Dental treatment devices

Abstract

The present invention discloses a dental treatment device, wherein the dental treatment device (10) comprises a file holder (13), a high-frequency signal generating circuit (19), a root canal length measuring circuit (23) and a control circuit (21). The file holder (13) holds a file (11) arranged in a root canal. The high-frequency signal generating circuit (19) supplies a high-frequency current to the file (11). The root canal length measuring circuit (23) electrically measures the position of the front end of the file 11 in the root canal. The control circuit (21) controls the current value of the high-frequency current supplied to the file (11) by the high-frequency signal generating circuit (19) based on the information of the position of the front end of the file (11) measured by the root canal length measuring circuit (23).

Description

Technical Field

[0001] The present invention relates to a dental treatment device for supplying high-frequency current to a dental treatment site. Background Art

[0002] In the dental field, root canal treatment is sometimes performed to remove the dental pulp or to suppress inflammation at the root apex. In conventional root canal treatment, the root canal is cut and enlarged using a reamer or a file, and after removing contaminated tissue or contaminated material in the root canal, a medicine is filled into the root canal.

[0003] However, the shape of the root canal is complex and varies depending on the type of tooth and each person. Therefore, in root canal treatment, there are parts where it is difficult to enlarge the root canal using a reamer or file, and inflammatory factors remain in the parts where the root canal cannot be enlarged, which may cause inflammation after surgery.

[0004] Therefore, Japanese Patent No. 4041165 discloses a dental medical device for applying high-frequency electronic pulses to the inside of a root canal. In this medical device, a needle-shaped electrode (such as a file) is inserted into the root canal, and when the tip of the needle reaches the root apex, a high-frequency electronic pulse is applied to cauterize the pulp.

[0005] In addition, International Publication No. 2008 / 114244 discloses a dental treatment device for performing root canal treatment for reducing inflammatory factors, bacteria, etc. in the root canal of a tooth. In the dental treatment device, a dental instrument that communicates with a measuring device that measures the position of the root apex includes an electrode inserted into the root canal. Furthermore, the dental instrument can communicate with a unit that applies electronic pulses. Therefore, the dental treatment device can apply electronic pulses to the root canal via the electrode inserted into the root canal, thereby reducing inflammatory factors, bacteria, etc. in the root canal by the applied electronic pulses. Summary of the invention

[0006] The treatment targets of root canal treatment include hard tissues such as teeth and soft tissues such as granulation tissues. Even if the high-frequency current of the same current value is applied, pain may be felt in the soft tissues where nerves are present. In particular, there are many soft tissues near the root apex, so it is necessary to be more careful when applying high-frequency current than other parts. In addition, generally speaking, the closer the electrode is to the root apex, the more careful the operation requires. When applying high-frequency current, it is necessary to apply the current at the optimal current value or change the current according to the position of each electrode.

[0007] However, in the dental treatment device involved in International Publication No. 2008 / 114244, only a structure is disclosed in which an electronic pulse is automatically sent to the root canal via the electrode when the electrode reaches a predetermined position. Therefore, depending on the position of the electrode in the root canal, pain caused by the energization may sometimes be felt. In addition, in order to alleviate the pain caused by the energization, anesthesia is also considered, but when anesthesia is performed during dental treatment, it takes about 10 to 15 minutes until the anesthesia takes effect, which reduces the treatment efficiency. Furthermore, since the energization is not performed at the optimal current value or the energized current is not changed according to the position of the electrode in the root canal, it is possible to damage the important tissue at the apex.

[0008] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a dental treatment device that can supply a high-frequency current of an optimal current value to an electrode inserted into a root canal without reducing treatment efficiency.

[0009] The dental treatment device disclosed herein passes a high-frequency current through a root canal. The dental treatment device includes a holding portion, a power supply portion, a root canal length measuring portion, and a control portion. The holding portion holds an electrode disposed in the root canal. The power supply portion passes a high-frequency current through the electrode. The root canal length measuring portion electrically measures the position of the front end of the electrode in the root canal. The control portion controls the current value of the high-frequency current that passes through the electrode on the power supply portion based on information on the position of the front end of the electrode measured by the root canal length measuring portion.

[0010] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 An external view of the dental treatment device according to the first embodiment is shown.

[0012] Figure 2 This is a block diagram showing the configuration of the dental treatment device according to the first embodiment.

[0013] Figure 3 A simplified diagram illustrating the root canal of a tooth.

[0014] Figure 4 This is a flowchart for explaining control of the dental treatment device according to the second embodiment.

[0015] Figure 5 This is a flowchart for explaining the control of the sterilization mode of the dental treatment device involved in the second embodiment.

[0016] Figure 6This is a diagram showing the waveform of the current supplied to the electrodes of the dental treatment device according to the second embodiment.

[0017] Figure 7 This is a diagram showing the waveform of the current flowing through the electrodes of the dental treatment device according to the modification of the second embodiment.

[0018] Figure 8 This is a flowchart for explaining the control of the sterilization mode of the dental treatment device involved in the third embodiment.

[0019] Fig. 9 This is a diagram showing the waveform of the current supplied to the electrodes of the dental treatment device according to the third embodiment.

[0020] Fig.10 This is a flowchart for explaining the control of the sterilization mode of the dental treatment device involved in the fourth embodiment. DETAILED DESCRIPTION

[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0022] (Implementation Method 1)

[0023] Figure 1 An external view of the dental treatment device according to the first embodiment is shown. Figure 2 This is a block diagram showing the configuration of the dental treatment device according to the first embodiment. Figure 3 This is a simplified diagram for explaining the root canal of a tooth. The degree of curvature of the root canal, the condition of calcification and occlusion of the root canal, etc. vary from person to person, and root canal treatment, which involves cutting and enlarging the root canal of a tooth, is a very difficult treatment. Figure 3 The tooth 900 shown is a molar, and one tooth includes a plurality of root canals 901. It is difficult to treat all of such a complex root canal. In particular, when there is a portion where it is difficult to cut and enlarge the root canal using a cutting tool such as a reamer or a file, and the root canal cannot be cut and enlarged in this portion and dental pulp and inflammatory factors remain in the root canal, inflammation may occur after surgery.

[0024] Therefore, in the dental treatment device, an electrode is inserted into the inside of the root canal and a high-frequency current is applied to the electrode for treatment. This treatment is to apply a high-frequency current to the human body, especially teeth, especially the root canal, periodontal tissue, and bone, so that the energized parts, especially the parts near the electrode and the parts with high current density are burned by the Joule heat generated by the high-frequency current, thereby reducing inflammatory factors, bacteria, etc. It should be noted that this treatment can be used even if it cannot completely kill bacteria, as long as it can cause the pulp and granulation to be thermally denatured and necrotic and inactivated. In addition, this treatment is also called EMAT (Electro-Magnetic Apical Treatment), which is disclosed in the literature (for example, Naoki Bando, Toshihiko Tominaga, Hiromichi Yumoto, Takashi Sumitomo, Hayaki Hirao, Koji Hirao, Keiji Matsuo, "Application of Electromagnetic Wave Irradiation in Endodontic Therapy-EMAT (Electro-Magnetic Apical Treatment)", 2011, Journal of Endodontic Therapy, Vol. 32, p. 184-200). This publication reports that by passing a high-frequency current through the affected area before and after treatment, inflammatory factors, bacteria, etc. in the dental treatment area can be reduced, and the prognosis is extremely good.

[0025] However, the treatment targets of root canal treatment include hard tissue parts such as teeth and soft tissue parts such as granulation tissues. Even if high-frequency current of the same current value is applied, pain may be felt in the soft tissue parts where nerves exist. In particular, there are many parts and soft tissue parts near the root apex where clinically large thermal damage is not desired, so it is necessary to be more careful when applying high-frequency current compared to other parts.

