Dental treatment system for locating a tooth apex - Patent application

Abstract

The present invention relates to a dental treatment system (13) for locating the apex of a patient's tooth, the system comprising a lip clip (2) having a first electrode (3) attachable to the patient's lips, and an electric handheld dental device (21) having a housing (22) having a rotating hub (23) for receiving an endodontic file (4) to be inserted into a root canal of the patient's tooth, a second electrode (6) connected to the rotating hub (23), and a housing (24) adapted to emit visible light (25) and positioned to project the light onto a distal end of the endodontic file (4). an electric measuring unit (8) connectable to both the lip clip (2) and the electric handheld dental device (21) and further adapted to locate the apex of the tooth based on measuring the electrical impedance between the first electrode (3) and the second electrode (6); and a light output unit (10) adapted to output a signal indicative of the located apex, wherein the signal changes the illumination state of the illumination means (24) depending on the distance of the endodontic file (4) to the apex.

Description

[Technical field]

[0001] The present invention relates to a system for locating the apex of a patient's tooth for the purposes of root canal treatment. [Background technology]

[0002] Root canal treatment, also known as endodontic treatment, involves removing infected dental pulp such as nerves, blood vessels, and other cellular tissues from a tooth. FIG. 1 shows a prior art endodontic file (4`) that may be used manually to remove infected dental pulp, particularly from the root canal of a tooth. Root canals generally vary in length. Therefore, the position of the endodontic file (4`) relative to the tooth apex must be accurately determined. Teeth have an electrical impedance, which may be measured with an electronic measuring device commonly known as an apex locator. FIG. 1 shows a prior art apex locator (1`). The apex locator (1`) is usually provided as a tabletop device. The use of the apex locator (1`) during endodontic treatment requires a closed electrical circuit that may be established through a couple of electrodes. As shown in the prior art system of FIG. 1, a first electrode (3`) is provided as a lip clip (2`) that can be attached to the patient's lips. A second electrode (6') is also provided as an endodontic file clip (5') that can be attached to an endodontic file (4') that is to be manually advanced into the root canal of the tooth. The electrical impedance between the labial clip (2') and the endodontic file clip (5') changes with increasing penetration of the endodontic file inside the root canal located between the root canal entrance and the apical constriction. The endodontic file clip (5') as well as the labial clip (2') are typically provided as separate devices that can be connected to the apex locator (1') through a cable (7') with a suitable connector (not shown). As shown diagrammatically in FIG. 2, the apex locator (1') typically comprises an electrical measurement unit (8') and an acoustic / optical output unit (9', 10'). The electrical measurement unit (8') is connectable to the lip clip (2') and the endodontic file clip (5') and is adapted to locate the apex of the tooth based on measuring the electrical impedance between the first electrode (3') and the second electrode (6'). The dashed lines in Fig. 2 illustrate a closed electrical circuit established through the patient's lips and the root canal. The acoustic output unit (9') and the optical output unit (10') are each adapted to output a signal indicative of the location of the apex.As shown in Figures 1 and 2, the audio output unit (9') and the optical output unit (10') typically include a loudspeaker (11') and a display (12') with one or more LEDs, respectively. In prior art applications, the level of distance to the apex is represented through a visible distance indication on the display (12') or through a varying audible tone through the loudspeaker (11').

[0003] It is also commonly known to integrate a prior art apex locator into a dental treatment system. Figure 3 shows a prior art dental treatment system (13') with an integrated apex locator and connector means (14') for connecting a lip clip and an endodontic file clip. This prior art dental treatment system (13') has an optical output unit whose display (12') is realized through a graphical user interface (16') on a dentist's tray (15') and additionally an audio output unit with a loudspeaker.

[0004] A problem with the prior art as shown in Figures 1-3 is that most patients feel stressed when they hear a rising acoustic signal as the dentist advances the endodontic file towards the apex. Moreover, this acoustic signal disturbs the dentist during work. The stressed patient usually asks the dentist to turn off the acoustic signal. In such a situation, the dentist has to use the light output unit alone and thus starts to see the light intermittently either on the display (12`) of the tabletop device in Figure 1 or on the display (12`) on the dentist's tray (15`) in Figure 3. In both scenarios, the dentist has to turn his / her face to monitor the change in the lighting condition on the respective display (12`). However, by turning away from the patient's root canal towards the respective display (12`), the dentist is likely to move / align the endodontic file (4`) in the wrong position / direction in the root canal. However, this unfavorable situation interferes with the endodontic treatment. Summary of the Invention

[0005] It is an object of the present invention to overcome the drawbacks of the prior art and to provide a dental treatment system that allows the dentist to locate the apex of a tooth in a safer and easier manner.

