JP6472725B2 - Orthodontic bracket removal tool - Google Patents

Description

The present invention relates to an orthodontic bracket removing tool and an orthodontic bracket removing tool control method.

  Orthodontic treatment for improving the position of the teeth in the oral cavity by moving the misplaced teeth is widely performed. In a typical orthodontic treatment, orthodontic brackets and archwires known as orthodontic appliances are used. The orthodontic bracket is an appliance with a small groove (bracket slot) that is secured to the patient's teeth and the archwire is placed in the bracket slot of the orthodontic bracket. During treatment, the archwire guides the position of the teeth secured to the orthodontic bracket to the correct position using the archwire tension. The distal end of the archwire is often secured to the patient's molar teeth. When the orthodontic bracket and the teeth are fixed, the tooth enamel surface and the orthodontic bracket are bonded with an adhesive. When the treatment is complete, the archwire is removed from the bracket slot of the orthodontic bracket, and then the orthodontic bracket is removed from the adhesively secured tooth. Here, various techniques for removing the orthodontic bracket from the teeth are disclosed.

  Patent Document 1 includes an orthodontic bracket (an orthodontic bracket) having a first gripping tool, a second gripping tool, and a blade extending between the first gripping tool and the second gripping tool. Is used in Japanese Patent Application Laid-Open No. H10-260688). Moreover, when removing an orthodontic bracket from a tooth | gear, the technique which peels an orthodontic bracket from a tooth | gear by mechanical force is disclosed that a braid | blade clamp | tightens the orthodontic bracket releasably.

  In Patent Document 2, an orthodontic bracket (the term orthodontic bracket is used in Patent Document 2) is provided with an inclined cutting surface for cutting an adhesive bonding each tooth, and a residual adhesive. An instrument having a smooth surface to polish is disclosed.

  Patent Document 3 discloses an electrothermal heating means for heating an orthodontic bracket (the term “dental bracket” is used in Patent Document 3), and a tensile force applied to the orthodontic bracket connected to the heating means. An instrument comprising a tensioning means is disclosed. Further, a technique is disclosed in which the heating means heats the orthodontic bracket, and the tension means removes the orthodontic bracket from the teeth with a tensile force that exceeds the bonding force of the heated and relaxed adhesive.

  Patent Document 4 discloses an orthodontic bracket having a distal midline and a saddle-like groove (the term orthodontic bracket is used in Patent Document 4), a distal midline of the orthodontic bracket, and a saddle. An orthodontic bracket removal device having a detachable working end that fits snugly into the groove is disclosed. Also, a technique for removing the orthodontic bracket from the tooth by rapidly heating the orthodontic bracket at the demounting work end heated by electric heat and softening the adhesive bonding the orthodontic bracket to the tooth is disclosed. Has been.

  Non-Patent Document 1 discloses a technique for removing an orthodontic bracket from a tooth by destroying an adhesive using a laser several times stronger than a laser used in normal dental care.

Special table 2010-512969 gazette Special table 2014-500064 gazette Japanese Patent Laid-Open No. 02-013451 Japanese Laid-Open Patent Publication No. 04-242639

“Method of destroying and removing adhesive using Nd: Yag laser”, Kotaro Hayagawa, AJODO magazine, Vol. 5, p. 638-647, November, 2005

  Orthodontic brackets used for orthodontic braces are made of materials that are difficult to deform themselves, such as stainless steel, so to overcome that difficulty in removing them from the teeth after treatment is complete. Various known techniques such as those described above have been employed in the art. However, in recent years, the adhesive strength of the adhesive to fix the orthodontic bracket to the teeth has become stronger with the progress of technology, and the removal of the orthodontic bracket has become more difficult, and the orthodontic bracket has to be removed more carefully. There is a need to do.

  According to the technique described in Patent Document 1, the hand instrument removes the orthodontic bracket from the tooth only by mechanical force. There was a problem that a greater force was applied to the teeth during removal due to the adhesive becoming stronger.

  According to the technique described in Patent Document 2, the adhesive is cut using ultrasonic vibration, and the remaining adhesive is polished using ultrasonic vibration. Here, when cutting the adhesive, the cutting surface must be brought into contact with the adhesive from the gap between the teeth and the orthodontic bracket, and cutting efficiency is poor. Therefore, as the adhesive becomes stronger, it takes a longer time to cut the adhesive, and the cutting surface of the tool bit is more likely to damage the enamel of the teeth. . This problem is also a general problem with dental scalers.

