WO1998012983A1 - Method and apparatus for apical detection with complex impedance measurement - Google Patents
Method and apparatus for apical detection with complex impedance measurement Download PDFInfo
- Publication number
- WO1998012983A1 WO1998012983A1 PCT/US1997/016425 US9716425W WO9812983A1 WO 1998012983 A1 WO1998012983 A1 WO 1998012983A1 US 9716425 W US9716425 W US 9716425W WO 9812983 A1 WO9812983 A1 WO 9812983A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- die
- probe
- signal
- impedance
- location
- Prior art date
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/05—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves
- A61B5/053—Measuring electrical impedance or conductance of a portion of the body
- A61B5/0534—Measuring electrical impedance or conductance of a portion of the body for testing vitality of teeth
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C19/00—Dental auxiliary appliances
- A61C19/04—Measuring instruments specially adapted for dentistry
- A61C19/041—Measuring instruments specially adapted for dentistry for measuring the length of the root canal of a tooth
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/72—Signal processing specially adapted for physiological signals or for diagnostic purposes
- A61B5/7235—Details of waveform analysis
- A61B5/7253—Details of waveform analysis characterised by using transforms
- A61B5/7257—Details of waveform analysis characterised by using transforms using Fourier transforms
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C19/00—Dental auxiliary appliances
- A61C19/04—Measuring instruments specially adapted for dentistry
- A61C19/042—Measuring instruments specially adapted for dentistry for determining the position of a root apex
Definitions
- the present invention relates to dental equipment, and more particularly, to measuring equipment for dental endodontics.
- the root canal which is a passageway through a tooth, is cleaned of undesired material, such as tissue and fluid.
- a dental tool such as a drill or file, is inserted into the canal and manipulated to remove the undesired material. Then, a flexible filler substance is placed in the root canal and the canal is sealed with a rigid material.
- the narrow root canal does not provide a clear viewing path and medical fluids can partially fill the canal, obscuring vision.
- a particularly troublesome area is at the apex of the root canal, or apical foramen, where the root canal ends and the patient's tissue begins. If the canal is not completely cleaned, debris left inside the canal can prevent proper healing. Therefore, the dental tool should be inserted to the apex of the root canal during cleaning to remove all debris. However, if the dental tool is inserted too deeply, the tool penetrates the tissue, causing swelling and unnecessary trauma for the patient. It is therefore beneficial to identify the apical position of the root canal so that the root canal can be cleaned fully, without excessive trauma to the patient.
- a metal file is inserted into the canal and the tooth is x-rayed.
- the metal file contrasts with the surrounding tooth and body tissue so that the file position can be compared to the apical position.
- This method can be very unreliable, costly, and time-consuming.
- an x-ray will not provide a proper image.
- U.S. Patent No. 5,211,556 to Kobayashi et al. describes an electronic approach to dete ⁇ nining the apical position where a conductive probe is inserted into the root canal and an electrode is positioned in contact with the patient's body, in or near the mouth.
- the probe is moved through the root canal toward the base of the tooth.
- the magnitude of d e impedance, or a component thereof is monitored.
- the magnitude of the impedance begins to change at a different rate.
- the detector determines that the probe is at the apex of the root canal when the impedance is within a designated range.
- the impedance may be affected significantly by the presence of medical liquids or other material in and around the root canal.
- the medical liquids can be conductive, thereby reducing the impedance between the electrodes, as compared to a dry root canal. Consequently, the above-described system is subject to errors in measurement of the apical position. Further, this approach typically requires calibration of the detector during each measurement procedure due to the variations in the amount of medical fluids and other materials in the mouth.
- An apex finder or apical position detector determines apical position by detecting a phase angle, reactive component or spectral response of an impedance between a pair of electrodes.
- a conductive probe inserted into a root canal forms the first electrode.
- the second electrode contacts the patient's body, typically in the mouth area.
- the apical detector uses a sum of a plurality of phase angles where the phase angles are determined at separate frequencies. The phase angles change significantly when the probe contacts the patient's body tissue. By using a combination of measurements at a plurality of frequencies, the apical position detector provides a more accurate indication of the apical position.
- the apical detector also uses a combination of the amplitudes of the impedances in addition to the summation of the phase angles, to improve the accuracy of the apical detector.
- the phase angles and magnitudes are combined mathematically to form a first test score.
- the position detector indicates that the probe is at the apex of the root canal.
- the apical detector averages the magnitudes of the impedances at the testing frequencies to indicate whether the conductivity of d e root canal is too high.
- the apical position detector also produces a second test score based upon the magnitudes to indicate to a user unfavorable measurement conditions in the root canal.
- a display panel presents both test scores with bar graphs to provide an easily recognizable visual indication of the apical position. Additionally, the display panel includes a warning light to provide a prominent indication of unfavorable measurement conditions. To provide even further information, a chime or other acoustic indicator sounds to indicate that the probe has reached the apex of the root canal.
- the apical position detector includes a microprocessor-based controller. The controller uses a Fast-Fourier Transform ("FFT") approach to determine the components of the impedance. The controller develops the test score based upon a sum of phase angles to indicate the position of the probe relative to the apex of the root canal.
- FFT Fast-Fourier Transform
- the electrodes are driven with a pulsed signal.
- the controller compares a spectral response or pulse time delay to a reference standard to identify the apical position.
- Figure 1 is a diagrammatic representation of an apical position detector according to the invention with a probe positioned in a root canal.
- Figure 2 is a partial circuit model and partial block diagram of the apical position detector and root canal of Figure 1.
- Figure 3 A is a firmware flow chart showing the steps for detecting apical position and the signal display and control paths of the position detector of Figure 1.
- Figure 3B is a flowchart of an interrupt handler routine showing steps for user input to the detector of Figure 1.
- Figure 4 is a front elevational view of the display of Figure 1, showing a broad bar graph, a narrow bar graph and a warning light.
- an apical position detector 40 includes a control circuit 42, a display 44, a conductive canal probe 46, a lip electrode 48 and an input interface 49.
- a microprocessor-based controller 50 within the control circuit 42 controls operation of the position detector 40 in response to a software program stored in a nonvolatile program memory 55 as will be described below.
