WO2021033777A1 - Dental root canal treatment instrument - Google Patents

Dental root canal treatment instrument Download PDF

Info

Publication number
WO2021033777A1
WO2021033777A1 PCT/JP2020/031724 JP2020031724W WO2021033777A1 WO 2021033777 A1 WO2021033777 A1 WO 2021033777A1 JP 2020031724 W JP2020031724 W JP 2020031724W WO 2021033777 A1 WO2021033777 A1 WO 2021033777A1
Authority
WO
WIPO (PCT)
Prior art keywords
long
continuous
tip
diagonal line
cross
Prior art date
Application number
PCT/JP2020/031724
Other languages
French (fr)
Japanese (ja)
Inventor
和彦 松谷
勝一 黒子
鈴木　大介
岡田　智弘
諭 古川
Original Assignee
マニー株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by マニー株式会社 filed Critical マニー株式会社
Publication of WO2021033777A1 publication Critical patent/WO2021033777A1/en

Links

Images

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C5/00—Filling or capping teeth
    • A61C5/40—Implements for surgical treatment of the roots or nerves of the teeth; Nerve needles; Methods or instruments for medication of the roots
    • A61C5/42—Files for root canals; Handgrips or guiding means therefor

Definitions

  • the present invention relates to a root canal treatment instrument having a spiral cutting edge used when forming a root canal in dental treatment.
  • the root canal of the tooth has an extremely thin tip and a slightly bent shape as a whole. And this shape has a large individual difference.
  • a bent root canal wall is cut and formed into a tapered shape.
  • Such root canal molding is performed using a root canal treatment instrument with a spiral cutting edge called a file, a reamer.
  • the root canal is formed by pinching the file or reamer selected by the doctor with the fingertips and rotating or pushing and pulling.
  • the selected root canal treatment instrument is often held by a chuck of a rotation driving instrument called a handpiece, and the root canal treatment is performed while rotating in this state.
  • the root canal treatment instrument is configured to have a handle and a cutting member fixed to the handle.
  • the handle has an optimum shape depending on whether it is gripped and operated by a doctor or held and operated by a handpiece.
  • the cutting member has a shaft portion fixed to the handle and a working portion continuous with the shaft portion, and the working portion is formed in a tapered shape.
  • Root canal treatment instruments are required to have good cutting performance on the root canal wall, good removal performance of cutting debris, and flexible follow-up performance on the root canal. Further, when treating the root canal, it is required that the tip portion of the root canal treatment instrument does not bite into the tip portion of the root canal, making the operation difficult or breaking. In order to meet such a demand, the root canal treatment instruments described in Patent Documents 1 and 2 have been proposed.
  • the invention described in Patent Document 1 relates to a root canal treatment instrument such as a file or a reamer, and can exhibit machinability only during a pulling operation without exhibiting machinability during a pushing operation. It is the one that was made.
  • This root canal treatment instrument has a parallelogram whose long side has a length of 1.5 times or more the short side, and has two edges close to each other in the longitudinal direction of the working part. It is configured by arranging sharp edges on the shaft side.
  • the invention described in Patent Document 2 relates to a root canal treatment instrument such as a file or a reamer, and improves the flexibility of the original part in the working part.
  • the shape of the cross section of the working part is a parallelogram
  • the length of the long side / the length of the short side in the cross section of the base part on the shaft part side is the cross section of the tip part. It is formed to be larger than the length of the long side / the length of the short side in the above, and the twist angle on the base side is larger than the twist angle on the tip side.
  • Japanese Patent No. 421485 Japanese Patent Laid-Open No. 11-358917
  • Japanese Patent No. 4214286 Japanese Patent Laid-Open No. 2000-000481
  • the part where flexibility should be required may differ from the tip of the working part to the base side.
  • the tip of the working part may differ from the base side.
  • the initial stage of root canal treatment it is common to use a thin working part for penetration and preliminary enlargement, and if the tip of the working part is too flexible, it may hinder operability. Therefore, bending rigidity may be required for the tip portion, and flexibility may be required from the intermediate portion of the working portion to the shaft portion side. That is, it may be required that the flexural rigidity of the tip portion side is stronger than that of the shaft portion side without requiring uniform flexibility from the shaft portion side to the tip portion side.
  • An object of the present invention is to provide a dental root canal treatment instrument capable of exhibiting flexibility different from that of the shaft portion in a desired range from the tip end side to the shaft portion side of the working portion.
  • the first dental root canal treatment instrument has a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion.
  • the working portion is formed in a tapered shape that narrows from the transition portion to the tip, and the cross section of the working portion on the most shaft portion side is a pair of long sides facing each other and a pair of short sides facing each other. It is a parallel quadrilateral having a side, a sharp edge formed on a long diagonal line, and a blunt angle edge formed on a short diagonal line, and the cross section near the tip of the working portion is a pair of the above-mentioned lengths.
  • the second dental root canal treatment instrument is a dental root canal treatment instrument having a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion.
  • the working part is formed in a tapered shape that narrows from the transition part to the tip, and the cross section of the working part on the most shaft part side is a pair of long sides facing each other, a pair of short sides facing each other, and a long diagonal line. It is a parallel quadrilateral having a sharp edge formed on the top and a blunt edge formed on a short diagonal line, and the cross section near the tip of the working portion is a pair of sides continuous from the long side.
  • a pair of sides continuous from the short side, a sharp edge continuous from the sharp edge formed on a long diagonal, and a blunt edge continuous from the blunt edge formed on a short diagonal It is a parallel quadrilateral having, and the angle formed by the long diagonal line and the side continuous from the long side near the tip is larger than the angle formed by the long side and the long diagonal line on the shaft portion side, and the working portion has.
  • the angle formed by the long side of the parallel quadrilateral in the cross section on the tip side from the predetermined position and the long diagonal line shall be fixed at the same angle as the angle formed by the long diagonal line and the continuous side from the long side near the tip end. It is characterized by.
  • the third dental root canal treatment instrument is a dental root canal treatment instrument having a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion.
  • the working portion is formed in a tapered shape that narrows from the transition portion to the tip, and the cross section of the working portion on the most shaft portion side is a pair of long sides facing each other, a pair of short sides facing each other, and a long diagonal line. It is a parallel quadrilateral having a sharp edge formed on the surface and an blunt edge formed on a short diagonal line, and the cross section near the tip of the working portion is a pair of sides continuous from the long side.
  • the angle formed by the long diagonal line and the continuous side from the long side near the tip is larger than the angle formed by the long side and the long diagonal line on the shaft portion side, and the predetermined working portion is defined.
  • the angle formed by the long side of the parallel quadrilateral in the cross section on the shaft portion side from the position and the long diagonal line is fixed at the same angle as the angle formed by the long side and the long diagonal line on the most shaft portion side. Is to be.
  • the dental root canal treatment instrument has a shaft portion, a transition portion continuous with the shaft portion, and a working portion having a parallelogram cross-sectional shape continuous with the transition portion.
  • the working unit has a fixed side ratio region in which the side ratio of the long side and the short side of the cross section is fixed, and a variable side ratio region in which the side ratio of the long side and the short side changes. You may have.
  • the side ratio fixed region may be provided on the tip side of the working portion and the side ratio variable region may be provided on the shaft portion side of the working portion.
  • the side ratio fixed region may be provided on the shaft portion of the working portion. It may be provided on the portion side and the side ratio variable region may be provided on the tip end side of the working portion.
  • the dental root canal treatment instrument according to the present invention (hereinafter, simply referred to as “root canal treatment instrument”) can exhibit different flexibility on the tip side and the shaft portion side from a predetermined position of the working portion.
  • the cross section near the shaft portion and the vicinity of the tip of the working portion are parallelograms, respectively, and the angle formed by the long side and the long diagonal in the cross section near the tip is It is larger than the angle formed by the long side and the long diagonal in the cross section near the shaft portion.
  • the rake angle formed on the long diagonal line near the tip is smaller than the rake angle formed on the long diagonal line near the shaft portion.
  • the flexibility of the vicinity of the tip of the working portion is reduced as compared with that of the vicinity of the shaft portion, and it becomes difficult to bend.
  • the torsional strength can be increased and the large rotational force of the handpiece can be transmitted.
  • the cross section near the shaft portion and the vicinity of the tip of the working portion are parallelograms, respectively, and the long side of the parallelogram of the cross section on the tip side from the predetermined position of the working portion.
  • the angle formed by the long diagonal line is fixed at the same angle as the angle formed by the long diagonal line and the continuous side from the long side near the tip.
  • the rake angle formed on the long diagonal line becomes smaller than the rake angle formed on the long diagonal line near the shaft portion, and as a result, from the vicinity of the tip to the predetermined position.
  • the bending rigidity of the range can be increased.
  • the torsional strength in the range from the vicinity of the tip of the working portion to the predetermined position can be increased to transmit a large rotational force of the handpiece.
  • the cross section near the shaft portion and the vicinity of the tip of the working portion are parallelograms, respectively, and the long side of the parallelogram of the cross section on the shaft portion side from the predetermined position of the working portion.
  • the angle formed by the long diagonal line is fixed at the same angle as the angle formed by the long side on the shaft portion side and the long diagonal line.
  • the rake angle formed on the long diagonal line near the tip is smaller than the rake angle formed on the long diagonal line near the shaft portion, and the rake angle near the shaft portion is smaller in the range from the predetermined position toward the vicinity of the shaft portion. Is equal to.
  • the flexural rigidity near the tip can be made higher than that near the shaft, and can be changed so as to be substantially the same as the shaft side within the range from the vicinity of the tip to a predetermined position toward the shaft side. it can.
  • the torsional strength can be increased to transmit a large rotational force of the handpiece.
  • the root canal treatment instrument according to the present invention has a shaft portion, a transition portion continuous with the shaft portion, and a tapered working portion continuous with the transition portion, and is a target for dental treatment. This is for forming the root canal into a tapered shape.
  • the root canal treatment instrument according to the present invention has a shaft portion, a transition portion continuous with the shaft portion, and a tapered working portion continuous with the transition portion, and is a target for dental treatment. This is for forming the root canal into a tapered shape.
  • the flexural rigidity near the tip of the working part and the bending rigidity near the shaft part it is possible to delicately cut the tip part of the root canal during the initial molding of the root canal and the molding of the tip part. Moreover, it is possible to prevent the root canal from biting into the wall.
  • the torsional strength is increased and it is possible to transmit a large rotational force by the handpiece. is there.
  • the working part is formed in a tapered shape that narrows from the transition part to the tip.
  • the taper of the working part is standardized as 2/100 in ISO.
  • the taper is not necessarily limited to the taper, and it is preferable that the optimum taper is appropriately set according to the treatment site.
  • the thickness of the working portion is set in the range of 0.06 mm to 1.40 mm at the tip portion of the working portion, and a plurality of types having different dimensions within this range are standardized.
  • the working portion is formed in a spiral shape and a gap is formed between the working portion and the adjacent edge when treating the root canal, it is possible to discharge cutting chips through this gap. ..
  • the root canal treatment instrument according to the present invention does not limit whether the treatment is performed by a doctor by grasping it or by attaching it to a handpiece. For this reason, the root canal treatment instrument is integrally molded with a synthetic resin handle so that the shaft portion can be grasped by a doctor, or a metal shank so that the shaft portion can be grasped by the chuck of the handpiece, according to the operation method. Is integrated into.
  • the cross section of the working portion on the most shaft portion side has a pair of long sides facing each other, a pair of short sides facing each other, and a sharp edge formed on a long diagonal line. It is formed as a parallelogram with obtuse edges formed on a short diagonal.
  • the cross section near the tip of the working portion includes a pair of sides continuous from the pair of long sides, a pair of sides continuous from the pair of short sides, and a long diagonal line continuous from the acute-angled edge. It is formed as a parallelogram with sharp edges.
  • the transition portion is a portion formed to smoothly connect a shaft portion having a circular cross section and a working portion having a parallelogram cross section, and has almost no cutting ability.
  • the long side and the long diagonal in the parallelogram that constitutes the cross section near the tip The angle between them is large. That is, the parallelogram forming the cross section near the tip is formed in a shape closer to a rectangle than the parallelogram forming the cross section near the shaft portion.
  • the angle formed by the long side and the long diagonal line in the cross section near the tip of the working portion is larger than the angle formed by the long side and the long diagonal line in the cross section near the shaft portion. That is, the rake angle becomes smaller near the tip. Therefore, when treating the root canal, it is possible to prevent the root canal from biting into the root canal wall in the vicinity of the tip. As a result, it becomes possible to easily follow the bending of the root canal and the like, and it becomes possible to perform treatment by an intended route.
  • the cross-sectional area near the tip of the working portion is larger than the case where the shape of the cross section near the tip is similar to the parallelogram constituting the cross section near the shaft portion. For this reason, it is possible to prevent breakage that may occur during treatment, and the flexural rigidity is increased to transmit a good reaction force to the doctor during treatment, or to reliably transmit the rotational force of the handpiece. Is possible.
  • the second root canal treatment instrument in the present invention sets a range from the tip of the working portion to a predetermined position, and the shape of the cross section within this range is similar to the cross section near the tip described above. It is a parallelogram with a cross section. Further, the third root canal treatment instrument is a parallelogram having a cross section near the tip and a parallelogram similar to the cross section near the shaft within a range from the vicinity of the tip of the working portion to a predetermined position. The angle formed by the long side and the long diagonal line is changed so as to be.
  • the vicinity of the tip of the working portion is preferably in the range of 0.5 mm to 1.0 mm from the tip of the working portion. However, it does not necessarily have to be in this range, and may be 0.5 mm to 1.5 mm or 0.5 mm to 2.0 mm.
  • the vicinity of the shaft portion is a predetermined range from the position on the most shaft portion side of the working portion, in other words, is formed between the working portion exhibiting good cutting performance and the working portion and the shaft portion. It is near the boundary part with the transition part that shifts from the working part to the shaft part. However, it does not necessarily have to be this boundary portion, and the length from the tip required for performing actual root canal treatment may be specified.
  • the dimension from the vicinity of the tip of the working part to the predetermined position toward the shaft part is not particularly limited, and is appropriately set according to the purpose of use of the target root canal treatment instrument and the thickness and length of the working part. It is preferable to do so. According to the findings of the present inventor, it was preferable that the predetermined position from the tip of the working part was in the range of about 10% to about 70% of the total length of the working part.
  • the material of the root canal treatment instrument is not limited, and austenitic stainless steel, martensitic stainless steel, titanium alloy having a shape memory function, and the like can be selectively used. Then, it is preferable to manufacture the target root canal treatment instrument by processing the selected material by the most suitable processing method.
  • a range of approximately 25% of the length of the working portion is set as a range from the tip of the working portion to a predetermined position, and the shape of the cross section within this range is set. It is a parallelogram consisting of a cross section similar to the cross section near the tip.
  • the root canal treatment instrument is configured to be attached to a handpiece and driven to rotate. Therefore, in the root canal treatment instrument, the shaft portion A, the transition portion D continuous with the shaft portion A, the working portion B continuous with the transition portion D, and the shaft portion A are fixed and gripped by the chuck of the handpiece. It is configured to have a shank portion C to be formed.
  • the shaft portion A to the working portion B are continuously formed from one material.
  • the shaft portion A is formed in a shaft shape, and the transition portion D and the working portion B are continuously formed on one side, and the other side is connected to the shank portion C and integrated.
  • the working portion B is formed in a tapered shape that narrows from the transition portion D side to the tip, and the working portion B has a shaft portion near Ba (cross section IIBa), a tip near tip Bb (cross section IIBb), and a predetermined length from near the tip.
  • a predetermined position Bc (cross section IIBc), which is a boundary on the shaft portion side of the range, is set respectively.
  • the cross section IIBa near the shaft and the cross section IIBb near the tip have different shapes. That is, as shown in FIG. 2A, the cross section IIBa at the position near the shaft portion is a parallelogram consisting of a pair of long sides 1a facing each other and a pair of short sides 2a facing each other, and a long diagonal line 3a. An acute-angled edge 5a is formed on the top, and an obtuse-angled edge 6a is formed on the short diagonal line 4a.
  • the angle ⁇ formed by the long side 1a and the long diagonal line 3a in the cross section IIBa is approximately 20 degrees in this embodiment, and is set to a negative rake angle.
  • the angle ⁇ is not limited to the above-mentioned angle, and may be larger or smaller than this angle.
  • the cross section IIBb at the position near the tip of the working portion B includes a pair of long sides 1a continuous from the pair of long sides 1a constituting the cross section IIBa near the shaft portion and a pair of sides 1b.
  • a pair of sides 2b continuous from a pair of opposite short sides 2a constituting the cross section IIBa, an edge 5b continuous from an acute-angled edge 5a on a long diagonal 3b, and an obtuse angle continuous from an obtuse edge 6a on a short diagonal 4b.
  • An edge 6b is formed.
  • the angle ⁇ formed by the long side 1b and the long diagonal line 3b in the cross section IIBb is set to be larger than the angle ⁇ formed by the long side 1a and the long diagonal line 3a in the cross section Ba near the shaft portion.
  • the angle ⁇ may be larger than the angle ⁇ and does not limit the numerical value.
  • the angle ⁇ is approximately 35 degrees and is set to a negative rake angle.
  • the rake angle in the cross section IIBb is smaller than the rake angle in the cross section IIBa.
  • the diameter of the inscribed circle (core) 8b of the cross section IIBb is larger than the diameter of the inscribed circle when the similar figure of the cross section IIBa near the shaft portion is taken as the cross section near the tip.
  • the rake angle with respect to the root canal wall is small near the tip of the working portion B, the cutting performance is lower than that near the shaft portion. Therefore, when treating the root canal, it is possible to prevent biting into the root canal wall. In addition, it is possible to increase the thickness of the core, increase the bending rigidity, and increase the torsional strength to transmit a sufficient rotational force.
  • the range from the vicinity of the tip of the working portion to the cross section IIBc of the predetermined position Bc has a cross-sectional shape similar to the cross-sectional shape of the cross section IIBb near the tip.
  • the cross section IIBb includes a pair of long sides 1c continuous from a pair of long sides 1a constituting the cross section IIBa in the vicinity of the shaft portion, and a pair of opposite short sides 2a constituting the cross section IIBa.
  • a pair of sides 2c continuous from the above, an acute-angled edge 5a to a continuous edge 5c on a long diagonal line 3c, and an obtuse-angled edge 6c continuous to an obtuse-angled edge 6a on a short diagonal line 4c are formed.
  • the angle formed by the long side 1c and the long diagonal line 3c in the cross section IIBc is the angle ⁇ formed by the long side 1a and the long diagonal line 3a in the cross section IIBa near the shaft portion, similarly to the cross section IIBb near the tip. It is set to a larger angle ⁇ . Therefore, the rake angle is smaller than the rake angle in the cross section IIBa. In addition, the diameter of the core of the cross section IIBc also increases.
  • the first The root canal treatment instrument has a fixed side ratio region from the predetermined position Bc to the tip side, and a variable side ratio region from the predetermined position Bc to the shaft portion side.
  • the change in shape from the cross section IIBa to the cross sections IIBb and IIBc as described above may be achieved by adjusting the amount of the abrasive material driven in when forming the working portion B in the case of grinding.
  • the shape of the cross section VBa in the vicinity of the shaft portion and the cross section VBb in the vicinity of the tip portion are the corresponding cross sections IIBa of the first embodiment described above, respectively, as shown in FIGS. 5A and 5B. Same as IIBb.
  • the shape of the cross section VBc on the shaft portion side from the predetermined position Bc of the working portion B has a similar shape to the cross section VBa in the vicinity of the shaft portion. That is, as shown in FIG. 5C, the cross section VBc is a parallelogram composed of a pair of long sides 1c facing each other and a pair of short sides 2c facing each other, and an acute-angled edge 5c is formed on a long diagonal line 3c. An obtuse edge 6c is formed on the short diagonal 4c.
  • the angle formed by the long side 1c and the long diagonal line 3c in the cross section VBc is set to the angle ⁇ formed by the long side 1a and the long diagonal line 3a in the cross section VBa near the shaft portion.
  • the cross-sectional shape changes from the cross section VBb near the tip to the cross section VBc at the predetermined position Bc. That is, the angle ⁇ formed by the long side 1b and the long diagonal line 3b is as long as the long side 1a in the cross section VBa near the shaft portion in the range from the vicinity of the tip of the working portion B to the predetermined position Bc toward the shaft portion side. It decreases so as to be equal to the angle ⁇ formed by the diagonal line 3a. Therefore, at the predetermined position Bc in the working portion B, the cross section VBc has a similar shape to the cross section VBa in the vicinity of the shaft portion.
  • the root canal treatment instrument according to the second embodiment has a fixed side ratio region from the predetermined position Bc to the shaft portion side, and a variable side ratio region from the predetermined position Bc to the tip side.
  • high bending rigidity is realized near the tip of the working portion B, and the bending rigidity can be reduced in the range from the vicinity of the tip to a predetermined position to approach the bending rigidity on the shaft portion side. Further, transmitting the rotational force of the handpiece is the same as that of the root canal treatment instrument according to the first embodiment described above.
  • the root canal treatment instrument according to the present invention can be used for root canal treatment in dental treatment.

