Apparatus and method for endodontic treatment

An apparatus for endodontic treatment, comprising: a nozzle connected to a fluid source comprising: a tip small enough to be inserted into a pulp chamber of a tooth; an inner geometry which forms a flow parameters including non-axial flow direction of nozzle fluid flowing through the inner geometry such that discharge fluid discharged from the inner geometry increase rotation of root canal fluid within a root canal sufficiently to remove tissue from the root canal.

The contents of the above applications are all incorporated by reference as if fully set forth herein in their entirety.

FIELD AND BACKGROUND OF THE INVENTION

The present invention, in some embodiments thereof, relates to an apparatus and method for endodontic treatment and, more particularly, but not exclusively, to an apparatus and method for treating a root canal using one or more angled fluid jets.

In cases where a tooth is decayed, infected, or abscessed, a root canal procedure may be performed to eliminate infection and decontaminate the tooth. During the root canal procedure, substances such as nerve and pulp tissue are removed in order to prevent future infection.

Current methods for treating a root canal may involve the use of files, such as metal files, for removing tissue such as nerve tissue, magma, pulp tissue or blood vessels from the root canal. In some cases, a rotary file drill is used for shaping a root canal and optionally widening a portion of it to enable access. One of the risks of the use of files for endodontic treatment is the spreading of a smear layer, which may include organic and/or inorganic debris, on the root canal wall after instrumentation. Another potential risk of the use of files may include wounding of the root canal wall or apex.

Endodontic treatment devices have been disclosed by several publications.

U.S. Pat. No. 6,224,378 to Valdes et al. discloses “A method and apparatus for dental procedures using a dental hydrojet tool having a cannula extending therefrom. The cannula is connected to a source of high pressure liquid, and delivers a high velocity, high pressure jet. For root canal procedures, the cannula is directed through an opening formed in the crown of the tooth, and the hydrojet is directed at the pulp, nerve and vascular tissue within the interior chamber.”

U.S. Pat. No. 4,021,921 to Detaille discloses “a device for treating the pulp canals and -chamber of a tooth, the crown of which presents a previously opened pulp-chamber in which said canals open, comprising an apparatus tightly adaptable to the crown of the tooth and providing in the pulp-chamber and the pulp-canals of said tooth for the circulation of a treating solution acting substantially upon the vasculo-nervous bundle or the necroticmagma of the tooth; the pressure of the treating solution being subjected within the pulp-chamber and the pulp-canals to periodical impulses combined to oscillations of substantially higher frequency.”

SUMMARY OF THE INVENTION

The present invention, in some embodiments thereof, relates to an apparatus and method for endodontic treatment and, more particularly, but not exclusively, to an apparatus and method for treating a root canal using one or more angled fluid jets.

According to an aspect of some embodiments of the present invention there is provided an apparatus for endodontic treatment, comprising: a nozzle connected to a fluid source comprising: a tip small enough to be inserted into a pulp chamber of a tooth; an inner geometry which forms a flow parameters including non-axial flow direction of nozzle fluid flowing through said inner geometry such that discharge fluid discharged from said inner geometry increase rotation of root canal fluid within a root canal sufficiently to remove tissue from said root canal.

According to some embodiments of the invention, said flow parameters are sufficient to remove tissue from said root canal including an apex of said root canal. According to some embodiments of the invention, said flow parameters prevent tissue removal in an apical direction of a root canal apex. According to some embodiments of the invention, said at least one discharge fluid jet is at an angle to a vertical axis of said nozzle. According to some embodiments of the invention, said at least one discharge fluid jet enhances a helical flow pattern of said rotation of root canal fluid in said root canal. According to some embodiments of the invention, said inner geometry comprises a lumen and said nozzle fluid circulates along lumen walls, and an exit point of said nozzle fluid is located at a lumen wall at an exit aperture of said nozzle. According to some embodiments of the invention, said nozzle comprises an internal cone and an external cone defining a lumen between them for said nozzle fluid to flow through. According to some embodiments of the invention, said inner geometry comprises a lumen; wherein said nozzle comprises one or more part adapted to move to adjust a geometry of said lumen. According to some embodiments of the invention, an angle of said discharge fluid jet does not intersect a vertical axis of said nozzle. According to some embodiments of the invention, said nozzle fluid comprises liquid and at least one of gas and abrasive powder. According to some embodiments of the invention, a density of a particle of said abrasive powder is larger than a density of other particles comprising said nozzle fluid. According to some embodiments of the invention, said abrasive powder is salt that dissolves following abrasion of said root canal wall. According to some embodiments of the invention, said apparatus comprises one or more inlet connected to a suction source, through which inlet root canal fluid and debris is collected from said root canal. According to some embodiments of the invention, a diameter of said angled discharge fluid jet is approximately 10% of a diameter of an entrance of said root canal or smaller.