[0006] These objects are achieved through a dental treatment system as defined in claim 1. The subject matter of the dependent claims relates to further developments and embodiments.

[0007] The dental treatment system of the present invention may be used to locate the apex of a patient's tooth. The dental treatment system comprises: a lip clip with a first electrode attachable to the patient's lips; a motorized handheld dental device having a housing, the housing including a rotating hub for receiving an endodontic file to be inserted into the root canal of the patient's tooth, a second electrode connected to the rotating hub, and a lighting means adapted to emit visible light and fitted in the housing (22) in a position such that it can illuminate the distal end of the endodontic file (4); an electrical measurement unit connectable to both the lip clip and the motorized handheld dental device and adapted to locate the apex of the tooth based on measuring the electrical impedance between the first and second electrodes; and a light output unit adapted to output a signal indicative of the location of the apex, where the signal changes the illumination state of said lighting means of the instrument depending on the distance of the endodontic file to the apex.

[0008] The main advantageous effect of the present invention is that, in contrast to the prior art, the dentist does not have to take his eyes off the surgical field, i.e. the root canal, but can learn about the location of the apex by only monitoring the lighting state of the lighting means of the electric handheld dental device used for the endodontic treatment. Another main advantageous effect of the present invention is that the dentist can completely dispense with the use of acoustic signals, and thus can work without being disturbed by such acoustic signals, so that the patient is also relieved from the stress caused by audible sounds.

[0009] According to the present invention, the lighting state may include at least one of the following: on / off state of the lighting means, intensity of the visible light emitted by the lighting means, and color of the visible light emitted by the lighting means. Thus, the distance to the apex may be represented by adjusting the lighting state of the lighting means with different light flashing frequencies, light colors, and / or light intensities according to different distance levels of the endodontic file to the apex.

[0010] In one embodiment, the on / off state of the illumination means changes. In this embodiment, the illumination state is initially ON before the endodontic file contacts the tooth, starts turning ON / OFF with a relatively long OFF duration (e.g., 900 ms) when the endodontic file first contacts the tooth, starts turning ON / OFF with a relatively medium OFF duration (e.g., 500 ms) when the endodontic file is closer to the apex, starts turning ON / OFF with a relatively short OFF duration (e.g., 250 ms) when the endodontic file is very close to the apex, and turns OFF all the time when the endodontic file reaches the apex. The above durations are provided as examples, and different ON / OFF cycles can be used to allow the dentist to recognize the gradually decreasing distance to the apex.

[0011] In another embodiment, the intensity of the visible light emitted by the illumination means is varied, in which the illumination state is initially ON at a relatively high intensity before the endodontic file contacts the tooth, gradually begins to weaken as the endodontic file gets closer and closer to the apex, and is always OFF once the endodontic file reaches the apex.

[0012] In another embodiment, the color of the visible light emitted by the lighting means changes. In this embodiment, the lighting state is initially ON with a particular cool color (e.g., blue) before the endodontic file contacts the tooth, starts to gradually change its color from relatively cooler to warmer colors, e.g., green, yellow, orange, and red, as the endodontic file gradually approaches the apex, and is always OFF once the endodontic file reaches the apex.

[0013] In accordance with the present invention, the dental treatment system may have one or more modes for endodontic treatment. The endodontic treatment modes may be selectively activated by the dentist, preferably via a graphical user interface on a dentist tray of the dental treatment system. The graphical user interface preferably includes a touch-sensitive screen for activating and selecting the endodontic treatment modes. Additionally or alternatively, a foot switch of the dental treatment system may be used for the same purpose.

[0014] In one embodiment, the dental treatment system has a first endodontic treatment mode in which the lighting means of the electric handheld dental device are used to indicate the location of the tooth apex through the lighting state. In this embodiment, the lip clip is preferably connected to the dental treatment system through its connector means. In this embodiment, there is no need to use an endodontic file clip, since the electric circuit can be closed through the integrated second electrode of the electric handheld dental device. The first endodontic treatment mode can be activated when the user removes the electric handheld dental device with the endodontic file from the dentist tray. The dentist tray has a sensor for detecting the presence / absence of the electric handheld dental device with the endodontic file. Alternatively, the first endodontic treatment mode can be activated through a graphical user interface or a foot switch. In this embodiment, the user can preferably set the torque to be applied to the endodontic file, the rotation speed of the endodontic file, and the rotation direction of the endodontic file through the graphical user interface and / or the foot switch during the first endodontic treatment mode.

