45 results about "Root canal length" patented technology

The present invention provides a root canal length measuring apparatus and a root canal treatment apparatus which can acquire a position of a measurement electrode with high reproducibility in the same root canal. The root canal length measuring apparatus includes a measurement electrode which is inserted into a root canal, an oral electrode which is held in an oral cavity, a measuring section which applies an electric measuring signal between the measurement electrode and the oral electrode and specifies an apex position so as to measure a root canal length, a memory means which stores position data corresponding to a position of the measurement electrode in a root canal acquired by the measuring section, and an operating means which instructs the memory means to store the position data.

A root canal length measurement device configured for detachable support on a neck of a dental handpiece and having a generally cylindrical electrical contact element that, in use, is resiliently biased by a spring toward an endodontic file rotatably mounted in the handpiece so that a flat surface of the contact element maintains a steady electrical connection with a shank portion of the endodontic file proximate its point of attachment to the handpiece.

The invention relates to a calibration device and method for a root canal length measurement instrument. The calibration device comprises a measurement signal generating circuit, an on-off control circuit, an analog electronic switching circuit, a calibration load circuit and an external measurement circuit, wherein the measurement signal generating circuit is used for generating a current measurement signal, detecting the voltage signal of the calibration load circuit and generating a calibrated current measurement signal; the on-off control circuit is used for controlling the analog electronic switching circuit to be connected to the calibration load circuit or the external measurement circuit; the analog electronic switching circuit is used for outputting the current measurement signal to the calibration load circuit or outputting the calibrated current measurement signal to the external measurement circuit; the external measurement circuit is used for outputting the calibrated current measurement signal to an external root canal file and lip hook circuit. Compared with the prior art, the calibration device has the advantages that the measuring circuit is small in size, the price is low, the failure rate is low, the power consumption is low, the control is simple, the internal structure of the root canal length measurement instrument is more compact, the whole size is smaller, the cost is lower, the function is more reliable, and the calibration accuracy is high.

The A root canal treatment apparatus includes: a handpiece configured to hold a cutting tool in a head in a drivable manner; a motor driver and a micromotor configured to drive the cutting tool; a root canal length measurement circuit; and a control portion. The root canal length measurement circuit is configured to electrically detect a position of a tip end of the cutting tool in a root canal, using the cutting tool as a measuring electrode. The control portion is configured to perform drive for reversely rotating the cutting tool by a predetermined set angle (180 degrees) when the position of the tip end of the cutting tool detected by the root canal length measurement circuit reaches a predetermined set position, and then, stopping rotation.

The present invention relates to a tooth root canal length determinator. It includes power supply, signal acquisition circuit, signal processing circuit and display. The described signal acquisition circuit is formed from reference electrode and detection electrode, between the described reference electrode and detection electrode a human body resistance is formed, the signal acquisition circuit is connected with signal processing circuit, the described signal processing circuit has reference resistance, and can be used for judging the difference of human body resistance and reference resistance and calculating the distance between end portion of detection electrode and apical foramen of tooth.

The invention discloses a machine head with the function of measuring the length of the root canal, wherein the signal circuit is specially arranged for sending the measurement signal from the root canal length measuring circuit to the measuring probe mounted on the head located at the top of the machine head , which is placed in the handpiece and is electrically connected to the measuring probe through contacts near the measuring probe. Therefore, there is no need to connect signal circuits externally to the handpiece for measurement. In addition, this structure improves handpiece workability since there are no leads for connection. Moreover, this structure eliminates the trouble of connecting external leads to the head of the handpiece. Furthermore, it is possible to use a cutting tool with a tail and a cutting portion which are insulated from each other.

The invention discloses a handheld integrated root canal therapeutic apparatus which comprises a driving part, a wire and a main machine part, wherein a machine head is arranged at one end of the driving part, one end, far from the driving part, of the machine head is externally connected with a needle file, one end of the wire is connected with the needle file through the main machine part, the other end of the wire is connected with an electric conductor which is used for being connected with the human body, a motor is arranged in the driving part, the motor is used for driving the machine head to move and driving the needle file to rotate to polish and expand a tooth root canal area, a control unit is further arranged in the main machine part, and the control unit is used for controlling the motor to operate and controlling the needle file to be communicated with the wire at the same time; when the electric conductor is connected with the human body and the needle file contacts a root canal in the oral cavity, the wire is connected with the nerve in the oral cavity through the electric conductor and the needle file to form a loop; a collecting unit is further arranged in the driving part; a calculating unit which is used for processing collected current, voltage and resistance values to obtain the root canal length is arranged in the main machine part. When the handheld integrated root canal therapeutic apparatus disclosed by the invention is implemented, root canal expansion and real-time root canal depth measurement can be achieved at the same time in root canal therapy; furthermore, the handheld integrated root canal therapeutic apparatus is convenient to operate.

