally, the proximal handle 1802 is configured to rotate about an axis of rotation (e.g., the handle can include a fitting configured to mate with a dental handpiece and / or rotate the dental handpiece about an axis of rotation, e.g., the axis of rotation can be an axis of symmetry for all or part of the handle). Optionally, the distal active part 1806 of the file 1801 is eccentrically and / or asymmetrically attached to the handle. For example, the local center of mass of the distal active part 1806 can be displaced from the center of rotation of the handle. For example, the local center of mass of the distal active part 1806 can be misaligned with the axis of rotation of the handle and / or can be entirely on one side of the axis of rotation of the handle. For example, the average center of mass of the distal active portion 1806 can be displaced away from the axis of rotation of the handle by a distance from the radius of the handle to twice the radius of the handle, and / or more than twice the radius of the handle, and / or from one-half the radius to the radius of the handle. In some embodiments, the flexible active portion 1806 distal to the transition portion 1804 is generally parallel to the axis of rotation of the handle 1802 in an unstressed state. For example, the distance between the axis of rotation and the local center of mass of the flexible active portion 1806 distal to the transition portion 1804 can be approximately fixed along the length of the flexible active portion 1806, e.g., from the transition portion 1804 to and / or near the distal tip of the file 1801.

[0136] In some embodiments, file 1801 can include a transition region 1804. For example, along the transition region, the distance from the file's local center of gravity to the handle's axis of rotation can increase. Optionally, transition region 1804 is less flexible than distal active region 1806. Optionally, transition region 1804 is more flexible than proximal handle 1802. In some embodiments, transition region 1804 is part of the active region of file 1801 (e.g., the active region can be a flexible wire and / or can include a rough coating for cleaning the root canal). Alternatively or additionally, the transition region is part of the handle (e.g., the handle can be made of plastic and / or a rigid material).

[0137] In some embodiments, the handle 1802 can include a friction fit and / or a locking fit. For example, the locking fit can include a D-ring. Optionally, the handle material can include plastic and / or metal. In some embodiments, the handle can include a torque limiter. For example, the friction fit can slip between the handpiece and / or file at high torques (e.g., torques greater than 30 g / (cmN), and / or greater than 100 g / (cmN), and / or greater than 5 g / (cmN)). Alternatively or additionally, the handle can include a lock that transmits high torque between the dental handpiece and the file.

[0138] FIG. 19 is a flowchart illustrating endodontic root canal cleaning, according to an embodiment of the present invention. In some embodiments, an eccentric endodontic file can be delivered 1901 (e.g., the file can include any of the embodiments described herein). Optionally, a proximal handle of the file is attached to a rotation source (e.g., a dental handpiece) 1902. In some embodiments, a flexible distal portion of the file is inserted 1906 into the root canal requiring cleaning. Optionally, the handle is rotated 1903 (e.g., by the dental handpiece) about an axis of rotation. For example, file rotation 1903 can be initiated after insertion 1906 of the distal tip into the root canal. Handle rotation 1903 optionally causes a rotational whipping motion 1908 of a flexible portion of the file distal to the handle. For example, whipping motion 1908 can occur at a transition section and / or a portion of the flexible distal section of the file. Optionally, whipping motion 1908 can occur at a portion of the file inside the root canal. Alternatively or additionally, a portion of the flexible distal portion of the file (e.g., the middle and / or distal tip of the flexible distal portion) can be whipped within the root canal 1908. Optionally, the whipping motion can cause the active flexible portion of the file inside the root canal to clean the root canal and / or contact the root canal wall over a larger area than a simple rotational motion. For example, the whipping flexible portion can be whipped over a much larger area than the file itself.

[0139] In some embodiments, the file includes a brush, for example, at the distal end. Optionally, rotation of the file 1903 opens the brush. For example, the brush can be inserted 1906 and / or rotated 1903 and / or opened into the distal (e.g., apical) portion of the root canal. Optionally, the brush can clean the apical portion of the root canal. For example, cleaning can include wall scraping, turbulence, and / or chemical activation. Optionally, the brush can be inserted 1906 without rotation 1903 and / or with rotation in a winding direction and / or with rotation in an unwinding direction 1903.