[0015] In another embodiment, the dental treatment system, in addition to the first endodontic treatment mode, optionally also has a second endodontic treatment mode in which the endodontic file can be held directly by the dentist without using a powered handheld dental device, where a loudspeaker or a display of the graphical user interface of the dentist tray is used to monitor the location of the apex, instead of the lighting means of the powered handheld dental device as in the first endodontic treatment mode. The second endodontic treatment mode can optionally be used to locate the apex by hand-holding the endodontic file and inserting it directly into the root canal, as is commonly done in the prior art, without using a powered handheld dental device. In the second endodontic treatment mode, the lip clip is preferably connected to the dental treatment system via its connector means. In the second endodontic treatment mode, the dentist also uses an endodontic file clip that can be attached to the endodontic file. The endodontic file clip can also be connected to the connector means of the dental treatment system. The second endodontic mode may be activated through the graphical user interface and / or the foot switch.

[0016] In one embodiment, the dental treatment system switches from the second endodontic treatment mode to the first endodontic treatment mode when the dentist removes the powered handheld dental instrument with the endodontic files from the dentist tray, or vice versa. In this embodiment, the second endodontic treatment mode may optionally be used as a default mode, for example, when the patient does not perceive the audible acoustic signal as bothersome or when the dentist decides to use a display on the dentist tray graphical user interface.

[0017] In the following description, the invention is explained in more detail by using exemplary embodiments and by making reference to the drawings. [Brief description of the drawings]

[0018] [Figure 1]FIG. 1 is a perspective view of a system having a table-top apex locator for locating the apex of a tooth according to the prior art. [Diagram 2] FIG. 2 is a schematic diagram of a system for locating the apex of a patient's tooth according to the prior art. [Diagram 3] FIG. 3 is a perspective view of a dental treatment system for locating the apex of a patient's tooth according to the prior art. [Figure 4] FIG. 4 is a perspective view of a dental treatment system for locating an apex of a patient's tooth, according to one embodiment of the present invention. [Diagram 5] 5 is a partial perspective close-up view of a dentist's tray of the dental treatment system of FIG. [Figure 6] 6 is a partial perspective exploded view of the powered handheld dental device of the dental treatment system of FIG. [Figure 7] FIG. 7 is another partial perspective close-up view of the powered handheld dental instrument having an endodontic file of the dental treatment system of FIG. [Figure 8] FIG. 8 is a first endodontic treatment dialog on the graphical user interface of the dental treatment system of FIG. [Figure 9] FIG. 9 is a second endodontic treatment dialog on the graphical user interface of the dental treatment system of FIG. [Figure 10] FIG. 10 illustrates endodontic treatment of a patient by using the dental treatment system of FIG. 4 in a first endodontic treatment mode. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The reference numbers shown in the drawings indicate the elements listed below and will be referenced in the subsequent description of the exemplary embodiments: 1. Apex Locator 2. Lip clip 3. First electrode 4. Endodontic files 5. Endodontic File Clips 6. 61. Second electrode 7. Cable 8. Electrical measuring unit 9. Sound output unit 10. Optical output unit 11. Loudspeakers 12. Display (LED) 13. Dental treatment system 14.Connector means 15. Dentist trays 16. User Interface 17. Chair 18. Assistant Tray 19. Foot Switch 20. Water unit 21. Electric handheld dental devices (instruments) 22. Housing 23. Rotating hub 24.Lighting means (LED) 25.Visible light 26. Taskbar 27.Grip section 28. Head section 29. Neck

[0020] FIG. 4 shows a dental treatment system (13) according to an embodiment of the present invention. The dental treatment system (13) comprises a chair (17) for seating a patient, a dentist tray (15) having a number of tabs for holding various instruments to be used by a dentist during dental treatment, an assistant tray (18) having a number of tabs for holding various instruments to be used by an assistant during dental treatment, and a water unit (20) for washing the instruments and discharging wastewater. A control unit (not shown), such as a PC, is preferably provided inside the base of the chair (17) for controlling the overall operation of the dental treatment system (13). The dentist tray (15) has a graphical user interface (16) with a touch-sensitive display (12) for enabling the dentist to selectively operate various functions of the dental treatment system (13). The dental treatment system (13) also has a foot switch (19) for enabling the dentist to operate various functions of the dental treatment system (13). In this specification, in order to avoid lengthy explanation, technical features of the dental treatment system (13) other than those essential for understanding endodontic treatment are omitted, as they are generally known to those skilled in the art.