  According to the techniques described in Patent Document 3 and Patent Document 4, since the adhesive becomes stronger, the electric heating amount of the orthodontic bracket has to be increased, and the electric heat that leads the heat to the teeth. There was a risk that undesired heating to the teeth and the surroundings of the teeth would increase as the path became larger. In addition, the electrical heating path with good thermal conductivity is large, and the removal tool is also large, so the adhesive strength of the adhesive has become stronger, so the electrical heating path and removal tool are further enlarged. did.

  Further, from the viewpoint of safety, the problems inherent in the background art described above have become more prominent because the adhesive has more firmly bonded the teeth and the orthodontic bracket. . The orthodontic bracket must be safely removed from the surface of the tooth at the end of treatment, but in the methods described in Patent Documents 1 to 4, there are dangerous factors that apply excessive force to the teeth, When heating the adhesive, there was a risk of using dangerous equipment. In particular, the tooth enamel may be damaged, and there is a risk of applying excessive force to the tooth that is shaken by the trauma. In the technique of Non-Patent Document 1, the intensity of the laser beam required to break the adhesive increases as the adhesive strength becomes stronger. A device that generates high-intensity laser light is expensive, and if high-intensity laser light strikes the retina, there is a risk of blindness.

  In addition to making the adhesive stronger, in recent years ceramic orthodontic brackets with good aesthetics have become widespread instead of stainless steel orthodontic brackets. Ceramics have the property of being less thermally conductive than stainless steel and being easily broken by external forces. Therefore, when removing a ceramic orthodontic bracket from a tooth using a heat source, a stronger heat source was required than when removing a stainless steel orthodontic bracket, resulting in a stronger adhesive. In addition to strengthening the heat source, it was necessary to further strengthen the heat source. Further, when the ceramic orthodontic bracket is removed from the teeth using mechanical force, the ceramic orthodontic bracket is easily broken in the oral cavity of the patient, which is dangerous.

  The problem to be solved by the present invention is to solve the above-mentioned problems caused by the stronger adhesive force of the adhesive and / or the use of ceramic orthodontic brackets instead of stainless steel. . That is, when removing the orthodontic bracket, the orthodontic bracket can be easily removed without applying excessive mechanical force and excessive heat to the teeth and the orthodontic bracket, causing no pain to the patient for a long time. Provide removal technology.

  An orthodontic bracket removing tool of the present invention is an orthodontic bracket removing tool for removing an orthodontic bracket bonded to a tooth by an adhesive from the tooth, and ultrasonic waves are applied to a working end of the orthodontic bracket removing tool. The working end is formed by a high-rigidity member that vibrates by the ultrasonic wave, and is shaped to fit into a bracket slot provided in the orthodontic bracket. Friction heat is generated between the forming surface of the bracket slot of the orthodontic bracket and the working end by the vibration of the end, and the friction heat is transmitted from the orthodontic bracket to the adhesive, and the adhesive The frictional heat transmitted to the softens the adhesive so that the orthodontic bracket can be removed from the teeth.

The method of orthodontic bracket removal tool of the present invention is a control method of the orthodontic bracket removal tool for removing the orthodontic bracket is bonded by the teeth with an adhesive from the tooth, said orthodontic bracket removed An ultrasonic wave is guided to the working end portion of the tool, the working end portion fitted in a bracket slot provided in the orthodontic bracket is vibrated by the ultrasonic wave, and the vibration of the working end portion causes the orthodontic bracket of the orthodontic bracket to vibrate. Friction heat is generated between the forming surface of the bracket slot and the working end, the friction heat is transmitted from the orthodontic bracket to the adhesive, and the frictional heat transmitted to the adhesive is the adhesive. And the orthodontic bracket can be removed from the teeth.

  According to the orthodontic bracket removal technique of the present invention, frictional heat is generated between the forming surface of the orthodontic bracket slot and the working end by the vibration of the working end, and the frictional heat is transferred from the orthodontic bracket to the adhesive. The frictional heat transmitted to the adhesive can soften the adhesive and allow the orthodontic bracket to be removed from the tooth. In this way, since a large mechanical force and a powerful heat source are not used, the teeth and peripheral portions of the teeth are not damaged by these. Since the heat for softening the adhesive is locally generated in the orthodontic bracket in contact with the adhesive, it is extremely safe.

