ENDODONTIC FILE FOR DENTAL ENDODONTIC TREATMENT

Abstract

The present invention provides an endodontic file (100) for treatment of a dental nerve, the endodontic file including a head part (10) inserted into and removably coupled to a rotary power tool; a tissue removing blade part (30) inserted into a root canal of a patient and removing diseased tooth nerves; and a stress dispersing part (20) composed of a plurality of helical coil spring rods (22) having the same inner diameter and central axis in the same section of a longitudinal direction thereof between the head part (10) and the tissue removing blade part (30). Accordingly, stress occurring due to rotation resistance produced while the tissue removing blade part of the endodontic file rotates in the root canal is prevented from being concentrated on the tissue removing blade part and fracture of the endodontic file is minimized.

Claims

1. An endodontic file (100) for treatment of a dental nerve, the endodontic file comprising: a head part (10); a tissue removing blade part (30) inserted into a root canal and removing diseased nerves; and a stress dispersing part (20) composed of a plurality of helical coil spring rods (22) having the same inner diameter and central axis in the same section of a longitudinal direction thereof between the head part (10) and the tissue removing blade part (30).

2. The endodontic file of claim 1, wherein the plurality of helical coil spring rods (22) are provided by being spirally cut through the central axis of rotation of the endodontic file (100) therealong in the longitudinal direction of the endodontic file (100).

3. The endodontic file of claim 2, wherein the plurality of helical coil spring rods (22) constitute a plurality of coil springs having the same inner diameter and central axis respectively, wherein the plurality of coil springs have the plurality of coil spring rods alternately positioned from each other in upward and downward directions by having another coil spring rod positioned between an upper position and a lower position of a coil spring rod.

4. The endodontic file of claim 2, wherein the plurality of helical coil spring rods (22) are positioned to face each other, with a horizontal through hole (152) passing through the central axis of rotation of the endodontic file (100) arranged therebetween.

5. The endodontic file of claim 1, wherein a cross section of the tissue removing blade part (30) is configured to have a triangular or rectangular shape.

6. The endodontic file of claim 1, wherein the coil spring rods (22) are formed by being cut in such a manner that a cutting part (s) having a linear shape of a processing machine such as a wire discharge cutting machine or a laser cutting machine is positioned to pass through a portion to become a central axis perpendicular to an inner diameter of a coil spring from an outer surface of a predetermined portion between the head part (10) and the tissue removing blade part (30) of the endodontic file (100) and to pass through an outer surface of a side contrary to a side of the outer surface, and one or both of the endodontic file (100) and the cutting part (s) are rotated and, at the same time, the one or both of the endodontic file (100) and the cutting part (s) are moved forward or backward along the portion to become the central axis perpendicular to the inner diameter of the coil spring.

7. The endodontic file of claim 6, wherein the central axis of rotation of the endodontic file (100) or the cutting part (s) has the same central axis as the central axis perpendicular to the inner diameter of each of the helical coil spring rods (22).

8. The endodontic file of claim 6, wherein two helical coil spring rods are provided by using the wire discharge cutting machine or the laser cutting machine and two helical coil spring rods are further provided by using the wire discharge cutting machine so as to have a structure having four helical coil spring rods.

9. The endodontic file of claim 1, wherein the coil spring rods (22) are provided by being helically cut from an outer surface of the endodontic file to a through hole along the longitudinal direction of the endodontic file (100) after the through hole is provided at the central axis of the endodontic file (100) in the longitudinal direction thereof.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description when taken in conjunction with the accompanying drawings, in which:

[0031] FIG. 1 is a perspective view illustrating a structure of an endodontic file according to a first embodiment of the present invention, wherein a stress dispersing part is provided between a head part and a tissue removing blade part;

[0032] FIG. 2 is a cut-away perspective view illustrating cut surfaces formed by cutting the stress dispersing part of FIG. 1;

[0033] FIG. 3 is a perspective view illustrating a structure of an endodontic file according to a second embodiment of the present invention, wherein a stress dispersing part is provided between the head part and the tissue removing blade part;

[0034] FIG. 4 is a cut-away perspective view illustrating cut surfaces formed by cutting the stress dispersing part of FIG. 3; and

[0035] FIG. 5 is a perspective view illustrating a method of processing the stress dispersing part having helical coil spring rods in the endodontic file according to the present invention.