Landscapes

  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Neurology (AREA)
  • Neurosurgery (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Surgery (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Dentistry (AREA)
  • Epidemiology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)

Abstract

The present invention is configured so that differing flexibility can be exhibited in a desired range from the distal end of an operating part to a shaft part side. The present invention has a shaft part (A) and an operating part (B), the operating part being formed in a tapered shape that narrows from the shaft part to the distal end of the operating part. A cross section (Ba) of the operating part farthest toward the shaft part is a parallelogram having a pair of opposing long sides (1a), a pair of opposing short sides (2a), acute-angled edges (5a) formed on a long diagonal (3a), and obtuse-angled edges (5a) formed on a short diagonal (4a). A cross section (IIBb) near the distal end of the operating part is a parallelogram having sides (1b) continuous from the pair of long sides (1a), sides (2b) continuous from the pair of short sides (2a), acute-angled edges (5b) which are formed on a long diagonal (3b) and are continuous from the acute-angled edges (5a), and obtuse-angled edges (6b) which are formed on a short diagonal (4b) and are continuous from the obtuse-angled edges (6a). The angle (β) formed by a side (1b) constituting the cross section (IIBb) and the long diagonal (3b) is larger than the angle (α) formed by a long side (1a) in a cross section (IIBa) and the long diagonal (3a).