It is a perspective view of an orthodontic bracket removal tool. It is a figure which shows the positional relationship of an orthodontic bracket and a tooth | gear. It is an expansion perspective view of an orthodontic bracket. It is a figure which shows an example of the state by which the work edge part was inserted by the bracket slot. It is a figure which shows an example of the cross-sectional shape of a work edge part. It is a photograph of an orthodontic bracket and a working end.

  The orthodontic bracket removing tool of the embodiment is for removing an orthodontic bracket bonded to a tooth by an adhesive from the tooth. An ultrasonic conduction path for guiding ultrasonic waves is provided at the working end of the orthodontic bracket removing tool. Since the working end is formed of a highly rigid member that vibrates with ultrasonic waves, it vibrates at high speed. Since the working end is shaped to fit into a bracket slot provided in the orthodontic bracket, the working end can vibrate within the bracket slot. Then, frictional heat is generated between the work surface and the bracket slot forming surface of the orthodontic bracket by the vibration of the work end. This frictional heat is transmitted from the orthodontic bracket to the adhesive, and the frictional heat softens the adhesive. In this way, the orthodontic bracket can be removed from the teeth. Here, the working end portion includes not only the portion in contact with the orthodontic bracket when removing the orthodontic bracket in the ultrasonic transmission path of the orthodontic bracket removing tool, but also the portion near the orthodontic bracket, The part that contributes to generation of frictional heat and transmission of ultrasonic vibration.

  The method of removing the orthodontic bracket removing tool of the embodiment is configured to guide ultrasonic waves to the working end of the orthodontic bracket removing tool and vibrate the working end inserted into the bracket slot provided in the orthodontic bracket with ultrasonic waves. The frictional heat is generated between the working surface of the orthodontic bracket by the vibration of the working end, and the frictional heat is transmitted from the orthodontic bracket to the adhesive. Softens the adhesive so that the orthodontic bracket can be removed from the teeth.

  The orthodontic bracket removal tool may have a connecting part that can be gripped by hand to control the position of the working end with respect to the bracket slot, and is arranged at one end of the connecting part and detachable from the ultrasonic generator. A handle coupling portion, a working end portion which may be easily fitted into a bracket slot of the orthodontic bracket, and a shaft for coupling one end of the bending portion to the other end of the coupling portion. May be provided, and a working end portion to which the other end of the bending portion is coupled may be provided. The entire orthodontic bracket removing tool may be configured to function as an ultrasonic conduction path. Here, since the ultrasonic generator has a large shape, it is installed at a position apart from the orthodontic bracket removing tool that is required to be small for insertion into the oral cavity, and the orthodontic bracket removing tool Alternatively, the orthodontic bracket removing tool and the ultrasonic wave generator may be coupled with each other by another ultrasonic conduction path.

  The working end is the main part in the embodiment, and because the frictional heat generated between the working end and the orthodontic bracket is transmitted to the adhesive by the shortest path, how to configure the working end, The performance of the orthodontic bracket removal tool of the embodiment is affected. The working end portion is required to be made of a material having high rigidity in order to transmit ultrasonic waves without loss and generate frictional heat in the orthodontic bracket removing tool. For example, the working end may be formed of stainless steel. Further, it may be suitable for the work of separating the fine adhesive so that the tip of the work end is sharp.

  Next, the dimensions of each part of the working end will be described. Since the absolute position of the orthodontic bracket removal tool changes depending on whether the patient's posture is upright, upward, sideways, or downward, the normal thickness, width, and length If terms are used as they are, the meaning of the terms will be confused. In use of the orthodontic bracket removing tool, the orthodontic bracket removing tool is brought into contact with the orthodontic bracket. More specifically, when the orthodontic bracket removing tool is in use, the working end is brought into contact with the inner surface of the bracket slot. Accordingly, the length of each part of the working end is defined as follows with reference to the position of the patient's teeth and used in the following description to prevent confusion in the meaning of the terms.

  First, an adhesive surface between the orthodontic bracket and the teeth is used as a reference surface. When the orthodontic bracket removing tool is in contact with the orthodontic bracket, the reference surface is parallel to the bottom surface of the concave portion of the bracket slot of the orthodontic bracket. When the reference plane is determined as described above, the height of the working end for social custom is that the orthodontic bracket removal tool is in contact with the orthodontic bracket and teeth when the orthodontic bracket removing tool is in contact with the orthodontic bracket. It can be defined as the length of the working end in the orthogonal direction. Further, the width of the working end in the general sense can be defined as the length of the working end in the vertical direction that is the long axis direction of the tooth. Moreover, the length of the work end part in the common sense can be defined as the length of the work end part in the left-right direction, which is a direction orthogonal to the up-down direction.

