SYSTEM AND METHOD FOR LASER BASED ENDODONTIC TREATMENT

Abstract

The disclosed invention relates to a system and method for treatment of root canals, e.g., to clean, decontaminate and remove the smear layer. The system can include a laser source; a hand piece; and a device for directing radiation emitted by the laser source to a liquid creating pressure that result in irrigation. In some cases, the handpiece can include an optical element adapted to modulate a laser beam such that it is dispersive or focused.

Claims

1. A system for providing a laser treatment to an endodontic canal to decontaminate, clean, and remove a smear layer of the endodontic canal, the system comprising: a handpiece comprising a CO.sub.2 laser source for generating and delivering a plurality of laser pulses of a laser beam having a wavelength in a range from 9 μm to 11 μm; and an optical element to adapt the laser beam such that the plurality of laser pulses are delivered into a treatment site at the endodontic canal, wherein the laser pulses includes a laser irradiation energy level, and wherein the laser irradiation energy level creates a pressure wave and induces agitation or cavitation of irrigants in the root canal.

2. The system of claim 1, wherein the laser treatment provides a rate of irrigation or movement of irrigants from about 1 to about 20 mm/s.

3. The system of claim 1, wherein the laser treatment provides a substantially complete removal of the smear layer.

4. The system of claim 1, wherein the laser irradiation energy level of a laser pulse of the plurality of laser pulses is no more than about 1 J/cm.sup.2.

5. The system of claim 1, wherein a laser pulse of the plurality of laser pulses comprises a duration from about 1 to about 100 μsec.

6. The system of claim 1, further comprising a beam guidance system, wherein the beam guidance system is adapted to direct the plurality of laser pulses to respective tissue locations in a pattern.

7. The system of claim 6, wherein the pattern comprises a number of locations from about 15 locations to about 1500 locations.

8. The system of claim 6, wherein the beam guidance system is adapted to repeat directing the plurality of laser pulses to respective tissue locations in a pattern.

9. The system of claim 6, wherein the pattern comprises at least one tissue location, at least one location non-adjacent to the tissue location, and at least one location adjacent to the tissue location.

10. The system of claim 1, wherein the handpiece is adapted to form an exit orifice and operatively connected to the beam guidance system for delivering the laser beam to the hard treatment area.

11. The system of claim 10, wherein the handpiece further comprises a focusing optic and at least one optical lens, wherein the at least one optical lens is disposed between the beam guidance system and a tip.

12. The system of claim 11, wherein the at least one lens comprises two lenses.

13. The system of claim 11, wherein the focusing optic and the at least one lens are configured to increase a diameter of the laser beam.

14. The system of claim 11, wherein the focusing optic and the at least one lens are configured to generate a collimated laser beam.

15. A method for treating a treatment area of hard tissue, the method comprising the steps of: generating a plurality of laser pulses of a laser beam having a wavelength from about 9 μm to about 10 μm using a CO.sub.2 laser source; and directing the plurality of laser pulses to respective tissue locations within a treatment area.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the following description, various embodiments of the present invention are described with reference to the following drawings, in which:

[0051] Figure (FIG.) 1 is a side schematic view of a laser based treatment system, including a handpiece, a consumable tip and an optical insert, according to various embodiments.

[0052] FIG. 2 is a side cross-sectional schematic view of a handpiece, according to various embodiments.

[0053] FIG. 3 is a side view providing an example laser treatment, during which the bubble is created in a sealed root canal phantom filled with liquid, according to various embodiments.

[0054] FIG. 4 is a view providing example of ray tracing modeling of the laser beam focused by the optical insert 3, according to various embodiments.

[0055] FIG. 5 is a chart providing example laser treatment and operation parameter values, according to various embodiments.

DETAILED DESCRIPTION

[0056] Various embodiments of the present invention are directed to an improved laser treatment device that overcomes the shortcomings of conventional methods for root canal disinfection. The device can include a hand piece with a special tip that delivers (i) laser pulses that induces bubbles in the fluid to remove the smear layer and (ii) a laser beam having a focused beam, (iii) liquid (e.g., saline, hydrogen peroxide) to an oral treatment region and (iv) delivery system for the irrigant.

[0057] FIG. 1 is a side schematic view of a laser based treatment system, according to various embodiments. In some embodiments, the laser based treatment system includes a handpiece 1, an optical element (e.g., a consumable tip 2 and/or an optical lens), and an optical insert 3. In some embodiments, the handpiece 1 includes a laser source to generate a plurality of laser pulses of a laser beam (e.g., a focused laser beam). For some applications, as described herein, a laser source (e.g., a CO.sub.2 laser source) operating at a wavelength in a range of 9-11 μm (e.g., 9.3 μAm), is desirable for such treatments.