[0026] In order to reduce the pain caused by the electric current, anesthesia can be administered. However, when anesthesia is administered during dental treatment, it takes about 10 to 15 minutes including the operation time until the anesthesia takes effect, which reduces the treatment efficiency.

[0027] Furthermore, since the closer the electrode is to the root apex, the more careful the operation requires. Therefore, in the dental treatment device 10 involved in the first embodiment, the possibility of damaging the important root apex tissue is reduced by supplying electricity at an optimal current value according to the position of each electrode, or by changing or stopping the current supplied. Figure 1 As shown, the dental treatment device 10 includes a file 11 (see Figure 2) a unit 12 for passing high-frequency current and a file holder 13 for holding the file 11, and the high-frequency current can be passed to the file 11 mounted at the front end of the file holder 13. It should be noted that in the present disclosure, the case where the file 11 is mounted at the front end of the file holder 13 and the file 11 is an electrode arranged in the root canal is described, but the file holder 13 and the file 11 may be integrated into one structure.

[0028] The file holder 13 is formed of a substantially rod-shaped frame body and can hold the metal part of the file 11. The file holder 13 can electrically connect the file to the unit 12 by holding the metal part of the file 11. The unit 12 is provided with a display unit 14 and a setting operation unit 15, and is connected to a foot switch 16 and a passive electrode 22.

[0029] like Figure 2 As shown, the unit 12 is provided with a high-frequency signal generating circuit 19, a detecting unit 20, a control circuit 21, a root canal length measuring circuit 23, and switches SW1 and SW2 in addition to the display unit 14 and the setting operation unit 15. Then, the unit 12 measures the position of the front end of the file 11 through the root canal length measuring circuit 23, and supplies a high-frequency current of a current value corresponding to the information of the measured position to the file 11. Specifically, Figure 3 As shown in FIG. 1 , if the position of the tip of the file 11 protrudes from the root apex by more than 2 mm (≤+2 mm), the unit 12 sets the current value of the file 11 to 0 mA (that is, stops the current). Figure 3 As shown in FIG. 1 , if the position of the tip of the file 11 protrudes from the root apex by less than 2 mm (+2 mm to 0 mm), the unit 12 sets the current value of the file 11 to 40 mA to 60 mA. Figure 3 As shown in FIG. 1 , if the position of the tip of the file 11 is within a range of 2 mm from the root apex toward the crown side (0 mm to -2 mm), the unit 12 pre-sets the current value of the file 11 to 60 mA to 80 mA. Figure 3 As shown in FIG. 1 , if the position of the tip of the file 11 is within the range of -2 mm to -4 mm from the root apex toward the crown side, the unit 12 pre-sets the current value of the file 11 to 80 mA to 90 mA. Figure 3 As shown, if the position of the tip of the file 11 is greater than -4 mm from the apex toward the crown side, the unit 12 sets the current value for energizing the file 11 to greater than 90 mA in advance.

[0030] exist Figure 3, an example is shown in which the current value of the unit 12 for energizing the file 11 is pre-set according to the distance from the root apex to the position of the tip of the file 11. These positions are actually indicated by the output of the root canal length measuring device, and are not limited to this. The unit 12 pre-sets the current value for energizing the file 11 according to the signal of the tip of the file 11 measured by the root canal length measuring circuit 23 or the instrument value of the root canal length measuring circuit 23. Furthermore, the unit 12 may have a function of sequentially adjusting the current value for energizing the file 11 to be the current value pre-set according to the position of the tip of the file. Of course, the unit 12 may also have a function of stopping energizing the file 11 when the current value for energizing the file 11 deviates from the pre-set current value.

[0031] Hereinafter, the configuration and control of the means 12 for supplying electricity at an optimum current value or changing the supplied current based on the information on the position of the tip of the file 11 will be described in detail.

[0032] The setting operation unit 15 is a setting button provided for setting the operation of the dental treatment device 10. In the setting operation unit 15, the current value, frequency, power-on period, display setting of the display unit 14, etc. of the high-frequency current for energizing the file 11 corresponding to the position of the front end of the file 11 can be set. Of course, these parameters are preset and can also be changed. Here, the power-on period is the time of one power-on when the high-frequency current is energized once by one operation, and is the sum of the times of multiple power-ons when the high-frequency current is energized multiple times by one operation.

[0033] The foot switch 16 is an operation unit for operating the high frequency current. When the user steps on the foot switch 16, the control circuit 21 sends a control signal to the high frequency signal generating circuit 19. The high frequency signal generating circuit 19 energizes the file 11 with the high frequency current set by the setting operation unit 15 according to the received control signal.

[0034] The high-frequency signal generating circuit 19 supplies a high-frequency current, for example, of a frequency of 300kHz to 1000kHz and a current value of 20mA to 200mA (a range of current values ​​required for root canal treatment to reduce inflammatory factors, bacteria, etc. in the root canal) between the file 11 and the passive electrode 22. Of course, the high-frequency current that can be generated by the high-frequency signal generating circuit 19 is not limited to the above-mentioned frequency and current value. The current value, frequency, power-on period, etc. of the high-frequency current output from the high-frequency signal generating circuit 19 can be set and changed by operating the setting operation unit 15. The control circuit 21 controls the high-frequency signal generating circuit 19 according to the current value detected by the detection unit 20 so that the high-frequency signal generating circuit 19 can output the current value of the high-frequency current set by the setting operation unit 15. However, if the control circuit 21 does not control the high-frequency signal generating circuit 19 according to the current value detected by the detection unit 20, the detection unit 20 may not be provided in the dental treatment device 10. When the high-frequency current is applied, the file 11 is inserted into the root canal 901, and its front end contacts the tissue near the root apex 903, for example, and the passive electrode 22 contacts a part of the patient's body such as the gum 902 or the lip 904. That is, the file holder 13 is a holding portion that holds the file 11 as an electrode arranged in the root canal 901, and the high-frequency signal generating circuit 19 is a power supply portion that applies the high-frequency current to the electrode.

[0035] The detection unit 20 is a current detector that detects the current value actually flowing through the file 11 when the high-frequency current is supplied to the file 11 from the high-frequency signal generating circuit 19. The control circuit 21 controls the current value of the high-frequency current supplied to the file 11 by the high-frequency signal generating circuit 19 based on the information of the position of the tip of the file 11 measured by the root canal length measuring circuit 23. For example, the control circuit 21 predetermines the optimal current value predetermined by the setting operation unit 15 based on the information of the position of the tip of the file 11 as a data table, and sends a control signal of the current value of the high-frequency current to the high-frequency signal generating circuit 19 according to the data table. In addition, the operator can also change the information of the position of the tip of the file 11 and the setting of the optimal current value predetermined in the data table. As a hardware structure, the control circuit 21 is provided with, for example, a CPU (Central Processing Unit), a storage unit storing programs or data for the CPU to execute the processing, a RAM (Random Access Memory) functioning as a work area of ​​the CPU, a GPU (Graphics Processing Unit) mainly performing image processing, an input / output interface for maintaining the compatibility of signals with peripheral devices, etc. The storage unit includes a storage device such as a non-volatile memory provided inside the control circuit 21, a storage device connected via a network, etc.

[0036] The root canal length measuring circuit 23 flows a root canal length measuring signal between the file 11 and the passive electrode 22 to measure the position of the tip of the file 11. The information on the position of the tip of the file 11 measured by the root canal length measuring circuit 23 is sent from the root canal length measuring circuit 23 to the control circuit 21. Specifically, the root canal length measuring circuit 23 applies two voltages of different frequencies between the file 11 and the passive electrode 22 to obtain the values ​​of the impedances of each, and determines the position of the tip of the file 11 from the root apex 903 based on the difference or ratio of the two values ​​(actually, the values ​​of the voltage or current corresponding to the impedance values). The root canal length measuring method is not limited to this method, and various techniques including the measuring methods proposed in the past can be used. When measuring the root canal length, the passive electrode 22 is also in contact with a part of the patient's body such as the gums 902 or the lips 904.