- the input interface 49 includes a switch panel, keyboard, or similar device that allows a user to activate the position detector 40, select options, adjust sensitivity and otherwise control the position detector 40.
- the controller 50 also includes a programmable gate array 53 that acts as an interface between the microprocessor 51 and the remainder of the control circuit 42.
- the programmable gate array 53 also includes a latching circuit that latches commands from the switch panel, keyboard or other device for use in an interrupt handler routine described below with respect to Figure 3B.
- a nonvolatile programmable read-only memory 57 in the controller 50 contains a table of predetermined voltage levels that are accessed by the microprocessor 51 at selected time intervals to produce a digital multi-frequency testing signal V(f,) that provides the principal testing signal for the control circuit 42.
- the testing signal V(f,) has components at five frequencies fi-fj.
- the frequencies are preferably in the range of 200 Hz to 10 kHz, although frequencies exceeding 50 kHz may be within the scope of the invention.
- the frequencies fj-fj are 500 Hz, 1 kHz, 2 kHz, 4 kHz, and 8 kHz, respectively.
- Each of the frequencies f 2 -f5 is double that of the next lower frequency f ⁇ -f_ ⁇ to simplify a Fast-Fourier Transform computation described below.
- the testing signal V(f,) from the controller 50 drives a digital-to- analog (D/A) converter 52.
- the D/A converter 52 produces an analog testing signal V A (f,).
- the test resistor 56 has a resistance on the order of 200 l ⁇ that makes the series combination of the buffer amplifier 54 and test resistor 56 act substantially as a current source 59, such that the probe current Ip(f,) is substantially constant.
- the probe current Ip(fj) is coupled from the test resistor 56 to the probe 46 through a cable 58 that is sufficiently long and flexible to allow easy manipulation of the probe 46.
- the probe current Ip(fj) travels from the cable 58 through the conductive shaft of the probe 46 into a root canal 60 of a tooth 62.
- the current Ip(fi) travels from the distal end of the probe 46 through an end region 64 of the root canal 60 and into a patient's body tissue 66 to the grounded Up electrode 48 to ground.
- the length of the end region 64 will depend upon the depth to which the probe 46 is inserted into the root canal 60.
- the end region 64 and the body tissue 66 form a conductive path having an impedance Z between the probe 46 and the lip electrode 48.
- the impedance Z can be modeled adequately as a parallel combination of a resistor and a capacitor as shown in the equivalent circuit of Figure 2.
- the probe current I p (f,) flows through the impedance Z and produces a node voltage V p (f,) that equals the current I p (f,) times the impedance Z.
- the node voltage V p ⁇ ) will then vary according to the impedance Z, because the current I p fi) is substantially constant.
- the impedance Z is high and has a large resistive component.
- the node voltage V p (f,) is large and has little or no phase shift relative to the current ⁇ p (f,).
- the impedance Z falls and becomes more capacitive. Consequently, the node voltage V p (f,) falls and has an increasing phase shift with respect to the current
- the controller 50 resolves the phase angles 0 ⁇ -0 5 and amplitudes A 1 -A 5 of the various components of the node voltage V p (f,) through a Fast-Fourier Transform technique, as represented by an FFT block 80 in Figure 2.
- the controller 50 then scales the components A 1-A5, 0.-0 5 as represented by a scale block 82 to produce a set of normalized components. From the normalized phase angles 0 ⁇ -0 5 and amplitudes A 1 -A5 the controller 50 produces test scores TEST 1 and TEST2 as represented by the score blocks 84, 86. Based upon die test scores TEST 1, TEST2, the controller 50 provides information to a user through the display 44.
- position detection begins in step 300 with generation of the probe current I p (f,) with five frequency components.
- the probe current I p (f,) is then applied by insertion of the probe 46 in step 301.
- the control circuit 42 monitors the node voltage V P (f,) through a buffer amplifier 68 and an analog-to-digital (A D) converter 70 ( Figure 1).
- the A/D converter 70 provides to the controller 50 a digital signal representing the node voltage V P (f,).
- step 303 the controller 50 evaluates the node voltage V p (f,) to detect a node voltage V p (f,) above at maximum level. If the node voltage V p (f,) is excessive, the controller 50 dete ⁇ riines that the probe 46 is not in or near contact with the patient and the warning light 76 is then activated to provide a substantially instantaneous indication of a non-measuring situation. The controller 50 also freezes the display 44 to hold the last detected measurement.
- step 304 software within the controller 50 performs a
- FFT Fast-Fourier Transform
- AMP 1 will be referred to herein as the amplitude component of the first test score TEST 1 and PHI will be referred to as the phase component of the first test score TEST 1. Also in step 310, the software determines a second test score
- TEST2 5,000/(A ⁇ + A 2 + A3 + A 4 + A 5 )
- the amplitude component AMP ! of the first test score TEST1 varies much less rapidly than the magnitudes A 1 -A 5 , because each of the components is normalized to the first component Ai. Consequently, changes in the magnitudes A 2 -A 5 of the node voltage V p (f,) will be offset by changes in the magnitude Ai for the first frequency.
- the amplitude component AMP 1 will thus vary only to the extent that the rates of change of the amplitudes Ai, A 2 -A 5 differ.
- the phase component PHI of me first test score TEST 1 is largely a function of the relative magnitudes of the reactive and resistive components of the impedance Z.
- the phase component of the first test score TEST 1 will be substantially zero.
- the phase component of the first test score TEST1 will be at its maximum.
- the impedance Z changes from being substantially resistive to substantially reactive as the probe 46 nears contact with the body tissue 66. Therefore, the phase component PHI of the first test score TESTl will change from substantially zero to its maximum magnitude as the probe 46 approaches contact with the body tissue 66.
- the second test score TEST2 will rise quickly as the probe 46 reaches the body tissue 66, because the second test score TEST2 is inversely proportional to the amplitudes A 1 -A 5 and die amplitudes A 1 -A 5 drop as the probe 46 reaches the apical position.
- the second test score TEST2 can therefore be used to confirm the results of the first test score TESTl .
- the second test score TEST2 can indicate whether the magnitude of the impedance Z is within an acceptable range. An excessively low impedance magnitude can indicate unfavorable measurement conditions, such as mav result from excessive medical fluids around the probe 46.