[0140] 20 is a block diagram of a kit 2001 including an eccentric endodontic file, according to one embodiment of the present invention. Optionally, the file can include an eccentric endodontic file, e.g., as described in any of the embodiments described herein. For example, the file can include a handle 2002 and / or a transition portion 2004 (optionally distal to the handle) and / or an active portion 2006 (optionally distal to the transition portion). Optionally, the eccentric file is supplied and / or packaged in an unstressed state. Optionally, the center of gravity of the active portion 2006 is not on the axis of rotation of the handle 2002. Optionally, the file is packaged in a package 2010 (e.g., a box and / or tray and / or bottle and / or packet) for distribution (e.g., sale). Alternatively or additionally, the file is packaged for sterility. For example, the file can be packaged in a sterile package 2010. For example, the sterile package can include a bacterial barrier, such as a woven material, a rigid container, a paper-plastic peel pack, or the like, that conforms to standards (e.g., ANSI (The Association of Surgical Technologies) and AAMI (The Association of Medical Instrumentation) standards). For example, the sterile package can withstand heat sterilization and / or gas permeation for EtO and / or gas and / or plasma sterilization. Optionally, the package 2010 can include a tray. In some embodiments, the kit can include files and / or sterilization materials and / or packaging. For example, the package can include glass, paper, plastic, and / or metal containers. For example, the package can include fibrous materials, films, foils, and / or laminates. In some embodiments, the package can be closed and / or sealed. For example, the seal can include a gasket and / or a filter and / or an adhesive and / or a heat seal.

[0141] 21 is a flowchart illustrating the production of a kit including an eccentric endodontic file, according to one embodiment of the present invention. For example, an eccentric file (e.g., according to any of the embodiments described herein) can be provided for packaging 2101. Optionally, the file is provided in a stress-free and / or sterile and / or clean state 2101. Optionally, the file is sterilized 2112 and / or packaged 2110. In some embodiments, the file can be sterilized 2112 and then packaged 2110 (e.g., autoclaved and then placed in a clean access tray in a clean room). Alternatively or additionally, the file can be packaged 2110 and then sterilized 2112 (e.g., using sterilization packaging and techniques listed herein). In some embodiments, the package can be closed. For example, closing can include sealing the package. The seal can be airtight and / or include a bacterial barrier and / or a filter. Optionally, sealing may include crimping, screwing a cap, gluing, heat sealing, folding, coating, and / or shrink sealing.

[0142] FIG. 22 is a schematic diagram of an eccentric endodontic file 2201, according to one embodiment of the present invention, and FIG. 23 is a schematic diagram of a local average center of gravity of an eccentric endodontic file, according to one embodiment of the present invention. The file of FIG. 22 can include files as described in other embodiments herein. Optionally, file 2201 includes a proximal handle 2202 having an axis of rotation 2218. Optionally, the file includes an active portion 2207. The active portion 2207 can include a central core 2211 and / or one or more helical wires 2213 surrounding the central core. Optionally, the central core includes a wire and / or cable, for example, made of multiple fine strands. In some embodiments, the active portion 2207 can include a transition section 2204 and / or an eccentric distal active portion 2206. Alternatively or additionally, the transition section may comprise a portion of the handle (e.g., the active section may be attached to the handle eccentrically relative to the axis of rotation of the handle, e.g., obliquely relative to the axis of rotation and / or translated away from the axis of rotation).

[0143] In some embodiments, handle 2202 can have a width (e.g., diameter 2216d) of 1.3 to 2.9 mm, and / or 2.9 to 3.2 mm, and / or 3.2 to 3.5 mm, and / or greater than 3.5 mm. For example, handle 2202 can be fitted with a friction fit of 2 mm and / or a friction fit of 3.35 mm. For example, handle 2202 can have a length 2216a in the range of 5 to 9 mm, and / or 2 to 5 mm, and / or 9 to 15 mm. Optionally, handle 2202 can have an axis of rotation 2218. For example, axis of rotation 2218 can pass through the center of mass and / or center of gravity 2224 of the handle. For example, axis of rotation 2218 can correspond to the local center of mass 2222 of handle 2202 along its length. Optionally, in the unstressed shape, distal active portion 2206 is approximately straight. Alternatively or additionally, in the unstressed shape, the distal active portion 2206 can have a constant second moment (eg, the distal active portion is curved in the same direction along its entire length).

[0144] In some embodiments, the concentric portion 2209 of the active portion 2207 of the file 2201 may be concentric with the axis of rotation of the handle 2202. For example, the concentric portion 2209 can be located between the transition section 2204 and the handle 2202. Alternatively, the transition section can be directly connected to and / or include a portion of the handle 2202. In some embodiments, as one moves distally along the transition section 2204, the local center of mass 2222 of the file can be further away from the axis of rotation 2218 of the handle 2202. For example, the transition section can have a length 2216b within the range of 1-2 mm, and / or 2-6 mm, and / or 6-12 mm, and / or 12-25 mm. Optionally, lateral displacement 2216e between the proximal beginning of transition section 2204 and the distal end of transition section 2204 can be in the range of 0 to 1.5 mm, and / or 1.5 to 2.2 mm, and / or 2.2 mm to 4 mm, and / or 4 to 10 mm.