[0037] The switch SW1 is provided to switch the electrical connection between the file 11 and the high frequency signal generating circuit 19 or the root canal length measuring circuit 23. The switch SW2 is provided to switch the electrical connection between the passive electrode 22 and the high frequency signal generating circuit 19 or the root canal length measuring circuit 23.

[0038] The switch SW1 and the switch SW2 are switched by the control circuit 21 according to the input information from the setting operation unit 15. Specifically, when the high-frequency current is supplied to the file 11, the control circuit 21 controls the switch SW1 and the switch SW2 so that the file 11 and the passive electrode 22 are connected to the high-frequency signal generating circuit 19. In addition, when the root canal length measuring signal flows between the file 11 and the passive electrode 22, the control circuit 21 controls the switch SW1 and the switch SW2 so that the file 11 and the passive electrode 22 are connected to the root canal length measuring circuit 23. In the first embodiment, the switch SW1 and the switch SW2 are controlled according to the operation mode set by the setting operation unit 15 to switch the connection destination of the file 11 and the passive electrode 22. In addition, the switching of the switch SW1 and the switch SW2 may be linked to the on / off operation of the foot switch 16.

[0039] In the first embodiment, the high-frequency signal generating circuit 19 is electrically separated from the root canal length measuring circuit 23 by the switch SW1 and the switch SW2. Therefore, while the high-frequency current is output to the file 11, the root canal length measuring circuit 23 is electrically disconnected from the file 11 and the passive electrode 22 by the switch SW1 and the switch SW2. Therefore, the high-frequency current is not supplied to the root canal length measuring circuit 23, and the root canal length measuring circuit 23 can be prevented from malfunctioning due to the high-frequency current.

[0040] In the first embodiment, the position of the tip of the file 11 from the root apex can be known by the root canal length measuring circuit 23, and the information of the position of the tip of the file 11 is sent to the control circuit 21. Therefore, after the user confirms the position of the tip of the file 11, the operation mode of the dental treatment device 10 is switched from the root canal length measuring mode to the sterilization mode (also called the high-frequency energizing mode), and the high-frequency current of the optimal current value at the position is energized to the file 11. In addition, the dental treatment device 10 may receive the information of the position of the tip of the file 11 measured by the root canal length measuring device provided in another housing, and energize the file 11 with the high-frequency current based on the information, without providing the root canal length measuring circuit 23 in the housing. In addition, as an example of display, when the operation mode is the root canal length measurement mode, the dental treatment device 10 functions as a root canal length measuring device and displays the position of the tip of the file 11 on the display unit 14, but when the operation mode is the sterilization mode, it functions as a high-frequency treatment device and displays the current value of the high-frequency current being energized on the display unit 14. That is, the display unit 14 functions as a high-frequency current measuring device when the operation mode is the sterilization mode, and can notify the user of the current value of the high-frequency current being energized in real time, thereby cultivating the user's intuition during treatment. In addition, when the information on the position of the tip of the file 11 in the root canal measured changes by more than a predetermined ratio due to the energization, the control circuit 21 may also regard that the root canal environment has changed due to the energization, and display information indicating that the position of the tip of the file 11 has changed sharply on the display unit 14.

[0041] The display unit 14 is composed of, for example, a liquid crystal display, and displays the current value of the file 11 supplied by the high-frequency signal generating circuit 19, the position of the tip of the file 11 measured by the root canal length measuring circuit 23, and the like, and functions as a notification unit that notifies the user of the dental treatment device 10 of the required information. For example, when the current value detected by the detection unit 20 is outside the range of the current value required for the root canal treatment for reducing the inflammatory factors, bacteria, etc. in the root canal, the display unit 14 may notify the user of the information that the current value of the high-frequency current being supplied is outside the range of the current value required for the root canal treatment. In addition, the display unit 14 may also be composed of an organic EL display, electronic paper, a light-emitting diode, or the like. In addition, the notification unit may be a lamp, a speaker, or the like, which is not shown, other than the display unit 14, and the user may be notified by lighting the lamp or by outputting a buzzer sound from the speaker.

[0042] Thus, the dental treatment device 10 according to the first embodiment is a dental treatment device for passing a high-frequency current through a root canal. The dental treatment device 10 includes: a file holder 13 for holding a file 11 disposed in a root canal; a high-frequency signal generating circuit 19 for passing a high-frequency current through the file 11; a root canal length measuring circuit 23 for electrically measuring the position of the tip of the file 11 in the root canal; and a control circuit 21 for controlling the current value of the high-frequency current passed through the file 11 by the high-frequency signal generating circuit 19 based on information on the position of the tip of the file 11 measured by the root canal length measuring circuit 23.

[0043] By configuring in this way, in the dental treatment device 10 involved in Embodiment 1, the high-frequency signal generating circuit 19 controls the current value of the high-frequency current for energizing the file 11 based on the information of the position of the front end of the file 11 measured by the root canal length measuring circuit 23. Therefore, a high-frequency current of an optimal current value corresponding to the information of the position of the front end of the file 11 inserted into the root canal can be energized, thereby improving the treatment efficiency.

[0044] Furthermore, the control circuit 21 may control the high-frequency signal generating circuit 19 to not start the high-frequency current supply to the file 11, to stop the high-frequency current supply to the file 11, or to change the current value of the supply, based on the information of the position of the tip of the file 11 in the root canal. Thus, the dental treatment device 10 can perform the best control such as stopping the supply of high-frequency current when the tip of the file 11 is outside the root canal. On the contrary, when the tip of the file moves toward the crown side, the current value automatically increases. In addition, the control of not starting the supply of high-frequency current to the file 11 means that the supply of high-frequency current to the file 11 is not started even if the operator performs the supply operation under the control before the supply of high-frequency current to the file 11 is performed. On the other hand, the control of stopping the supply of high-frequency current to the file 11 is the control of the period of supply of high-frequency current to the file 11. During the stop, the root canal length measurement may be performed, and the supply of high-frequency current to the file 11 is not performed during the stop.

[0045] The control circuit 21 has a root canal length measurement mode (first control mode) and a sterilization mode (second control mode). The root canal length measurement mode is a mode in which the root canal length measurement circuit 23 is controlled to pass a measurement signal to the file 11 to electrically measure the position of the tip of the file 11 in the root canal. The sterilization mode (second control mode) is a mode in which the high-frequency signal generating circuit 19 is controlled to pass a high-frequency current to the file 11. Thus, the dental treatment device 10 can suppress the root canal length measurement circuit 23 from malfunctioning due to the high-frequency current by switching between the root canal length measurement mode and the sterilization mode. For example, the control circuit 21 further includes a foot switch 16 (operating unit) for accepting a user's operation. When the control circuit 21 accepts a user's operation through the foot switch 16, it switches the control of the high-frequency signal generating circuit 19 to the sterilization mode.

[0046] The control circuit 21 may also control the high-frequency signal generating circuit 19 as follows: in the root canal length measuring mode, the position of the tip of the file 11 in the root canal is measured, and in the sterilization mode, a current value within a predetermined range set according to the measured position of the tip of the file 11 is supplied to the file 11. Thus, the dental treatment device 10 can control the current value of the high-frequency current supplied to the file 11 within a predetermined range.

[0047] The control circuit 21 may cause the display unit 14 to display the measured position of the tip of the file 11 in the root canal. Thus, the dental treatment apparatus 10 can inform the user of the position of the tip of the file 11.