Description

歯科用根管治療器具Dental root canal treatment instrument
　本発明は、歯科治療に際し根管を成形する際に用いる螺旋状の切刃を有する根管治療器具に関するものである。 The present invention relates to a root canal treatment instrument having a spiral cutting edge used when forming a root canal in dental treatment.
　歯の根管は先端部分が極めて細く、且つ全体が微妙に屈曲した形状を有している。そして、この形状は個人差が大きい。根管を治療する際には屈曲した根管壁を切削してテーパ状に成形することが行われる。このような根管の成形はファイル、リーマと呼ばれる螺旋状の切刃を有する根管治療器具を使用して行われる。 The root canal of the tooth has an extremely thin tip and a slightly bent shape as a whole. And this shape has a large individual difference. When treating a root canal, a bent root canal wall is cut and formed into a tapered shape. Such root canal molding is performed using a root canal treatment instrument with a spiral cutting edge called a file, a reamer.
　即ち、医師が選択したファイル或いはリーマを指先でつまんで回転操作し、或いは押し引き操作することで、根管の成形を行っている。最近では、選択された根管治療器具をハンドピースと呼ばれる回転駆動器具のチャックによって保持し、この状態で回転させながら根管の治療を行うことも多くなっている。 That is, the root canal is formed by pinching the file or reamer selected by the doctor with the fingertips and rotating or pushing and pulling. Recently, the selected root canal treatment instrument is often held by a chuck of a rotation driving instrument called a handpiece, and the root canal treatment is performed while rotating in this state.
　根管治療器具は、ハンドルと、該ハンドルに固定された切削部材とを有して構成されている。ハンドルは医師が把持して操作するか、或いはハンドピースに保持して操作するか、に対応させて最適な形状を有している。また、切削部材はハンドルに固定されるシャフト部と、該シャフト部と連続した作業部とを有しており、作業部はテーパ状に形成されている。 The root canal treatment instrument is configured to have a handle and a cutting member fixed to the handle. The handle has an optimum shape depending on whether it is gripped and operated by a doctor or held and operated by a handpiece. Further, the cutting member has a shaft portion fixed to the handle and a working portion continuous with the shaft portion, and the working portion is formed in a tapered shape.
　根管治療器具には、根管壁に対する良好な切削性能、切削屑の良好な排除性能、根管に対する柔軟な追従性能、などが要求される。また、根管を治療する際に、根管治療器具の先端部分が根管の先端部分に食い込んで操作が困難になるようなことや、破断するようなことがないという性能も要求される。このような要求に対応するために、特許文献１、２に記載された根管治療器具が提案されている。 Root canal treatment instruments are required to have good cutting performance on the root canal wall, good removal performance of cutting debris, and flexible follow-up performance on the root canal. Further, when treating the root canal, it is required that the tip portion of the root canal treatment instrument does not bite into the tip portion of the root canal, making the operation difficult or breaking. In order to meet such a demand, the root canal treatment instruments described in Patent Documents 1 and 2 have been proposed.
　特許文献１に記載された発明はファイル又はリーマなどの根管治療器具に関するものであり、押し操作の際には切削性を発揮することなく、引き操作の際にのみ切削性を発揮し得るようにしたものである。この根管治療器具は、作業部の横断面の形状が、長辺が短辺の１．５倍以上の長さを有する平行四辺形で、作業部の長手方向に近接した２つのエッジのうち鋭角のエッジをシャフト部側に配置して構成されている。 The invention described in Patent Document 1 relates to a root canal treatment instrument such as a file or a reamer, and can exhibit machinability only during a pulling operation without exhibiting machinability during a pushing operation. It is the one that was made. This root canal treatment instrument has a parallelogram whose long side has a length of 1.5 times or more the short side, and has two edges close to each other in the longitudinal direction of the working part. It is configured by arranging sharp edges on the shaft side.
　特許文献１に記載された根管治療器具では、作業部の横断面が平行四辺形として形成されているため、柔軟性を有しており屈曲した根管に対する良好な追従性を発揮することができる。また、医師が引き操作したときに切削性を発揮するため、切削屑の根管からの排出を容易に行うことが可能である。 In the root canal treatment instrument described in Patent Document 1, since the cross section of the working portion is formed as a parallelogram, it is flexible and can exhibit good followability to a bent root canal. it can. In addition, since the machinability is exhibited when the doctor pulls it, it is possible to easily discharge the cutting chips from the root canal.
　また、特許文献２に記載された発明はファイル又はリーマなどの根管治療器具に関するものであり、作業部に於ける元部の柔軟性を向上させたものである。この根管治療器具は、作業部の横断面の形状が平行四辺形で、且つシャフト部側の元部の横断面に於ける長辺の長さ／短辺の長さが先端部の横断面に於ける長辺の長さ／短辺の長さより大きく、元部側の捩じれ角が先端部の捩じれ角よりも大きく形成されている。 Further, the invention described in Patent Document 2 relates to a root canal treatment instrument such as a file or a reamer, and improves the flexibility of the original part in the working part. In this root tube treatment instrument, the shape of the cross section of the working part is a parallelogram, and the length of the long side / the length of the short side in the cross section of the base part on the shaft part side is the cross section of the tip part. It is formed to be larger than the length of the long side / the length of the short side in the above, and the twist angle on the base side is larger than the twist angle on the tip side.
　特許文献２に記載された根管治療器具では、平行四辺形の横断面に於ける長辺／短辺の長さを作業部の元部と先端部とで変化させたことによって、元部側の柔軟性を高めることができる。このため、操作性を向上させることができる。 In the root canal treatment instrument described in Patent Document 2, the length of the long side / short side in the cross section of the parallelogram is changed between the base portion and the tip portion of the working portion, so that the root portion side Can increase the flexibility of. Therefore, operability can be improved.
特許第４２１４２８５号公報（特開平１１－３５８９１７号）Japanese Patent No. 421485 (Japanese Patent Laid-Open No. 11-358917) 特許第４２１４２８６号公報（特開２０００－０００４８１号）Japanese Patent No. 4214286 (Japanese Patent Laid-Open No. 2000-000481)
　しかし、治療の段階や症例によっては、作業部の先端部分から元部側にかけて柔軟性を要求すべき部位が異なることがある。例えば、根管治療の初期段階に於ける穿通や予備拡大では作業部の細いものを利用するのが一般的であり、作業部の先端部分が柔軟すぎる場合、操作性を阻害するようなことがあるため、該先端部分に曲げ剛性が、作業部の中間部からシャフト部側で柔軟性が要求されることがある。即ち、シャフト部側から先端部側にかけて一様な柔軟性を要求することなく、先端部側の曲げ剛性をシャフト部側よりも強くすることを要求されることがある。 However, depending on the stage of treatment and the case, the part where flexibility should be required may differ from the tip of the working part to the base side. For example, in the initial stage of root canal treatment, it is common to use a thin working part for penetration and preliminary enlargement, and if the tip of the working part is too flexible, it may hinder operability. Therefore, bending rigidity may be required for the tip portion, and flexibility may be required from the intermediate portion of the working portion to the shaft portion side. That is, it may be required that the flexural rigidity of the tip portion side is stronger than that of the shaft portion side without requiring uniform flexibility from the shaft portion side to the tip portion side.
　また、ハンドピースによって回転駆動する根管治療器具では、作業部の先端部分まで確実に回転力を伝える必要がある。この場合、先端部分の捻じり強度を強くすることが要求される。 In addition, in a root canal treatment instrument that is rotationally driven by a handpiece, it is necessary to reliably transmit the rotational force to the tip of the working part. In this case, it is required to increase the torsional strength of the tip portion.
　上記の如く、治療部位や術式によって柔軟性を発揮すべき部位が異なる場合、特許文献１、２に記載された根管治療器具であっても、１本で要求に対応することが困難であるという問題がある。 As described above, when the site to be flexible differs depending on the treatment site and the surgical method, it is difficult to meet the demand with one root canal treatment instrument even with the root canal treatment instruments described in Patent Documents 1 and 2. There is a problem.
　本発明の目的は、作業部の先端部側からシャフト部側にかけての所望の範囲にシャフト部とは異なる柔軟性を発揮し得るようにした歯科用根管治療器具を提供することにある。 An object of the present invention is to provide a dental root canal treatment instrument capable of exhibiting flexibility different from that of the shaft portion in a desired range from the tip end side to the shaft portion side of the working portion.
　上記課題を解決するために本発明に係る第１の歯科用根管治療器具は、シャフト部と、シャフト部に連続した移行部と、移行部に連続した作業部と、を有する歯科用根管治療器具であって、作業部は移行部から先端にかけて細くなるテーパ状に形成されており、前記作業部の最もシャフト部側の横断面は、対向した一対の長辺と、対向した一対の短辺と、長い対角線上に形成された鋭角のエッジと、短い対角線上に形成された鈍角のエッジと、を有する平行四辺形であり、前記作業部の先端近傍の横断面は、一対の前記長辺から連続した辺と、一対の前記短辺から連続した辺と、長い対角線上に形成された前記鋭角のエッジから連続した鋭角のエッジと、短い対角線上に形成された前記鈍角のエッジから連続した鈍角のエッジと、を有する平行四辺形であり、先端近傍の前記長辺から連続した辺と長い対角線とのなす角がシャフト部側の前記長辺と長い対角線とのなす角よりも大きいことを特徴とするものである。 In order to solve the above problems, the first dental root canal treatment instrument according to the present invention has a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion. In the treatment instrument, the working portion is formed in a tapered shape that narrows from the transition portion to the tip, and the cross section of the working portion on the most shaft portion side is a pair of long sides facing each other and a pair of short sides facing each other. It is a parallel quadrilateral having a side, a sharp edge formed on a long diagonal line, and a blunt angle edge formed on a short diagonal line, and the cross section near the tip of the working portion is a pair of the above-mentioned lengths. A side continuous from a side, a pair of sides continuous from the short side, a sharp edge continuous from the sharp edge formed on a long diagonal, and a continuous edge from the blunt edge formed on a short diagonal. It is a parallel quadrilateral having a blunt edge, and the angle formed by the long diagonal line and the continuous side from the long side near the tip is larger than the angle formed by the long side and the long diagonal line on the shaft portion side. It is characterized by.
　また、本発明に係る第２の歯科用根管治療器具は、シャフト部と、シャフト部に連続した移行部と、移行部に連続した作業部と、を有する歯科用根管治療器具であって、作業部は移行部から先端にかけて細くなるテーパ状に形成されており、前記作業部の最もシャフト部側の横断面は、対向した一対の長辺と、対向した一対の短辺と、長い対角線上に形成された鋭角のエッジと、短い対角線上に形成された鈍角のエッジと、を有する平行四辺形であり、前記作業部の先端近傍の横断面は、一対の前記長辺から連続した辺と、一対の前記短辺から連続した辺と、長い対角線上に形成された前記鋭角のエッジから連続した鋭角のエッジと、短い対角線上に形成された前記鈍角のエッジから連続した鈍角のエッジと、を有する平行四辺形であり、先端近傍の前記長辺から連続した辺と長い対角線とのなす角がシャフト部側の前記長辺と長い対角線とのなす角よりも大きく、且つ前記作業部の所定位置から先端側の横断面の平行四辺形の長辺と長い対角線とのなす角は、先端近傍の前記長辺から連続した辺と長い対角線とのなす角と同じ角度で固定されていることを特徴とするものである。 The second dental root canal treatment instrument according to the present invention is a dental root canal treatment instrument having a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion. , The working part is formed in a tapered shape that narrows from the transition part to the tip, and the cross section of the working part on the most shaft part side is a pair of long sides facing each other, a pair of short sides facing each other, and a long diagonal line. It is a parallel quadrilateral having a sharp edge formed on the top and a blunt edge formed on a short diagonal line, and the cross section near the tip of the working portion is a pair of sides continuous from the long side. And a pair of sides continuous from the short side, a sharp edge continuous from the sharp edge formed on a long diagonal, and a blunt edge continuous from the blunt edge formed on a short diagonal. It is a parallel quadrilateral having, and the angle formed by the long diagonal line and the side continuous from the long side near the tip is larger than the angle formed by the long side and the long diagonal line on the shaft portion side, and the working portion has. The angle formed by the long side of the parallel quadrilateral in the cross section on the tip side from the predetermined position and the long diagonal line shall be fixed at the same angle as the angle formed by the long diagonal line and the continuous side from the long side near the tip end. It is characterized by.