According to an aspect of some embodiments of the present invention there is provided an apparatus for endodontic treatment comprising: a nozzle connected to an input pipeline; wherein said nozzle comprises: a tip small enough to be inserted into a pulp chamber of a tooth; and a rotating element disposed inside a nozzle lumen; wherein said rotating element is operable to impart motion to nozzle fluid passing through said lumen such that, after said nozzle fluid is discharged from said lumen, the root canal fluid flows helically within a root canal.

According to some embodiments of the invention, said rotating element comprises an inlet connected to said input pipeline, through which inlet flows at least a portion of nozzle fluid supplied to said nozzle. According to some embodiments of the invention, said rotating element comprises a plurality of blades.

According to an aspect of some embodiments of the present invention there is provided an apparatus for endodontic treatment comprising: a nozzle connected to an input pipeline; wherein said nozzle comprises: a tip small enough to be inserted into a pulp chamber of a tooth; and a inner cone disposed inside a nozzle lumen; wherein said inner cone is adapted to move with respect to said nozzle lumen thereby changing parameters of a nozzle flow through said nozzle lumen.

According to some embodiments of the invention, said nozzle comprises an outer cone and nozzle fluid flow is through a lumen defined between said outer cone and said inner cone.

According to an aspect of some embodiments of the present invention there is provided an apparatus for endodontic treatment comprising: a nozzle connected to an input pipeline comprising: a tip small enough to be inserted into a pulp chamber of a tooth; a lumen; wherein said input pipeline extends into said lumen such that flow of pipeline fluid from said pipeline impinges on walls of said lumen such that said nozzle fluid within said lumen has a helical pattern along walls of said lumen.

According to an aspect of some embodiments of the present invention there is provided an apparatus for endodontic treatment comprising: one or more chamber containing material comprising: one of more of: pressurized gas, fluid and abrasive material; a nozzle comprising a tip small enough to be inserted into a pulp chamber of a tooth; said nozzle shaped to create a beam comprising at least one discharge fluid jet in an angle to a vertical axis of said nozzle, so that said jet flows along a wall of a root canal to remove tissue; and a pipeline connecting said chamber lumen and a nozzle lumen.

According to some embodiments of the invention, the apparatus comprises more than one chamber, wherein each said chamber is connected to said nozzle lumen by a pipe, wherein said beam is at least partially created by said material; wherein material flowing from each chamber mixes within said nozzle lumen. According to some embodiments of the invention, the apparatus comprises a powder cartridge connected between said chamber and said nozzle lumen; wherein said powder cartridge comprises internal cylinders formed with holes of various sizes for filtration of components within said cartridge.

According to an aspect of some embodiments of the present invention there is provided a system comprising: a nozzle comprising a tip small enough to be inserted into a pulp chamber of a tooth; said nozzle shaped to create a beam comprising at least one discharge fluid jet in an angle to a vertical axis of said nozzle, so that said jet flows along a wall of a root canal to remove tissue; and a powder cartridge connected to a nozzle lumen; a pipeline connecting one of a fluid tank and a compressor to said powder cartridge.

According to some embodiments of the invention, said powder cartridge comprises internal cylinders formed with holes of various sizes for filtration of components within said cartridge.

According to an aspect of some embodiments of the present invention there is provided a method for endodontic treatment comprising: discharging at least one fluid jet in a manner which increases speed of rotation of root canal fluid in a root canal, said rotating root canal fluid within said canal removing material from said root canal.

According to an aspect of some embodiments of the present invention there is provided a method for endodontic treatment comprising: placing a nozzle at an entrance to a root canal; discharging at least one fluid jet, from said nozzle, at an angle which causes said fluid jet to flow along a wall of a root canal; and suctioning root canal fluid and debris from said root canal; wherein said discharging and said suctioning are controlled to maintain one or more of root canal fluid flow along said wall, root canal fluid flow at a root canal apex.

According to some embodiments of the invention, discharging and said suctioning are alternating.

According to an aspect of some embodiments of the present invention there is provided a method for endodontic treatment comprising: placing a nozzle at an entrance to a root canal; inserting fluid into a lumen defined between nozzle inner walls and an element adapted to move within said nozzle walls; discharging at least one discharge fluid jet from said lumen at an angle which causes said discharge fluid jet to flow along a wall of said root canal; and changing a geometry of said lumen, by moving said element, to change a velocity of said fluid jet.