- step 3 1 1 polls to see if the programmable gate array 53 has latched any commands from the input interface 49. If no commands have been latched, the software compares the first or second test scores, TESTl, TEST2 to an acceptable range to identify either contact with the body tissue or unfavorable measurement conditions. A warning light 76 alarm or other indicator is activated in step 314 if the test scores TESTl, TEST2 are outside of the acceptable range.
- the first test score TEST 1 is displayed (step 317) on the display 44 as a broad bar graph 71, as shown in Figure 4.
- the broad bar graph 71 provides a prominent graphical indication of when die distal end of the probe 46 contacts the tissue 66.
- the second test score TEST2 is also provided on the display as a narrow bar graph 72 to indicate whether the impedance Z is within a range that provides adequate results.
- the first and second test scores TEST l, TEST2 can be presented numerically by a seven-segment display or any other suitable indicating device. If, in step 311, a user has input a command through the input interface 49, the software jumps to an interrupt handler routine as shown in Figure 3B.
- step 320 the software accepts latched inputs from the input interface 49 ( Figures 1 and 2) to adjust the display contrast (step 322), select alarm mode (step 324), adjust sensitivity of apex bias level (step 326), or place the controller 50 in a le__rning mode (step 328).
- step 328 the software returns to step 312 to evaluate alarm conditions and display the results.
- the embodiment of Figure 1 utilizes a test signal V(f,) having five principal frequency components, although fewer or more frequency components can be used.
- the test signal V p (f,) can be a short pulse, thereby providing an input having a broad spectral content. Then, the overall spectral content of the node voltage V p (f,) can be monitored and compared to a reference spectral response to determine the apical position.
- the shape of the pulse response at the node can be monitored and compared to a reference pulse response to determine the apical position.
- one or more pulses can be input and the time delay of output pulses can be detected. The time delay can indicate the apical position because die time delay corresponds to die capacitive component of the impedance Z.
- the digital version of die test signal V(f,) can be resolved using a variety of techniques other than the Fast-Fourier Transform technique. For example, a heterodyning circuit or otiier frequency resolving approach can be applied to extract the phases and amplitudes of the various frequency components. Additionally, while the test scores described herein use specific 11
- phase component PHI or another mathematical function of the phases 0j-0 5 can be used to provide a separate indicator of contact between the probe 46 and the tissue 66.
- each of phases 0j-0 5 may be presented separately or a variety of other combinations of the phases and amplitude can be used to provide the indication of contact between the probe 46 and tissue 66.
- the display 44 principally uses a pair of bar graphs to indicate the test scores TESTl, TEST2.
- test scores TESTl, TEST2 may be presented by way of a variety of other display techniques, including numerical indicators, colored lights, or any of a variety of other display techniques.
- the first test score TESTl can be used to activate a chime, beeper, or other audible indication of contact with the tissue 66.
- a chime or other indicator can be used to indicate unacceptable measurement conditions in place of or as a complement to the warning light 76 described above. Accordingly, die invention is not limited except as by die appended claims.
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP51571398A JP2002509455A (en) | 1996-09-25 | 1997-09-15 | Method and apparatus for apical detection by complex impedance measurement |
AU44829/97A AU4482997A (en) | 1996-09-25 | 1997-09-15 | Method and apparatus for apical detection with complex impedance measureme nt |
EP97943334A EP0934030A1 (en) | 1996-09-25 | 1997-09-15 | Method and apparatus for apical detection with complex impedance measurement |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/719,333 US5759159A (en) | 1996-09-25 | 1996-09-25 | Method and apparatus for apical detection with complex impedance measurement |
US08/719,333 | 1996-09-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998012983A1 true WO1998012983A1 (en) | 1998-04-02 |
Family
ID=24889661
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1997/016425 WO1998012983A1 (en) | 1996-09-25 | 1997-09-15 | Method and apparatus for apical detection with complex impedance measurement |
Country Status (5)
Country | Link |
---|---|
US (1) | US5759159A (en) |
EP (1) | EP0934030A1 (en) |
JP (1) | JP2002509455A (en) |
AU (1) | AU4482997A (en) |
WO (1) | WO1998012983A1 (en) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2001047414A1 (en) * | 1999-12-27 | 2001-07-05 | Forum Engineering Technologies (96) Ltd. | Device for detection of a tooth root apex |
WO2003065890A2 (en) * | 2002-02-08 | 2003-08-14 | The University Court Of The University Of Dundee | Test equipment and portable test device |
US6989091B2 (en) | 1998-10-16 | 2006-01-24 | World Energy Systems Corporation | Deep conversion combining the demetallization and the conversion of crudes, residues, or heavy oils into light liquids with pure or impure oxygenated compounds |
GB2385136B (en) * | 2002-02-08 | 2006-05-17 | Univ Dundee | Method and apparatus for applying electrical stimulus to a system and acquiring a system response |
