Interdental cleaning tool

Abstract

To provide an interdental cleaning tool capable of adjusting the tension of dental floss and having excellent operability and cleaning performance.SOLUTION: The dental floss holder includes a handle 20 having a wide body part 60 to be gripped by a user, a shoulder part 50 tapered toward the tip side, a narrow neck part 40 extending to the tip side, and a pair of arm parts 30, and the dental floss 10 laid over the pair of arm parts. The portion extending from the neck portion to the body portion includes a pair of operation pieces 70 that are respectively continuous with proximal end portions of the pair of arm portions at a distal end portion of the neck portion, extend while being separated from each other in the longitudinal direction, and are continuous on a proximal end side of the body portion, and pressing force receiving portions 62 that face each other in a tapered shape parallel to each other or approaching each other toward a distal end along the longitudinal direction are respectively provided at positions of the pair of operation pieces close to a distal end side of the body portion, and a pressing force received by the pressing force receiving portion is transmitted to the pair of arm portions via the shoulder portion and the neck portion. The tension of the dental floss is changed according to the pressing force.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an interdental cleaning tool, and more particularly to an interdental cleaning tool that allows adjustment of the tension of dental floss. [Background technology]

[0002] In order to more effectively prevent dental caries and periodontal disease, in addition to cleaning with a toothbrush, people are now using interdental cleaners to clean between teeth that are difficult to clean adequately with a toothbrush. These interdental cleaners have a pair of arms supporting both ends of dental floss and equipped with handles connected to the arms. By gripping the handles with the fingers, the dental floss can be inserted between the teeth to clean between them, making them highly convenient.

[0003] However, if the dental floss supported by the pair of arms is loose and the tension is low, the interdental cleaning ability is good but the insertion ability between the teeth may be impaired, and conversely, if the looseness is low and the tension is high, the interdental insertion ability is good but the interdental cleaning ability is relatively poor. Therefore, to achieve both the ease of insertion and cleaning ability of the dental floss between the teeth, an interdental cleaning tool that allows the tension of the dental floss to be adjusted has been proposed (Patent Document 1).

[0004] Patent Document 1 describes a dental floss holder in which a pair of symmetrically shaped members (arms) having a first end, an intermediate portion, and a second end provided in that order from the distal end, are integrally formed with each other at the end of the second end opposite the first end, and an interdental cleaner (second preferred embodiment, etc.) in which dental floss is provided between the distal ends of the first ends of the arms. In this dental floss holder, the pair of arms are connected to each other by a hinge portion at the intermediate portion, and a finger grip surface where a user grips the arm is provided at a portion adjacent to the intermediate portion that tapers toward the dental floss at the second end of the arm. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 11-197162 Summary of the Invention [Problem to be solved by the invention]

[0006] As described above, the dental floss holder having the structure described in Patent Document 1 has a gripping portion close to the dental floss. Therefore, when inserting or removing the dental floss between the molars while applying tension to the dental floss, the user's fingers come into contact with the mouth. Furthermore, the user must apply stress with the fingers near the dental floss, which requires the user to press the finger grip portion firmly. This creates concerns about poor operability and cleaning performance when cleaning between the molars. To avoid this problem, the user must grip the tapered portion of the second end of the arm with the fingers. Furthermore, when gripping the dental floss holder in this position with the fingers, only two fingers are needed, which applies stress that pushes the gripping portion toward the tip, making it difficult to hold the dental floss holder. This also creates concerns about poor operability and cleaning performance.

[0007] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an interdental cleaning tool that allows adjustment of the tension of dental floss and is easy to operate and has excellent cleaning properties. [Means for solving the problem]

[0008] The interdental cleaning tool according to the present invention comprises a handle having a wide body portion that extends longitudinally in a predetermined direction and is gripped by a user, a shoulder portion that tapers from the tip of the body toward the tip side, a narrow neck portion that extends from the tip of the shoulder toward the tip side, and a pair of arms that extend longitudinally from the tip of the neck at a distance from each other; and dental floss stretched over the pair of arms. a portion extending from the neck portion to the body portion includes a pair of operation pieces that are continuous with base ends of the pair of arms at the distal end of the neck portion, extend apart in the longitudinal direction, and are continuous with the base end side of the body, The pair of operation pieces each have a pair of pressing force receiving portions provided at positions near the tip of the body portion, the pressing force receiving portions being parallel to each other along the longitudinal direction or tapering toward the tip, The pressing force received by the pressing force receiving portion is transmitted to the pair of arms via the shoulder portion and the neck portion, and the tension of the dental floss is changed according to the pressing force.

