Method and arrangement for cleaning of a canal

Patent metadata

Field	Value
Publication number	US-12496175-B2
Application number	US-202318121672-A
Country	US
Kind code	B2
Filing date	Mar 15, 2023
Priority date	Sep 25, 2017
Publication date	Dec 16, 2025
Grant date	Dec 16, 2025

Abstract

A method and an arrangement for the cleaning of a circumferentially closed canal using a light guide conducting a laser beam, with the entry of the laser beam into the light guide being interrupted when the free end of the light guide is outside of the canal and/or the movement of the light guide within the canal is monitored and if there is no movement or the movement is below a first threshold value then a signal is triggered and/or the laser radiation is turned off or its output is reduced. The turning off of the laser radiation or its reducing is controlled in dependency of at least one signal change and/or a second threshold and/or a signal change relative to the second threshold determined during at least one course of time starting before and including the entry of the light guide into the canal.

First claim

The invention claimed is:

1 . An arrangement for cleaning a circumferentially closed canal comprising:
a laser radiation source arranged within a laser device; a light guide conducting a laser beam; a delivery device; a first line; a controller; and a handpiece detachably connected to the delivery device, via which at least the laser beam and a liquid are fed to the handpiece, the first line guiding the liquid, with its nozzle directed towards the light guide; wherein the nozzle of the first line is arranged such that the liquid is directed towards a last ⅓ of the light guide at an angle with respect to a longitudinal axis of the light guide, wherein the laser beam is directed into a canal via the light guide which is detachably connected with the handpiece, wherein the controller ensured that laser operation is only possible when the light guide is placed inside a canal, wherein at least one fluid container containing cleaning fluid is attached to the laser device, and wherein the at least one fluid container is a pre-pressurized fluid container.

2 . The arrangement of claim 1 , wherein the handpiece is connected to the at least one optional cartridge from which a line emanates, an opening of which extends on a side of the light guide,
wherein the at least one optional cartridge is detachably connected to the handpiece or plugged into the bandpiece, wherein the opening of the at least one optional cartridge is a closable exit opening that is controllable by an electromagnetically-actuatable valve controlled by the controller, the electromagnetically actuatable valve comprises an excitation part with a magnetic coil, a part of a ferromagnetic core in the handpiece, and a ferromagnetic material as a valve opener as part of an exit valve disposed in the at least one optional cartridge.

3 . The arrangement of claim 1 , wherein the at least one optional cartridge is a plurality of optional cartridges, each configured to use with a different cleaning fluid which is pressurized by compressed air.

4 . The arrangement of claim 1 , wherein the light guide has a metallization on an outer surface of the light guide with two regions that are electrically insulated with respect to one another which enmesh in one another in a comb-like manner at least at the tip of the light guide, and wherein the metallization has one or more hydrophobic characteristics over at least an anterior ⅓ of the light guide.

5 . The arrangement of claim 1 , wherein a movement sensor is integrated into the handpiece or the movement sensor and a rotation encoder are integrated into a delivery system reaching into the handpiece for recognition of the handpiece rotation with respect to the delivery system.

6 . The arrangement of claim 1 , wherein the laser is a diode-pumped Er:YAG laser, Er:YSGG laser or CTE laser with, a pulse duration between 5 μs and 1000 μs, or in a range 25 μs to 400 μs, or in the range of 50 μs to 200 μs, and/or a pulse energy between 0.5 mJ and 50 mJ, or between 1 mJ and 10 mJ and/or a mean output between 0.5 W and 10 W, or between 1 W and 3 W, with a pulse repetition rate in the range 50 Hz to 2000 Hz, or in the range of 50 Hz to 800 Hz.

7 . The arrangement of claim 1 , wherein the arrangement is provided with a control device, as well as a housing that encloses the laser, which is connected to a supply device, through which the arrangement can be supplied with water and/or compressed air.