[0021] <Endodontic treatment> The dental treatment system (13) of Fig. 4 can be used for endodontic treatment, in particular for locating the apex of a patient's tooth. In the following description, the dental treatment system (13) will be explained in more detail with regard to the different endodontic treatment modes available to the dentist and the respective dialogues that appear on the graphical user interface (16).

[0022] <First endodontic treatment mode and first dialogue> FIG. 10 shows a patient undergoing endodontic treatment according to a first endodontic treatment mode, where the dentist uses a lip clip (2) and a motorized handheld dental device (21) (hereinafter also referred to as instrument) with an endodontic file (4). As shown in more detail in FIG. 5, the lip clip (2) of the dental treatment system (13) comprises a first electrode (3) attachable to the patient's lips. The lip clip (2) can be electrically connected to a connector means (14) on the dentist's tray (15). As shown in more detail in FIG. 5, the motorized handheld dental device (21) used in the first endodontic treatment mode can be removed from the dentist's tray (15) to activate the first dialogue shown in FIG. 8. The dentist's tray (15) comprises a sensor for detecting the removal of the instrument. The first dialogue is described in more detail below. As shown in more detail in FIG. 7, the electric handheld dental device (21) has a housing (22) including a rotating hub (23) for receiving / rotating an endodontic file (4) to be inserted into the root canal of a patient's tooth. The hub (23) is also adapted for use with other dental tools for drilling, screwing, drilling, grinding, etc. As shown in FIG. 6, the housing (22) also includes a second electrode (6) in electrical communication with the rotating hub (23). As shown in more detail in FIG. 7, the housing (22) further includes a lighting means (24) near the rotating hub (23) and adapted to emit visible light (25). The lighting means (24) is positioned to project light onto a working area in the oral cavity facing the rotating hub (23). This allows the root canal of the tooth to be illuminated. The lighting means (24) is fitted in the housing (22) in a position to illuminate the endodontic file (4), in particular the distal end of the endodontic file (4). The lighting means (24) comprises one more LED (24). Each LED may be a white LED, a single color LED, or a multicolor LED that may emit white light or light of different colors depending on a drive signal.

[0023] As shown in Figures 7 and 10, the housing (22) has a grip portion (27) that can be held by a practitioner, a head portion (28) that includes the rotation hub (23), and a neck portion (29) disposed between the grip portion (27) and the head portion (28). The grip portion (27) is preferably detachable from the neck portion (28) and may be provided in the form of a coupling device. Alternatively, the grip portion (29) may be provided integrally with the neck portion (28).

[0024] As shown in Figure 7, the lighting means (24) is fitted into the neck portion (29) on the side facing the work area. Alternatively, in an embodiment not shown, the lighting means (24) can be fitted into the head portion 28 on the side facing the work area.

[0025] In an embodiment not shown, the LED may additionally be optically coupled with a fiber optic element (not shown) for diffusing at least a portion of the light emitted by the LED towards the practitioner / user. The fiber optic element may have an arch-like or ring-like shape. The fiber optic element may be disposed around the neck portion. Alternatively or additionally, the fiber optic element may be disposed around the head portion. The fiber optic element may be disposed such that it at least partially illuminates the endodontic file (4).

[0026] As shown in FIG. 4 (see dashed line), the dental treatment system (13) has an integrated apex locator (1) including an electrical measurement unit (8) connectable to the lip clip (2) via a connector means (14) and to a motorized handheld dental device (21) via a second electrode (6). The electrical measurement unit (8) is adapted to locate the apex of the tooth based on measuring the electrical impedance between the first electrode (3) and said second electrode (6). The integrated apex locator (1) further includes a light output unit (10) adapted to output a signal indicative of the located apex. The signal is transmitted to the lighting means (24) through a wiring in the hose of the instrument (21). This signal drives one or more LEDs of the lighting means (24). The wiring also carries a signal for driving the motor of the instrument (21). The signal changes the lighting state of the lighting means (24) of the instrument (21) depending on the distance of the endodontic file (4) to the apex. As shown in Fig. 10, the dentist can easily monitor the lighting state during the endodontic treatment while viewing the root canal. The apex locator (1), in particular the electrical measurement unit (8) and the light output unit (10), are arranged in the dentist's tray (15). Alternatively, these electrical measurement unit (8) and the light output unit (10) can be arranged in the base of the chair (17) or any other part of the dental treatment system (13).