[0145] In some embodiments, the distal active region 2206 is located distal to the transition region 2204. For example, the distal active region 2206 can be connected to the handle via the transition region 2204. Optionally, the distal active region 2206 is approximately parallel to the axis of rotation 2218 of the handle when the file 2201 is unstressed. Alternatively or additionally, the distal active region 2206 can be oblique and / or curved relative to the axis of rotation 2218 of the handle when the file 2201 is unstressed. In some embodiments, the distal active region 2206 can all be on one side of the axis of rotation 2218. Optionally, the length of the distal active portion 2216f can be in the range of 15-20 mm, and / or 5-15 mm, and / or 20-30 mm.

[0146] In some embodiments, the distance from the center of mass 2227 of the file 2201 to the axis of rotation 2218 of the handle 2202 is greater than the radius of the file's handle 2202. Alternatively or additionally, the distance from the center of mass 2227 of the file 2201 to the axis of rotation 2218 of the handle 2202 may be less than the radius of the file's handle 2202 (e.g., between one-half the radius and the radius). In some embodiments, the distance from the center of mass 2225 of the distal active part 2206 of the file 2201 to the axis of rotation 2218 of the handle 2202 is greater than the radius of the file's handle 2202. Alternatively or additionally, the distance from the center of mass 2225 of the distal active part 2206 of the file 2201 to the axis of rotation 2218 of the handle 2202 may be less than the radius of the file's handle 2202 (e.g., between one-half the radius and the radius). In some embodiments, the center of mass 2227 of file 2201 is closer to the axis of rotation of file handle 2202 than the center of mass 2225 of distal active portion 2206. In some embodiments, the center of mass 2227 of file 2201 is closer to file handle 2202 than the file's local center of mass 2222 along distal active portion 2206 (e.g., distal to file transition section 2204). Optionally, the overall length of file 2216c can be in the range of 30-34 mm, and / or 20-30 mm, and / or 34-45 mm.

[0147] In some embodiments, the distal active portion 2206 may be thinner and / or more flexible than some or all of the proximal portion of the file (e.g., the transition portion 2204, and / or the concentric portion 2209, and / or the handle 2202). Optionally, the distal active portion 306 is tapered. For example, the distal active portion may terminate in a tapered tip.

[0148] In some embodiments, the core 2211 can protrude outward from one or more of the helical wires 2213. For example, at the distal end, the core 2211 can be exposed. For example, the core 2211 can include a multi-strand cable that opens up as a brush at the distal end of the device when the device is rotated in a particular direction. For example, the file can be inserted while rotating in a first direction, and / or the direction of rotation can be reversed, opening the strands at the distal end of the file to form a brush and / or clean the sides of the root canal. Contact with the root canal wall can further open the strands. Optionally, the distal portion of the file has a very small diameter and / or is sufficiently flexible to penetrate the very small apex of the root canal. The rotating brush optionally activates disinfecting chemicals. Optionally, the rotation of the brush can drive fluid (e.g., disinfectant) into the stoma (e.g., by creating turbulence, centrifugal force, and / or removing a film that blocks the stoma).

[0149] 24 is a schematic illustration of a whipping motion of an eccentric endodontic file, according to one embodiment of the present invention. In some embodiments, the axis of rotation 2418 of the file 2401 does not correspond to an axis of symmetry of the active portion of the file 2401 (e.g., the transition region 2404 and / or the distal active region 2406). In some embodiments, when the file 2401 is rotated 2430 about the axis of rotation 2418 of the handle 2402, centrifugal force optionally stresses the distal active region 2406 outward (e.g., away from the axis of rotation 2418). Optionally, the whipping and / or spreading is distributed over the entire length of the transition region 2404 and / or the distal active region 2406 of the file 2401. For example, as the transition region 2404 rotates between opposing positions 2404, 2404′ and / or the distal active region 2406 rotates between opposing positions 2406, 2406′, the distal portion of the file 2401 can whip and / or spread around. For example, when the distal portion of the file 2401 is within the root canal, the distal tip can whip around large spaces within the root canal and / or contact and / or clean the sides of the root canal. This whipping motion can clean corners and / or hard-to-reach places within the root canal. The whipping motion can also whip irrigation fluid within the root canal to activate the irrigation fluid and / or mix the irrigation fluid deeper within the root canal, for example, to clean and / or disinfect channels. In some embodiments, the transition region 2304 is attached directly to the handle 2402 of the file.

[0150] FIG. 25A is a schematic diagram of an eccentric endodontic file shallowly inserted into a root canal, according to one embodiment of the present invention, and FIG. 25B is a schematic diagram of an eccentric endodontic file 2201 deeply inserted into a root canal of a tooth 2534 and rotated by a dental handpiece 2532, according to one embodiment of the present invention. In some embodiments, the whipping action of file 2201 self-adjusts to the space and / or geometry within the root canal. For example, as file 2201 is inserted into the root canal, an active portion of the file proximal to the root canal, e.g., transition portion 2204, whips around and / or causes the distal portion to scrape against the edge of the large opening of the root canal. The whipping of transition portion 604 outside the root canal also optionally causes a whipping motion within the distal portion. The whipping motion optionally affects all portions of the distal active portion of file 2201 in the same way. For example, this causes file 2201 to contact the wall all along the distal active portion. In some embodiments, the curvature and / or flexibility and / or bending force causes portions of the file to expand in volume (e.g., as the file elastically buckles) to fill the root canal and / or scrape edges around the root canal.