WO2008155751A1 (en) * | 2007-06-21 | 2008-12-24 | Medicn.R.G. Ltd. | Multi-frequency apex locator |
CN102762167A (en) * | 2010-01-14 | 2012-10-31 | 恩登萨菲有限公司 | Apparatus and methods for determining the location of the apex of a dental root canal |
US9149235B2 (en) | 2004-06-18 | 2015-10-06 | Impedimed Limited | Oedema detection |
US9392947B2 (en) | 2008-02-15 | 2016-07-19 | Impedimed Limited | Blood flow assessment of venous insufficiency |
US9585593B2 (en) | 2009-11-18 | 2017-03-07 | Chung Shing Fan | Signal distribution for patient-electrode measurements |
US9615767B2 (en) | 2009-10-26 | 2017-04-11 | Impedimed Limited | Fluid level indicator determination |
US10307074B2 (en) | 2007-04-20 | 2019-06-04 | Impedimed Limited | Monitoring system and probe |
US11660013B2 (en) | 2005-07-01 | 2023-05-30 | Impedimed Limited | Monitoring system |
US11737678B2 (en) | 2005-07-01 | 2023-08-29 | Impedimed Limited | Monitoring system |
Families Citing this family (147)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB9610101D0 (en) * | 1996-05-15 | 1996-07-24 | Univ Dundee | Methods and apparatus for the detection of dental caries |
ATE306213T1 (en) | 1998-12-23 | 2005-10-15 | Nuvasive Inc | DEVICES FOR CANNULATION AND NERVE MONITORING |
CA2363254C (en) | 1999-03-07 | 2009-05-05 | Discure Ltd. | Method and apparatus for computerized surgery |
AUPQ113799A0 (en) * | 1999-06-22 | 1999-07-15 | University Of Queensland, The | A method and device for measuring lymphoedema |
US6235018B1 (en) * | 1999-10-29 | 2001-05-22 | Cryoflex, Inc. | Method and apparatus for monitoring cryosurgical operations |
WO2001037728A1 (en) | 1999-11-24 | 2001-05-31 | Nuvasive, Inc. | Electromyography system |
US6466817B1 (en) * | 1999-11-24 | 2002-10-15 | Nuvasive, Inc. | Nerve proximity and status detection system and method |
US6760616B2 (en) * | 2000-05-18 | 2004-07-06 | Nu Vasive, Inc. | Tissue discrimination and applications in medical procedures |
US7713063B2 (en) * | 2001-05-03 | 2010-05-11 | Lee Charles Q | Dental training device |
US6988894B2 (en) * | 2001-05-03 | 2006-01-24 | Lee Charles Q | Dental training device |
JP4295086B2 (en) | 2001-07-11 | 2009-07-15 | ヌバシブ, インコーポレイテッド | System and method for determining nerve proximity, nerve orientation, and pathology during surgery |
JP2005503857A (en) | 2001-09-25 | 2005-02-10 | ヌバシブ, インコーポレイテッド | Systems and methods for performing surgical procedures and surgical diagnosis |
US7664544B2 (en) | 2002-10-30 | 2010-02-16 | Nuvasive, Inc. | System and methods for performing percutaneous pedicle integrity assessments |
US8147421B2 (en) | 2003-01-15 | 2012-04-03 | Nuvasive, Inc. | System and methods for determining nerve direction to a surgical instrument |
US7582058B1 (en) | 2002-06-26 | 2009-09-01 | Nuvasive, Inc. | Surgical access system and related methods |
US6845265B2 (en) | 2002-07-26 | 2005-01-18 | Aseptico, Inc. | Systems and methods for locating a tooth's apical foramen |
US7758342B2 (en) * | 2002-07-26 | 2010-07-20 | Aseptico, Inc. | Detecting and indicating a proximity of a dental instrument to a tooth apical foramen |
US8137284B2 (en) * | 2002-10-08 | 2012-03-20 | Nuvasive, Inc. | Surgical access system and related methods |
AU2002951925A0 (en) * | 2002-10-09 | 2002-10-24 | Queensland University Of Technology | An Impedence Cardiography Device |
JP2006507057A (en) * | 2002-11-22 | 2006-03-02 | インぺディメッド プロプライエタリー リミテッド | Multi-frequency bioimpedance measurement method |
EE04767B1 (en) * | 2002-12-06 | 2007-02-15 | Tallinna Tehnika�likool | Method and apparatus for measuring electrical bio-impedance |
US7691057B2 (en) | 2003-01-16 | 2010-04-06 | Nuvasive, Inc. | Surgical access system and related methods |
US7819801B2 (en) | 2003-02-27 | 2010-10-26 | Nuvasive, Inc. | Surgical access system and related methods |
MXPA05010221A (en) * | 2003-03-25 | 2006-02-22 | Terry O Herndon | Drill device and method for forming microconduits. |
US6968229B2 (en) * | 2003-05-06 | 2005-11-22 | Ormco Corporation | Apex locating system |
US20040225228A1 (en) * | 2003-05-08 | 2004-11-11 | Ferree Bret A. | Neurophysiological apparatus and procedures |
DE112004001035B4 (en) * | 2003-06-11 | 2014-09-11 | Toei Electric Co., Ltd. | Device for determining the position of a tooth root tip |
EP1675508B1 (en) * | 2003-08-05 | 2016-04-20 | NuVasive, Inc. | System for performing dynamic pedicle integrity assessments |
US7905840B2 (en) * | 2003-10-17 | 2011-03-15 | Nuvasive, Inc. | Surgical access system and related methods |
AU2004275877B2 (en) | 2003-09-25 | 2008-09-04 | Nuvasive, Inc. | Surgical access system and related methods |
US8313430B1 (en) | 2006-01-11 | 2012-11-20 | Nuvasive, Inc. | Surgical access system and related methods |
US8068906B2 (en) | 2004-06-21 | 2011-11-29 | Aorora Technologies Pty Ltd | Cardiac monitoring system |
US9622732B2 (en) | 2004-10-08 | 2017-04-18 | Nuvasive, Inc. | Surgical access system and related methods |
AU2005295589B2 (en) | 2004-10-15 | 2009-12-03 | Baxano, Inc. | Devices and methods for tissue removal |
US8062300B2 (en) | 2006-05-04 | 2011-11-22 | Baxano, Inc. | Tissue removal with at least partially flexible devices |
US7738968B2 (en) | 2004-10-15 | 2010-06-15 | Baxano, Inc. | Devices and methods for selective surgical removal of tissue |
US20100331883A1 (en) | 2004-10-15 | 2010-12-30 | Schmitz Gregory P | Access and tissue modification systems and methods |
US20110190772A1 (en) | 2004-10-15 | 2011-08-04 | Vahid Saadat | Powered tissue modification devices and methods |
US9101386B2 (en) | 2004-10-15 | 2015-08-11 | Amendia, Inc. | Devices and methods for treating tissue |