[0009] The tip ends of the pair of arms are each provided with a floss holding portion that fixes both ends of the dental floss, and when the pressing force is not applied, the deflection rate, which is the ratio (B / A) of the distance A between the floss holding portions to the length B of the dental floss placed between the floss holding portions, may be 1.05 to 1.7.

[0010] The pair of operation pieces may be curved and continuous on the base end side.

[0011] The handle may be made of synthetic resin, and the synthetic resin may have a flexural modulus of elasticity of 800 to 2200 MPa as measured in accordance with JIS K7171.

[0012] The pair of operation pieces may have a uniform thickness.

[0013] At the base ends of the pair of arms, the pair of arms may be integrally formed via a thin hinge portion, and the minimum thickness of the hinge portion in the longitudinal direction may be 0.4 to 0.8 mm. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide an interdental cleaning tool that allows adjustment of the tension of dental floss and has excellent operability and cleaning properties. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a perspective view schematically illustrating an interdental cleaning tool according to a representative embodiment of the present invention. [Figure 2A] FIG. 2 is a plan view of the interdental cleaning tool shown in FIG. [Figure 2B] FIG. 2 is a side view of the interdental cleaning tool shown in FIG. [Figure 3] FIG. 2 is a diagram schematically illustrating the operation of the interdental cleaning tool shown in FIG. 1, and is a plan view schematically illustrating a state in which a pressing force is applied. [Figure 4] FIG. 10 is a plan view schematically showing another interdental cleaning tool according to an embodiment of the present invention. [Figure 5] FIG. 2 is a diagram showing the results of a simulation of the relationship between the pressing force and the distance between the tips of the arms when the thickness (minimum thickness) of the hinge part is changed in the handle of the interdental cleaning tool shown in FIG. [Figure 6] FIG. 2 is a diagram showing the results of simulation calculations of the relationship between the pressing force and the distance between the tips of the arm portions when the type of material of the handle of the interdental cleaning tool shown in FIG. 1 is changed. DETAILED DESCRIPTION OF THE INVENTION

[0016] An interdental cleaning tool according to an embodiment of the present invention will be described below with reference to the accompanying drawings. In this embodiment, each direction will be defined based on the up-down, front-rear, and left-right directions shown in Figure 1. The up-down, front-rear, and left-right directions are mutually orthogonal. Furthermore, the top of the up-down direction is the tip side, and the bottom is the base side, and the up-down direction corresponds to the longitudinal direction.

[0017] As shown in Figures 1 to 2B, an interdental cleaning tool 1 according to an embodiment of the present invention includes dental floss 10 and a handle 20. The handle 20 has, in order from the tip, a pair of arms 30, a neck portion 40, a shoulder portion 50, and a body portion 60. The dental floss 10 is stretched across the pair of arms 30.

[0018] The body 60 is configured to be long in the vertical direction and wide in the horizontal direction, and functions as the part that is gripped by the user. The shoulder 50 is configured to taper from the tip of the body 60 toward the tip side in the horizontal direction. The neck 40 is configured to extend further toward the tip side from the tip of the shoulder 50 and narrow in the horizontal direction. The pair of arms 30 extend vertically from the tip of the neck 40 with a gap between them.

[0019] In this embodiment, the pair of arms 30 are each composed of a pair of arm base ends 31 that extend upward from the distal end of the neck 40, bifurcating in approximately left-right directions and curving, and then extending upward parallel to each other. The pair of arm tip ends 32 are continuous with the distal ends of the arm base ends 31, extending obliquely backward and parallel to each other. Furthermore, the pair of arms 30 are connected and integrated at the distal ends of the pair of arm base ends 31 (ends opposite the side adjacent to the arm tip ends 32) by a hinge 33 that can be deformed to adjust the distal-end spacing between the pair of arms 30. As shown in FIG. 2A , in this embodiment, the pair of arms 30 as a whole have a substantially U-shaped structure in a plan view. Furthermore, opposing floss holders 34 for fixing both ends of the dental floss 10 are provided at the distal ends of the pair of arm tip ends 31, respectively.