　また本発明に係る第３の歯科用根管治療器具は、シャフト部と、シャフト部に連続した移行部と、移行部に連続した作業部と、を有する歯科用根管治療器具であって、作業部は移行部から先端にかけて細くなるテーパ状に形成されており、前記作業部の最もシャフト部側の横断面は、対向した一対の長辺と、対向した一対の短辺と、長い対角線上に形成された鋭角のエッジと、短い対角線上に形成された鈍角のエッジと、を有する平行四辺形であり、前記作業部の先端近傍の横断面は、一対の前記長辺から連続した辺と、一対の前記短辺から連続した辺と、長い対角線上に形成された前記鋭角のエッジから連続した鋭角のエッジと、短い対角線上に形成された前記鈍角のエッジから連続した鈍角のエッジと、を有する平行四辺形であり、先端近傍の前記長辺から連続した辺と長い対角線とのなす角がシャフト部側の前記長辺と長い対角線とのなす角よりも大きく、且つ前記作業部の所定位置からシャフト部側の横断面の平行四辺形の長辺と長い対角線とのなす角は、最もシャフト部側の前記長辺と長い対角線とのなす角と同じ角度で固定されていることを特徴とするものである。 Further, the third dental root canal treatment instrument according to the present invention is a dental root canal treatment instrument having a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion. The working portion is formed in a tapered shape that narrows from the transition portion to the tip, and the cross section of the working portion on the most shaft portion side is a pair of long sides facing each other, a pair of short sides facing each other, and a long diagonal line. It is a parallel quadrilateral having a sharp edge formed on the surface and an blunt edge formed on a short diagonal line, and the cross section near the tip of the working portion is a pair of sides continuous from the long side. , A pair of sides continuous from the short side, a sharp edge continuous from the sharp edge formed on a long diagonal, and a blunt edge continuous from the blunt edge formed on a short diagonal. The angle formed by the long diagonal line and the continuous side from the long side near the tip is larger than the angle formed by the long side and the long diagonal line on the shaft portion side, and the predetermined working portion is defined. The angle formed by the long side of the parallel quadrilateral in the cross section on the shaft portion side from the position and the long diagonal line is fixed at the same angle as the angle formed by the long side and the long diagonal line on the most shaft portion side. Is to be.
　また、本発明に係る歯科用根管治療器具は、シャフト部と、シャフト部に連続した移行部と、移行部に連続した横断面形状が平行四辺形の作業部と、を有する歯科用根管治療器具であって、作業部は、横断面の長辺と短辺の辺比が固定されている辺比固定領域と、長辺と短辺の辺比が変化する辺比可変領域と、を有することにしてもよい。 Further, the dental root canal treatment instrument according to the present invention has a shaft portion, a transition portion continuous with the shaft portion, and a working portion having a parallelogram cross-sectional shape continuous with the transition portion. In the treatment instrument, the working unit has a fixed side ratio region in which the side ratio of the long side and the short side of the cross section is fixed, and a variable side ratio region in which the side ratio of the long side and the short side changes. You may have.
　さらに、辺比固定領域が作業部の先端側に設けられ、辺比可変領域が作業部のシャフト部側に設けられていることにしてもよく、逆に、辺比固定領域が作業部のシャフト部側に設けられ、辺比可変領域が作業部の先端側に設けられていることにしてもよい。 Further, the side ratio fixed region may be provided on the tip side of the working portion and the side ratio variable region may be provided on the shaft portion side of the working portion. Conversely, the side ratio fixed region may be provided on the shaft portion of the working portion. It may be provided on the portion side and the side ratio variable region may be provided on the tip end side of the working portion.
　本発明に係る歯科用根管治療器具（以下単に「根管治療器具」という）では、作業部の所定位置から先端側とシャフト部側で、異なる柔軟性を発揮することができる。 The dental root canal treatment instrument according to the present invention (hereinafter, simply referred to as "root canal treatment instrument") can exhibit different flexibility on the tip side and the shaft portion side from a predetermined position of the working portion.
　即ち、第１の根管治療器具では、作業部のシャフト部近傍及び先端近傍の横断面は夫々平行四辺形であり、先端近傍の横断面に於ける長辺と長い対角線とのなす角が、シャフト部近傍の横断面に於ける長辺と長い対角線とのなす角よりも大きい。 That is, in the first root canal treatment instrument, the cross section near the shaft portion and the vicinity of the tip of the working portion are parallelograms, respectively, and the angle formed by the long side and the long diagonal in the cross section near the tip is It is larger than the angle formed by the long side and the long diagonal in the cross section near the shaft portion.
　このため、先端近傍では長い対角線上に形成されたすくい角がシャフト部近傍の長い対角線上に形成されたすくい角よりも小さくなる。この結果、作業部に於ける先端近傍がシャフト部近傍側よりも柔軟性が減少して曲がり難くなる。 Therefore, the rake angle formed on the long diagonal line near the tip is smaller than the rake angle formed on the long diagonal line near the shaft portion. As a result, the flexibility of the vicinity of the tip of the working portion is reduced as compared with that of the vicinity of the shaft portion, and it becomes difficult to bend.
　また、作業部の先端近傍の横断面に於ける平行四辺形の内接円の径を大きくすることで捻じり強さを大きくしてハンドピースの大きい回転力を伝えることができる。 Also, by increasing the diameter of the inscribed circle of the parallelogram in the cross section near the tip of the working part, the torsional strength can be increased and the large rotational force of the handpiece can be transmitted.
　また、第２の根管治療器具では、作業部のシャフト部近傍及び先端近傍の横断面は夫々平行四辺形であり、作業部の所定位置から先端側の横断面の平行四辺形の長辺と長い対角線とのなす角が先端近傍の長辺から連続した辺と長い対角線とのなす角と同じ角度で固定された構成になっている。 Further, in the second root tube treatment instrument, the cross section near the shaft portion and the vicinity of the tip of the working portion are parallelograms, respectively, and the long side of the parallelogram of the cross section on the tip side from the predetermined position of the working portion. The angle formed by the long diagonal line is fixed at the same angle as the angle formed by the long diagonal line and the continuous side from the long side near the tip.
　このように、先端近傍から所定位置までの範囲では、長い対角線上に形成されたすくい角がシャフト部近傍の長い対角線上に形成されたすくい角よりも小さくなる結果、先端近傍から所定位置までの範囲の曲げ剛性を高くすることができる。同様にして作業部の先端近傍から所定位置までの範囲の捻じり強さを大きくしてハンドピースの大きい回転力を伝えることができる。 In this way, in the range from the vicinity of the tip to the predetermined position, the rake angle formed on the long diagonal line becomes smaller than the rake angle formed on the long diagonal line near the shaft portion, and as a result, from the vicinity of the tip to the predetermined position. The bending rigidity of the range can be increased. Similarly, the torsional strength in the range from the vicinity of the tip of the working portion to the predetermined position can be increased to transmit a large rotational force of the handpiece.
　また、第３の根管治療器具では、作業部のシャフト部近傍及び先端近傍の横断面は夫々平行四辺形であり、作業部の所定位置からシャフト部側の横断面の平行四辺形の長辺と長い対角線とのなす角がシャフト部側の長辺と長い対角線とのなす角と同じ角度で固定された構成になっている。 Further, in the third root tube treatment instrument, the cross section near the shaft portion and the vicinity of the tip of the working portion are parallelograms, respectively, and the long side of the parallelogram of the cross section on the shaft portion side from the predetermined position of the working portion. The angle formed by the long diagonal line is fixed at the same angle as the angle formed by the long side on the shaft portion side and the long diagonal line.
　このため、先端近傍では長い対角線上に形成されたすくい角がシャフト部近傍の長い対角線上に形成されたすくい角よりも小さくなり、所定位置からシャフト部近傍に向かう範囲ではシャフト部近傍のすくい角と等しくなる。この結果、先端近傍の曲げ剛性をシャフト部近傍よりも高くすることができ、この先端近傍からシャフト部側に向かう所定位置までの範囲内でシャフト部側と略同じになるように変化させることができる。また、作業部の先端近傍では、捻じり強さを大きくしてハンドピースの大きい回転力を伝えることができる。 Therefore, the rake angle formed on the long diagonal line near the tip is smaller than the rake angle formed on the long diagonal line near the shaft portion, and the rake angle near the shaft portion is smaller in the range from the predetermined position toward the vicinity of the shaft portion. Is equal to. As a result, the flexural rigidity near the tip can be made higher than that near the shaft, and can be changed so as to be substantially the same as the shaft side within the range from the vicinity of the tip to a predetermined position toward the shaft side. it can. Further, in the vicinity of the tip of the working portion, the torsional strength can be increased to transmit a large rotational force of the handpiece.
第１実施例に係る根管治療器具の側面図である。It is a side view of the root canal treatment instrument which concerns on 1st Example. 第１実施例に係る作業部の横断面の形状を説明する拡大図である。It is an enlarged view explaining the shape of the cross section of the working part which concerns on 1st Example. 第１実施例に係る作業部を説明するための拡大斜視図である・It is an enlarged perspective view for explaining the working part which concerns on 1st Example. 第２実施例に係る根管治療器具の側面図である。It is a side view of the root canal treatment instrument which concerns on 2nd Example. 第２実施例に係る作業部の横断面の形状を説明する拡大図である。It is an enlarged view explaining the shape of the cross section of the working part which concerns on 2nd Example.
　以下、本発明に係る根管治療器具について説明する。本発明に係る根管治療器具は、シャフト部と、このシャフト部に連続した移行部と、この移行部に連続したテーパ状の作業部と、を有しており、歯科治療に際しては対象となる根管をテーパ状に成形するためのものである。特に、作業部の先端近傍の曲げ剛性とシャフト部近傍の曲げ剛性を変化させることによって、根管の初期成形や先端部分の成形に際し、根管の先端部分を繊細に切削することを可能とし、且つ根管壁への食い込みを防ぐことを可能としたものである。 Hereinafter, the root canal treatment instrument according to the present invention will be described. The root canal treatment instrument according to the present invention has a shaft portion, a transition portion continuous with the shaft portion, and a tapered working portion continuous with the transition portion, and is a target for dental treatment. This is for forming the root canal into a tapered shape. In particular, by changing the flexural rigidity near the tip of the working part and the bending rigidity near the shaft part, it is possible to delicately cut the tip part of the root canal during the initial molding of the root canal and the molding of the tip part. Moreover, it is possible to prevent the root canal from biting into the wall.
　更に、作業部の先端近傍の横断面に於ける平行四辺形の内接円の径を大きくすることで捻じり強さを大きくし、ハンドピースによる大きな回転力を伝えることを可能としたものである。 Furthermore, by increasing the diameter of the inscribed circle of the parallelogram in the cross section near the tip of the working part, the torsional strength is increased and it is possible to transmit a large rotational force by the handpiece. is there.