According to some embodiments of the invention, said element is an internal cone and said lumen is defined between said internal cone and said nozzle inner walls and changing comprises moving said internal cone with respect to said nozzle inner walls.

According to some embodiments of the invention, moving comprises retracing and advancing said internal cone in the proximal and distal directions within said nozzle inner walls. According to some embodiments of the invention, comprises moving said internal cone in a lateral direction within said nozzle inner walls. According to some embodiments of the invention, moving comprises changing an angle of a vertical axis of said inner cone with respect to a vertical axis of said nozzle inner walls.

According to an aspect of some embodiments of the present invention there is provided an apparatus for endodontic treatment comprising: a nozzle connected to an input pipeline; wherein said nozzle comprises: a tip small enough to be inserted into a pulp chamber of a tooth; a lumen through which fluid flows through the nozzle; and a element located inside said lumen which, when moved, changes a geometry of said lumen thereby changing flow parameters through said nozzle.

According to some embodiments of the invention, said element is a rotating element; wherein said rotating element is operable to impart motion to fluid passing through said lumen. According to some embodiments of the invention, said rotating element comprises an inlet connected to said input pipeline, through which inlet flows at least a portion of fluid supplied to said nozzle. According to some embodiments of the invention, said element is an inner cone; wherein a position of said internal cone is adjustable within said lumen in proximal and distal directions.

According to an aspect of some embodiments of the present invention there is provided an apparatus for mixing particles with fluid comprising: an outer element connected to an fluid source, said outer element comprising a plurality of inlets through which fluid from said fluid source pass; an inner element disposed inside a lumen of said outer cylinder comprising a plurality of inlets through which fluid from said outer element pass into a lumen of said inner element; an outlet connected to said lumen of said inner element; wherein flow of fluid through the apparatus from said fluid source to said outlet collects particles within one or more of said inner element and said outer element.

According to some embodiments of the invention, said outer element inlets and said inner element inlets are different sizes for filtration of one or more of fluid and particles. According to some embodiments of the invention, said powder cartridge comprises internal cylinders formed with holes of various sizes for filtration of components within said cartridge. According to some embodiments of the invention, the method comprises circulating fluid along nozzle lumen walls; wherein discharging comprises discharging said jet from said nozzle from an edge of an exit aperture of said nozzle. According to some embodiments of the invention, discharging and suctioning are balanced to maintain fluid within said root canal. According to some embodiments of the invention, discharging and suctioning are balanced to maintain flow of fluid along root canal walls. According to some embodiments of the invention, pulses are controlled through a control panel electrically connected to said nozzle. According to some embodiments of the invention, discharging and said suctioning includes clearing a root canal to prepare for sealing. According to some embodiments of the invention, removing comprises removing material from tubules extending into said tooth from said root canal.

According to an aspect of some embodiments of the present invention there is provided a method for endodontic treatment comprising: placing a nozzle at an entrance to a root canal; inserting fluid into a lumen of said nozzle; discharging at least one fluid jet from said lumen at an angle which causes said fluid jet to flow along a wall of said root canal; and changing one or more of a shape or size of said lumen to change a velocity of said fluid jet.

According to some embodiments of the invention, changing comprises moving an internal cone inside said lumen. According to some embodiments of the invention, said moving comprises retracing and advancing said internal cone in the proximal and distal directions within said lumen. According to some embodiments of the invention, changing comprises rotating a rotating element inside said lumen. According to some embodiments of the invention, inserting comprises inserting fluid into said lumen through said rotating element.

According to an aspect of some embodiments of the present invention there is provided an apparatus and method for endodontic treatment.