[0048] Furthermore, the dental treatment device 10 further includes a display unit 14 for notifying the user of information. The control circuit 21 may also display on the display unit 14 whether the control is being performed in the root canal length measurement mode or the sterilization mode. Thus, the dental treatment device 10 can inform the user of the operation mode during operation.

[0049] When the position of the tip of the file 11 in the root canal measured satisfies a prescribed condition, the control circuit 21 causes the display unit 14 to notify information indicating that the prescribed condition is satisfied. When the position of the tip of the file 11 in the root canal measured changes by a prescribed ratio or more as a prescribed condition, the control circuit 21 causes the display unit 14 to notify information indicating that the position of the tip of the file 11 has changed abruptly. In addition, when the current value detected by the detection unit 20 is outside the prescribed range, the control circuit 21 causes the display unit 14 to notify information indicating that the current value of the high-frequency current being supplied is outside the prescribed range. Thus, the dental treatment device 10 can appropriately notify the user of the status of the high-frequency current being supplied.

[0050] (Implementation Method 2)

[0051] In the first embodiment, a dental treatment device 10 is described in which a high-frequency current of a preset current value is supplied to the file 11 in the sterilization mode based on information on the position of the tip of the file 11 measured in the root canal length measurement mode. In the second embodiment, control of the current value of the high-frequency current supplied to the file 11 in the sterilization mode is described in detail. In addition, in the second embodiment, the same reference numerals are attached to the same structures as those of the dental treatment device 10 described in the first embodiment, and the detailed description is not repeated. In addition, the contents described in the first embodiment can be combined with the second embodiment within the range that there is no contradiction.

[0052] Control of the current value of the high-frequency current supplied to the file 11 in the dental treatment device 10 will be described using a flowchart. Figure 4 This is a flowchart for explaining control of the dental treatment device according to the second embodiment. Figure 5 1 is a flowchart for explaining the control of the sterilization mode of the dental treatment device according to Embodiment 2. First, the user causes the dental treatment device 10 to operate in the root canal length measurement mode. The control circuit 21 executes the root canal length measurement mode as the operation mode (step S10). The control circuit 21 notifies the display unit 14 of information indicating that the root canal length measurement mode is executed to notify the user of the executed operation mode (step S11).

[0053] The control circuit 21 instructs the root canal length measuring circuit 23 to measure the position of the front end of the file 11 (step S12). The root canal length measuring circuit 23 starts the root canal length measurement according to the control signal from the control circuit 21, and flows a root canal length measuring signal between the file 11 and the passive electrode 22 to measure the position of the front end of the file 11. The control circuit 21 determines whether to change the operation mode to the sterilization mode (step S13). For example, the control circuit 21 determines whether to change the operation mode to the sterilization mode according to whether the user operates the foot switch 16. Specifically, the control circuit 21 determines that the operation mode is changed to the sterilization mode when the user operates the foot switch 16, and determines that the operation mode is maintained in the root canal length measuring mode when the user does not operate the foot switch 16.

[0054] When it is determined that the operation mode is not to be changed to the sterilization mode ("No" in step S13), the control circuit 21 determines whether an operation to end the root canal length measurement mode is accepted (step S14). When an operation to end the root canal length measurement mode is not accepted ("No" in step S14), the control circuit 21 returns the process to step S12 and continues to execute the root canal length measurement mode. On the other hand, when an operation to end the root canal length measurement mode is accepted ("Yes" in step S14), the control circuit 21 ends the execution of the root canal length measurement mode.

[0055] Returning to step S13, when it is determined that the operation mode is changed to the sterilization mode ("Yes" in step S13), the control circuit 21 notifies the display unit 14 of the information indicating the execution of the sterilization mode to notify the user of the executed operation mode (step S15). The control circuit 21 displays the operation mode executed in step S15 and starts the processing of the sterilization mode.

[0056] Next, according to Figure 5 The control circuit 21 determines the voltage value of the high frequency signal generating circuit 19 for energizing the file 11 to a high frequency current value within a predetermined range based on the information of the position of the tip of the file 11 received from the root canal length measuring circuit 23 (step S101).

[0057] The control circuit 21 counts the number of times the high-frequency current is energized during the energization period by adding 1 to the count of the energization times counter (step S102). The control circuit 21 controls the high-frequency signal generating circuit 19 to energize the file 11 with a current value within a specified range from the high-frequency signal generating circuit 19 by applying the voltage value determined in step S101 to the high-frequency signal generating circuit 19 during the energization period (step S103). After the energization period, the control circuit 21 stops energizing the file 11 from the high-frequency signal generating circuit 19 during the rest period (step S104). The control circuit 21 determines whether the current value detected by the detection unit 20 when the voltage value determined in step S101 is applied to the high-frequency signal generating circuit 19 is a current value within a specified range (step S105).

[0058] When the detected current value is within the specified range ("Yes" in step S105), the control circuit 21 determines whether the power-on counter is N times (for example, 10 times) or more (step S106). When the power-on counter is not N times or more ("No" in step S106), the control circuit 21 returns the process to step S102 and repeatedly performs the control of the power-on period and the rest period. On the other hand, when the power-on counter is N times or more ("Yes" in step S106), the control circuit 21 resets the power-on counter to 0 (zero) (step S107), and stops the process of passing the high-frequency current to the file 11.

[0059] Returning to step S105, when the detected current value is not within the prescribed range ("No" in step S105), the control circuit 21 displays information indicating that the current value of the high-frequency current being supplied is outside the prescribed range on the display unit 14 (step S110). Specifically, when foreign matter in the root canal falls off while the high-frequency current is supplied to the file 11 near the root apex, and the current value detected by the detection unit 20 changes from the prescribed range (40mA to 60mA) near the root apex to 60mA, 90mA, or 80mA, the control circuit 21 may display a text "outside the prescribed range" on the display unit 14, or change the background color of the screen to yellow, etc. In the case where a speaker is provided as a notification unit, the user may be notified of the information indicating that the current value of the high-frequency current being supplied is outside the prescribed range by a warning sound.

[0060] Next, the control circuit 21 determines whether the current value detected by the detection unit 20 is smaller than the minimum current value within the prescribed range even when the voltage value determined in step S101 is applied to the high-frequency signal generating circuit 19 (step S111). When the detected current value is outside the prescribed range ("No" in step S105) and smaller than the minimum current value within the prescribed range ("Yes" in step S111), the control circuit 21 displays a message on the display unit 14 indicating that the high-frequency current needs to be supplied to the file 11 again (step S112). Specifically, the control circuit 21 may display the text "Power on again" on the display unit 14, or change the background color of the screen to yellow and flash, etc. In the case where a speaker is provided as a notification unit, the user may be notified of the need to supply power again by a warning sound.

[0061] Furthermore, the control circuit 21 counts the energization period during which the detected current value is less than the minimum current value within the prescribed range (step S113). Figure 5In the flowchart shown, the process of applying high-frequency current to the file 11 is not stopped at the time when the detected current value becomes smaller than the minimum current value within the prescribed range, but is stopped after the control of the power-on period and the rest period is repeated N times (for example, 10 times). Therefore, the control circuit 21 can count the power-on period less than the minimum current value according to how many times the power-on period in which the detected current value is less than the minimum current value within the prescribed range occurs in the number of repetitions N times. By counting the power-on period less than the minimum current value, the control circuit 21 only needs to re-energize during the period counted in step S113 when energizing again. Of course, in the case where the process of applying high-frequency current to the file 11 is stopped at the time when the detected current value becomes smaller than the minimum current value within the prescribed range, the control circuit 21 may transfer the process to the process of step S107 after step S113. Here, the case where it can be determined that the detected current value is less than the minimum current value within the prescribed range means that the environment in the root canal changes during energization, the impedance of the root canal becomes high, and a current value less than the minimum current value within the prescribed range flows. In addition, when the detected current value is smaller than the minimum current value within the specified range, the control circuit 21 may increase the voltage applied to the high-frequency signal generating circuit 19 so that the current value of the high-frequency current supplying power to the file 11 becomes greater than the minimum current value within the specified range.