BEST MODE

[0036] Hereinbelow, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0037] As illustrated in FIG. 1, an endodontic file 100 for treatment of a dental nerve according to the present invention includes a head part 10 inserted into and removably coupled to a rotary power tool; a tissue removing blade part 30 inserted into a root canal of a patient and removing diseased tooth nerves; and a stress dispersing part 20 composed of a plurality of helical coil spring rods 22 having the same inner diameter and central axis in the same section of a longitudinal direction thereof between the head part 10 and the tissue removing blade part 30.

[0038] Referring to FIGS. 1 and 2, the stress dispersing part 20 includes the plurality of helical coil spring rods provided in a connection part between the head part 10 and the tissue removing blade part 30. The plurality of helical coil spring rods are provided by being spirally cut through the central axis of rotation of the endodontic file therealong in the longitudinal direction of the endodontic file. Accordingly, the stress dispersing part 20 is configured to have the horizontal through holes spirally formed along a longitudinal direction of the endodontic file.

[0039] Referring to FIGS. 1 and 2, the stress dispersing part 20 may be provided between the head part 10 and the tissue removing blade part 30 and have two helical coil spring rods. Referring to FIG. 2, a cross section of the stress dispersing part 20 is divided into two cross sections. Meanwhile, referring to FIGS. 3 and 4, the stress dispersing part 20 may be provided between the head part and the tissue removing blade part and have four helical coil spring rods 22. Referring to FIG. 4, a cross section of the stress dispersing part 20 is divided in four cross sections. Accordingly, it is obvious that the helical coil spring rods maybe formed in plural.

[0040] Referring to FIG. 2, the plurality of helical coil spring rods 22 constitute a plurality of coil springs having the same inner diameter and central axis respectively, wherein the plurality of coil springs have the plurality of coil spring rods alternately positioned from each other in upward and downward directions by having another coil spring rod positioned between an upper position and a lower position of a coil spring rod. Furthermore, the plurality of helical coil spring rods 22 are positioned to face each other, with each of the horizontal through holes passing through the central axis of rotation of the endodontic file arranged therebetween. Preferably, the helical coil spring rods are configured to have a shape wound at an angle of at least 1080.

[0041] When the excessive resistance is applied to the rotating tissue removing blade part of the endodontic file while the endodontic file removes diseased tooth tissues while being rotated by the rotational force of the power tool, such a stress dispersing part 20 absorbs a certain amount of stress and prevents stress from being concentrated on the tissue removing blade part. That is, the coil spring rods absorb a certain amount of stress while the helical coil spring rods formed at an upper portion of the tissue removing blade part are wound when the excessive resistance is applied to the rotating tissue removing blade part of the endodontic file during the treatment. Accordingly, magnitude of the stress which may be concentrated on the tissue removing blade part is reduced.

[0042] In addition, when excessive rotation resistance is applied to the tissue removing blade part, the stress dispersing part 20 delays immediate generation of stress on the tissue removing blade part in such a manner that the coil spring rods are wound, and allows the tissue removing blade part to take time and push tooth tissues at a relatively slow speed while rotating. Consequently, impact directly applied to the tissue removing blade part is buffered and the possibility of the fracture of the tissue removing blade part of the endodontic file is considerably decreased.

[0043] Furthermore, due to the winding of coil springs of the stress dispersing part 20 occurring when the excessive rotation resistance is applied to the tissue removing blade part during treatment and unusual feeling and sounds perceived during the winding of the coil springs, a clinician can detect that excessive resistance is applied to the tissue removing blade part and take steps prior to the fracture of the tissue removing blade part. Accordingly, excellent stability is obtained during the dental nerve treatment performed by the endodontic file.

[0044] Meanwhile, the stress dispersing part composed of the plurality of coil spring rods has a structure of the plurality of coil springs, so the connection part having the stress dispersing part may be easily bent at an angle of 90 or more due to a characteristic of the coil spring structure. Accordingly, a clinician can efficiently transfer the rotational force of the power tool to the tissue removing blade part of the endodontic file with the connection part of the endodontic file bent at an angle of about 90. Accordingly, comfortable treatment is possible although a patient does not open his or her mouth widely.