According to an aspect of some embodiments of the present invention there is provided an apparatus for endodontic treatment comprising a nozzle, the nozzle comprising a tip small enough to be inserted through a pulp chamber of a tooth, the nozzle is shaped to create a beam comprising at least one fluid jet in an angle to a vertical axis of the nozzle, so that it flows along a wall of a root canal to remove soft tissue in a helical flow pattern, and the nozzle is connected to an input pipeline. In some embodiments, the nozzle is positionable above an entrance of the root canal such that the vertical axis of the nozzle unites with a vertical axis the root canal. According to some embodiments, the nozzle comprises an internal cone and an external cone defining a lumen between them for the fluid to flow through. According to some embodiments, the nozzle comprises a tube extending between a lumen of the internal cone and the lumen between the internal cone and the external cone. According to some embodiments, the fluid circulates in a helical flow through the lumen for exiting the nozzle in an angle, wherein an exit point of the fluid is located along walls of the nozzle at a location of an exit aperture. In some embodiments, the lumen between the cones is modified by movement of the internal cone with respect to the external cone. In some embodiments, movement comprises retraction and advancement of the internal cone in the proximal and distal directions within the external cone. In some embodiments, movement comprises positioning the internal cone at a different angle with respect the external cone. In some embodiments, a velocity of the flow ranges between 200-300 m/sec. In some embodiments, the nozzle is adapted for discharging at least 1000 angled fluid jets simultaneously. According to some embodiments, the angled fluid jet does not intersect a vertical axis of the nozzle. According to some embodiments, the nozzle comprises channels for creating at least one angled jet. According to some embodiments, there is provided a system comprising: the apparatus, a liquid tank, and an air compressor, wherein the input pipeline of the apparatus passes through a handle to connect the liquid tank and/or air compressor to the nozzle. According to some embodiments, the system is electrically controlled using a control panel configured for operating an electric circuit. In some embodiments, the handle comprises a fusion tank for mixing between liquid, gas, and/or abrasive powder. In some embodiments, the handle comprises a disposable powder cartridge. In some embodiments, the powder cartridge comprises internal cylinders formed with holes of various sizes for filtration of components. According to some embodiments, the fluid comprises gas and/or liquid and/or abrasive powder. According to some embodiments, the gas is air, and the fluid comprises between 50-95% air, and between 5-50% liquid. In some embodiments, a density of a particle of the abrasive powder is larger than a density of other particles comprising the fluid. In some embodiments, the abrasive powder is salt that dissolves following abrasion of the root canal. According to some embodiments, the nozzle is shaped so that the fluid exits the nozzle as an aerosol. According to some embodiments, the apparatus is connected to an air compressor with a pressure ranging between 5-200 PSI. According to some embodiments, the apparatus is connected to a fluid tank which provides fluid at a volumetric flow rate ranging between 0.1-50 ml/sec. According to some embodiments, the angled jet has tangential and vertical velocity components in respect to the root canal wall. According to some embodiments, the apparatus comprises a suction cone for collecting returning fluid and debris, and the suction cone has a tip sized to fit within a pulp chamber of a tooth. In some embodiments, the apparatus is connected to a device suitable for removing the fluid and debris externally to the tooth. In some embodiments, the apparatus is suitable for treating a root canal of a tooth in a human mouth. In some embodiments, a diameter of the angled jet is 10% of a diameter of an entrance of the root canal, or smaller.

According to some embodiments there is provided a method for endodontic treatment comprising discharging at least one fluid jet in a manner which enhances rotation of fluid in a root canal, the rotation sufficient to remove material from a wall of the canal. According to an aspect of some embodiments of the present invention there is provided a method for endodontic treatment comprising discharging at least one fluid jet at an angle which causes it to flow along a wall of a root canal so that the flow removes material from the root canal wall. According to some embodiments, removing comprises separating soft tissue from the root canal wall. According to some embodiments, the flow comprises a helical flow along the root canal wall. According to some embodiments, the root canal comprises at least one narrowing portion, and the flow comprises flowing through the narrowing portion along the wall of the root canal. In some embodiments, the root canal comprises at least one wide portion, and the flow passes through the wide portion along the wall of the root canal. According to some embodiments, the root canal comprises a curvature and/or a branching, and the flow comprises flowing through the curvature and/or the branching. According to some embodiments, the method comprises positioning a nozzle above an entrance to the root canal so that at least one angle fluid jet hits a wall of the root canal. In some embodiments, positioning comprises aligning the nozzle with respect to an entrance of the root canal so that a vertical axis of the nozzle unites with a vertical axis of the root canal.