　作業部は、移行部から先端にかけて細くなるテーパ状に形成されている。作業部のテーパはＩＳＯでは２／１００と規格化されている。しかし、必ずしも前記テーパに限定するものではなく、治療部位に対応させて最適なテーパに適宜設定されることが好ましい。また、作業部の太さは該作業部の先端部位で０．０６ｍｍ～１．４０ｍｍの範囲に設定されており、この範囲内に於ける異なる寸法を有するもの複数種類が規格化されている。また、作業部は螺旋状に形成されており、根管を治療する際には隣接するエッジとの間に隙間が形成されるため、この隙間を介して切削屑を排出することが可能である。 The working part is formed in a tapered shape that narrows from the transition part to the tip. The taper of the working part is standardized as 2/100 in ISO. However, the taper is not necessarily limited to the taper, and it is preferable that the optimum taper is appropriately set according to the treatment site. Further, the thickness of the working portion is set in the range of 0.06 mm to 1.40 mm at the tip portion of the working portion, and a plurality of types having different dimensions within this range are standardized. Further, since the working portion is formed in a spiral shape and a gap is formed between the working portion and the adjacent edge when treating the root canal, it is possible to discharge cutting chips through this gap. ..
　本発明に係る根管治療器具は、治療に際し医師が把持して操作するか、ハンドピースに取り付けて操作するか、を限定するものではない。このため、根管治療器具は操作手法に対応させて、シャフト部が医師が把持し得るように合成樹脂製のハンドルに一体成形され、或いはハンドピースのチャックに把持し得るように金属製のシャンクに一体化されている。 The root canal treatment instrument according to the present invention does not limit whether the treatment is performed by a doctor by grasping it or by attaching it to a handpiece. For this reason, the root canal treatment instrument is integrally molded with a synthetic resin handle so that the shaft portion can be grasped by a doctor, or a metal shank so that the shaft portion can be grasped by the chuck of the handpiece, according to the operation method. Is integrated into.
　本発明に係る根管治療器具は、作業部に於ける最もシャフト部側の横断面は対向した一対の長辺と、対向した一対の短辺と、長い対角線上に形成された鋭いエッジと、短い対角線上に形成された鈍角のエッジとを有する平行四辺形として形成されている。また、作業部の先端近傍の横断面は、前記一対の長辺から連続した一対の辺と、前記一対の短辺から連続した一対の辺と、長い対角線上には前記鋭角のエッジから連続した鋭角のエッジとを有する平行四辺形として形成されている。なお、移行部は、断面が円形のシャフト部と、断面が平行四辺形の作業部とを円滑に繋ぐために形成された部分であって、切削能力はほとんどない。 In the root canal treatment instrument according to the present invention, the cross section of the working portion on the most shaft portion side has a pair of long sides facing each other, a pair of short sides facing each other, and a sharp edge formed on a long diagonal line. It is formed as a parallelogram with obtuse edges formed on a short diagonal. Further, the cross section near the tip of the working portion includes a pair of sides continuous from the pair of long sides, a pair of sides continuous from the pair of short sides, and a long diagonal line continuous from the acute-angled edge. It is formed as a parallelogram with sharp edges. The transition portion is a portion formed to smoothly connect a shaft portion having a circular cross section and a working portion having a parallelogram cross section, and has almost no cutting ability.
　作業部のシャフト部近傍の横断面を構成する平行四辺形に於ける長辺と長い対角線とのなす角よりも、先端近傍の横断面を構成する平行四辺形に於ける長辺と長い対角線とのなす角が大きい。即ち、シャフト部近傍の横断面を構成する平行四辺形よりも、先端近傍の横断面を構成する平行四辺形の方が矩形に近い形状に形成されている。 Rather than the angle between the long side and the long diagonal in the parallelogram that constitutes the cross section near the shaft of the working part, the long side and the long diagonal in the parallelogram that constitutes the cross section near the tip The angle between them is large. That is, the parallelogram forming the cross section near the tip is formed in a shape closer to a rectangle than the parallelogram forming the cross section near the shaft portion.
　上記の如く、作業部の先端近傍の横断面に於ける長辺と長い対角線とのなす角は、シャフト部近傍の横断面に於ける長辺と長い対角線とのなす角よりも大きい。即ち、すくい角は、先端近傍の方が小さくなる。このため、根管を治療する際に、先端近傍では根管壁に対する食い込みを防ぐことが可能となる。この結果、根管の曲がりなどに対して容易に追従することが可能となり、意図した経路での治療を施すことが可能となる。 As described above, the angle formed by the long side and the long diagonal line in the cross section near the tip of the working portion is larger than the angle formed by the long side and the long diagonal line in the cross section near the shaft portion. That is, the rake angle becomes smaller near the tip. Therefore, when treating the root canal, it is possible to prevent the root canal from biting into the root canal wall in the vicinity of the tip. As a result, it becomes possible to easily follow the bending of the root canal and the like, and it becomes possible to perform treatment by an intended route.
　また、作業部の先端近傍の断面積は、該先端近傍の横断面の形状をシャフト部近傍の横断面を構成する平行四辺形の相似形とした場合と比較して、大きくなる。このため、治療中に生じる虞のある破断を防ぐことも可能となり、且つ曲げ剛性が高くなって治療の際に医師に対する良好な反力を伝えること、或いはハンドピースの回転力を確実に伝えることが可能となる。 Further, the cross-sectional area near the tip of the working portion is larger than the case where the shape of the cross section near the tip is similar to the parallelogram constituting the cross section near the shaft portion. For this reason, it is possible to prevent breakage that may occur during treatment, and the flexural rigidity is increased to transmit a good reaction force to the doctor during treatment, or to reliably transmit the rotational force of the handpiece. Is possible.
　本発明に於ける第２の根管治療器具は、作業部の先端から所定位置までの範囲を設定し、この範囲内に於ける横断面の形状を上記した先端近傍の横断面と相似形の横断面からなる平行四辺形としている。また、第３の根管治療器具は、作業部の先端近傍から所定位置までの範囲内に於いて、先端近傍の横断面の平行四辺形からシャフト部近傍の横断面と相似形の平行四辺形となるように、長辺と長い対角線とのなす角を変化させている。 The second root canal treatment instrument in the present invention sets a range from the tip of the working portion to a predetermined position, and the shape of the cross section within this range is similar to the cross section near the tip described above. It is a parallelogram with a cross section. Further, the third root canal treatment instrument is a parallelogram having a cross section near the tip and a parallelogram similar to the cross section near the shaft within a range from the vicinity of the tip of the working portion to a predetermined position. The angle formed by the long side and the long diagonal line is changed so as to be.
　本発明に於いて、作業部の先端近傍とは、該作業部の尖端から０．５ｍｍ～１．０ｍｍの範囲であることが好ましい。しかし、必ずしもこの範囲である必要はなく、０．５ｍｍ～１．５ｍｍ、或いは０．５ｍｍ～２．０ｍｍであっても良い。また、シャフト部近傍とは、作業部の最もシャフト部側の位置から所定の範囲であって、言い換えると、良好な切削性能を発揮する作業部と、該作業部とシャフト部の間に形成され作業部からシャフト部に移行する移行部との境界部分の近傍である。しかし、必ずしもこの境界部分である必要はなく、実際の根管治療を行う際に必要な尖端からの長さを指定しても良い。 In the present invention, the vicinity of the tip of the working portion is preferably in the range of 0.5 mm to 1.0 mm from the tip of the working portion. However, it does not necessarily have to be in this range, and may be 0.5 mm to 1.5 mm or 0.5 mm to 2.0 mm. Further, the vicinity of the shaft portion is a predetermined range from the position on the most shaft portion side of the working portion, in other words, is formed between the working portion exhibiting good cutting performance and the working portion and the shaft portion. It is near the boundary part with the transition part that shifts from the working part to the shaft part. However, it does not necessarily have to be this boundary portion, and the length from the tip required for performing actual root canal treatment may be specified.
　また、作業部の先端近傍からシャフト部側に向けて所定位置までの寸法は特に限定するものではなく、目的の根管治療器具の使用目的や作業部の太さや長さに対応させて適宜設定することが好ましい。本件発明者の知見では、前記作業部の先端からの所定位置としては、作業部全長の略１０％～略７０％の範囲であることが好ましかった。 In addition, the dimension from the vicinity of the tip of the working part to the predetermined position toward the shaft part is not particularly limited, and is appropriately set according to the purpose of use of the target root canal treatment instrument and the thickness and length of the working part. It is preferable to do so. According to the findings of the present inventor, it was preferable that the predetermined position from the tip of the working part was in the range of about 10% to about 70% of the total length of the working part.
　本発明に於いて、根管治療器具の材質を限定するものではなく、オーステナイト系ステンレス鋼、マルテンサイト系ステンレス鋼、形状記憶機能を有するチタン合金などを選択的に利用することが可能である。そして、選択した材質に対し最も適した加工方法によって加工することで、目的の根管治療器具を製造することが好ましい。 In the present invention, the material of the root canal treatment instrument is not limited, and austenitic stainless steel, martensitic stainless steel, titanium alloy having a shape memory function, and the like can be selectively used. Then, it is preferable to manufacture the target root canal treatment instrument by processing the selected material by the most suitable processing method.
　次に、第１実施例に係る根管治療器具の構成について図１～図３により説明する。第１実施例に係る根管治療器具は、作業部の先端から該作業部の長さの略２５％の範囲を所定位置までの範囲として設定し、この範囲内に於ける横断面の形状を先端近傍の横断面と相似形の横断面からなる平行四辺形としている。 Next, the configuration of the root canal treatment instrument according to the first embodiment will be described with reference to FIGS. 1 to 3. In the root canal treatment instrument according to the first embodiment, a range of approximately 25% of the length of the working portion is set as a range from the tip of the working portion to a predetermined position, and the shape of the cross section within this range is set. It is a parallelogram consisting of a cross section similar to the cross section near the tip.
　特に、本実施例に係る根管治療器具は、ハンドピースに取り付けられて回転駆動されるように構成されている。このため、根管治療器具は、シャフト部Ａと、該シャフト部Ａに連続した移行部Ｄと、該移行部Ｄに連続した作業部Ｂと、シャフト部Ａが固定されハンドピースのチャックに把持されるシャンク部Ｃと、を有して構成されている。 In particular, the root canal treatment instrument according to this embodiment is configured to be attached to a handpiece and driven to rotate. Therefore, in the root canal treatment instrument, the shaft portion A, the transition portion D continuous with the shaft portion A, the working portion B continuous with the transition portion D, and the shaft portion A are fixed and gripped by the chuck of the handpiece. It is configured to have a shank portion C to be formed.
　シャフト部Ａから作業部Ｂは１本の材から連続して形成されている。シャフト部Ａは軸状に形成されており、一方側に移行部Ｄ及び作業部Ｂが連続して形成され、他方側がシャンク部Ｃに接続されて一体化している。 The shaft portion A to the working portion B are continuously formed from one material. The shaft portion A is formed in a shaft shape, and the transition portion D and the working portion B are continuously formed on one side, and the other side is connected to the shank portion C and integrated.
　作業部Ｂは、移行部Ｄ側から先端にかけて細くなるテーパ状に形成されており、該作業部Ｂに、シャフト部近傍Ｂａ（断面IIＢａ）、先端近傍Ｂｂ（断面IIＢｂ）、先端近傍から所定長さ範囲のシャフト部側の境界となる所定位置Ｂｃ（断面IIＢｃ）が夫々設定されている。 The working portion B is formed in a tapered shape that narrows from the transition portion D side to the tip, and the working portion B has a shaft portion near Ba (cross section IIBa), a tip near tip Bb (cross section IIBb), and a predetermined length from near the tip. A predetermined position Bc (cross section IIBc), which is a boundary on the shaft portion side of the range, is set respectively.