[0151] FIG. 26A is a low-magnification image of an eccentric endodontic file 2201 according to one embodiment of the present invention, FIG. 26B is a medium-magnification image of an eccentric endodontic file 2201 according to one embodiment of the present invention, and FIG. 26C is a high-magnification image of section B (shown in FIGS. 26A and 26B) of an eccentric endodontic file after use according to one embodiment of the present invention. The whipping of the file can be seen to cause a substantially uniform wear of the abrasive surface of the file. For example, movement of the file can cause the whipping and / or spreading and / or contact with the surface of the root canal along the active part of the file. For example, when the axis of rotation of the file 2201 does not correspond to the center of mass of the active part of the file, centrifugal force can press the active part against the wall of the root canal along its entire length. For example, the center of mass of the distal active part of the file 2201 can extend substantially parallel to the axis of rotation. Optionally, the centrifugal movement and / or whipping generates a centrifugal force between the active part of the file and the wall of the root canal. Optionally, this force is distributed throughout the distal active portion of the file. For example, the rotational speed of an eccentric file can be in the range of 4000-5500 RPM, and / or 5500-7500 RPM, and / or 7500-9500 RPM. Optionally, the file 2201 resists material fatigue and / or stress concentrations (e.g., due to flexibility and / or resilience, contact with the root canal, and / or a substantially constant distance between the unstressed active portion of the file and the axis of rotation). In some embodiments, the flexible helical design of the active region of the file 2201 under stress equalizes pressure and facilitates movement of structures on the file. For example, dynamic loading, bending, elastic buckling, and / or deflection of the file can cause different portions of the file to contact the root canal wall at different times. This may also facilitate stress distribution.

[0152] FIG. 27A is a highly enlarged schematic view of a longitudinal section (section A of FIG. 22) of an eccentric endodontic file, according to one embodiment of the present invention. In some embodiments, the structure of the active portion of the file can include a central core 2714 (e.g., the diameter of the core can be, for example, in the range of 0.05-0.2 mm, and / or 0.01-0.05 mm, and / or 0.2-0.4 mm). Optionally, core 2714 can include single and / or multiple thin strands. For example, each strand can have a diameter of 0.01-0.05 mm, and / or 0.05-0.1 mm, and / or 0.1-0.2 mm. The strands are optionally twisted together. For example, the strands can be twisted in the opposite direction from helical wires 2744 and / or 2746. Alternatively or additionally, the strands can be wound in the same direction as helical wires 2744 and / or 2746. Optionally, a medium diameter wire 2744 (e.g., having a diameter in the range of 0.05-0.1 mm, and / or 0.1-0.25 mm, and / or 0.25-0.5 mm) is tightly wound around core 2714 (e.g., distance 2716a between windings is 100%-110%, and / or 110%-130%, and / or 130%-150%, and / or 150%-200% of the diameter of medium wire 2744). Optionally, a large diameter wire 2746 (e.g., having a diameter in the range of 0.1-0.2 mm, and / or 0.2-0.5 mm, and / or 0.5-1 mm) is loosely wrapped around a medium wire 2744 (e.g., the distance 2716b between windings can be in the range of 120%-150%, and / or 150%-200%, and / or 200%-400%, and / or 400%-900% of the diameter of the large wire 2746). Optionally, near the tip of the file, the core 2714 and / or wires 2744, 2746 can be tapered. Alternatively or additionally, the large wire 2746 can be absent and / or the medium wire can be absent near the distal tip of the file.Optionally, one or all of core 2714 and / or the outer wire near the tip (e.g., wire 2746 in section A, and / or wire 2744, and / or core 2714) can be treated to have a surface roughness (e.g., as shown in FIG. 26C). Optionally, at the tip, the strands of core 2714 can be freed (e.g., to form a brush) and / or melted (e.g., to form a file).