The invention discloses a root canal locator and a method for measuring the length of a root canal. A digital signal processor sends a double-frequency excitation signal to a digital-to-analog converter so as to convert the double-frequency excitation signal into an analog signal and send the analog signal to a signal amplification circuit; an analog signal is amplified through a signal amplification circuit and is applied to teeth of the oral cavity of a patient through a root canal file serving as a first electrode, the first electrode makes contact with root canals of the teeth of the patient, a second electrode makes contact with lips of the oral cavity of the patient, and therefore the analog signal generates a feedback signal after passing through the root canals of the teeth of thepatient and is collected by the second electrode; feedback signals are fed back to the signal amplification circuit to be amplified and then sent to a digital-analog sampling channel of the digital signal processor to be sampled and converted into digital signals; at the moment, the amplitude phase of the feedback signal is calculated, the impedance of the root canal of the tooth is calculated, the length of the root canal of the patient is calculated according to the fitting relation between the impedance of the root canal and the length, Kalman filtering processing is conducted, and the final root canal length is obtained and displayed on a display screen.

A dental handpiece for root canal treatment comprises an outer sleeve, a connecting device for connecting the handpiece to a control and analyzing unit, a measurement circuit having a power source and to a drive unit, an electrically conducting tool receptacle and an electrically conducting driving device, wherein the tool receptacle and the driving device are mechanically and electrically connected together so that a driving motion generated by the drive unit can be transmitted via the driving device to the tool receptacle and electrical measurement signals can be transmitted between the driving device and the tool receptacle. A first connection is provided for transmitting the driving motion. A second electrically conducting connection, which may comprise sliding contacts, is provided for transmitting the electrical measurement signals. With separate connections, an improved signal transmission and in particular a low loss of measurement signals of the root canal length measurement during the signal transmission are achieved.

The invention discloses a root canal length measuring method and a root canal length measuring instrument. The method is carried out by the root canal length measuring instrument. The method comprisesthe following steps: receiving a preset period PWM signal inputted from the outside; alternately forming a first high frequency signal with a first sub-period and a second low frequency signal with asecond sub-period; performing voltage amplitude reduction processing on the pwm to respectively obtain a second high frequency signal and a second low frequency signal after the voltage amplitude reduction; applying a second high frequency signal and a second low frequency signal to the tip of the root canal length measuring instrument; acquiring the attenuated second high frequency signal and the attenuated second low frequency signal; determining the root canal length based on the attenuated second high frequency signal and the attenuated second low frequency signal. The method and the instrument can skillfully avoid the influence of the deviation of the hardware parameters on the voltage amplitude when the frequency selection circuit is used, and then the influence on the test results.So that the results of root canal length tester produced by the manufacturer can be consistent.

The invention relates to a charging circuit for a root canal length measuring instrument and a charging state feedback and display method. The charging circuit comprises a lithium battery charging module, a charging state detection module, a single chip microcomputer, a display screen, a green LED lamp driving module and a yellow LED lamp driving module. The output end of the lithium battery charging module is connected with the input end of the charging state detection module, the output end of the charging state detection module is connected with the charging state detection end of the single chip microcomputer, the data display end of the single chip microcomputer is connected with the display screen, the green LED control signal end of the single chip microcomputer is connected with the green LED lamp driving module, and the yellow LED control signal end of the single chip microcomputer is connected with the yellow LED lamp driving module. The charging state of a battery is detected through the single chip microcomputer, a corresponding pattern is displayed through the display screen to inform a user of the charging state of the battery visually, charging indicator lamps are controlled by an IO interface of the single chip microcomputer, and it is avoided that a green LED and a yellow LED light together to bring about error indications.

The invention discloses a length measurement model for a root canal of an isolated tooth and a measurement method of the length measurement model. According to the length measurement model and the measurement method, the technical problems that existing length measurement teaching of the root canal of the isolated tooth is low in simulation degree and is disjointed from practical clinic in the prior art are solved. The length measurement model comprises a base model and a tooth model, wherein an isolated tooth embedding slot is formed in the tooth model, and a conducting gel block and a metalring are arranged in the base model; and when a to-be-measured isolated tooth is embedded into the isolated tooth embedding slot, the tip of the to-be-measured isolated tooth is located in the conducting gel block, one end of the metal ring is located in the conducting gel block, the other end of the metal ring is located out of the base model. According to the measurement method, the length of the root canal is measured by virtue of a root measurement instrument, and the root measurement instrument is connected with a root canal file and the metal ring through two leads. The length of the root canal of the isolated tooth mounted in the measurement model on a head-simulated model is measured by virtue of the root measurement instrument, so that a teaching scene is basically accordant withpractical clinic root canal length measurement scene, the simulation level of the teaching is increased, and the teaching is closer to the clinical practice and is more vivid and practical.

A dental treatment apparatus includes a holder, a power supply, root canal length measurement circuitry, and control circuitry. The holder holds an electrode placed in a root canal. The power supply energizes file with a high-frequency current. The root canal length measurement circuitry electrically measures a position of a distal end of electrode in the root canal. The control circuitry causes, in accordance with information on the position of the distal end of the electrode measured by root canal length measurement circuitry, the power supply to control a current value of the high-frequency current which energizes the electrode.