US7578819B2 (en) | 2005-05-16 | 2009-08-25 | Baxano, Inc. | Spinal access and neural localization |
US8617163B2 (en) | 2004-10-15 | 2013-12-31 | Baxano Surgical, Inc. | Methods, systems and devices for carpal tunnel release |
US7887538B2 (en) | 2005-10-15 | 2011-02-15 | Baxano, Inc. | Methods and apparatus for tissue modification |
US8430881B2 (en) | 2004-10-15 | 2013-04-30 | Baxano, Inc. | Mechanical tissue modification devices and methods |
US7738969B2 (en) | 2004-10-15 | 2010-06-15 | Baxano, Inc. | Devices and methods for selective surgical removal of tissue |
US7938830B2 (en) | 2004-10-15 | 2011-05-10 | Baxano, Inc. | Powered tissue modification devices and methods |
US8257356B2 (en) | 2004-10-15 | 2012-09-04 | Baxano, Inc. | Guidewire exchange systems to treat spinal stenosis |
US8048080B2 (en) | 2004-10-15 | 2011-11-01 | Baxano, Inc. | Flexible tissue rasp |
US9247952B2 (en) | 2004-10-15 | 2016-02-02 | Amendia, Inc. | Devices and methods for tissue access |
US8221397B2 (en) | 2004-10-15 | 2012-07-17 | Baxano, Inc. | Devices and methods for tissue modification |
US7959577B2 (en) | 2007-09-06 | 2011-06-14 | Baxano, Inc. | Method, system, and apparatus for neural localization |
WO2006056074A1 (en) | 2004-11-26 | 2006-06-01 | Z-Tech (Canada) Inc. | Weighted gradient method and system for diagnosing disease |
US8109981B2 (en) * | 2005-01-25 | 2012-02-07 | Valam Corporation | Optical therapies and devices |
US7785253B1 (en) | 2005-01-31 | 2010-08-31 | Nuvasive, Inc. | Surgical access system and related methods |
WO2006084194A2 (en) * | 2005-02-02 | 2006-08-10 | Nuvasive, Inc. | System and methods for monitoring during anterior surgery |
IL166949A (en) * | 2005-02-17 | 2010-04-29 | Medic Nrg Ltd | Dental root canal apex measuring apparatus and method |
WO2007002992A1 (en) * | 2005-07-01 | 2007-01-11 | Impedance Cardiology Systems Inc. | Pulmonary monitoring system |
US8740783B2 (en) * | 2005-07-20 | 2014-06-03 | Nuvasive, Inc. | System and methods for performing neurophysiologic assessments with pressure monitoring |
CA2615845A1 (en) * | 2005-07-20 | 2007-01-25 | Impedance Cardiology Systems, Inc. | Index determination |
US8328851B2 (en) | 2005-07-28 | 2012-12-11 | Nuvasive, Inc. | Total disc replacement system and related methods |
US8099250B2 (en) * | 2005-08-02 | 2012-01-17 | Impedimed Limited | Impedance parameter values |
BRPI0504065A (en) * | 2005-09-06 | 2007-05-22 | Ronaldo Piazzalunga | root spectral attenuation coefficient for use in endodontic foraminal locator |
WO2007038290A2 (en) | 2005-09-22 | 2007-04-05 | Nuvasive, Inc. | Multi-channel stimulation threshold detection algorithm for use in neurophysiology monitoring |
US8568317B1 (en) | 2005-09-27 | 2013-10-29 | Nuvasive, Inc. | System and methods for nerve monitoring |
WO2007041783A1 (en) | 2005-10-11 | 2007-04-19 | Impedance Cardiology Systems, Inc. | Hydration status monitoring |
US8092456B2 (en) | 2005-10-15 | 2012-01-10 | Baxano, Inc. | Multiple pathways for spinal nerve root decompression from a single access point |
US20080086034A1 (en) | 2006-08-29 | 2008-04-10 | Baxano, Inc. | Tissue Access Guidewire System and Method |
US8062298B2 (en) | 2005-10-15 | 2011-11-22 | Baxano, Inc. | Flexible tissue removal devices and methods |
US8366712B2 (en) | 2005-10-15 | 2013-02-05 | Baxano, Inc. | Multiple pathways for spinal nerve root decompression from a single access point |
EP1951145A4 (en) * | 2005-11-21 | 2013-12-25 | Ilan Chron | Apical position locator |
US8406866B2 (en) | 2005-12-06 | 2013-03-26 | St. Jude Medical, Atrial Fibrillation Division, Inc. | System and method for assessing coupling between an electrode and tissue |
WO2007067940A2 (en) * | 2005-12-06 | 2007-06-14 | St. Jude Medical, Atrial Fibrillation Division, Inc. | Assessment of electrode coupling for tissue ablation |
US20090177111A1 (en) * | 2006-12-06 | 2009-07-09 | Miller Stephan P | System and method for displaying contact between a catheter and tissue |
WO2007070361A2 (en) * | 2005-12-06 | 2007-06-21 | St. Jude Medical, Atrial Fibrillation Division, Inc. | Assessment of electrode coupling for tissue ablation |
US8603084B2 (en) | 2005-12-06 | 2013-12-10 | St. Jude Medical, Atrial Fibrillation Division, Inc. | System and method for assessing the formation of a lesion in tissue |
US9271782B2 (en) | 2005-12-06 | 2016-03-01 | St. Jude Medical, Atrial Fibrillation Division, Inc. | Assessment of electrode coupling of tissue ablation |
US9492226B2 (en) * | 2005-12-06 | 2016-11-15 | St. Jude Medical, Atrial Fibrillation Division, Inc. | Graphical user interface for real-time RF lesion depth display |
US10362959B2 (en) | 2005-12-06 | 2019-07-30 | St. Jude Medical, Atrial Fibrillation Division, Inc. | System and method for assessing the proximity of an electrode to tissue in a body |
US9254163B2 (en) | 2005-12-06 | 2016-02-09 | St. Jude Medical, Atrial Fibrillation Division, Inc. | Assessment of electrode coupling for tissue ablation |
US8403925B2 (en) | 2006-12-06 | 2013-03-26 | St. Jude Medical, Atrial Fibrillation Division, Inc. | System and method for assessing lesions in tissue |
EP2015698B1 (en) | 2006-04-20 | 2017-11-15 | Sonendo, Inc. | Apparatus for treating root canals of teeth |
US10835355B2 (en) | 2006-04-20 | 2020-11-17 | Sonendo, Inc. | Apparatus and methods for treating root canals of teeth |
WO2007137333A1 (en) * | 2006-05-30 | 2007-12-06 | The University Of Queensland | Impedance measurements |
US7980854B2 (en) | 2006-08-24 | 2011-07-19 | Medical Dental Advanced Technologies Group, L.L.C. | Dental and medical treatments and procedures |