[0153] FIG. 27B is a highly enlarged longitudinal schematic view of a two-layered eccentric endodontic file according to one embodiment of the present invention. Any of the file and / or brush embodiments described herein can be fabricated with two-layer and / or three-layer constructions. In some embodiments, the construction of the active portion of the file can include a central core 2742 (e.g., the diameter 2743 of the core 2742 can be, for example, in the range of 0.1-0.3 mm, and / or 0.01-0.1 mm, and / or 0.3-0.5 mm). Optionally, the core can include a single wire and / or multiple fine strands. For example, the core 2742 can include 4-10 strands, and / or 1-4 strands, and / or 10-30 strands. For example, each strand can have a diameter of 0.03-0.1 mm, and / or 0.1-0.2 mm, and / or 0.01-0.03 mm. The strands can optionally be twisted together. For example, the strands can be twisted in the opposite direction to the helical wire 2747. Alternatively or additionally, the strands can be wound in the same direction as the helical wire 2747. Optionally, the helical wire 2747 has a diameter in the ranges of, for example, 0.05-0.1 mm, and / or 0.1-0.25 mm, and / or 0.25-0.5 mm, and / or 0.5-1.0 mm and is wound around the core 2742 (e.g., the distance between windings 2747 can be in the ranges of 100%-110%, and / or 110%-130%, and / or 130%-150%, and / or 150%-200%, and / or 200%-400%, and / or 400%-900% of the diameter of the wire 1047). Optionally, near the tip of the file, core 2742 and / or wire 2747 can be tapered. Alternatively or additionally, helical wire 2747 can be absent near the distal tip of the file. Optionally, one or all of core 2742 and / or helical wire 2747 near the tip can be treated to have a surface roughness (e.g., as shown in FIG. 26C ). Optionally, at the tip, the strands of core 2742 can be freed (e.g., to form a brush) and / or melted (e.g., to form a file).

[0154] FIG. 28A is a schematic diagram of a waveform file with brush tips, according to one embodiment of the present invention.

[0155] In some embodiments, the file includes strands 2811 that serve as brushes for cleaning the root canal and / or agitating fluids within the root canal. For example, the core of the file can include a cable with multiple strands. Optionally, on the body 2807 of the file, the core is surrounded by one or more helical wires 2804. In some embodiments, the core and / or helical wire 2804 can be wound in the same direction. Rotating the file in one direction can wind the helical wire 2804 and / or tighten the windings of the core, which can facilitate penetration of the file into the root canal. Optionally, rotating the file in the opposite direction can open the strands 2811 and / or expand the helical wire 2804. For example, opening the strands 2811 can form brushes for cleaning structures (e.g., narrow channels and / or foramina) within the apical portion of the root canal. Opening the helical wire 2804 can improve scraping of the proximal root canal walls. Alternatively or additionally, optionally, the rotation of the brush breaks up plaque and / or residue within the root canal and / or scrapes the walls of the root canal. Optionally, the file can have a multi-strand construction that resists stress and / or facilitates high-speed rotation while cleaning the root canal. The file construction can be as described herein above with reference to, for example, FIGS. 5, 26A-26C, and / or 10. Optionally, the file can include a proximal adapter 2802 that mates with a dental handpiece. For example, the handpiece can rotate the file at speeds of 5500-7500 RPM, and / or 3000-5500 RPM, and / or 2000-5500 RPM, and / or 7500-11000 RPM.

[0156] In some embodiments, a single file and / or pair of files can be used to clean the entire root canal. For example, the file can include distal strands 2811 that form brushes for cleaning the apex of the root canal. The strands 2811 optionally simultaneously clean the walls of the root canal and / or mobilize fluid within the root canal. For example, the swirling strands 2811 can create turbulence that forces liquid (e.g., disinfectant) throughout the root canal and / or toward the sides of the root canal. Additionally or alternatively, the strands 2811 scrape and / or remove biofilm and / or other coatings that shield infectious organisms from attack by the disinfectant. Optionally, this cleaning can facilitate the disinfectant's penetration of the biofilm layer and / or removal of bacteria.

[0157] In some embodiments, the body 2807 of the file can clean the outer portion of the root canal. For example, the file can be highly flexible and thus whip and / or bend and / or fold within the root canal to fill spaces and / or scrape the root canal walls and / or activate antiseptic fluids within the root canal. Optionally, a rotating helical winding on the file can evacuate plaque from the root canal. Optionally, cleaning the outer portion can occur simultaneously with cleaning the apex. Optionally, the file can have an eccentric configuration, as shown, for example, in FIG. 22. An eccentric configuration can be beneficial, for example, to create a whipping motion to create a large open area near the entrance to the root canal. Alternatively or additionally, the file can have a serpentine geometry (e.g., as shown in FIG. 28A). For example, the serpentine configuration can include curvatures throughout all and / or a majority of the length of the file (e.g., greater than 10%, and / or 10-25%, and / or 25-50%, and / or 50-75%, and / or 5-10%, and / or 2-5% of the file can be curved at rest). The serpentine geometry can facilitate elastic buckling of the file under axial pressure (e.g., as the dentist forces the file into the channel). The elasticity and / or buckling of the file can cushion the axial force, limiting the force exerted on the distal point of the file (e.g., preventing the distal end of the file from being forced out of the root canal and into the sensitive tissue surrounding the tooth). The buckling along the file can optionally push the file outward along its length filling the sides of the root canal. This can be particularly useful when cleaning the middle portion of the root canal (e.g., between the apex and the lateral portion). Optionally, the resilient curved structure of the serpentine file also redistributes forces, so that a portion of a high local lateral force that presses against the wall at one location, causing buckling, is distributed along the file, causing buckling at another location, preventing very large concentrated local forces from damaging and / or impacting the root canal wall.Optionally, the radius of curvature of the curved portion of the body of the file at rest can be within the ranges of 1-3 mm, and / or 3-10 mm, and / or 10-30 mm, and / or 30-50 mm, and / or 50-100 mm, and / or 100-300 mm. Optionally, the file can be sufficiently flexible to elastically buckle to a radius of curvature within the ranges of 0.2-1 mm, and / or 1-2 mm, and / or 2-4 mm, and / or 4-8 mm, and / or 8-16 mm. In some embodiments, the corrugated file with brush tips has a three-layer structure (e.g., as shown in FIG. 27A). Alternatively or additionally, the corrugated file with brush tips can have a two-layer structure (e.g., as shown in FIG. 27B).