  In order to generate large frictional heat, it is necessary to increase the contact area between the working end and the bracket slot inner surface, and it is also necessary to press the working end against the bracket slot inner surface with a certain amount of pressure. In order to generate heat efficiently, it is most desirable that the wide surface of the working end is in contact with the bottom surface of the recess of the bracket slot. Therefore, how to select the length of the working end in the direction orthogonal to the bonding surface between the orthodontic bracket and the tooth, the length of the working end in the vertical direction, and the length of the working end in the left-right direction Is important, but this will be described later.

  Here, the length of the bracket slot into which the archwire is inserted is standardized internationally. The distal end of the archwire is often secured to the patient's molar teeth.

  The vibration direction of the working end portion that generates the frictional heat may be any of the vertical direction, the horizontal direction, and the direction orthogonal to the bonding surface. In principle, the vibration of the working end in the vertical direction generates frictional heat by friction between the bottom surface of the bracket slot and the working end. The vibration of the working end in the left-right direction generates frictional heat due to friction between the bottom surface of the bracket slot and the working end. The vibration of the working end in the direction orthogonal to the bonding surface generates frictional heat due to friction between the side surface of the bracket slot and the working end. Friction depending on the width of the friction surface in the vertical direction, the width of the friction surface in the left-right direction, the width of the friction surface in the direction perpendicular to the bonding surface, and the size of the gap between the working end and the bracket slot The amount of heat generated is different. Frictional heat can also be generated by a combination of two or more vibrations in the vertical direction, the horizontal direction, and the direction orthogonal to the bonding surface. Which vibration direction at the work end is used to generate heat increases the heat generation efficiency. The shape of the work end, the positional relationship between the work end and the bracket slot, the vertical length of the work end, It depends on the length of the direction and the length of the direction orthogonal to the bonding surface.

  There are the following restrictions on the length of the working end in each direction. Since the working end cannot be fitted into the bracket slot unless it is shorter than the vertical length of the bracket slot, the restriction on the vertical length of the working end is absolute. The length in the left-right direction of the working end may vary depending on the length in the left-right direction of the orthodontic bracket, and is preferably slightly longer than the length in the left-right direction of the orthodontic bracket. The length of the working end portion in the direction orthogonal to the bonding surface is preferably slightly longer than the length of the bracket slot in the direction orthogonal to the bonding surface. In this way, it is desirable to extend the length of each part of the working end until it comes out of the bracket slot so that the area of the contact surface between the working end and each face of the bracket slot becomes large. The length of the working end in the vertical direction, the length in the left-right direction, and the length in the direction perpendicular to the bonding surface are not limited to the length of the portion that contacts each surface of the bracket slot, but the working end is bracketed. The length of the portion having a function for fitting into the slot and the margin length for stably securing the contact area with the orthodontic bracket slot are also included.

  Theoretically, the shape of the working end portion having the highest heat generation efficiency is a rectangular parallelepiped (the rectangular parallelepiped also includes a rectangular parallelepiped) that exactly matches the shape of the orthodontic bracket slot extending in the left-right direction. In this shape, if the working end is vibrated in the left-right direction, theoretically, the bottom and side surfaces of the orthodontic bracket slot will always generate friction with the working end, so that the maximum frictional heat can be obtained. Become. However, when the inventor described in the application repeats diligent experiments and evaluates other performances as an orthodontic bracket removal tool, it is found that a rectangular parallelepiped that closely matches the shape of the orthodontic bracket slot is not the most desirable shape. It was.

  According to the inventor's experiment, it is extremely difficult to fit the working end of the rectangular parallelepiped into the orthodontic bracket slot. The reason is that, in the case of the working end portion of the rectangular parallelepiped, it is difficult to align the position of the rectangular parallelepiped that is not inaccurate in the first insertion and the position of the orthodontic bracket slot. Moreover, if the corner | angular part of the work edge part of a rectangular parallelepiped hits a tooth | gear, a tooth | gear will be hurt, and if it hits a gum etc., the part which struck will be hurt. Therefore, the inventor has made improvements and arrived at the shape of the working end as in the following examples.

  Hereinafter, specific examples will be described with reference to the drawings.

  FIG. 1 is a perspective view of an orthodontic bracket removing tool of the embodiment.