US9504406B2 (en) | 2006-11-30 | 2016-11-29 | Impedimed Limited | Measurement apparatus |
CA2675438A1 (en) * | 2007-01-15 | 2008-07-24 | Impedimed Limited | Monitoring system |
US20080179309A1 (en) * | 2007-01-25 | 2008-07-31 | Markovsky Robert T | Soldering Iron with Direct Current Powered Heating Element |
US20080187880A1 (en) * | 2007-02-05 | 2008-08-07 | Medicn.R.G. Ltd. | Bluetooth system and method for determining and storing a dental root canal depth measurement |
JP4763637B2 (en) * | 2007-03-16 | 2011-08-31 | 株式会社モリタ製作所 | Root canal length measuring device and root canal treatment device |
CA2703361C (en) * | 2007-03-30 | 2016-06-28 | Impedimed Limited | Active guarding for reduction of resistive and capacitive signal loading with adjustable control of compensation level |
EP2142087B1 (en) * | 2007-04-03 | 2016-06-29 | Nuvasive Inc. | Neurophysiologic monitoring system |
US20080312521A1 (en) * | 2007-06-14 | 2008-12-18 | Solomon Edward G | System and method for determining electrode-tissue contact using phase difference |
US8160690B2 (en) * | 2007-06-14 | 2012-04-17 | Hansen Medical, Inc. | System and method for determining electrode-tissue contact based on amplitude modulation of sensed signal |
WO2008157513A1 (en) * | 2007-06-15 | 2008-12-24 | Baxano, Inc. | Devices and methods for measuring the space around a nerve root |
JP5542050B2 (en) * | 2007-08-09 | 2014-07-09 | インぺディメッド リミテッド | Impedance measurement method and apparatus |
WO2009023488A1 (en) * | 2007-08-10 | 2009-02-19 | Consolidated Research, Inc. | Apparatus and method for high-speed determination of bioelectric electrode impedances |
CA2704061C (en) * | 2007-11-05 | 2017-06-20 | Impedimed Limited | Impedance determination |
IL195418A0 (en) * | 2007-11-20 | 2009-08-03 | Levy Jacob | Method and apparatus for effecting dental measurements using a body contacting electrode |
US8192436B2 (en) | 2007-12-07 | 2012-06-05 | Baxano, Inc. | Tissue modification devices |
US8290578B2 (en) | 2007-12-28 | 2012-10-16 | St. Jude Medical, Atrial Fibrillation Division, Inc. | Method and apparatus for complex impedance compensation |
US9204927B2 (en) | 2009-05-13 | 2015-12-08 | St. Jude Medical, Atrial Fibrillation Division, Inc. | System and method for presenting information representative of lesion formation in tissue during an ablation procedure |
US8437938B2 (en) * | 2008-01-15 | 2013-05-07 | GM Global Technology Operations LLC | Axle torque based cruise control |
EP2313001B8 (en) * | 2008-05-12 | 2012-03-28 | Tallinn University Of Technology | Method and device using shortened square wave waveforms in synchronous signal processing |
BRPI0822655A2 (en) | 2008-06-04 | 2015-06-30 | Colgate Palmolive Co | Oral Care Implement and System |
US8409206B2 (en) | 2008-07-01 | 2013-04-02 | Baxano, Inc. | Tissue modification devices and methods |
US8398641B2 (en) | 2008-07-01 | 2013-03-19 | Baxano, Inc. | Tissue modification devices and methods |
US9314253B2 (en) | 2008-07-01 | 2016-04-19 | Amendia, Inc. | Tissue modification devices and methods |
CA2730732A1 (en) | 2008-07-14 | 2010-01-21 | Baxano, Inc. | Tissue modification devices |
WO2010060152A1 (en) | 2008-11-28 | 2010-06-03 | Impedimed Limited | Impedance measurement process |
WO2010075555A2 (en) | 2008-12-26 | 2010-07-01 | Scott Spann | Minimally-invasive retroperitoneal lateral approach for spinal surgery |
WO2010095135A2 (en) | 2009-02-19 | 2010-08-26 | Medicn.R.G. Ltd. | Apex locator mounted on a handpiece |
JP5582619B2 (en) | 2009-03-13 | 2014-09-03 | バクサノ,インク. | Flexible nerve position determination device |
US8287597B1 (en) | 2009-04-16 | 2012-10-16 | Nuvasive, Inc. | Method and apparatus for performing spine surgery |
US9351845B1 (en) | 2009-04-16 | 2016-05-31 | Nuvasive, Inc. | Method and apparatus for performing spine surgery |
US8394102B2 (en) | 2009-06-25 | 2013-03-12 | Baxano, Inc. | Surgical tools for treatment of spinal stenosis |
JP5367530B2 (en) * | 2009-10-22 | 2013-12-11 | 株式会社アドテックス | Apical position detector |
AU2010315040B2 (en) * | 2009-11-06 | 2015-01-22 | The Research Foundation Of State University Of New York | Device and method for the detection of non-cavitated early dental caries lesions |
JP5902096B2 (en) | 2009-11-13 | 2016-04-13 | ソネンド インコーポレイテッド | Liquid jetting apparatus and method for dental treatment |
EP2409664B1 (en) * | 2010-07-22 | 2013-10-30 | W & H Dentalwerk Bürmoos GmbH | Medicinal treatment device and method for regulating same |
US9392953B1 (en) | 2010-09-17 | 2016-07-19 | Nuvasive, Inc. | Neurophysiologic monitoring |
CN107115154B (en) | 2010-10-21 | 2021-06-15 | 索南多股份有限公司 | Apparatus, methods and combinations for endodontic treatment |
US8790406B1 (en) | 2011-04-01 | 2014-07-29 | William D. Smith | Systems and methods for performing spine surgery |
IL214265A0 (en) * | 2011-07-24 | 2011-09-27 | Creative Team Instr Ltd | High precision impedance converter apparatus for endodontic procedures |
AU2012299061B2 (en) | 2011-08-19 | 2017-02-23 | Nuvasive, Inc. | Surgical retractor system and methods of use |
US9198765B1 (en) | 2011-10-31 | 2015-12-01 | Nuvasive, Inc. | Expandable spinal fusion implants and related methods |
JP2015512658A (en) | 2011-12-14 | 2015-04-30 | インターセクション・メディカル・インコーポレイテッドIntersection Medical,Inc. | Device, system and method for determining relative spatial variation of subsurface resistivity to frequency in tissue |
EP2836156B1 (en) | 2012-03-22 | 2024-04-17 | Sonendo, Inc. | Apparatus for cleaning teeth |
US10631962B2 (en) | 2012-04-13 | 2020-04-28 | Sonendo, Inc. | Apparatus and methods for cleaning teeth and gingival pockets |