[0020] The portion extending from the neck 40 to the body 60 is composed of a pair of operating pieces 70. The pair of operating pieces 70 are connected to the base ends of the pair of arm sections 30 at the tip end of the neck 40, extend apart in the vertical direction, and are connected to the base end side of the body 60. In this embodiment, the pair of operating pieces 70 are integrated by a U-shaped connecting section 61 that curves in an arc at the base end side.

[0021] In this embodiment, the pair of operation pieces 70 each have a pair of pressure force receiving portions 62 disposed parallel to and facing each other in the up-down direction, near the distal end of the body portion 60. In the example shown in FIGS. 1, 2A, and 2B, the body portions 60 of the pair of operation pieces 70 have a plate-like structure that faces parallel from the distal end to the proximal end and are integrated by a U-shaped, plate-like connecting portion 61. The pressure force receiving portion 62 is configured to be wider in the front-to-rear direction than other portions of the body portion 60 to facilitate finger pressure, and has a recess 63 facing the opposing pressure force receiving portion 62. The neck portion 40 and shoulder portion 50 of the pair of operation pieces 70 also have a plate-like structure and are disposed facing each other, with the body portion 60 and shoulder portion 50, and the shoulder portion 50 and neck portion 40 smoothly connected. The boundary between the shoulder portion 50 and neck portion 40 is where the distance between the pair of operation pieces 70 faces each other is smallest. At this boundary portion or its vicinity, a restricting portion 71 is formed that brings the pair of operating pieces 70 into contact with each other to prevent excessive deformation when the pressure force receiving portion 62 is pressed with a finger. Therefore, the neck portions 40 of the pair of operating pieces 70 are arranged so that they become wider from the boundary portion with the shoulder portion 50 toward the tip end, and the distance between them increases. The size of the left-right distance at the portion where the distance between the pair of operating pieces 70 is smallest (also referred to as the minimum gap portion) can be determined appropriately depending on the physical properties of the constituent materials, etc.

[0022] The respective tip ends of the neck portions 40 of the pair of operating pieces 70 are continuously integrated at the respective end portions of the arm base ends 31 of the pair of arm portions 30 so as to intersect on both the left and right sides of the hinge portion 33, respectively.

[0023] The interdental cleaning tool 1 according to this embodiment has the above-described structure, and transmits the pressure received by the pressure receiving portion 62 to the pair of arms 30 via the shoulder portion 50 and the neck portion 40, thereby changing the tension of the dental floss 10 in response to the pressure. Specifically, as shown in Fig. 3, by applying pressure to the pressure receiving portion 62 with a finger in the opposing left-right directions indicated by the arrows, the distance between the two pressure receiving portions 62 is narrowed in response to the pressure, and the distance between the shoulder portions 50 and the neck portions 40 of the pair of operation pieces 70 is also narrowed. As a result, the hinge portion 33 located between the tips of the neck portions 40 of the pair of operation pieces 70 bends in response to the pressure, with the hinge portion 33 serving as a fulcrum, and moves in a direction that increases the tension of the dental floss 10, i.e., in a direction that causes the tips of the pair of arms 30 to open apart.

[0024] As described above, the neck portion 40 and shoulder portion 50 of a predetermined structure are provided between the body portion 60 held by the user and the arm portion 30, the distal end of which is provided with the dental floss 10, thereby ensuring a suitable distance between the dental floss 10 and the fingers gripping the body portion 60. Therefore, even when used on back teeth, for example, operability is not impaired compared to conventional devices, and the distance between the point of application of pressure and the hinge portion 33, which serves as the fulcrum, is ensured, allowing the tension of the dental floss 10 to be adjusted with less pressure than conventional devices. Furthermore, the body portion 60 is wide and extends vertically, making it easy to grip with three or more fingers on one hand. The pair of pressure-receiving portions 62 are provided parallel and opposite to each other near the distal end of the body portion 60, ensuring that the pressure applied by the fingers is reliably transmitted to the pair of arms 30 without slipping on the handle 20, making it easy to operate while applying pressure. As a result, the device is also easy to clean.