[0058] In some embodiments, the handpiece 1 includes at least a focusing optic and at least one optical lens (e.g., 1, 2, 3, 4, 5 or more lens), where the optical lens is disposed between the beam guidance system and a tip (e.g., the consumable tip 2). When the laser based system is in operation, the focusing optic and the optical lens are configured to adapt (e.g., increase or decrease) a diameter of the laser beam and/or to generate a collimated laser beam.

[0059] In some embodiments, the delivery of the laser beam is achieved by the handpiece 1, which may be structured and designed to receive the optical element, e.g., the consumable tip 2. In some embodiments, the plurality of laser pulses include at least one laser irradiation energy level (e.g., fluence), and the laser irradiation energy level (e.g., fluence) creates a pressure wave and induces agitation or cavitation of irrigants in the root canal. In some embodiments, the laser irradiation energy level of a laser pulse of the plurality of laser pulses is no more than about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, or 5 J/cm.sup.2. In preferred embodiments, the laser irradiation energy level of a laser pulse of the plurality of laser pulses is no more than about 1 J/cm.sup.2. In some embodiments, a laser pulse of the plurality of laser pulses includes a duration from about 0.1 μsec to about 1000 μsec, from about 0.2 μsec to about 500 μsec, from about 0.5 μsec to about 500 μsec, from about 1 μsec to about 500 μsec, from about 1 μsec to about 200 μsec, or from about μsec 1 to about 100 μsec. In preferred embodiments, a laser pulse of the plurality of laser pulses includes a duration from about 1 μsec to about 100 μsec.

[0060] In some embodiments, the optical element is configured to adapt the laser beam such that the plurality of laser pulses are delivered into a treatment site at the endodontic canal. For example, the consumable tip 2 can include at least one optical lens (or optical insert) 3 to modulate a laser beam passing therethrough. The ability to replace or remove the consumable tip 2 allows switching the laser between treatment modes, such as an ablative mode to a non-ablative mode and vice versa.

[0061] In some embodiments, the optical insert 3 provides: (i) seal to the tip such that no capillary force pulls the liquid into the tip and/or (ii) flexibility in obtaining a focusing beam at different locations and laser energy levels to provide optimal treatment efficacy. The laser irradiation energy level (e.g., fluence) can create a pressure wave and induces agitation (or cavitation) of irrigants located within endodontic canals.

[0062] In addition, the laser based treatment system may further include a tubing (or tube opening) 4 in the handpiece 1 throughout the consumable tip 2 to deliver cooling fluids (e.g., air, water, hydrogen peroxide and combinations thereof) to provide fluoride based fluid or a hydrogen based gel ahead of or during the treatment, as shown in FIG. 1.

[0063] In certain embodiments, the CO.sub.2 laser is accompanied with a marking beam (e.g., green in color) that serves as a guidance of the location of the laser beam on the target tissue. In other embodiments, the irradiation of the laser comprises a pattern.

[0064] In some embodiments, the laser based treatment system provides a laser treatment to an endodontic canal to decontaminate, clean, and/or remove at least part of a smear layer of the endodontic canal. In some embodiments, the laser treatment provides a rate of irrigation or movement of irrigants from about 1 millimeters per second (mm/s) to about 20 mm/s. In some embodiments, the laser treatment provides tissue dissolution of the smear layer. In some embodiments, the laser treatment provides a substantially complete removal of the smear layer.

[0065] In some embodiments, the laser based treatment system further includes a beam guidance system disposed in the handpiece 1. In some embodiments, the handpiece 1 forms an exit orifice and is operatively connected to the beam guidance system for delivering the laser beam to a treatment area (e.g., of a hard tissue).

[0066] In some embodiments, the beam guidance system is adapted to direct (and/or repeat directing) the plurality of laser pulses to respective tissue locations in a pattern that includes a plurality of locations. In some embodiments, the pattern includes a plurality of locations including about 1 location to about 5000 locations, about 5 locations to about 5000 locations, about 10 locations to about 2000 locations, or about from about 15 locations to about 1500 locations. In preferred embodiments, the pattern includes a plurality of locations including about 15 locations to about 1500 locations. In some embodiments, the plurality of locations includes at least one tissue location, at least one location non-adjacent to the tissue location, and/or at least one location adjacent to the tissue location.