　シャフト部近傍の断面IIＢａと、先端近傍の断面IIＢｂは異なる形状を有している。即ち、シャフト部近傍の位置に於ける断面IIＢａは、図２（ａ）に示すように、対向した一対の長辺１ａと、対向した一対の短辺２ａからなる平行四辺形で、長い対角線３ａ上に鋭角のエッジ５ａが形成され、短い対角線４ａ上に鈍角のエッジ６ａが形成されている。 The cross section IIBa near the shaft and the cross section IIBb near the tip have different shapes. That is, as shown in FIG. 2A, the cross section IIBa at the position near the shaft portion is a parallelogram consisting of a pair of long sides 1a facing each other and a pair of short sides 2a facing each other, and a long diagonal line 3a. An acute-angled edge 5a is formed on the top, and an obtuse-angled edge 6a is formed on the short diagonal line 4a.
　断面IIＢａに於ける長辺１ａと長い対角線３ａとのなす角αは、本実施例では略２０度であり、負のすくい角に設定されている。しかし、角αを前記角度に限定するものではなく、この角度よりも大きくても良く、小さくても良い。 The angle α formed by the long side 1a and the long diagonal line 3a in the cross section IIBa is approximately 20 degrees in this embodiment, and is set to a negative rake angle. However, the angle α is not limited to the above-mentioned angle, and may be larger or smaller than this angle.
　また、作業部Ｂの先端近傍の位置に於ける断面IIＢｂは、図２（ｂ）に示すように、シャフト部近傍の断面IIＢａを構成する一対の長辺１ａから連続した一対の辺１ｂと、断面IIＢａを構成する対向した一対の短辺２ａから連続した一対の辺２ｂと、長い対角線３ｂ上に鋭角のエッジ５ａから連続したエッジ５ｂ、短い対角線４ｂ上に鈍角のエッジ６ａに連続した鈍角のエッジ６ｂとが形成されている。 Further, as shown in FIG. 2B, the cross section IIBb at the position near the tip of the working portion B includes a pair of long sides 1a continuous from the pair of long sides 1a constituting the cross section IIBa near the shaft portion and a pair of sides 1b. A pair of sides 2b continuous from a pair of opposite short sides 2a constituting the cross section IIBa, an edge 5b continuous from an acute-angled edge 5a on a long diagonal 3b, and an obtuse angle continuous from an obtuse edge 6a on a short diagonal 4b. An edge 6b is formed.
　断面IIＢｂに於ける長辺１ｂと長い対角線３ｂとのなす角βは、シャフト部近傍の断面Ｂａに於ける長辺１ａと長い対角線３ａとのなす角αよりも大きい角度に設定されている。角βは角αよりも大きければよく、数値を限定するものではない。本実施例では、角βは略３５度であり、負のすくい角に設定されている。 The angle β formed by the long side 1b and the long diagonal line 3b in the cross section IIBb is set to be larger than the angle α formed by the long side 1a and the long diagonal line 3a in the cross section Ba near the shaft portion. The angle β may be larger than the angle α and does not limit the numerical value. In this embodiment, the angle β is approximately 35 degrees and is set to a negative rake angle.
　このため、断面IIＢｂに於けるすくい角は、断面IIＢａに於けるすくい角よりも小さくなる。また、断面IIＢｂの内接円（コア）８ｂの直径は、例えばシャフト部近傍の断面IIＢａの相似形を先端近傍の断面としたときの内接円の直径と比較して大きくなる。 Therefore, the rake angle in the cross section IIBb is smaller than the rake angle in the cross section IIBa. Further, the diameter of the inscribed circle (core) 8b of the cross section IIBb is larger than the diameter of the inscribed circle when the similar figure of the cross section IIBa near the shaft portion is taken as the cross section near the tip.
　上記のように作業部Ｂの先端近傍では、根管壁に対するすくい角が小さくなることから、切削性能はシャフト部近傍と比較すると低下する。このため、根管の治療に際し、根管壁に対する食い込みを防ぐことが可能となる。また、コアの太さを大きくすることが可能となり、曲げ剛性を増すと共に、捻り強さを大きくして充分な回転力を伝えることが可能となる、 As described above, since the rake angle with respect to the root canal wall is small near the tip of the working portion B, the cutting performance is lower than that near the shaft portion. Therefore, when treating the root canal, it is possible to prevent biting into the root canal wall. In addition, it is possible to increase the thickness of the core, increase the bending rigidity, and increase the torsional strength to transmit a sufficient rotational force.
　作業部の先端近傍から所定位置Ｂｃの断面IIＢｃまでの範囲は、先端近傍の断面IIＢｂの断面形状と相似形の断面形状を有している。この断面IIＢｂは、図２（ｃ）に示すように、シャフト部近傍の断面IIＢａを構成する一対の長辺１ａから連続した一対の辺１ｃと、断面IIＢａを構成する対向した一対の短辺２ａから連続した一対の辺２ｃと、長い対角線３ｃ上に鋭角のエッジ５ａから連続したエッジ５ｃ、短い対角線４ｃ上に鈍角のエッジ６ａに連続した鈍角のエッジ６ｃとが形成されている。 The range from the vicinity of the tip of the working portion to the cross section IIBc of the predetermined position Bc has a cross-sectional shape similar to the cross-sectional shape of the cross section IIBb near the tip. As shown in FIG. 2C, the cross section IIBb includes a pair of long sides 1c continuous from a pair of long sides 1a constituting the cross section IIBa in the vicinity of the shaft portion, and a pair of opposite short sides 2a constituting the cross section IIBa. A pair of sides 2c continuous from the above, an acute-angled edge 5a to a continuous edge 5c on a long diagonal line 3c, and an obtuse-angled edge 6c continuous to an obtuse-angled edge 6a on a short diagonal line 4c are formed.
　そして、断面IIＢｃに於ける長辺１ｃと長い対角線３ｃとのなす角は、先端近傍の断面IIＢｂと同様に、シャフト部近傍の断面IIＢａに於ける長辺１ａと長い対角線３ａとのなす角αよりも大きい角βに設定されている。このため、すくい角は、断面IIＢａに於けるすくい角よりも小さくなる。また、断面IIＢｃのコアの直径も大きくなる。 The angle formed by the long side 1c and the long diagonal line 3c in the cross section IIBc is the angle α formed by the long side 1a and the long diagonal line 3a in the cross section IIBa near the shaft portion, similarly to the cross section IIBb near the tip. It is set to a larger angle β. Therefore, the rake angle is smaller than the rake angle in the cross section IIBa. In addition, the diameter of the core of the cross section IIBc also increases.
　なお、作業部Ｂの横断面の平行四辺形における長辺と短辺の辺比が固定されている領域を辺比固定領域とし、辺比が変化する領域を辺比可変領域とすると、第１実施例に係る根管治療器具は、所定位置Ｂｃから先端側は辺比固定領域であり、所定位置Ｂｃからシャフト部側は辺比可変領域となっている。 If the region where the side ratios of the long side and the short side of the parallelogram of the cross section of the working portion B are fixed is a fixed side ratio region and the region where the side ratio changes is a variable side ratio region, the first The root canal treatment instrument according to the embodiment has a fixed side ratio region from the predetermined position Bc to the tip side, and a variable side ratio region from the predetermined position Bc to the shaft portion side.
　上記の如く形成された第１実施例に係る根管治療器具では、先端近傍Ｂｂから所定位置Ｂｃまでの範囲の曲げ剛性を高くし、高い回転力を伝えることが可能である。 In the root canal treatment instrument according to the first embodiment formed as described above, it is possible to increase the bending rigidity in the range from the tip vicinity Bb to the predetermined position Bc and transmit a high rotational force.
　上記の如き断面IIＢａから断面IIＢｂ、IIＢｃに至る形状の変化は、研削加工による場合には作業部Ｂを形成する際の研削材の追い込み量を調整することで良い。 The change in shape from the cross section IIBa to the cross sections IIBb and IIBc as described above may be achieved by adjusting the amount of the abrasive material driven in when forming the working portion B in the case of grinding.
　次に第２実施例に係る根管治療器具の構成について図４、５により説明する。尚、図に於いて、前述の第１実施例と同一の部分には同一の符号をつけて説明を省略する。 Next, the configuration of the root canal treatment instrument according to the second embodiment will be described with reference to FIGS. 4 and 5. In the figure, the same parts as those in the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted.
　本実施例に於いて、シャフト部近傍の断面ＶＢａの形状及び先端近傍の断面ＶＢｂは、図５（ａ）、（ｂ）に示すように、夫々前述の第１実施例の対応する断面IIＢａ、IIＢｂと同一である。 In this embodiment, the shape of the cross section VBa in the vicinity of the shaft portion and the cross section VBb in the vicinity of the tip portion are the corresponding cross sections IIBa of the first embodiment described above, respectively, as shown in FIGS. 5A and 5B. Same as IIBb.
　作業部Ｂの所定位置Ｂｃからシャフト部側の断面ＶＢｃの形状は、シャフト部近傍の断面ＶＢａと相似形を有している。即ち、断面ＶＢｃは、図５（ｃ）に示すように、対向した一対の長辺１ｃと、対向した一対の短辺２ｃからなる平行四辺形で、長い対角線３ｃ上に鋭角のエッジ５ｃが形成され、短い対角線４ｃ上に鈍角のエッジ６ｃが形成されている。そして、断面ＶＢｃに於ける長辺１ｃと長い対角線３ｃとのなす角は、シャフト部近傍の断面ＶＢａに於ける長辺１ａと長い対角線３ａとのなす角αに設定されている。 The shape of the cross section VBc on the shaft portion side from the predetermined position Bc of the working portion B has a similar shape to the cross section VBa in the vicinity of the shaft portion. That is, as shown in FIG. 5C, the cross section VBc is a parallelogram composed of a pair of long sides 1c facing each other and a pair of short sides 2c facing each other, and an acute-angled edge 5c is formed on a long diagonal line 3c. An obtuse edge 6c is formed on the short diagonal 4c. The angle formed by the long side 1c and the long diagonal line 3c in the cross section VBc is set to the angle α formed by the long side 1a and the long diagonal line 3a in the cross section VBa near the shaft portion.
　このため、作業部Ｂに於ける先端近傍Ｂｂから所定位置Ｂｃまでの範囲で、断面形状は先端近傍の断面ＶＢｂから所定位置Ｂｃの断面ＶＢｃに変化している。即ち、作業部Ｂの先端近傍からシャフト部側に向けた所定位置Ｂｃに至る範囲で、長辺１ｂと長い対角線３ｂとのなす角βがシャフト部近傍の断面ＶＢａに於ける長辺１ａと長い対角線３ａとのなす角αと等しくなるように減少している。このため、作業部Ｂに於ける所定位置Ｂｃでは、断面ＶＢｃがシャフト部近傍の断面ＶＢａの相似形となる。 Therefore, in the range from the tip near the tip Bb to the predetermined position Bc in the working portion B, the cross-sectional shape changes from the cross section VBb near the tip to the cross section VBc at the predetermined position Bc. That is, the angle β formed by the long side 1b and the long diagonal line 3b is as long as the long side 1a in the cross section VBa near the shaft portion in the range from the vicinity of the tip of the working portion B to the predetermined position Bc toward the shaft portion side. It decreases so as to be equal to the angle α formed by the diagonal line 3a. Therefore, at the predetermined position Bc in the working portion B, the cross section VBc has a similar shape to the cross section VBa in the vicinity of the shaft portion.
　なお、第２実施例に係る根管治療器具は、所定位置Ｂｃからシャフト部側は辺比固定領域であり、所定位置Ｂｃから先端側は辺比可変領域となっている。 The root canal treatment instrument according to the second embodiment has a fixed side ratio region from the predetermined position Bc to the shaft portion side, and a variable side ratio region from the predetermined position Bc to the tip side.
　本実施例では、作業部Ｂの先端近傍では高い曲げ剛性を実現し、この先端近傍から所定位置までの範囲で曲げ剛性を減少させてシャフト部側の曲げ剛性に接近させることが可能である。また、ハンドピースの回転力を伝えることは前述の第１実施例に係る根管治療器具と同様である。 In this embodiment, high bending rigidity is realized near the tip of the working portion B, and the bending rigidity can be reduced in the range from the vicinity of the tip to a predetermined position to approach the bending rigidity on the shaft portion side. Further, transmitting the rotational force of the handpiece is the same as that of the root canal treatment instrument according to the first embodiment described above.
　本発明に係る根管治療器具は、歯科治療に於ける根管治療の際に利用することが可能である。 The root canal treatment instrument according to the present invention can be used for root canal treatment in dental treatment.
　Ａ　　　　　　　　シャフト部
　Ｂ　　　　　　　　作業部
　Ｃ　　　　　　　　シャンク部
　Ｄ　　　　　　　　移行部
　Ｂａ　　　　　　　シャフト部近傍
　Ｂｂ　　　　　　　先端近傍
　Ｂｃ　　　　　　　所定位置
　１ａ　　　　　　　長辺
　１ｂ、１ｃ　　　　長辺１ａから連続した辺
　２ａ　　　　　　　短辺
　２ｂ、２ｃ　　　　短辺２ａから連続した辺
　３ａ～３ｃ　　　　長い対角線
　４ａ～４ｃ　　　　短い対角線
　５ａ～５ｃ　　　　鋭角のエッジ
　６ａ～６ｃ　　　　鈍角のエッジ
　７ａ～７ｃ　　　　長い対角線を直径とする円
　８ｂ　　　　　　　内接円 A Shaft part B Working part C Shank part D Transition part Ba Near the shaft part Bb Near the tip Bc Predetermined position 1a Long side 1b 1c Continuous side from long side 1a 2a Short side 2b 2c Continuous side from short side 2a 3a ~ 3c Long diagonal 4a-4c Short diagonal 5a-5c Sharp edge 6a-6c Oblique edge 7a-7c Circle with long diagonal diameter 8b Inscribed circle