[0062] Returning to step S111, when the detected current value is outside the prescribed range ("No" in step S105) and is not less than the minimum current value in the prescribed range ("No" in step S111), the control circuit 21 can determine that the detected current value is greater than the maximum current value in the prescribed range, and therefore, stop the process of passing high-frequency current to the file 11 (step S115). The control circuit 21 displays the information that the process of passing high-frequency current to the file 11 has been stopped on the display unit 14 (step S116). Specifically, the control circuit 21 can consider displaying the word "stop" on the display unit 14, or changing the background color of the screen to red and flashing, etc. In the case where a speaker is provided as a notification unit, the user can also be notified of the information that the power supply has been stopped by using a warning sound. Here, the case where the detected current value is judged to be greater than the maximum current value within the prescribed range means that the environment in the root canal changes when power is applied, the impedance of the root canal becomes low, and a current value greater than the maximum current value within the prescribed range flows, or the impedance of the root canal is low from the beginning when power is applied for the first time, etc. In addition, when the detected current value is greater than the maximum current value within the prescribed range, the control circuit 21 may control the current value of the high-frequency current applied to the file 11 to be less than the maximum current value within the prescribed range by reducing the voltage applied to the high-frequency signal generating circuit 19.

[0063] Next, the waveform of the high-frequency current supplied from the high-frequency signal generating circuit 19 to the file 11 will be described. Figure 6 1 is a diagram showing the waveform of the current applied to the electrode of the dental treatment device according to Embodiment 2. When the user operates the foot switch 16 at the high-frequency current application position according to the display of the root canal length measuring circuit 23, the dental treatment device 10 is Figure 6 In the waveform shown, a high-frequency current having a current value corresponding to the energizing position is supplied from the high-frequency signal generating circuit 19 to the file 11 .

[0064] exist Figure 6 During the power-on period (TP) shown, a high-frequency current corresponding to the position of the tip of the file is supplied from the high-frequency signal generating circuit 19 within the current value range (e.g., 30 mA to 80 mA) required for root canal treatment to reduce inflammatory factors, bacteria, etc. in the root canal. Figure 6 The figure shown is a conceptual diagram, and the wave number shown in the figure is different from the actual high frequency wave number. The same is true for the high frequency waveform below. That is, the control circuit 21 supplies high frequency current to the file 11 from the high frequency signal generating circuit 19 during the power-on period at the optimal current value predetermined based on the information on the position of the front end of the file 11.

[0065] The high-frequency signal generating circuit 19 is energized for, for example, 0.07 seconds (70 ms) as a power-on period, and then is de-energized for, for example, 0.03 seconds (30 ms) as a rest period (TC). Furthermore, the high-frequency signal generating circuit 19 repeats the second period and the rest period (a total of 0.1 seconds (100 ms)) N times (for example, 10 times) for one power-on (for example, one operation of the foot switch 16). In the dental treatment device 10, when the user steps on the foot switch 16 once, the high-frequency signal generating circuit 19 energizes the file 11 with a high-frequency current for about 1 second (including the rest period). In the second embodiment, the total period in which the second period and the rest period are repeated N times (for example, 10 times) is also referred to as the power-on period. In addition, the number of repetitions of the second period and the rest period can be set in advance by the user using the setting operation unit 15, and is set to 10 times in the second embodiment, for example. Of course, the number of repetitions of the second period and the rest period can also be set to a value other than 10 times. Furthermore, in the setting operation unit 15 , the number of repetitions of the second period and the rest period may be set instead of the number of repetitions of the second period and the rest period, and the energization period (for example, 1 second) may be set.

[0066] The high-frequency signal generating circuit 19 may also perform feedback control to maintain the current value of the high-frequency current determined in step S101 during the power-on period. Specifically, the high-frequency signal generating circuit 19 includes a constant voltage circuit and performs constant voltage control to control the high-frequency voltage applied during the second period according to the current value detected by the detection unit 20 when the high-frequency current is supplied to the file 11, thereby controlling the current value of the high-frequency current determined by supplying power to the file 11. Of course, the high-frequency signal generating circuit 19 may also include a constant current circuit and perform constant current control to control the current value of the high-frequency current determined by supplying power to the file 11.

[0067] The control circuit 21 may also control the file 11 to have a current value within a predetermined range by supplying a preliminary current before the current value of the high-frequency current determined in the step S101 of supplying electricity to the file 11 . Figure 7 This is a diagram showing the waveform of the current flowing through the electrodes of the dental treatment device according to the modification of the second embodiment. Figure 7 The energization in the first period (TP1) shown is a preliminary energization. By determining a voltage that can obtain a current value within a predetermined range pre-set according to information on the position of the front end of the file 11 based on the current value obtained during the preliminary energization and outputting the voltage, the high-frequency current determined in step S101 can be energized in the subsequent second period (TP2). When the high-frequency signal generating circuit 19 energizes the file 11 with a high-frequency current by constant voltage control, since a high-frequency voltage lower than the high-frequency voltage applied in the second period is applied in the first period, an excessive current does not flow in the first period that determines the optimal output voltage. As a result, a current value smaller than the current value applied in the second period can be energized in the first period. Of course, there may be no difference between the current value energized in the first period and the current value energized in the second period.

[0068] The control circuit 21 controls the voltage of the high-frequency signal generating circuit 19 so that the current value of the preliminary current is supplied to the file 11, assuming that the path from the file 11 to the passive electrode 22 has the impedance in the normal state. Furthermore, when the preliminary voltage is applied to supply the preliminary current to the file 11 from the high-frequency signal generating circuit 19, and the impedance of the path from the file 11 to the passive electrode 22 changes from the normal state, a difference is generated between the current value detected by the detection unit 20 and the current value of the assumed preliminary current. The impedance of the path from the file 11 to the passive electrode 22 changes depending on the presence or absence of an insulating film formed on the surface of the file 11, the presence or absence of blood or protein adhering to the surface of the file 11, the impedance of the root canal, and the like.

[0069] The control circuit 21 can perform control as follows: by calculating the difference or ratio between the current value of the assumed preparation current and the current value detected by the detection unit 20, a voltage that can obtain a current value within a predetermined range pre-set according to information on the position of the tip of the file 11 is determined, and the voltage is output, so that the current value of the high-frequency current flowing from the high-frequency signal generating circuit 19 to the file 11 during the power-on period of the second period becomes the current value determined in step S101. That is, when the difference between the current value of the assumed preparation current and the current value detected by the detection unit 20 is large, the control circuit 21 controls in such a manner that the voltage applied to the high-frequency signal generating circuit 19 is increased so that the current value of the high-frequency current flowing through the file 11 becomes the current value determined in step S101. On the contrary, when the difference between the current value of the assumed preparation current and the current value detected by the detection unit 20 is small, the control circuit 21 controls in such a manner that the voltage applied to the high-frequency signal generating circuit 19 is decreased so as to become the current value determined in step S101. Furthermore, the control circuit 21 may apply a preliminary voltage from the high-frequency signal generating circuit 19 to the file 11 , calculate a value corresponding to the impedance of the root canal from the current detected by the detecting unit 20 , and determine the voltage to be applied in the subsequent period based on the value.