US11259737B2 (en) | 2012-11-06 | 2022-03-01 | Nuvasive, Inc. | Systems and methods for performing neurophysiologic monitoring during spine surgery |
US11877860B2 (en) | 2012-11-06 | 2024-01-23 | Nuvasive, Inc. | Systems and methods for performing neurophysiologic monitoring during spine surgery |
US9757067B1 (en) | 2012-11-09 | 2017-09-12 | Nuvasive, Inc. | Systems and methods for performing neurophysiologic monitoring during spine surgery |
EP3943042B1 (en) | 2012-12-20 | 2024-03-13 | Sonendo, Inc. | Apparatus for cleaning teeth and root canals |
US10363120B2 (en) | 2012-12-20 | 2019-07-30 | Sonendo, Inc. | Apparatus and methods for cleaning teeth and root canals |
CA2900252C (en) | 2013-02-04 | 2021-11-16 | Sonendo, Inc. | Dental treatment system |
US9757072B1 (en) | 2013-02-11 | 2017-09-12 | Nuvasive, Inc. | Waveform marker placement algorithm for use in neurophysiologic monitoring |
US10098585B2 (en) | 2013-03-15 | 2018-10-16 | Cadwell Laboratories, Inc. | Neuromonitoring systems and methods |
US10722325B2 (en) | 2013-05-01 | 2020-07-28 | Sonendo, Inc. | Apparatus and methods for treating teeth |
EP3013277B1 (en) | 2013-06-26 | 2023-07-19 | Sonendo, Inc. | Apparatus and methods for filling teeth and root canals |
KR101581124B1 (en) * | 2014-06-17 | 2015-12-31 | 비엔엘바이오테크 주식회사 | System and method for measuring length of root canal based on wireless type |
US10420480B1 (en) | 2014-09-16 | 2019-09-24 | Nuvasive, Inc. | Systems and methods for performing neurophysiologic monitoring |
US10687729B2 (en) * | 2014-11-24 | 2020-06-23 | Koninklijke Philips N.V. | Apparatus and method for estimating a value of a physiological characteristic |
US10543060B2 (en) | 2015-12-03 | 2020-01-28 | Ormco Corporation | Fluted endodontic file |
US10806544B2 (en) | 2016-04-04 | 2020-10-20 | Sonendo, Inc. | Systems and methods for removing foreign objects from root canals |
US9935395B1 (en) | 2017-01-23 | 2018-04-03 | Cadwell Laboratories, Inc. | Mass connection plate for electrical connectors |
USD842474S1 (en) | 2017-10-20 | 2019-03-05 | Ormco Corporation | Endodontic file |
US11253182B2 (en) | 2018-05-04 | 2022-02-22 | Cadwell Laboratories, Inc. | Apparatus and method for polyphasic multi-output constant-current and constant-voltage neurophysiological stimulation |
US11443649B2 (en) | 2018-06-29 | 2022-09-13 | Cadwell Laboratories, Inc. | Neurophysiological monitoring training simulator |
USD997355S1 (en) | 2020-10-07 | 2023-08-29 | Sonendo, Inc. | Dental treatment instrument |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3993044A (en) * | 1975-03-10 | 1976-11-23 | Mcguffin William G | Method and device for determining the length of a root canal of a tooth |
US4193408A (en) * | 1976-03-05 | 1980-03-18 | Shirota Electric Furnace Material Co., Ltd. | Endodontic therapy instrument |
US5080586A (en) * | 1990-09-24 | 1992-01-14 | Osada Research Institute, Ltd. | Apical foramen position detector for use in dental treatment |
US5096419A (en) * | 1991-08-14 | 1992-03-17 | Kabushiki Kaisha Morita Seisakusho | Apparatus and method for detecting an apical position |
US5280429A (en) * | 1991-04-30 | 1994-01-18 | Xitron Technologies | Method and apparatus for displaying multi-frequency bio-impedance |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
HU178505B (en) * | 1979-05-14 | 1982-05-28 | Tibor Dery | Device for determining and digital signalling the position of root treating instruments in the root duct |
US3901216A (en) * | 1973-12-20 | 1975-08-26 | Milton R Felger | Method for measuring endodontic working lengths |
US4447206A (en) * | 1982-01-18 | 1984-05-08 | Junji Ushiyama | Device and method for detecting apical constriction in root canal of tooth |
US4526179A (en) * | 1983-01-28 | 1985-07-02 | Leonard Salesky | Digital apical foramen locating apparatus |
US5020541A (en) * | 1988-07-13 | 1991-06-04 | Physio-Control Corporation | Apparatus for sensing lead and transthoracic impedances |
JPH02271854A (en) * | 1989-04-14 | 1990-11-06 | Takeshi Saito | Dental root canal treating device |
JPH0432708U (en) * | 1990-07-13 | 1992-03-17 | ||
US5063937A (en) * | 1990-09-12 | 1991-11-12 | Wright State University | Multiple frequency bio-impedance measurement system |
JP3113095B2 (en) * | 1991-09-30 | 2000-11-27 | 株式会社モリタ製作所 | Dental root canal examination device |
US5211556A (en) * | 1991-11-27 | 1993-05-18 | Kabushiki Kaisha Morita Seisakusho | Root canal meter |
-
1996
- 1996-09-25 US US08/719,333 patent/US5759159A/en not_active Expired - Fee Related
-
1997
- 1997-09-15 JP JP51571398A patent/JP2002509455A/en active Pending
- 1997-09-15 AU AU44829/97A patent/AU4482997A/en not_active Abandoned
- 1997-09-15 WO PCT/US1997/016425 patent/WO1998012983A1/en not_active Application Discontinuation
- 1997-09-15 EP EP97943334A patent/EP0934030A1/en not_active Withdrawn
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3993044A (en) * | 1975-03-10 | 1976-11-23 | Mcguffin William G | Method and device for determining the length of a root canal of a tooth |
US4193408A (en) * | 1976-03-05 | 1980-03-18 | Shirota Electric Furnace Material Co., Ltd. | Endodontic therapy instrument |
US5080586A (en) * | 1990-09-24 | 1992-01-14 | Osada Research Institute, Ltd. | Apical foramen position detector for use in dental treatment |
US5280429A (en) * | 1991-04-30 | 1994-01-18 | Xitron Technologies | Method and apparatus for displaying multi-frequency bio-impedance |
US5096419A (en) * | 1991-08-14 | 1992-03-17 | Kabushiki Kaisha Morita Seisakusho | Apparatus and method for detecting an apical position |