Claims (6)

  1. 　シャフト部と、該シャフト部に連続した移行部と、該移行部に連続した作業部と、を有する歯科用根管治療器具であって、
    　前記作業部は前記移行部から先端にかけて細くなるテーパ状に形成されており、
    　前記作業部の最もシャフト部側の横断面は、対向した一対の長辺と、対向した一対の短辺と、長い対角線上に形成された鋭角のエッジと、短い対角線上に形成された鈍角のエッジと、を有する平行四辺形であり、
    　前記作業部の先端近傍の横断面は、一対の前記長辺から連続した辺と、一対の前記短辺から連続した辺と、長い対角線上に形成された前記鋭角のエッジから連続した鋭角のエッジと、短い対角線上に形成された前記鈍角のエッジから連続した鈍角のエッジと、を有する平行四辺形であり、先端近傍の前記長辺から連続した辺と長い対角線とのなす角がシャフト部側の前記長辺と長い対角線とのなす角よりも大きいことを特徴とする歯科用根管治療器具。     A dental root canal treatment instrument having a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion.
    The working portion is formed in a tapered shape that narrows from the transition portion to the tip.
    The cross section of the working portion on the most shaft portion side is a pair of long sides facing each other, a pair of short sides facing each other, an acute-angled edge formed on a long diagonal line, and an obtuse angle formed on a short diagonal line. It is a parallelogram with edges,
    The cross section near the tip of the working portion includes a pair of sides continuous from the long side, a pair of sides continuous from the short side, and an acute-angled edge continuous from the acute-angled edge formed on a long diagonal line. It is a parallel quadrilateral having an acute-angled edge formed on a short diagonal line and an acute-angled edge continuous from the acute-angled edge, and the angle formed by the long diagonal line and the continuous side from the long side near the tip is on the shaft portion side. A dental root canal treatment instrument characterized in that it is larger than the angle formed by the long side and the long diagonal line.
  2. 　シャフト部と、該シャフト部に連続した移行部と、該移行部に連続した作業部と、を有する歯科用根管治療器具であって、
    　前記作業部は前記移行部から先端にかけて細くなるテーパ状に形成されており、
    　前記作業部の最もシャフト部側の横断面は、対向した一対の長辺と、対向した一対の短辺と、長い対角線上に形成された鋭角のエッジと、短い対角線上に形成された鈍角のエッジと、を有する平行四辺形であり、
    　前記作業部の先端近傍の横断面は、一対の前記長辺から連続した辺と、一対の前記短辺から連続した辺と、長い対角線上に形成された前記鋭角のエッジから連続した鋭角のエッジと、短い対角線上に形成された前記鈍角のエッジから連続した鈍角のエッジと、を有する平行四辺形であり、先端近傍の前記長辺から連続した辺と長い対角線とのなす角がシャフト部側の前記長辺と長い対角線とのなす角よりも大きく、且つ前記作業部の所定位置から先端側の横断面の平行四辺形の長辺と長い対角線とのなす角は、先端近傍の前記長辺から連続した辺と長い対角線とのなす角と同じ角度で固定されていることを特徴とする歯科用根管治療器具。     A dental root canal treatment instrument having a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion.
    The working portion is formed in a tapered shape that narrows from the transition portion to the tip.
    The cross section of the working portion on the most shaft portion side is a pair of long sides facing each other, a pair of short sides facing each other, an acute-angled edge formed on a long diagonal line, and an obtuse angle formed on a short diagonal line. It is a parallelogram with edges,
    The cross section near the tip of the working portion includes a pair of sides continuous from the long side, a pair of sides continuous from the short side, and a sharp edge continuous from the sharp edge formed on a long diagonal line. It is a parallel quadrilateral having a blunt edge formed on a short diagonal line and a continuous blunt edge, and the angle formed by the long diagonal side and the long diagonal line near the tip is on the shaft portion side. The angle between the long side of the parallel quadrilateral and the long diagonal of the cross section on the tip side from the predetermined position of the working part, which is larger than the angle formed by the long side and the long diagonal line, is the long side near the tip. A dental root canal treatment instrument characterized in that it is fixed at the same angle as the angle formed by the continuous side and the long diagonal line.
  3. 　シャフト部と、該シャフト部に連続した移行部と、該移行部に連続した作業部と、を有する歯科用根管治療器具であって、
    　前記作業部は前記移行部から先端にかけて細くなるテーパ状に形成されており、
    　前記作業部の最もシャフト部側の横断面は、対向した一対の長辺と、対向した一対の短辺と、長い対角線上に形成された鋭角のエッジと、短い対角線上に形成された鈍角のエッジと、を有する平行四辺形であり、
    　前記作業部の先端近傍の横断面は、一対の前記長辺から連続した辺と、一対の前記短辺から連続した辺と、長い対角線上に形成された前記鋭角のエッジから連続した鋭角のエッジと、短い対角線上に形成された前記鈍角のエッジから連続した鈍角のエッジと、を有する平行四辺形であり、先端近傍の前記長辺から連続した辺と長い対角線とのなす角がシャフト部側の前記長辺と長い対角線とのなす角よりも大きく、且つ前記作業部の所定位置からシャフト部側の横断面の平行四辺形の長辺と長い対角線とのなす角は、最もシャフト部側の前記長辺と長い対角線とのなす角と同じ角度で固定されていることを特徴とする歯科用根管治療器具。     A dental root canal treatment instrument having a shaft portion, a transition portion continuous with the shaft portion, and a working portion continuous with the transition portion.
    The working portion is formed in a tapered shape that narrows from the transition portion to the tip.
    The cross section of the working portion on the most shaft portion side is a pair of long sides facing each other, a pair of short sides facing each other, an acute-angled edge formed on a long diagonal line, and an obtuse angle formed on a short diagonal line. It is a parallelogram with edges,
    The cross section near the tip of the working portion includes a pair of sides continuous from the long side, a pair of sides continuous from the short side, and a sharp edge continuous from the sharp edge formed on a long diagonal line. It is a parallel quadrilateral having an blunt edge formed on a short diagonal line and a continuous blunt edge, and the angle formed by the long diagonal side and the long diagonal line near the tip is on the shaft portion side. The angle between the long side of the parallel quadrilateral and the long diagonal of the cross section on the shaft side from the predetermined position of the working part is larger than the angle formed by the long side and the long diagonal line. A dental root canal treatment instrument characterized in that it is fixed at the same angle as the angle formed by the long side and the long diagonal line.
  4. 　シャフト部と、該シャフト部に連続した移行部と、該移行部に連続した横断面形状が平行四辺形の作業部と、を有する歯科用根管治療器具であって、
    　前記作業部は、横断面の長辺と短辺の辺比が固定されている辺比固定領域と、長辺と短辺の辺比が変化する辺比可変領域と、を有することを特徴とする歯科用根管治療器具。     A dental root canal treatment instrument having a shaft portion, a transition portion continuous with the shaft portion, and a working portion having a parallelogram having a cross-sectional shape continuous with the transition portion.
    The working portion is characterized by having a fixed side ratio region in which the side ratios of the long side and the short side of the cross section are fixed, and a variable side ratio region in which the side ratio of the long side and the short side changes. Dental root canal treatment instrument.
  5. 　前記辺比固定領域が前記作業部の先端側に設けられ、前記辺比可変領域が前記作業部のシャフト部側に設けられていることを特徴とする請求項４に記載の歯科用根管治療器具。 The dental root canal treatment according to claim 4, wherein the side ratio fixed region is provided on the tip end side of the working portion, and the side ratio variable region is provided on the shaft portion side of the working portion. Instrument.
  6. 　前記辺比固定領域が前記作業部のシャフト部側に設けられ、前記辺比可変領域が前記作業部の先端側に設けられていることを特徴とする請求項４に記載の歯科用根管治療器具。 The dental root canal treatment according to claim 4, wherein the side ratio fixed region is provided on the shaft portion side of the working portion, and the side ratio variable region is provided on the tip end side of the working portion. Instrument.
PCT/JP2020/031724 2019-08-22 2020-08-21 Dental root canal treatment instrument WO2021033777A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2019-151995 2019-08-22
JP2019151995A JP2021029540A (en) 2019-08-22 2019-08-22 Dental root canal treatment tool