[0025] In this embodiment, when assisting in the insertion of dental floss 10 between teeth with fingers (e.g., index fingers) of the same hand other than the two fingers (e.g., thumb and middle finger) gripping the pressure force receiving portions 62, recesses (notches) 72 are provided on the front surfaces of the portions extending from the shoulder portions 50 to the neck portion 40 of the pair of operation pieces 70 (positions closer to the tips of the shoulder portions 50 in this embodiment) for the purpose of suppressing vertical movement of the auxiliary fingers and efficiently transmitting the pressure force to the rear side when the auxiliary fingers are positioned distal to the pressure force receiving portions 62 of the operation pieces 70. From the viewpoint of this purpose, it is preferable that the recesses 72 have a recessed structure that is recessed in the direction in which dental floss 10 is inserted between teeth. The recesses 72 may be provided as needed.

[0026] In the example shown in FIGS. 1-2B, the pair of pressure-receiving portions 62a are positioned toward the distal ends of the body portions 60 of the pair of operating pieces 70, facing each other in parallel along the vertical direction. However, as in the interdental cleaning tool 1a according to a modified example shown in FIG. 4, the pair of pressure-receiving portions 62a may be positioned so that they taper toward the distal ends of the body portions 60a of the pair of operating pieces 70a. In the modified example shown in FIG. 4, the body portions 60a of the operating pieces 70a have a plate-like structure that tapers toward each other in a similar manner from the distal end to the proximal end, and are integrated by a plate-like connecting portion 61a that curves in an arc. Arranging the pair of pressure-receiving portions 62a facing each other in such a tapered manner prevents fingers from slipping toward the proximal end when applying pressure, improving operability. Other components of the interdental cleaning tool 1a according to the modified example are the same as those of the interdental cleaning tool 1 shown in FIGS. 1-2A, and the same components are designated by the same reference numerals.

[0027] The length (B) of the dental floss 10, both ends of which are fixed by the floss holders 34 at the distal ends of the arms 30, may be long enough to insert smoothly and comfortably between all teeth and clean them. This length may be 1 mm longer than the distance (A) between the floss holders 34 when no pressure is applied, as long as it allows smooth insertion into the maxillary first molar, which has the largest crown thickness. On the other hand, when a toothbrush leaves unbrushed areas, the area may be wider than just the mesiodistal area between teeth. Therefore, a length that covers approximately one-third (33.3%) of the crown of the first molar is preferable to ensure smooth removal of such unbrushed areas. Furthermore, when inserting or removing dental floss 10 between teeth, it is preferable for the degree of deflection to be smaller than initially. Therefore, from the viewpoint of ease of inserting and extracting the floss and ease of cleaning, it is preferable to set the distance A between the floss-holding parts 34 and the length B of the dental floss 10 so that the deflection ratio (B / A), which is the ratio of the distance A between the floss-holding parts 34 to the length B of the dental floss 10 placed between the floss-holding parts 34, is 1.05 to 1.7 when no pressing force is applied. The distance (A) between the floss-holding parts 34 can be selected appropriately depending on the age, etc., and can be set to, for example, 14 to 17 mm.

[0028] The handle 20 is preferably made of a synthetic resin. Such a synthetic resin is preferably one that allows a typical user to grip the handle with their fingers and smoothly transmit the pressure applied by the pressure force receiving portion 62 to the arm portion 30, and that can change the tension of the dental floss 10 to a desired tension (degree of deflection). The material of the handle 20 can be selected appropriately depending on its shape and structure, but is preferably one that has a flexural modulus of elasticity of 800 to 2200 MPa as measured in accordance with JIS K7171.

[0029] Examples of synthetic resins include nylon, rayon, polyester, polyolefin, polyoxymethylene (POM), acetate polymer, fluororesin, polyether ether ketone (PEEK), and acrylonitrile-butadiene-styrene copolymer (ABS resin). Examples of polyesters include polyethylene terephthalate (PET). Examples of polyolefins include polyethylene (PE) and polypropylene (PP). Examples of fluororesins include polytetrafluoroethylene (PTFE). Of these, PP is particularly preferred.

[0030] As materials for the dental floss 10, in the case of multifilaments, nylon, polyester, polyethylene (PE), and thermoplastic elastomers are preferred, with a fineness of 495 to 1530 denier (550 to 1700 dtex), and the thickness of each single filament constituting the multifilament is preferably 0.9 to 10.8 denier (1 to 12 dtex).In the case of monofilaments, polytetrafluoroethylene (PTFE) is preferred, with a fineness of 540 to 1440 denier (600 to 1600 dtex).