[0070] When the control circuit 21 performs feedback control on the current value of the high-frequency current during the energization, when the current value detected by the detection unit 20 changes and deviates from the prescribed range, the display unit 14 may display that the current value deviates from the prescribed range. For example, when a foreign body in the root canal falls off while the high-frequency current is being energized to the file 11 near the apex, and the current value detected by the detection unit 20 changes from the fixed range (40 mA to 60 mA) near the apex to 60 mA, 90 mA, and 80 mA, the display unit 14 displays a warning that the current value deviates from the prescribed range. In addition, when the current value detected by the detection unit 20 is within the prescribed range but changes by a prescribed ratio (for example, about ±30%) or more, the display unit 14 may display information that the current value of the high-frequency current being energized has changed sharply. That is, when the current value deviates from the prescribed range, the control circuit 21 may control the voltage applied to the high-frequency signal generating circuit 19 so that the current value of the high-frequency current energizing the file 11 is within the prescribed range.

[0071] As described above, in the dental treatment device 10 according to the second embodiment, the control circuit 21 can also determine a voltage capable of outputting a current value within a specified range set according to the position of the tip based on the current value detected by the detection unit 20, thereby controlling the current value of the high-frequency current that energizes the file 11 through the high-frequency signal generating circuit 19. Thus, the dental treatment device 10 can perform treatment without causing burden or discomfort to the patient.

[0072] The control circuit 21 may also control the high-frequency signal generating circuit 19 to not start supplying high-frequency current to the file 11, stop supplying high-frequency current to the file 11, or change the current value supplied when the current value greater than the maximum current value within the prescribed range is detected by the detection unit 20. Thus, the dental treatment device 10 can perform treatment without causing burden or discomfort to the patient.

[0073] Furthermore, the control circuit 21 may also cause the display unit 14 to notify the user of the stop of the high-frequency current supply when the detection unit 20 detects a current value greater than the maximum current value within the prescribed range and the high-frequency current supply from the high-frequency signal generating circuit 19 to the file 11 has been stopped. Thus, the dental treatment device 10 can easily inform the user of the reason for stopping the high-frequency current supply.

[0074] In addition, the control circuit 21 may also cause the display unit 14 to notify information urging the high-frequency current to be supplied again when the current value detected by the detection unit 20 is less than the minimum current value in the predetermined range. Thus, the dental treatment device 10 can notify the user that the dental treatment site is not sufficiently sterilized.

[0075] In addition, the control circuit 21 may also time the period during which the current value less than the minimum current value in the predetermined range is detected by the detection unit 20, and notify the timed period on the display unit 14. Thus, the dental treatment device 10 can notify the user of the remaining high-frequency current to be supplied to the file 11 to sufficiently sterilize the dental treatment site.

[0076] (Implementation method 3)

[0077] In the first embodiment, a dental treatment device 10 is described in which a high-frequency current of a preset current value is supplied to the file 11 based on information on the position of the tip of the file 11 measured in the root canal length measurement mode. In the dental treatment device according to the third embodiment, a configuration is described in which the supply period of the high-frequency current supplied to the file is controlled based not only on information on the position of the tip of the file 11 measured in the root canal length measurement mode but also on information on the position of the tip of the file 11 measured during the rest period. In the third embodiment, the same reference numerals are given to the same configurations as those of the dental treatment device 10 described in the first embodiment, and detailed descriptions thereof are not repeated. In addition, the contents described in the first embodiment can be combined with the third embodiment within a range that does not contradict each other.

[0078] The control of the energization period of the high-frequency current for energizing the file 11 in the dental treatment device 10 will be described using a flowchart. Figure 81 is a flowchart for explaining the control of the dental treatment device involved in Embodiment 3. Figure 4 As shown in FIG. 1 , the user operates the dental treatment device 10 in the root canal length measurement mode. The processing of steps S10 to S15 is similar to that of Figure 4 The processing shown is the same, so the detailed description will not be repeated.

[0079] Next, the control circuit 21 determines the period of time during which the high-frequency current is supplied to the file 11 based on the information on the position of the tip of the file 11 received from the root canal length measuring circuit 23 (step S101A). Specifically, the control circuit 21 determines the period of time during which the high-frequency current is supplied to the file 11 to be longer when the tip of the file 11 is located far from the root apex, and conversely determines the period of time during which the high-frequency current is supplied to the file 11 to be shorter when the tip of the file 11 is located close to the root apex.

[0080] The control circuit 21 counts the number of times the high-frequency current is supplied during the power-on period by adding 1 to the count of the power-on times counter (step S102). The control circuit 21 controls the high-frequency signal generating circuit 19 to supply the high-frequency current to the file 11 from the high-frequency signal generating circuit 19 during the power-on period determined in step S101A (step S103). After the power-on period, the control circuit 21 stops supplying power to the file 11 from the high-frequency signal generating circuit 19 during the rest period (step S104). During the rest period, the control circuit 21 switches the operation mode from the sterilization mode to the root canal length measurement mode, causes the root canal length measurement circuit 23 to measure the position of the tip of the file 11 in the root canal, and determines the power-on period based on the information of the position of the tip of the file 11 measured (step S104A). In addition, the control circuit 21 may stop supplying the high-frequency current to the file 11 based on the information of the position of the tip of the file 11 measured during the rest period. For example, if the position of the tip of the file 11 measured during the rest period is outside the root canal, the control circuit 21 stops supplying high-frequency current to the file 11. When supplying high-frequency current to the file 11 is stopped based on the information on the position of the tip of the file 11, the dental treatment device 10 displays this fact on the display unit 14 to inform the user that supplying high-frequency current has been stopped.

[0081] Next, the control circuit 21 determines whether the high-frequency current flows into the file 11 and the current value detected by the detection unit 20 is within the specified range (step S105). When the detected current value is within the specified range ("Yes" in step S105), the control circuit 21 determines whether the number of times the power is supplied is N times (for example, 10 times) or more (step S106). When the number of times the power is supplied is not N times or more ("No" in step S106), the control circuit 21 returns the process to step S102, switches the operation mode from the root canal length measurement mode to the sterilization mode, and repeatedly controls the power supply period and the rest period. The control circuit 21 sets a rest period when returning the process to step S101, but it is not shown. On the other hand, when the number of times the power is supplied is N times or more ("Yes" in step S106), the control circuit 21 resets the number of times the power is supplied to 0 (zero) (step S107), and stops the process of supplying high-frequency current to the file 11.

[0082] Returning to step S105 , when the detected current value is not within the prescribed range (“No” in step S105 ), control circuit 21 displays information indicating that the current value of the high-frequency current being supplied is outside the prescribed range on display unit 14 (step S110 ).

[0083] Next, the control circuit 21 determines whether the high-frequency current flows into the file 11 and the current value detected by the detection unit 20 is less than the minimum current value within the prescribed range (step S111). When the detected current value is outside the prescribed range ("No" in step S105) and is less than the minimum current value within the prescribed range ("Yes" in step S111), the control circuit 21 displays a message on the display unit 14 indicating that the high-frequency current needs to be passed through the file 11 again (step S112).

[0084] Furthermore, the control circuit 21 counts the power-on period during which the detected current value is less than the minimum current value within the specified range (step S113). In addition, the control circuit 21 may also control the current value of the high-frequency current that powers the file 11 to be equal to or greater than the minimum current value within the specified range by increasing the voltage applied to the high-frequency signal generating circuit 19 when the detected current value is less than the minimum current value within the specified range.

[0085] Returning to step S111, when the detected current value is outside the prescribed range ("No" in step S105) and is not less than the minimum current value in the prescribed range ("No" in step S111), the control circuit 21 can determine that the detected current value is greater than the maximum current value in the prescribed range, and therefore, stop the processing of the high-frequency current to the file 11 (step S115). The control circuit 21 displays a message indicating that the processing of the high-frequency current to the file 11 has been stopped on the display unit 14 (step S116). In addition, the control circuit 21 can also control in a manner such that the voltage applied to the high-frequency signal generating circuit 19 is reduced when the detected current value is greater than the maximum current value in the prescribed range so that the current value of the high-frequency current to the file 11 becomes less than the maximum current value in the prescribed range.