[0067] FIG. 2 is a side cross-sectional schematic view of a handpiece and a main chamber, according to various embodiments. Examples of such handpiece and associated components are described in U.S. Pat. Nos. 9,622,833 and 10,182,881, which are incorporated herein by reference in their entireties.

[0068] With reference to FIG. 2, a main chamber 11 (FIG. 1) includes a main optical subsystem 13 and a primary fluid supply system 15 affixed to the hand piece 1. In one embodiment, the optical subsystem includes an articulating arm (not shown) through which a laser beam exits toward a first galvanometer mirror 19. The first galvanometer mirror 19 can be attached to a shaft of a first galvanometer 21. The angular orientation in a first axis of the first galvanometer mirror 19 and, therefore, the laser's angle of incidence onto the first galvanometer mirror 19 relative to the first axis is servo-mechanically controlled by the first galvanometer 21. The first galvanometer mirror 19 is generally orientated so that the beam once reflected off the first galvanometer mirror is directed toward a second galvanometer mirror 23, which is attached to a shaft of a second galvanometer 25. The angular orientation in a second axis of the second galvanometer mirror 23 and, therefore, the laser's angle of incidence onto the second galvanometer mirror 23 relative to the second axis is servo-mechanically controlled by the second galvanometer 25. The second galvanometer mirror 23 is generally oriented so that the beam once reflected off the second galvanometer mirror 23 is directed along an optical axis 26, toward and through a first focusing optic 27 that is generally centered along the optical axis 26. The first focusing optic 27 generally has a concave curvature. In some embodiments, the first focusing optic 27 defocuses the beam, increasing the beam width as the beam is directed toward and through a second focusing optic 29 that is also generally centered around the optical axis 26. The second focusing optic 29 can have a generally convex curvature and may be larger in diameter than the first focusing optic 27 to allow for the increased beam width. The curvatures and locations of the first and second focusing optics 27 and 29 can be selected such that the beam is focused outside the hand piece at a selectable distance from an orifice thereof.

[0069] FIG. 3 is a side view providing an example laser treatment, during which the bubble is created in a sealed root canal phantom filled with liquid, according to various embodiments. In some embodiments, the laser treatment is a bench top testing using a prototype handpiece for creating bubble and fluid movement inside a mockup of a root canal.

[0070] As shown in FIG. 3, during a laser treatment as described herein, a laser beam (e.g., a laser beam created by a handpiece 1) can pass through the consumable tip 2 and be focused by the optical inset 3 to provide laser energy to a liquid filled endodontic canal (or root canal phantom 5). The laser irradiation energy level (fluence) can create a pressure wave and induce agitation (or cavitation) of liquid (e.g., irrigants including ethylenediaminetetraacetic acid (EDTA) and/or sodium hypochlorite in water solutions) located within the endodontic canal by generating microscopic bubbles 6 so as to achieve decontamination, cleaning, debriding, and/or disinfecting of the root canal.

[0071] FIG. 4 is a view providing example of ray tracing modeling of the laser beam focused by the optical insert 3, according to various embodiments. For example, FIG. 4 is a simulation of an optimized laser beam being focused by the optical inset to provide optimal efficacy of laser energy transfer inside the liquid (e.g., an irrigant). In some embodiments, the laser treatment and/or operation parameters used in the simulation as shown in FIG. 4 are included in FIG. 5, as described in detail herein.

[0072] FIG. 5 is a chart including example laser treatment and operation parameters, according to various embodiments. Laser parameters (e.g., power, repetition rate, pulse duration, and laser beam overlap) may be configured to have an optimal outcome efficiency to remove carbonate without damaging the material (i.e., optical cartridge or lens) itself. In some embodiments, the laser source may be spatially scanned to provide different pulse energy at different locations of a root canal, as will be appreciated by those skilled in the art.

[0073] Each numerical value presented herein is contemplated to represent a minimum value or a maximum value in a range for a corresponding parameter. Accordingly, when added to the claims, the numerical value provides express support for claiming the range, which may lie above or below the numerical value, in accordance with the teachings herein. Every value between the minimum value and the maximum value within each numerical range presented herein (including in the chart shown in FIG. 5), is contemplated and expressly supported herein, subject to the number of significant digits expressed in each particular range.

[0074] Having described herein illustrative embodiments of the present invention, persons of ordinary skill in the art will appreciate various other features and advantages of the invention apart from those specifically described above. It should therefore be understood that the foregoing is only illustrative of the principles of the invention, and that various modifications and additions can be made by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, the appended claims shall not be limited by the particular features that have been shown and described but shall be construed also to cover any obvious modifications and equivalents thereof.