  An orthodontic bracket removing tool 1 shown in FIG. 1 includes a connecting portion 2, a shaft portion 3, a bending portion 4, a working end portion 5, a handle coupling portion 6, and a liquid ejection hole 7 as main components. The size of the orthodontic bracket removing tool 1 is set so that the length from the handle coupling portion 6 to the working end portion 5 is in the range of 10 mm to 40 mm, for example, 30 mm so that it can be easily inserted into the oral cavity. The height is 8 mm, for example, and the width is 4 mm, for example. The orthodontic bracket removal tool 1 is made of a metal material that can withstand sterilization by an autoclave, for example, stainless steel.

  The connecting portion 2 is a component that can be grasped by a hand for controlling the position of the working end portion 5 with respect to the bracket slot 11 (see FIG. 2) of the orthodontic bracket 10 (see FIG. 2). A handle coupling portion 6 is disposed at one end of the connecting portion 2. The handle coupling part 6 can be attached to and detached from an ultrasonic wave generation part (not shown). Since the ultrasonic generator is a well-known technique as a dental medical instrument, description thereof is omitted. Further, the handle coupling portion 6 is provided with a liquid transport port (not shown), and the liquid transport port is detachable from a liquid supply device (not shown). Since the liquid supply device is a well-known technique as a dental medical instrument, description thereof is omitted.

  The curved portion 4 provides a sufficient offset to horizontally apply the working end 5 to a groove (bracket slot 11) built in the orthodontic bracket 10. As described above, when the work end 5 is inserted into the bracket slot 11 from the left (for right-handed use), and when the work end 5 is inserted into the bracket slot 11 from the right (for left-handed use), the curved portion The way of turning 4 is different. The curved portion 4 is provided with a liquid ejection hole 7, and when cooling is required by the liquid ejected from the liquid ejection hole 7, transient heating is prevented and foreign substances in the oral cavity are washed away.

  The shaft portion 3 connects the bending portion 4 to the connecting portion 2. The connecting portion 2 can be gripped by hand in order to control the position of the working end portion 5 with respect to the bracket slot 11.

  The working end portion 5 is a member having a function of heating the adhesive. The working end portion 5 forms a flat surface having a thickness along the bottom surface and the side surface of the bracket slot 11. The cross section of the working end 5 is a rectangle with rounded corners, and the working end 5 is always well accommodated in the bracket slot 11 while applying ultrasonic vibration to the working end 5. The reason why the corner of the rectangle is rounded is to prevent the corner of the rectangular parallelepiped working end from being damaged when it hits a tooth, gum or the like.

  FIG. 2 is a diagram showing the positional relationship between the orthodontic bracket 10 and the teeth.

  FIG. 2 is a diagram showing the positional relationship between the orthodontic bracket and the tooth, and is drawn so that the positional relationship can be understood, so the dimensions of each part shown in the drawing are not exact. 2A is a view as seen from the tooth surface direction, FIG. 2B is a view as seen from the tooth cross-sectional direction, and FIG. 2C is a view of the bracket slot 11 as seen from the tooth cross-sectional direction. . Hereinafter, the orthodontic bracket 10 and the bracket slot 11 will be described with reference to FIG.

  This will be described with reference to FIG. The bracket slot 11 is a groove disposed on the surface of the orthodontic bracket 10, and an archwire (not shown) is disposed inside the bracket slot 11 during orthodontic correction.

  This will be described with reference to FIG. The adhesive is, for example, a known dental resin or dental cement.

  This will be described with reference to FIG. As shown in FIG. 2C, each side of the bracket slot 11 has two side surfaces and one bottom surface in the cross section, but actually has four side surfaces (see FIG. 2C). (See FIG. 3).

  FIG. 3 is an enlarged perspective view of the orthodontic bracket 10.

  With reference to FIG. 3, description of each surface of the orthodontic bracket 10 and the size of each part will be given. The orthodontic bracket 10 has an outer surface of the orthodontic bracket 10 denoted by reference signs A, B, H, I, J, and K. Moreover, it has the inner surface of the bracket slot 11 which attached | subjected the code | symbol C, the code | symbol D, the code | symbol E, the code | symbol F, and the code | symbol G. Each inner surface denoted by reference characters C, D, E, and F is a side surface of the bracket slot 11, and an inner surface denoted by a symbol G is a lower surface of the bracket slot 11. Each surface provided with reference A, reference B, reference C, reference D, reference E, reference F, reference G, reference H, reference I, reference J and reference K is defined as outer surface A, outer surface B, side C, side D, The side surface E, side surface F, bottom surface G, top surface H, top surface I, top surface J, and top surface K are defined and used in the following description. The outer surface A and the outer surface B are parallel. The side surface C and the side surface D are located on the same plane (first plane), the side surface E and the side surface F are located on the same plane (second plane), the upper surface H, the upper surface I, the upper surface J, and the upper surface K. Are located on the same plane (third plane). The first plane and the second plane are parallel. The outer surface A and the outer surface B are orthogonal to the first plane and the second plane. The outer surface A, the outer surface B, the first plane, and the second plane are orthogonal to the bottom surface G. The third plane is parallel to the bottom surface G.