[0158] 28B is a schematic diagram of a waveform file, according to one embodiment of the present invention. Optionally, the file includes a closed tip (e.g., rather than a brush). In some embodiments, the waveform file has a three-layer structure (e.g., as shown in FIG. 27A). Alternatively or additionally, the waveform file may have a two-layer structure (e.g., as shown in FIG. 27B).

[0159] In some embodiments, the file tip is an obturator file 2811′ for penetrating and / or cleaning the root canal. For example, the core of the file can include a cable having multiple strands. Optionally, on the body 2807 of the file, the core is surrounded by one or more helical wires 2804. In some embodiments, the core and / or the helical wire 2804 can be wound in the same direction. Rotating the file in one direction can wind the helical wire 2804 and / or tighten the windings of the core, which can facilitate penetration of the file into the root canal. Optionally, the file can have a multi-strand structure that resists stress and / or facilitates high-speed rotation while cleaning the root canal. The file's structure can be as described herein, for example, with reference to FIGS. 22, 26A-26C, and / or 27. Optionally, the file can include a proximal adapter 2802 that fits into a dental handpiece. For example, the handpiece may rotate the file at speeds of 5500-7500 RPM, and / or 3000-5500 RPM, and / or 2000-5500 RPM, and / or 7500-11000 RPM.

[0160] In some embodiments, the body 2807 of the file can clean the outer portion of the root canal. For example, the file can be highly flexible and thus can whip and / or bend and / or fold within the root canal to fill spaces and / or scrape the root canal walls and / or activate antiseptic fluids within the root canal. Optionally, a rotating helical winding on the file can evacuate plaque from the root canal. Optionally, cleaning the outer portion can occur simultaneously with cleaning the apex. Optionally, the file can have an eccentric configuration, for example, as shown in FIG. 22. An eccentric configuration can be beneficial, for example, to create a whipping motion to clean large open areas near the entrance to the root canal. Alternatively or additionally, the file can have a serpentine geometry (e.g., as shown in FIG. 28B). For example, the serpentine configuration can include curvatures throughout all and / or a majority of the length of the file (e.g., greater than 10%, and / or 10-25%, and / or 25-50%, and / or 50-75%, and / or 5-10%, and / or 2-5% of the file can be curved at rest). The serpentine geometry can facilitate elastic buckling of the file under axial pressure (e.g., as the dentist forces the file into the channel). The elasticity and / or buckling of the file can cushion axial forces and limit the force exerted on the distal point of the file (e.g., preventing the distal end of the file from being pushed out of the root canal and into the sensitive tissue surrounding the tooth). The buckling along the file can optionally push the file outward along its length filling the sides of the root canal. This can be particularly useful when cleaning the middle portion of the root canal (e.g., between the apex and the lateral portion). Optionally, the resilient curved structure of the serpentine file also redistributes forces, so that a portion of a high local lateral force that presses against the wall at one location, causing buckling, is distributed along the file, causing buckling at another location, preventing very large concentrated local forces from damaging and / or impacting the root canal wall.Optionally, the radius of curvature of the curved portion of the file body, in the rest state, can be in the ranges of 1-3 mm, and / or 3-10 mm, and / or 10-30 mm, and / or 30-50 mm, and / or 50-100 mm, and / or 100-300 mm. Optionally, the file can be sufficiently flexible to elastically buckle to a radius of curvature in the ranges of 0.2-1 mm, and / or 1-2 mm, and / or 2-4 mm, and / or 4-8 mm, and / or 8-16 mm.

[0161] 29 is a block diagram of a curved file, according to an embodiment of the present invention. In some embodiments, the endodontic file includes a proximal handle 2902 configured to fit, for example, into a dental handpiece. Optionally, the file includes a curved body 2904. For example, the curve of the body 2904 may be serpentine and / or eccentric. Optionally, the body may include a core and / or a helical winding, for example, as described in previous embodiments herein. For example, the core may include a multi-strand cable, and / or the helical winding may cover the core, and / or may include a wire, and / or may include a rough coating. Optionally, a distal portion of the file may be configured to form a brush 2911. For example, the brush 2911 may be formed by a distal portion of the core cable extending distally beyond the helical winding.