8 . The arrangement of claim 1 , wherein the laser device has no connection to pressurized air and/or water of a dental chair, and
wherein the laser device is a table top device.

9 . The arrangement of claim 1 , wherein water mist is generated emanating from the hand piece via the nozzle which is an airless working nozzle.

10 . The arrangement of claim 1 , wherein the handpiece is built with a central, not sterilizable part containing optics and electronics and an outer removable, sterilizable envelope as housing or shell with additional optical windows to allow the measurement radiation pass through the shell.

11 . The arrangement of claim 1 , wherein optical fibers are added inside the handpiece in front of sensitive sections of at least one time-to-flight sensor to provide additional pathway length, and
wherein the optical fibers have a length of 2-8 cm.

12 . The arrangement of claim 11 , wherein two or more time-to-flight sensors or measuring chips are used in combination with fibers of different length targeting on the same region to create overlapping time bins to improve a distance resolution, and
wherein time delay differences are created with optical fibers as delay lines of 25 ps in case of two chips or 16 ps and 32 ps in case of 3 chips to improve the distance resolution by enabling to interpolate between the different time bins.

13 . The arrangement of claim 1 , wherein the container is partially filled with 10 ml-1 L of fluid, and
wherein the fluid in the container is sterilized water or physiological saline solution optionally containing bactericidal ingredients.

14 . The arrangement of claim 1 , wherein a second container with a sterilization fluid is attached instead of utilizing the at least one fluid container.

15 . The arrangement of claim 14 , the second container is filled with pressurized gas or a fluid that generates 3-8 bar vapor pressure to support the pressurization of the cartridges mounted on the hand piece.

16 . The arrangement according to claim 1 , wherein the light guide comprises, at least at a portion thereof between the delivery device and the handpiece, a material, which conducts laser pulses up to 50 mJ and/or a mean laser output of 5 W in the wavelength range of 2.69 μm to 2.94 μm, as well as in the wavelength range of 400 nm to 1000 nm.

17 . The arrangement according to claim 16 , wherein the diameter of the light-conducting core of the light guide is between 150 μm and 600 μm.

18 . The arrangement according to claim 1 , wherein the light guide comprises, at least at a portion thereof that is introduced into the canal, a material which conducts laser pulses up to 50 mJ and/or a mean laser output of 5 W in the wavelength range of 2.69 μm to 2.94 μm, as in the wavelength range of 400 nm to 1000 nm.

19 . The arrangement according to claim 18 , wherein the diameter of the light-conducting core of the light guide is between 118 μm and 250 μm, wherein the light guide has a protective layer on its outer side, and/or wherein the light guide has an outer diameter between 200 μm and 300 μm and/or a length between 25 mm and 40 mm.

20 . The arrangement of claim 1 , wherein the controller comprises a processor configured to:
record data of one or several detection methods for detecting the entry of the light guide in the canal over a plurality of time intervals corresponding to a plurality of usages of the light guide; store said data to obtain a plurality of time profiles that define at least a normal use and an abnormal use of the device, said normal use comprising entering the canal with a fiber of the light guide, moving the fiber up and down the canal and removing the fiber from the canal, and said abnormal use comprising moving the fiber tip towards an eye, wherein the processor is further configured to, responsive to obtaining said plurality of time profiles, detect an abnormal use based on the plurality of time profiles, and either prohibit switching the laser on or switch the laser off responsive to said laser being already active.

Assignees

• Dentsply Sirona Inc

Inventors

• Ertl Thomas
• Diebolder Rolf

Classifications

• A61L2/18

  Liquid substances · CPC title

• A61L2/08

  Radiation · CPC title

• A61N5/067

  using laser light · CPC title

• A61C5/50

  Implements for filling root canals; Methods or instruments for medication of tooth nerve channels · CPC title

• A61C1/0046

  Dental lasers (surgical lasers A61B18/20; working by laser beam in general B23K26/00; lasers per se H01S3/00) · CPC title