  The separation distance between the first plane and the second plane is the vertical length L1, the separation distance between the outer surface A and the outer surface B is the left-right direction length L2 (usually referred to as the major axis), and the third plane is the bottom surface. The distance from G is a direction length L3 (usually referred to as depth) perpendicular to the adhesive surface. As for the size of the bracket slot 11, the vertical length L1 (width) is, for example, 0.457 mm, the horizontal length L2 (major diameter) is, for example, 3.0 mm, and the length L3 (depth) perpendicular to the bonding surface is, for example, 0.75 mm. It is. The vertical length L1 is defined by two types of international standards. According to the first standard, the vertical length L1 is 0.018 inch (corresponding to 0.457 mm), and according to the second standard. The vertical length L1 is 0.022 inch (corresponding to 0.559 mm). The inventor uses a standard product conforming to the first standard or the second standard having the same dimensions regardless of whether the orthodontic bracket 10 is made of ceramic or stainless steel. It was confirmed that the orthodontic bracket removing tool 1 has the same effect.

  FIG. 4 is a view showing a state where the working end portion 5 is inserted into the bracket slot 11.

  In FIG. 4, the working end 5 extends from the tip 5 a (right end) to the position of the outer surface B indicated by a broken line. The tip 5a of the working end 5 is sharp. By sharpening the tip 5a in this way, the work end 5 is easily fitted into the bracket slot 11. In addition, the work end with a sharp tip is also suitable for work to remove fine adhesive. The working end 5 is configured as a part of the bending portion 4, and the tip of the bending portion 4 delimited by the outer surface B eventually becomes the boundary of the working end 5. The above is a case where the working end portion 5 is inserted into the bracket slot 11 from the left direction. Although not shown, when the working end portion 5 is inserted into the bracket slot 11 from the right direction, a curve cut by the outer surface A is cut. As a result, the tip of the portion 4 becomes the boundary of the working end portion 5. That is, the working end portion 5 is not different in physical shape or chemical composition from other parts to be integrally connected, but is easily rubbed with the function of fitting into the bracket slot 11 and the inner surface of the bracket slot 11 to generate frictional heat. It is a site | part which has the function to generate | occur | produce. That is, the working end portion 5 is a functional portion having a slight variation in the range in which these functions are exhibited, depending on the angle at the time of insertion, the magnitude of the applied force, and the like.

  FIG. 5 is a diagram showing a cross-sectional shape of the working end portion 5.

  FIG. 5A is a cross-sectional view of the work end portion 5 taken along the left-right direction when viewed from the up-down direction, and FIG. 5B shows a plane including the outer surface A of the work end portion 5 as the cut surface. It is sectional drawing which makes a cut surface the cross section and the plane containing the outer surface B. Both the cross section of the cut surface by the outer surface A and the cross section of the cut surface by the outer surface B are rectangles with rounded corners.

  When the bracket slot 11 is removed, the flat surface facing the bottom surface G of the work end 5 is arranged so that the flat surface is in contact with the bottom surface G, and the side surface C, side surface D, side surface E, and side surface F of the work end portion 5 are arranged. The flat surface that faces is arranged such that the flat surface is in contact with any one of the side surface C and the side surface D or the side surface E and the side surface F.

  The case where the tip end closer to the tip end 5a of the working end portion 5 has a tapered shape in which the height H becomes smaller and the tip end closer to the tip end 5a of the working end portion 5 becomes smaller in width W will be described. In FIG. 5B, the width W1 <width W2 and the height H1 <height H2 indicate that the tip end of the working end portion 5 has a tapered shape.