[0027] In the following description, the first dialog that appears on the graphical user interface (16) during the first endodontic mode as shown in FIG. 8 will be described in more detail according to one embodiment. The dentist may activate the endodontic mode by touching the icon of the endodontic file on the task bar (26). When the dentist removes the electric handheld dental device (21) from the dentist tray (15), the first dialog appears on the graphical user interface (16). As shown in the first dialog, the dentist may set various settings through the use of fields F1-F8. Some of these settings will be explained in the following description. By F1, the proximity level (L) of the apical position may be adjusted. For adjustment, the icon indicated by L is set to point to the last light box or any other one of the preceding light boxes to safely prevent the endodontic file (4) from being advanced beyond the apex. F2 allows the dentist to activate the use of the lighting means 24 and / or the loudspeaker 11. F3 allows the dentist to adjust the torque of the instrument motor and therefore the maximum torque of the endodontic file 4. F4 allows the dentist to adjust whether the instrument motor stops rotating, continues rotating or reverses the direction of rotation when the proximity level (L) is reached. F5 allows switching to a second endodontic mode, which will be described later. F6 indicates the intensity setting of the lighting means 24. F7 allows the direction of rotation of the instrument motor to be set and the rotation state of the instrument motor, such as reverse rotation or stop, when the torque set in F3 is reached. F8 allows the rotation speed of the instrument motor and therefore the rotation speed of the endodontic file 4 to be set.

[0028] <Second endodontic treatment mode and second dialogue> FIG. 9 shows a second dialog on the graphical user interface (16) during the second endodontic treatment mode, according to one embodiment. The dentist may activate the endodontic treatment mode by touching the icon of the endodontic file on the task bar (26). If the dentist does not remove the powered handheld dental device (21) from the dentist's tray (15) or touches F4, the second dialog appears on the graphical user interface (16). In the second endodontic treatment mode, the endodontic file (4) is held directly by the dentist without using the powered handheld dental device (21). In the second endodontic treatment mode, the lip clip (2) is connected to the dental treatment system (13) via the connector means (14). And the dentist also uses an endodontic file clip (5) that can be attached to the endodontic file (4). In this embodiment, the dental treatment system (13) has an acoustic output unit (9) with a loudspeaker (11), as shown in FIG. 5. The loudspeaker (11) or the display (12) on the graphical user interface (16) of the dentist's tray (15) can be selectively used to monitor the position of the apex, instead of the lighting means (24) of the instrument (21) as in the first endodontic treatment mode. The endodontic file clip (5) has a second electrode (61). The electrical measurement unit (8) is adapted to locate the apex of the tooth based on the measurement of the electrical impedance between the first electrode (3) and said second electrode (61), as shown in FIG. 6. The dentist can make various settings, as shown in the second dialogue. During the second endodontic treatment mode, the lighting boxes are gradually highlighted from top to bottom on the display (12) as the endodontic file (4) is advanced in the root canal. Thus, the display (12) not only serves to indicate the location of the apex during the second endodontic treatment, but may also be used to set the proximity level (L) at which the apex is allowed to be reached.

[0029] In alternative embodiments (not shown), the illumination means (24) may have a variety of different configurations: the illumination means may be provided at least partially or entirely around the hub (23), or may be provided on the front, back, or sides of the tapered portion of the housing (22).

Claims

1. A dental treatment system (13) for locating an apex of a patient's tooth, the dental treatment system comprising: a lip clip (2) having a first electrode (3) attachable to the patient's lips; an electric handheld dental device (21) having a housing (22), the housing (22) comprising a rotating hub (23) for receiving an endodontic file (4) to be inserted into a root canal of the patient's tooth, a second electrode (6) connected to the rotating hub (23), and lighting means (24) adapted to emit visible light (25) and fitted in the housing (22) in a position such that it can illuminate a distal end of the endodontic file (4); an electrical measurement unit (8) connectable to both the lip clip (2) and the electric handheld dental device (21), and further adapted to locate the apex of the tooth based on measuring the electrical impedance between the first electrode (3) and the second electrode (6); and a light output unit (10) adapted to output a signal indicative of the located apex, the signal causing a lighting state of the lighting means (24) to change depending on the distance of the endodontic file (4) to the apex.

2. 2. The dental care system (13) of claim 1, characterized in that the lighting conditions include at least one of an on / off state of the lighting means (24), an intensity of the visible light (25) emitted by the lighting means (24), and a color of the visible light (25) emitted by the lighting means (24).

3. 3. A dental treatment system (13) as claimed in claim 1 or 2, characterized in that the housing has a grip portion (27), a head portion (28) including the rotation hub (23), and a neck portion (29) between the grip portion (27) and the head portion (28), and the lighting means (24) is fitted in the neck portion (29).

4. Dental care system (13) according to any one of claims 1 to 3, characterised in that the lighting means (24) comprise one or more LEDs.

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