[0031] 2A and 2B can be selected depending on the type, physical properties, shape, structure, etc. of the constituent material of the handle 20, but is preferably generally 0.4 to 0.8 mm from the viewpoint of generating a desired tension according to a pressure that can be comfortably applied by a general user when gripping with the fingers. In addition, the size of the hinge 33 in the left-right direction (the width of the hinge) can also be selected depending on the type, physical properties, shape, structure, etc. of the constituent material.

[0032] 2A and 2B, the thickness t2 of the pair of operation pieces 70 is preferably uniform throughout, including the connecting portion 61. There are no particular limitations on the width of the operation piece 70 in the front-rear direction, but it is preferable that the base end side of the pressing force receiving portion 62 is larger than the tip end side. In addition, it is preferable that the thickness of the pair of arm portions 30 is uniform except for the portion of the hinge portion 33.

[0033] The following describes the results of simulations of the relationship between the pressure and the distance between the tips of the arm portions 30 when a predetermined amount of pressure is applied to the pressure-force receiving portion 62, with the thickness t1 of the hinge portion 30 and the material of the handle 20 being changed for the handle 20 shown in Fig. 1. The distance (A) between the tips of the pair of arm portions 30 when no pressure is applied is 15 mm, the width of the thin hinge portion 30 is 2 mm, the size of the minimum gap is 2 mm, and the thickness t2 of the operating piece 70 is 2.5 mm. The pressure is applied at 10 levels from 1 N to 10 N on one side, and when the distance between the tips reaches a maximum value with a load of 10 N or less, the calculation results up to that maximum value are shown.

[0034] (Thickness t1 of hinge part 30 and distance between tips) The calculations were made assuming that the material of the handle 20 was PP (flexural modulus: 890 MPa). The calculation results are shown in Table 1 and FIG. 5 (a graph of the results of Table 1). The unit of values ​​in Table 1 is mm.

[0035] [Table 1]

[0036] As shown in Table 1 and Figure 5, when the thickness of the hinge portion 30 is changed, it is possible to widen the distance between the tip ends by 1 mm or more from the initial distance of 15 mm with a load of about 2N to 3N on one side. It is also found that when the distance between the tip ends is widened by about 4 mm from the initial distance of 15 mm, a load of about 5N to 10N is required. To clean a wide area between teeth, it is better to apply a small tension to the dental floss, so it is preferable to apply a corresponding pressing force to widen the tip-to-tip distance. Furthermore, for typical users, a pressing force of approximately 6N to 8N on one side maximizes the tip-to-tip distance, ensuring ease of insertion and removal of the floss and allowing adjustment of the dental floss tension to improve cleaning performance in various areas. Thus, when adjusting the tension of the dental floss 10 depending on the area to be cleaned, it can be seen that a preferable thickness of the hinge portion 30 can be 0.4 to 0.8 mm to further improve operability and cleaning performance.

[0037] (Handle 20 material type and tip distance) The calculations were performed assuming that the thickness t1 of the hinge portion 30 was 0.4 mm, and that the material of the handle 20 was a material with a flexural modulus of 3900 MPa (for example, PEEK) and a material with a flexural modulus of 2200 MPa. The calculation results are shown in Table 2 and Figure 6 (a graph of the results of Table 2). The values ​​in Table 2 are in mm. For reference, the results are also shown for the case where the thickness t1 was the same and the material of the handle 20 was a material (PP) with a flexural modulus of 890 MPa.