[0162] FIG. 30 is a flowchart illustrating a method for cleaning a root canal, according to an embodiment of the present invention. In some embodiments, a curved, flexible file (e.g., as described in the preceding embodiments) can be provided 3001. The handle of the file is optionally attached to a dental handpiece 3002. A distal brush of the file can be inserted into the apical portion of the root canal 3006. Optionally, the handle and / or file are rotated by the handpiece 3003, and / or the rotating file can simultaneously clean the apical portion of the root canal and / or the middle and / or lateral portions of the root canal 3008. For example, the brush of the file can open at the apex to scrape the root canal walls and / or cause turbulence in the disinfecting fluid. For example, the curved body of the file can whip and / or buckle within the lateral portion of the root canal to scrape the root canal walls and / or cause turbulence in the disinfecting fluid. For example, the file may be inserted while rotating in a first direction 3006, and / or the direction of rotation may be reversed to open the strands at the distal end of the file to form a brush and / or clean the sides of the root canal 3008. Optionally, an axial force may be applied to buckle the file and clean the sides of the outer portion of the root canal 3008.

[0163] 31 is a flowchart illustrating a two-stage method of root canal cleaning, according to an embodiment of the present invention. In some embodiments, an eccentric file (e.g., as described in the preceding embodiments) may be used for rough cleaning 3108 of the root canal, for example, the eccentricity of the file may enhance whipping and / or cleaning within the large opening on the exterior of the root canal 3108. Optionally, the eccentric file may include a brush to clean the apex of the root canal 3108. Optionally, the lateral and / or apical portions may be cleaned simultaneously 3108. Optionally, a serpentine file (e.g., as described in the preceding embodiments) may be used to further clean the root canal 3109. For example, the flexible buckling portion of the serpentine file may be beneficial for cleaning the middle portion of the root canal (between the exterior and the apex) 3109. Optionally, the serpentine file may include a brush to clean the apex of the root canal 3109. Optionally, the middle and / or apical portions may be cleaned simultaneously 3109.

[0164] FIG. 32 illustrates a method of cleaning a channel, according to one embodiment of the present invention. The inventors have observed that in some cases, counter-rotation can cause damage to the root canal. For example, rotating the outer winding against the winding direction of the outer winding can cause the stiff wire of the outer winding to protrude and / or cause damage to the root canal. In some embodiments, the brush and / or file can be used without counter-rotation. For example, the brush can be inserted without rotation 3206. Optionally, once the file is in place with the brush in the apex of the root canal, the brush can be rotated in the opposite direction of the winding 3203. For example, the brush can be twisted in the opposite direction to the twist of the outer winding. Alternatively or additionally, the brush can be twisted in a similar direction to the twist of the outer winding. For example, this can open the brush to clean the apex of the root canal without opening the outer winding. Optionally, the sides of the outer winding can be roughened, and / or the instrument can be off-centered and / or bent, for example, to clean the proximal walls of the root canal. For example, the brush and / or sides of the outer winding can clean the root canal during rotation and / or retraction 3205 from the root canal.

[0165] FIG. 33 illustrates a method of cleaning a channel, according to one embodiment of the present invention. For example, the brush can be inserted 3303 while rotating in the opposite direction of the brush windings. Alternatively or additionally, the brush can be twisted in a similar direction to the twist of the outer winding. For example, the brush can be twisted in the opposite direction of the twist of the outer winding. In some embodiments, the brush and / or file can be used without counter-rotation. For example, the brush can be flexible enough to enter the apex of the root canal even when opening and / or rotating in the opposite direction of twist 3306. For example, the brush can be twisted in the opposite direction of the twist of the outer winding. For example, this allows the brush to open without opening the outer winding to clean the apex of the root canal. Optionally, the sides of the outer winding can be roughened, and / or the instrument can be eccentric and / or curved, for example, to clean the proximal walls of the root canal. For example, the brush and / or sides of the outer winding may clean the root canal during rotation 3303 and / or retraction 3205 from and / or insertion 3306 into the root canal.

[0166] 34 illustrates a method of manufacturing an endodontic brush and / or file, according to an embodiment of the present invention. For example, a core can be provided 3408 and / or twisted in a torsional direction (optionally, the core can include a cable with all strands twisted in a single direction and / or a complex cable with strands twisted in various directions, e.g., the twist direction of the core is the twist direction of the innermost twisted strand). Optionally, an outer winding is wound 3409 around the core in the same twist direction of the core.