[0045] Preferably, as illustrated in a cross-sectional view taken along line A-A of FIG. 1, a cross section of the tissue removing blade part 30 may be configured to have a triangular or rectangular shape.

[0046] Although the tissue removing blade part of the endodontic file according to the present invention has any shape, the effects of the present invention can be achieved. The most effective structure of the tissue removing blade part in which the function of the stress dispersing part composed of the coil spring rods is maximized is a triangular structure having a tissue removal blade formed at every angle of 120 or a rectangular structure having a tissue removal blade formed at every angle of 90 when the tissue removing blade part is seen from the cross section thereof relative to the longitudinal direction of the endodontic file.

[0047] This is because the coil spring rods absorb a certain amount of stress and time reaching a maximum value of the rotation resistance is delayed while the coil spring rods of the stress dispersing part provided at an upper portion of the tissue removing blade part are wound when the rotation resistance is applied to the tissue removing blade part having such a cross section having a triangular or a rectangular shape in the root canal. In this case, capability of the coil spring rods restored by elastic force after being wound in the longitudinal direction is excellent, so a situation in which the rotation resistance is applied to the tissue removing blade part can be overcome most effectively.

[0048] A method of machining the coil spring rods 22 constituting the stress dispersing part 20 of the present invention will be described hereinbelow.

[0049] First, a cutting part s having a linear shape of a processing machine such as a wire discharge cutting machine or a laser cutting machine is positioned to pass through a portion to become a central axis perpendicular to an inner diameter of a coil spring from an outer surface of a predetermined portion between the head part and the tissue removing blade part of the endodontic file and to pass through an outer surface of a side contrary to a side of the outer surface. Next, the coil spring rods are cut while one or both of the endodontic file and the cutting part s are rotated and, at the same time, the one or both of the endodontic file and the cutting part s are moved forward or backward along the portion to become the central axis perpendicular to the inner diameter of the coil spring. Accordingly, the stress dispersing part composed of the helical coil spring rods may be formed. The central axis of rotation of the endodontic file or the cutting part s has the same central axis as the central axis perpendicular to the inner diameter of each of the helical coil spring rods. For reference, FIG. 5 illustrates an example of machining the coil spring rods in such a manner that the head part is moved backward at the same time when the endodontic file is rotated, with the cutting part s fixed. As illustrated in FIGS. 2 and 4, spiral cut parts 24 are formed between the coil spring rods machined in such a manner.

[0050] Meanwhile, as illustrated in FIGS. 3 and 4, in forming the stress dispersing part 20 composed of four helical coil spring rods, first, two helical coil spring rods are provided by using the wire discharge cutting machine or the laser cutting machine in the above-mentioned processing method, and then two coil spring rods are further provided by using the wire discharge cutting machine. Finally, four helical coil spring rods may be formed. Considering productivity, it is ideal to form four coil spring rods at a time by using a laser cutting machine. This is because when two helical coil spring rods are machined and then the remaining two helical coil spring rods are machined by the laser cutting machine, welding occurs during the second laser cutting, so performance and function of the coil spring rods deteriorate.

[0051] Preferably, the number of the coil spring rods may be differently provided at every portion between the head part and the tissue removing blade part. That is, four coil spring rods may be provided at a portion adjacent to the head part and two coil spring rods may be provided at a portion adjacent to the tissue removing blade part. Accordingly, the number of the coil spring rods may vary according to a portion between the head part and the tissue removing blade part.

[0052] Meanwhile, the coil spring rods may be provided by being helically cut from an outer surface of the endodontic file to a through hole along the longitudinal direction of the endodontic file after the through hole is provided at the central axis of the endodontic file in the longitudinal direction thereof.

[0053] Although the preferred embodiments of the present invention has been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. For example, the cross-sectional shape and the number of the horizontal through hole 152 may vary while exhibiting the same effect. However, it is intended that such simple modifications or variations be made within the scope of the present invention.