[0038] [Table 2]

[0039] As shown in Table 2 and Figure 6, when PP with a flexural modulus of 890 MPa is used as the material for handle 20, a load of about 2 N on one side is required to increase the distance between the tips by about 1 mm from the initial distance of 15 mm, and a load of about 5 to 6 N is required to increase the distance between the tips by about 4 mm (the maximum distance in this model system) from the initial distance of 15 mm. Thus, when the flexural modulus of the handle material is 890 MPa, it is clear that a typical user can easily adjust the tension with the fingers of one hand when lowering the tension of the dental floss to clean a wider area between the teeth, or when increasing the tension to insert and pull out the dental floss. When a material with a flexural modulus of 2200 MPa is used for the handle 20, it is found that a load of about 2 to 4 N on one side is required to increase the distance between the tips by about 1 mm from the initial distance of 15 mm. It is also found that a load of about 9 to 10 N on one side is required to increase the distance between the tips by about 3 to 3.5 mm from the initial distance of 15 mm. Thus, when the flexural modulus of the handle material is 2200 MPa, a corresponding pressing force may be required to increase the tension of the dental floss. However, a pressing force of 8 N on one side can increase the distance between the tips by about 2.5 to 3 mm from the initial distance. It is found that by adjusting the tension of the dental floss with the pressing force, it is possible to ensure both ease of cleaning and ease of use. When PEEK, which has a high flexural modulus of elasticity of 3900 MPa, is used as the material for the handle 20, it is found that a load of about 5 N on one side is required to increase the distance between the tips by 1 mm or more from the initial distance of 15 mm. On the other hand, even if a load of 10 N is applied to one side, it is found that the distance between the tips can only be increased by less than 2 mm from the initial distance of 15 mm. Thus, when a material with a high flexural modulus is used, it can be found that it may be difficult to apply the desired tension to the dental floss 10 with a pressing force of 6 to 8 N on one side, as described above, by a typical user. Therefore, when adjusting the tension of the dental floss 10 according to the cleaning area, etc., in order to further improve operability and cleaning ability, it is found that the material of the handle 20 should preferably have a flexural modulus of elasticity of less than 3900 MPa, and more preferably 800 to 2200 MPa. [Explanation of symbols]

[0040] 1, 1a Interdental cleaning tool 10 dental floss 20 Handle 30 Arm section 30 Hinge part 31 Arm base end 32 Arm tip 33 Hinge part 34 Floss holder 40 neck 50 Shoulder 60, 60a body 61, 61a connection part 62, 62a Pressing force receiving portion 63 Recess 70, 70a operation piece 71 Regulatory Department 72 recess A. Distance t1, t2 thickness

Claims

1. a handle having a wide body portion that extends longitudinally in a predetermined direction and is gripped by a user, a shoulder portion that tapers from a tip of the body portion toward the tip side, a narrow neck portion that extends from the tip of the shoulder portion toward the tip side, and a pair of arms that extend from the tip of the neck portion in the longitudinal direction with a gap between them; and dental floss stretched over the pair of arms. a portion extending from the neck portion to the body portion includes a pair of operation pieces that are continuous with base ends of the pair of arms at the distal end of the neck portion, extend apart in the longitudinal direction, and are continuous with the base end side of the body, The pair of operation pieces each have a pair of pressing force receiving portions provided at positions near the tip of the body portion, the pressing force receiving portions being parallel to each other along the longitudinal direction or tapering toward the tip, The interdental cleaning tool transmits the pressing force received by the pressing force receiving portion to the pair of arm portions via the shoulder portion and the neck portion, and changes the tension of the dental floss in accordance with the pressing force.

2. The interdental cleaning tool of claim 1, wherein the tip ends of the pair of arms are each provided with a floss holding portion for fixing both ends of the dental floss, and when the pressing force is not applied, the deflection rate, which is the ratio (B / A) of the distance A between the floss holding portions to the length B of the dental floss placed between the floss holding portions, is 1.05 to 1.

7.

3. 3. The interdental cleaning tool according to claim 1, wherein the pair of operating pieces are curved and continuous at their base ends.

4. 3. The interdental cleaning tool according to claim 1, wherein the handle is made of a synthetic resin, and the flexural modulus of the synthetic resin measured in accordance with JIS K7171 is 800 to 2200 MPa.

5. 3. The interdental cleaning tool according to claim 1, wherein the pair of operating pieces have a recessed portion at a position distal to the pressing force receiving portion, the recessed portion facing in a direction in which the dental floss is inserted between the teeth.

6. 3. The interdental cleaning tool according to claim 1, wherein the pair of operating pieces have a uniform thickness.

7. The interdental cleaning tool according to claim 1 or 2, wherein the pair of arms are integrally formed at their base ends via a thin hinge portion, and the minimum thickness of the hinge portion in the longitudinal direction is 0.4 to 0.8 mm.

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