  By adopting such a shape, it is possible to achieve the function that can be easily inserted as required for the working end portion 5 by first inserting a tip having a small cross-sectional area first. In addition, by adopting such a shape, it is possible to set how far the work end portion 5 is inserted. When the work end portion 5 is inserted from the left direction, the outer surface B functions as a stopper when the width W2 of the work end portion 5 is equal to or greater than the vertical length L1, and further insertion is impossible. The distance between the cut surface by the outer surface A of the work end 5 and the cut surface by the outer surface B of the work end 5 is the left-right direction length L2. Therefore, the length L4 of the portion protruding from the cut surface by the outer surface A of the working end 5 becomes smaller as the taper of the width W becomes larger. As the taper of the width W increases, the length L4 eventually becomes a negative value, and the tip 5a of the working end 5 remains inside the bracket slot 11.

  When the flat surface of the working end portion 5 is disposed so as to be in contact with the side surface C and the side surface D, the surface in contact with the bottom surface G and the surface in contact with the side surface C and the side surface D are portions that generate frictional heat. Alternatively, when the position of the working end portion 5 is slightly shifted, the flat surface of the working end portion 5 comes to be in contact with the side surface E and the side surface F, and the surface in contact with the bottom surface G, the side surface E, and the side surface F The contacting surface is a part that generates frictional heat. The working end portion 5 having such a cross-sectional shape includes a bottom surface G and two side surfaces (side surface C and side surface D or side surface E and side surface F) among the four side surfaces (side surface C, side surface D, side surface E, and side surface F). ) Can be used as the area of the portion that generates frictional heat (frictional heat generation surface area), so that the heat generation efficiency is high. Here, the amount of the taper with the width W and the taper with the height H is related to the frictional heat generation surface area. It is clear from FIG. 5 that the frictional heat generation surface area on the side surface increases as the taper of the height H decreases, and the frictional heat generation surface area on the bottom surface increases as the taper of the width W decreases. However, it is clear from FIG. 5 that if (height H1)> (direction length L3 orthogonal to the bonding surface), the frictional heat generating surface area on the side surface is maximized regardless of the height H.

  In conclusion, the greater the taper of height H and the taper of width W, the easier the insertion. In particular, it is clear from FIG. 5 that the taper with the width W is related to the ease of insertion. However, the greater the taper of height H and the taper of width W, the smaller the frictional heat generating surface area. On the other hand, the smaller the taper with the height H and the taper with the width W, the more difficult it is to insert, but the area of the frictional heat generating surface increases. Since the height H taper does not significantly affect the ease of insertion, it is effective to reduce the height H taper to increase the frictional heat generating surface area.

  For example, the most preferable shape of the work end 5 is a rectangle having a rounded corner at the cross section of the work end 5 (see FIG. 5), and the vertical length of the work end 5 is the work end 5. (See the taper shape in FIGS. 4 and 5) so that it is equal to the vertical length of the bracket slot 11 at a position away from the tip 5a of the working end 5 by a predetermined length. (See FIGS. 4 and 5). Here, the position away from the tip of the working end 5 by a predetermined length is the position of the B surface. The predetermined length is (L2 + L4) in FIG. The predetermined length is a dimension having a function of determining a position of a stopper that prevents the working end portion 5 from being inserted into the bracket slot 11. The predetermined length can be set to a desired value by determining the taper size of the working end portion 5.

  Fit the numbers. If the width W2 of the working end 5 is 0.457 mm at the position of the B surface, the working end 5 cannot be fitted into the inner surface of the first standard bracket slot 11 (see FIG. 4). In the bracket slot 11 of the second standard, if the width W2 of the work end 5 is 0.559 mm at the position of the B surface, the work end 5 cannot be fitted into the inner surface of the bracket slot 11 any more. The tip 5a of the working end 5 is separated from the position of the B surface by a predetermined length, but the predetermined length can be easily set by previously determining the value of the width W1 or the taper size on the A surface. This predetermined length is the left and right length of the work end 5 (in FIG. 4, the length from the tip 5a to the broken line displayed on the same surface as the outer surface B). The length of the working end portion 5 is important in that it determines the area of the region that generates frictional heat and prevents the working end portion 5 from being excessively fitted into the inner surface of the bracket slot 11 to improve usability. For example, the width W1 is set in the range of 0.3 mm to 0.4 mm.

  If the height H1 <the height H2 is set, a taper is provided, and insertion is easier. For example, the height H1 = 0.4 mm and the height H2 = 1 mm can be set (see FIG. 4). Since there is no physical limitation on the height H1 and the height H2, for example, if the height H1 = the height H2 = 0.75 mm to 0.8 mm is set, the frictional heat can be efficiently generated. .