Cited By (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6989091B2 (en) | 1998-10-16 | 2006-01-24 | World Energy Systems Corporation | Deep conversion combining the demetallization and the conversion of crudes, residues, or heavy oils into light liquids with pure or impure oxygenated compounds |
US7967954B2 (en) | 1998-10-16 | 2011-06-28 | World Energy Systems Corporation | Deep conversion combining the demetallization and the conversion of crudes, residues or heavy oils into light liquids with pure or impure oxygenated compounds |
US6425875B1 (en) | 1999-12-27 | 2002-07-30 | Forum Engineering Technologies (96) Ltd. | Method and device for detection of a tooth root apex |
WO2001047414A1 (en) * | 1999-12-27 | 2001-07-05 | Forum Engineering Technologies (96) Ltd. | Device for detection of a tooth root apex |
US8359179B2 (en) | 2002-02-08 | 2013-01-22 | 3D Diagnostic Imaging Plc | Test equipment and portable test device |
GB2385136B (en) * | 2002-02-08 | 2006-05-17 | Univ Dundee | Method and apparatus for applying electrical stimulus to a system and acquiring a system response |
WO2003065890A3 (en) * | 2002-02-08 | 2004-05-06 | Univ Dundee | Test equipment and portable test device |
WO2003065890A2 (en) * | 2002-02-08 | 2003-08-14 | The University Court Of The University Of Dundee | Test equipment and portable test device |
US9149235B2 (en) | 2004-06-18 | 2015-10-06 | Impedimed Limited | Oedema detection |
US11737678B2 (en) | 2005-07-01 | 2023-08-29 | Impedimed Limited | Monitoring system |
US11660013B2 (en) | 2005-07-01 | 2023-05-30 | Impedimed Limited | Monitoring system |
US10307074B2 (en) | 2007-04-20 | 2019-06-04 | Impedimed Limited | Monitoring system and probe |
WO2008155751A1 (en) * | 2007-06-21 | 2008-12-24 | Medicn.R.G. Ltd. | Multi-frequency apex locator |
US9392947B2 (en) | 2008-02-15 | 2016-07-19 | Impedimed Limited | Blood flow assessment of venous insufficiency |
US9615767B2 (en) | 2009-10-26 | 2017-04-11 | Impedimed Limited | Fluid level indicator determination |
US9585593B2 (en) | 2009-11-18 | 2017-03-07 | Chung Shing Fan | Signal distribution for patient-electrode measurements |
CN102762167A (en) * | 2010-01-14 | 2012-10-31 | 恩登萨菲有限公司 | Apparatus and methods for determining the location of the apex of a dental root canal |
Also Published As
Publication number | Publication date |
---|---|
US5759159A (en) | 1998-06-02 |
AU4482997A (en) | 1998-04-17 |
JP2002509455A (en) | 2002-03-26 |
EP0934030A1 (en) | 1999-08-11 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5759159A (en) | Method and apparatus for apical detection with complex impedance measurement | |
US6221031B1 (en) | Method and improved device for measuring and locating a tooth apex | |
US6304776B1 (en) | Process and apparatus for the detection of catheter-tissue contact, and also of interactions with the tissue catheter ablation | |
US9198601B2 (en) | Contact sensor and sheath exit sensor | |
US6845265B2 (en) | Systems and methods for locating a tooth's apical foramen | |
EP1720484B1 (en) | Detecting and indicating a proximity of a dental instrument to a tooth apical foramen | |
US6425875B1 (en) | Method and device for detection of a tooth root apex | |
US6059569A (en) | Apical position detection apparatus | |
US20080182223A1 (en) | Dental diagnostic device root canal treating apparatus using the same display unit for root canal treating apparatus and dental diagnostic/treating table | |
EP0663182A1 (en) | Ultrasonic measurement system for the determination of bone density and structure | |
US5096419A (en) | Apparatus and method for detecting an apical position | |
US4193408A (en) | Endodontic therapy instrument | |
US20080280261A1 (en) | Root apex position detection method | |
JP5917403B2 (en) | Device for detecting carious lesions in early teeth without cavity | |
US5049069A (en) | Digital apical foramen locating apparatus with linear graphic display | |
US20090142726A1 (en) | Radicular Spectral Attenuation Coefficient for Use in Endodontic Foraminal Locator | |
JP2006511249A5 (en) | ||
JP5058713B2 (en) | Side branch detection device for detecting side branches extending from the root canal to the periodontal ligament cavity | |
GB2356051A (en) | Measuring the vascularity within bone tissue using electrical contact impedance measurements | |
JP3071245B2 (en) | Root canal length measuring instrument | |
WO2006021891A1 (en) | Apical constriction locator | |
JP2873722B2 (en) | Apical position detection device | |
JP4916871B2 (en) | Ophthalmic ultrasound system | |
JPH0795969A (en) | Device for measuring depth of recessed part of living body and depth measuring probe and calibrating adaptor therefor | |
JPH06181937A (en) | Measuring instrument for root canal length |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE GH HU ID IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT UA UG UZ VN YU ZW AM AZ BY KG KZ MD RU TJ TM |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GH KE LS MW SD SZ UG ZW AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL |
|
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: PA/a/1999/002780 Country of ref document: MX |
|
ENP | Entry into the national phase |
Ref country code: JP Ref document number: 1998 515713 Kind code of ref document: A Format of ref document f/p: F |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1997943334 Country of ref document: EP |
|
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8642 |
|
WWP | Wipo information: published in national office |
Ref document number: 1997943334 Country of ref document: EP |
|
NENP | Non-entry into the national phase |
Ref country code: CA |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 1997943334 Country of ref document: EP |