Publications (1)

Publication Number Publication Date
WO2021033777A1 true WO2021033777A1 (en) 2021-02-25

Family

ID=74661132

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2020/031724 WO2021033777A1 (en) 2019-08-22 2020-08-21 Dental root canal treatment instrument

Country Status (2)

Country Link
JP (1) JP2021029540A (en)
WO (1) WO2021033777A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150216624A1 (en) * 2013-06-20 2015-08-06 Dentsply International Inc. Endodontic instruments
JP2016504142A (en) * 2013-01-30 2016-02-12 メルフェール インストルメンツ ホールディング エスアエールエル Root canal drilling device
CN206044757U (en) * 2016-07-26 2017-03-29 深圳市速航科技发展有限公司 A kind of non-elastic root canal file for waiting shaft section

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016504142A (en) * 2013-01-30 2016-02-12 メルフェール インストルメンツ ホールディング エスアエールエル Root canal drilling device
US20150216624A1 (en) * 2013-06-20 2015-08-06 Dentsply International Inc. Endodontic instruments
CN206044757U (en) * 2016-07-26 2017-03-29 深圳市速航科技发展有限公司 A kind of non-elastic root canal file for waiting shaft section

Also Published As

Publication number Publication date
JP2021029540A (en) 2021-03-01

Similar Documents

Publication Publication Date Title
US8182265B2 (en) Endodontic instrument with multi-tapered flutes
US9333050B2 (en) Gutta-percha remover
US6514076B1 (en) Precipitation hardenable stainless steel endodontic instruments and methods for manufacturing and using the instruments
EP2174616B1 (en) Stainless steel bur
EP1184004B1 (en) Endodontic instrument
JP4042814B2 (en) Dental root canal treatment instrument
US5842862A (en) Endodontic tool
JP4214285B2 (en) Dental root canal treatment instrument and manufacturing method thereof
JP2002253578A (en) Dental reamer
EP2151212B1 (en) Rotary drive cutter for dentistry
US20050026109A1 (en) Multi-tapered dental files
WO2021033776A1 (en) Dental root canal treatment instrument
WO2021033777A1 (en) Dental root canal treatment instrument
WO2002062251A2 (en) Multi-tapered dental files
JP2021119964A (en) Dental root canal treatment instrument
CN113197685B (en) Dental root canal treatment instrument
JP4214286B2 (en) Dental root canal treatment instrument and manufacturing method thereof
US20230200936A1 (en) Endodontic instrument, in particular for reaming a root canal
WO2021070680A1 (en) Dental file
JP4214283B2 (en) Root canal treatment instrument
WO1997039696A1 (en) Endodontic instrument having a chisel tip
CN114052948A (en) Dental file
AU2002242110A1 (en) Multi-tapered dental files

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20853676

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20853676

Country of ref document: EP

Kind code of ref document: A1