  Since the working end portion 5 is formed of stainless steel, which is a highly rigid member having a thickness that vibrates by ultrasonic waves, it vibrates ultrasonically. Here, the vibration frequency is around 30 kHz. The working end portion 5 is coupled to an ultrasonic conduction path including the connecting portion 2, the shaft portion 3, the bending portion 4, and the handle coupling portion 6. Furthermore, an ultrasonic generation portion (not shown) is connected by another ultrasonic conduction path (not shown). Combined with. Then, frictional heat is generated between the inner surface of the bracket slot 11 of the orthodontic bracket 10 and the work end 5 by the vibration of the work end 5. This frictional heat is transmitted from the orthodontic bracket 10 to the adhesive, and the frictional heat softens the adhesive. In this way, the orthodontic bracket 10 can be removed from the teeth. At the time of removal, the orthodontic bracket 10 can be easily removed by vibrating the working end 5 for a time in the range of 3 to 5 seconds to soften the adhesive and sandwiching the orthodontic bracket 10 with tweezers or the like. As shown in the background art, no pliers are used, no large destructive force is applied by the chisel, or the orthodontic bracket 10 is not heated to a high temperature with a large heat source. In this way, when the ultrasonic vibration is stopped without applying a strong external force to the teeth or the contact between the bracket slot 11 and the work end 5 is cut off, the work end 5 is immediately lowered, so the time for maintaining the high temperature is shortened. The effect of ensuring safety is extremely great.

  FIG. 6 is a photograph of the orthodontic bracket and the working end.

  The upper photograph in FIG. 6 is a photograph of the orthodontic bracket, and the lower photograph is a photograph when the working end portion is inserted into the bracket slot of the orthodontic bracket.

  In removing the orthodontic bracket from the teeth, conventionally, a method of tearing off the orthodontic bracket with a pliers, a method of destroying the adhesive with a chisel, a method of putting a high heat iron into the oral cavity, etc. have been proposed. Remove the orthodontic brackets from the teeth in a way that has never been done before. According to the method of the present invention, it is safer and can be used for orthodontic treatment in a short time without the need for special techniques from moving teeth, deciduous teeth, treated teeth, or teeth of elderly people with weak surfaces. The bracket can be removed and the effect is great, and the present invention has high industrial applicability.

  The present invention is not limited to the embodiment described above. Embodiments that can be implemented by combining the elements of the above-described embodiments are also included, and of course, embodiments that have the same technical idea as these are also included in the present invention.

DESCRIPTION OF SYMBOLS 1 Orthodontic bracket removal tool 2 Connecting part 3 Shaft part 4 Bending part 5 Working end part 6 Handle coupling part 7 Liquid ejection hole 10 Orthodontic bracket 11 Bracket slot

Claims (3)

An orthodontic bracket removing tool for removing an orthodontic bracket bonded to a tooth by an adhesive from the tooth,
Comprising an ultrasonic conduction path for guiding ultrasonic waves to the working end of the orthodontic bracket removing tool;
The working end is formed by a highly rigid member that vibrates by the ultrasonic waves, and is shaped to fit into a bracket slot provided in the orthodontic bracket,
Friction heat is generated between the working end and the bracket slot forming surface of the orthodontic bracket by the vibration of the working end,
Transferring the frictional heat from the orthodontic bracket to the adhesive;
The frictional heat transferred to the adhesive softens the adhesive and allows the orthodontic bracket to be removed from the teeth;
Orthodontic bracket removal tool. The vertical length of the working end is
The closer to the tip of the working end, the shorter it becomes,
Equal to the vertical length of the bracket slot at a position away from the tip of the working end by a predetermined length;
The orthodontic bracket removing tool according to claim 1, wherein a cross section of the working end is a rectangle having rounded corners. The orthodontic bracket removal tool is:
A connecting portion that can be gripped by hand to control the position of the working end with respect to the bracket slot;
A handle coupling part disposed at one end of the coupling part and attachable to and detachable from the ultrasonic wave generating part;
A curved portion that facilitates fitting the working end into the bracket slot of the orthodontic bracket;
A shaft portion that couples one end of the curved portion to the other end of the connecting portion;
The working end to which the other end of the bending portion is coupled,
The orthodontic bracket removal tool according to claim 1, wherein the connecting portion, the handle coupling portion, the bending portion, the shaft portion, and the working end portion function as the ultrasonic conduction path.