[0086] Fig. 9 1 is a diagram showing the waveform of the current flowing through the electrodes of the dental treatment device according to the third embodiment. Fig. 9 In addition, the dental treatment device 10 determines the length of the energizing period based on information on the position of the tip of the file 11 measured during the rest period before energizing during the energizing period.

[0087] The dental treatment device 10 is as follows Fig. 9 As shown in FIG. 1 , the period of time during which the high-frequency current is applied to the file 11 is determined each time based on the information of the position of the tip of the file 11 measured during the rest period. Therefore, the period of time during which the high-frequency current is applied to the file 11 is different in each of the first period, the second period, and the third period. That is, in the dental treatment device 10, since the period of time during which the high-frequency current is applied to the file 11 is determined each time based on the information of the position of the tip of the file 11 measured during the rest period. Fig. 9 The waveform shown in the figure supplies a high-frequency current to the file 11, and therefore, the optimal power-on period can be controlled based on the information of the position of the tip of the file 11. Of course, the dental treatment device 10 may also set the sum of the power-on period TP and the rest period TC to a constant value in advance, and perform a DUTY change such as changing the ratio of the power-on period TP to the rest period TC.

[0088] Thus, in the dental treatment device 10 according to the third embodiment, the control circuit 21 controls the high-frequency signal generating circuit 19 to control the period of time during which the high-frequency current of the current value within the predetermined range is supplied to the file 11, based on the information of the position of the tip of the file 11 in the root canal measured. With such a configuration, the dental treatment device 10 according to the third embodiment can supply the high-frequency current to the file 11 during the optimal supply period, based on the information of the position of the tip of the file 11 in the root canal measured.

[0089] In addition, the control circuit 21 may switch the control of the high-frequency signal generating circuit 19 to the root canal length measuring mode during the rest period between the period of energizing the high-frequency current to the file 11 and the period of energizing the high-frequency current to the next time the high-frequency current is energized to the file 11. Thus, the dental treatment device 10 switches to the root canal length measuring mode during the rest period when the high-frequency current is not energized, and controls the root canal length measuring circuit 23 to electrically measure the position of the tip of the file 11 in the root canal, thereby preventing the root canal length measuring circuit 23 from malfunctioning due to the high-frequency current.

[0090] In addition, in embodiment 3, a structure for controlling the energization period of the high-frequency current for energizing the file 11 based on information about the position of the front end of the file 11 measured during the rest period is described, but the structure described in this embodiment may be appropriately combined with a structure for controlling the current value of the high-frequency current for energizing the file 11 based on information about the position of the front end of the file 11.

[0091] (Implementation 4)

[0092] In the first embodiment, a dental treatment device 10 is described in which a high-frequency current of a preset current value is supplied to the file 11 based on information on the position of the tip of the file 11 measured in the root canal length measurement mode. In the dental treatment device according to the fourth embodiment, a structure is described in which at least one of the current value and the supply period of the high-frequency current supplied to the file is controlled based on information on the position of the tip of the file 11 measured in the root canal length measurement mode. In addition, in the fourth embodiment, the same reference numerals are attached to the same structures as those of the dental treatment device 10 described in the first embodiment, and the detailed description is not repeated. In addition, the contents described in the first embodiment can be combined with the fourth embodiment within the range that there is no contradiction.

[0093] The control based on the product of the current value and the energization period of the high-frequency current supplied to the file 11 in the dental treatment apparatus 10 will be described using a flowchart. Fig.10 4 is a flowchart for explaining the control of the dental treatment device involved in the fourth embodiment. Figure 4 As shown in FIG. 1 , the user operates the dental treatment device 10 in the root canal length measurement mode. The processing of steps S10 to S15 is similar to that of Figure 4 The processing shown is the same, so the detailed description will not be repeated.

[0094] Next, the control circuit 21 determines the voltage value and the power-on period of the high-frequency signal generating circuit 19 for energizing the file 11 to a high-frequency current of a current value within a specified range based on the information of the position of the tip of the file 11 received from the root canal length measuring circuit 23 (step S101B). The control circuit 21 can determine at least one of the length of the power-on period and the current value of the high-frequency current energized during the power-on period by determining the value of the product of the current value of the high-frequency current and the power-on period. In addition, the current value of the high-frequency current energized is controlled to be a current value within a specified range. Specifically, in order to sterilize the root canal, it is necessary to energize a high-frequency current of a current value within a specified range during a specified period. For example, by energizing the file 11 with a high-frequency current of 30 mA for 1 second, the root canal can be sterilized. Therefore, the control circuit 21 determines the current value and the power-on period of the high-frequency current required for sterilizing the root canal based on the product of the current value of the high-frequency current determined based on the information of the position of the tip of the file 11 and the power-on period. Of course, the control circuit 21 may determine either the current value or the power-on period of the high-frequency current that is applied to the file 11 based on the product of the current value of the high-frequency current determined based on the information on the position of the tip of the file 11 and the power-on period. For example, the power-on period is predetermined as a predetermined period, and the control circuit 21 determines only the current value of the high-frequency current that is applied to the file 11 based on the product of the detected current value and the power-on period.

[0095] The control circuit 21 counts the number of times the high-frequency current is supplied during the power-on period by adding 1 to the count of the power-on times counter (step S102). The control circuit 21 controls the high-frequency signal generating circuit 19 so that the high-frequency current is supplied to the file 11 from the high-frequency signal generating circuit 19 at the current value and the power-on period determined in step S101B (step S103). After the power-on period, the control circuit 21 stops supplying power to the file 11 from the high-frequency signal generating circuit 19 during the rest period (step S104). The control circuit 21 determines whether the high-frequency current flows into the file 11 and the current value detected by the detection unit 20 is within the specified range (step S105).

[0096] When the detected current value is within the specified range ("Yes" in step S105), the control circuit 21 determines whether the power-on counter is N times (for example, 10 times) or more (step S106). When the power-on counter is not N times or more ("No" in step S106), the control circuit 21 returns the process to step S102 and repeatedly performs the control of the power-on period and the rest period. On the other hand, when the power-on counter is N times or more ("Yes" in step S106), the control circuit 21 resets the power-on counter to 0 (zero) (step S107), and stops the process of passing the high-frequency current to the file 11.

[0097] Returning to step S105 , when the detected current value is not within the prescribed range (“No” in step S105 ), control circuit 21 displays information indicating that the current value of the high-frequency current being supplied is outside the prescribed range on display unit 14 (step S110 ).

[0098] Next, the control circuit 21 determines whether the high-frequency current flows into the file 11 and the current value detected by the detection unit 20 is less than the minimum current value within the prescribed range (step S111). When the detected current value is outside the prescribed range ("No" in step S105) and is less than the minimum current value within the prescribed range ("Yes" in step S111), the control circuit 21 displays a message on the display unit 14 indicating that the high-frequency current needs to be passed through the file 11 again (step S112).

[0099] Furthermore, the control circuit 21 counts the power-on period during which the detected current value is less than the minimum current value within the specified range (step S113). In addition, the control circuit 21 may also control the current value of the high-frequency current that powers the file 11 to be equal to or greater than the minimum current value within the specified range by increasing the voltage applied to the high-frequency signal generating circuit 19 when the detected current value is less than the minimum current value within the specified range.