[0167] 35 illustrates a method of manufacturing an endodontic brush and / or file, according to an embodiment of the present invention. For example, a core can be provided 3408 and / or twisted in a torsional direction (optionally, the core can include a cable in which all strands are twisted in a single direction and / or a complex cable in which strands are twisted in various directions, e.g., the twist direction of the core is the twist direction of the innermost twisted strand). Optionally, an outer winding is wound 3509 around the core in a direction opposite to the twist direction of the core.

[0168] It is anticipated that many related technologies will be developed during the life of the patent resulting from this application, and the scope of the terms relating to design elements, analysis routines, and user devices is intended a priori to include all such new technologies.

[0169] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of this invention, exemplary methods and materials are described below. In the case of conflict, the patent specification, including definitions, will control. Additionally, the materials, methods, and examples are merely illustrative and are not intended to be necessarily limiting.

[0170] As used herein, the term "about" refers to ±10%.

[0171] The terms "comprises," "comprising," "includes," "including," "having," and their conjugations mean "including, but not limited to."

[0172] The term "consisting of" means "including but not limited to."

[0173] The term "consisting essentially of" means that a composition, method, or structure may include additional ingredients, steps, and / or parts so long as the additional ingredients, steps, and / or parts do not materially alter the basic and novel characteristics of the claimed composition, method, or structure.

[0174] As used herein, the singular forms "a," "an," and "the" include plural forms unless the context clearly indicates otherwise.

[0175] Throughout this application, various embodiments of the present invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Thus, the description of a range should be considered to include all possible subranges specifically disclosed as well as individual numerical values ​​within the range. For example, a description of a range such as 1 to 6 should be considered to include individual numbers within the range, such as 1, 2, 3, 4, 5, and 6, as well as specifically disclosed subranges such as 1 to 3, 1 to 4, 1 to 5, 2 to 4, 2 to 6, and 3 to 6. This applies regardless of the size of the range.

[0176] Whenever a range of values ​​is given herein, it is meant to include all numbers (fractions or integers) within the given range. The phrases "ranging across / between a first denoted number and a second denoted number" and "ranging from a first denoted number to a second denoted number" are used interchangeably herein and are meant to include the first and second denoted numbers and all fractions and integers therebetween. When multiple ranges are listed for a single variable, combined ranges are also included (e.g., the ranges 1 to 2 and / or 2 to 4 also include the combined ranges of 1 to 4).

[0177] It will be understood that certain features of the invention that are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination, or in any other described embodiment of the invention, as appropriate. Certain features described in the context of various embodiments are not to be regarded as essential features of those embodiments, unless the embodiment is impossible without those elements.

[0178] While the present invention has been described in conjunction with specific embodiments, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

[0179] All publications, patents, and patent applications mentioned in this specification are specifically and individually indicated to be incorporated by reference in their entirety as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference herein. Furthermore, citation or identification of a reference in this application should not be construed as an admission that it is available as prior art to the present invention. To the extent that section headings are used, they should not be construed as necessarily limiting.

Claims

1. 1. A method of producing a kit, the method comprising:

1. Providing an endodontic brush, said endodontic brush comprising: a proximal handle configured to couple to the handpiece for rotation about the axis of rotation; An active part, an active portion formed by: winding a plurality of strands in a winding direction to form a central longitudinal flexible core, a distal portion of the central longitudinal flexible core being unbonded so that, during use, when the endodontic brush is rotated in a direction opposite to the winding direction, the plurality of strands unwind and open to form the endodontic brush; and helically winding a helical wire at least partially surrounding the central longitudinal flexible core and extending toward the distal portion of the central longitudinal flexible core, the unbonded portion of the central longitudinal flexible core protruding beyond the helical wire at the distal portion; The active portion includes a distal active portion, wherein a radial distance between the rotation axis of the proximal handle and a stress-free local center of mass of the distal active portion of the helical wire is greater than a radius of the proximal handle, a concentric portion connected to the proximal handle, and a transition section connecting the concentric portion and the distal active portion. providing said endodontic brush; and packaging the endodontic brush in a sterile, sterility-maintaining package.

2. The method of claim 1 , wherein wrapping the plurality of strands encircles an inner central flexible cable.

3. The method of claim 1 , wherein said providing further comprises non-uniformly cutting said tips along lines oriented at an acute angle relative to an axis of said central longitudinal flexible core.

4. The method of claim 3, wherein said cutting is along a line oriented at an acute angle of between 10 and 80 degrees relative to the axis of said central longitudinal flexible core.

5. The method of claim 3, wherein the cutting is along a line oriented at an acute angle of between 25 and 75 degrees relative to the axis of the central longitudinal flexible core.

6. The method of claim 3 , wherein the cutting is by an abrasive cutter.

7. The method of claim 3 , wherein the cutting is by a laser cutter.

8. The method of claim 3 , wherein the cutting is with an electrical discharge machining (EDM) cutter.

9. The method of claim 1 , wherein a proximal portion of the central longitudinal flexible core is bent within the proximal handle.

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