[0100] Returning to step S111, when the detected current value is outside the prescribed range ("No" in step S105) and is not less than the minimum current value in the prescribed range ("No" in step S111), the control circuit 21 can determine that the detected current value is greater than the maximum current value in the prescribed range, and therefore, stop the processing of the high-frequency current to the file 11 (step S115). The control circuit 21 displays a message indicating that the processing of the high-frequency current to the file 11 has been stopped on the display unit 14 (step S116). In addition, the control circuit 21 can also control in a manner such that the voltage applied to the high-frequency signal generating circuit 19 is reduced when the detected current value is greater than the maximum current value in the prescribed range so that the current value of the high-frequency current to the file 11 becomes less than the maximum current value in the prescribed range.

[0101] Thus, in the dental treatment device 10 according to the fourth embodiment, the control circuit 21 controls the high-frequency signal generating circuit 19 to control at least one of the current value of the high-frequency current that energizes the file 11 and the period of time during which the high-frequency current is energized to the file 11, so as to obtain a value obtained by multiplying the current value determined based on the information of the position of the tip of the file 11 in the root canal measured and the period of time during which the high-frequency current is energized. By configuring in this way, the dental treatment device 10 according to the fourth embodiment can energize the high-frequency current to the file 11 in a manner that obtains a value obtained by multiplying the current value of the information of the position of the tip of the file 11 in the root canal measured and the period of time during which the high-frequency current is energized.

[0102] In the fourth embodiment, the configuration described in the third embodiment may be appropriately combined to control at least one of the current value and the energizing period of the high-frequency current for energizing the file based on information on the position of the tip of the file 11 measured during the rest period.

[0103] (Variation Example)

[0104] The dental treatment device is not limited to the structure having the file holder 13 on which the file 11 is mounted as described in the above embodiment, and capable of measuring the root canal length and passing high-frequency current, but may also be combined with a structure that drives the treatment tool using a motor, a structure that drives the treatment tool using ultrasound, etc.

[0105] Although the embodiments of the present invention have been described, the embodiments disclosed this time should be considered to be illustrative in all aspects and not restrictive. The scope of the present invention is indicated by the claims, and it is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A dental treatment device for passing a high-frequency current through a root canal, characterized in that: have: A holding portion for holding an electrode disposed in the root canal; A power supply unit for supplying high-frequency current to the electrodes; a root canal length measuring unit for electrically measuring the position of the tip of the electrode in the root canal; and a control unit that automatically controls the current value of the high-frequency current that energizes the electrode on the power supply unit based on information on the position of the tip of the electrode measured by the root canal length measuring unit, The control unit has: In a first control mode, the root canal length measuring unit is controlled to electrically measure the position of the tip of the electrode in the root canal by supplying a measurement signal to the electrode; as well as In the second control mode, the power supply unit is controlled to supply a high-frequency current to the electrode.

2. The dental treatment device according to claim 1, characterized in that: The dental treatment device further includes an operation unit that accepts user operations. The control unit switches control of the power supply unit from the first control mode to the second control mode when receiving an operation by a user through the operation unit.

3. The dental treatment device according to claim 1 or 2, characterized in that: The control unit switches from the second control mode to the first control mode during a rest period, wherein the rest period is a period during which the high-frequency current is stopped and two adjacent current-carrying periods included in a plurality of current-carrying periods during which the high-frequency current is carried to the electrodes are separated.

4. The dental treatment device according to claim 1 or 2, characterized in that: The control unit measures the position of the tip of the electrode in the root canal in the first control mode. In the second control mode, the power supply unit is controlled to supply current to the electrode at a current value within a predetermined range set according to the measured position of the tip of the electrode.

5. The dental treatment device according to claim 1 or 2, characterized in that: The dental treatment device further includes a detection unit that detects a current value supplied from the power supply unit to the electrode. The control unit determines a voltage capable of outputting a current value within a predetermined range set according to the position of the tip based on the current value detected by the detection unit, thereby controlling the power supply unit to control the current value of the high-frequency current that energizes the electrode.

6. The dental treatment device according to claim 1 or 2, characterized in that: The control unit controls the power supply unit to perform any one of the following operations: not starting to energize the electrode with high-frequency current, stopping to energize the electrode with high-frequency current, and changing the current value, based on the information of the measured position of the front end of the electrode in the root canal.

7. The dental treatment device according to claim 1 or 2, characterized in that: The dental treatment device further comprises a notification unit for notifying the user of information. The control unit causes the notification unit to notify whether control is performed in the first control mode or in the second control mode.

8. The dental treatment device according to claim 7, characterized in that: When the control unit stops supplying high-frequency current to the electrode based on the information of the measured position of the tip of the electrode in the root canal, the control unit causes the notification unit to notify the notification unit of the stop of supplying high-frequency current.

9. The dental treatment device according to claim 7, characterized in that: When the measured position of the tip of the electrode in the root canal satisfies a predetermined condition, the control unit causes the notification unit to notify information indicating that the predetermined condition is satisfied.

10. The dental treatment device according to claim 9, characterized in that: When the predetermined condition is satisfied that the measured information on the position of the tip of the electrode in the root canal changes by a predetermined ratio or more due to energization, the control unit causes the notification unit to notify information indicating that the position of the tip of the electrode has changed suddenly.

11. The dental treatment device according to claim 5, characterized in that: When the detection unit detects a current value greater than the maximum current value of the specified range, the control unit controls the power supply unit to perform any one of the following operations: not starting to supply high-frequency current to the electrode, stopping to supply high-frequency current to the electrode, and changing the current value.

12. The dental treatment device according to claim 11, characterized in that: The dental treatment device further comprises a notification unit for notifying the user of information. When the current value detected by the detection unit is outside the predetermined range, the control unit causes the notification unit to notify information indicating that the current value of the high-frequency current being supplied is outside the predetermined range.

13. The dental treatment device according to claim 12, characterized in that: When the detection unit detects a current value greater than the maximum current value in the predetermined range and the power supply unit stops supplying the high-frequency current to the electrode, the control unit causes the notification unit to notify that the supply of the high-frequency current has been stopped. When the detection unit detects a current value that is smaller than the minimum current value in the predetermined range, the notification unit is caused to notify information urging the high-frequency current to be supplied again.

14. The dental treatment device according to claim 12, characterized in that: The control unit measures time for which the detection unit detects a current value smaller than a minimum current value in the predetermined range, and causes the notification unit to notify the measured time.

15. The dental treatment device according to claim 1 or 2, characterized in that: The control unit controls the time for which the high-frequency current is supplied to the electrode by the power supply unit based on the information of the measured position of the tip of the electrode in the root canal.

16. The dental treatment device according to claim 1 or 2, characterized in that: The control unit controls at least one of the current value of the high-frequency current that powers the electrode and the time during which the high-frequency current powers the electrode, so that the value becomes the product of the current value determined based on the information of the position of the front end of the electrode in the root canal measured and the time during which the high-frequency current powers on.

17. The dental treatment device according to claim 1 or 2, characterized in that: The dental treatment device further includes a display unit that displays information on the measured position of the tip of the electrode in the root canal.

18. A dental treatment device for applying high-frequency current to a dental treatment site, characterized in that: have: A holding portion for holding an electrode disposed at the dental treatment site; A power supply unit, which supplies a high-frequency current to the electrodes by means of a constant current drive; a root canal length measuring unit for electrically measuring the position of the tip of the electrode in the root canal; and a control unit that automatically controls the current value of the high-frequency current that energizes the electrode on the power supply unit based on information on the position of the tip of the electrode measured by the root canal length measuring unit, The control unit has: In a first control mode, the root canal length measuring unit is controlled to electrically measure the position of the tip of the electrode in the root canal by supplying a measurement signal to the electrode; as well as In the second control mode, the power supply unit is controlled to supply a high-frequency current to the electrode.

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