In some embodiments, the method comprises discharging at least 20000 jets. In some embodiments, the fluid jet merges with fluid contained within the root canal for intensifying a circulating motion of the fluid. In some embodiments, the fluid in the canal has a level reaching to a tip of the nozzle. According to some embodiments, fluid flows along the wall of at least a portion of the root canal so that the fluid returns upwards along at least a portion of a central lumen of the root canal. According to some embodiments, the method comprises eroding a layer of dentin tissue from at least a portion of the root canal wall. In some embodiments, eroding is obtained by abrasive particles of the fluid applying radially outward force onto the root canal. According to some embodiments, the layer has thickness ranging between 100-200 μm. According to some embodiments, the angled jet is created by circulating the fluid in a helical flow within a nozzle of an apparatus. According to some embodiments, the soft tissue comprises nerve tissue, and/or pulp tissue and/or blood vessels. According to some embodiments, the method does not leave a smear layer on the root canal wall. According to some embodiments, directing comprises directing the fluid jets in pulses. In some embodiments, a duration of a pulse ranges between 1-25 seconds, and debris and excess fluid are removed in intervals between pulses. In some embodiments, the pulses are controlled through a control panel electrically connected to the apparatus. According to some embodiments, directing includes clearing a root canal to prepare for sealing. In some embodiments, the components of the fluid rotate about an axis of the angled jet. In some embodiments, the flow removes material from tubules extending from the root canal. In some embodiments, within a root canal dentine wall, a layer of tubules is removed, exposing further tubules which are clean and non-contaminated.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The present invention, in some embodiments thereof, relates to an apparatus and method for endodontic treatment and, more particularly, but not exclusively, to an apparatus and method for treating a root canal using one or more angled fluid jets.

In some embodiments, the apparatus is used for cleaning, abrading, and/or decontaminating a root canal of a tooth before sealing the tooth.

Overview

A general aspect of some embodiments of the invention relates to cleaning and/or abrading a root canal (e.g. in a human tooth within a human mouth) where a flow of fluid, for example a fluid jet (e.g. an angled fluid jet) or a plurality of jets (e.g. a plurality of angled fluid jets) and/or a flow beam and/or a flow cone is discharged hitting fluid within a root canal. In some embodiments, the flow is discharged from a nozzle inserted into the tooth (e.g. into a pulp chamber and/or into a root canal). In some embodiments, the flow from the nozzle (e.g. one or more jet, beam) comprises significant non-axial (e.g. at an angle to a vertical axis of the nozzle) velocity components, for example, more than 10%, more than 30%, more than 50%, more than 90% non-axial components, or lower or higher or intermediate percentages. In some embodiments, the flow from the nozzle includes a small proportion of axial velocity components. In some embodiments, the flow includes less than 60%, or less than 40%, or less than 20%, or less than 10%, or lower or higher or intermediate percentages axial velocity components.

In some embodiments, for example, when the root canal is at least partially filled with fluid, the flow, (e.g. jet/s and/or a beam) hits fluid within the root canal causing and/or intensifying spinning motion of the fluid within the canal. In some embodiments, the jet/s and/or beam increase a speed of rotation of the fluid within the canal and/or a proportion of fluid which is rotating within the canal.

In some embodiments, the flow from the nozzle intensifies spinning of fluid adjacent to the root canal walls (e.g. fluid within 1 mm or 0.5 mm or 0.25 mm or 0.1 mm or 0.01 mm from the root canal walls), for at least a coronal portion of the root canal (e.g. the upper 10%, or 30%, or 50%, or 70%, or 90%, or the entire root canal, or intermediate, higher or lower percentages of the root canal).

In some embodiments, the flow from the nozzle (e.g. one or more jet, beam) does not travel through air after discharge from the nozzle, but may directly hit fluid within the root canal or is contiguous with such fluid (e.g. a nozzle exit aperture is level with or under the surface of fluid within the root canal). In some embodiments, when discharge from the nozzle is contiguous with fluid within a root canal, movement (e.g. rotation) of fluid within the nozzle (e.g. due to viscosity and/or surface tension) causes fluid within the root canal to move, for example, in the same direction and/or with approximately (e.g. within 20% of) the same velocity.

Alternatively, in some embodiments, the flow discharged from the nozzle hits fluid within the root canal indirectly, for example, hitting a portion of the tooth (e.g. root canal wall) before hitting and/or merging with the fluid in the root canal. For example, in some embodiments, the flow discharged from the nozzle passes through an air gap before hitting the fluid in the root canal. In some embodiments, an air gap between a nozzle aperture and fluid in the root canal is measured by a straight line between an exit point of fluid from the exit aperture (or a central point of the aperture) and a point on the fluid level in the canal where discharge hits the fluid in the canal (or a central point on the fluid level in the canal. In some embodiments, the air gap is 0.1 mm, or 0.5 mm, or 1 mm, or 3 mm, or 5 mm or lower, or higher, or intermediate distances.

A general aspect of some embodiments of the invention relates to a nozzle for insertion into a tooth (e.g. a tooth pulp chamber and/or a tooth root canal) where the behavior of material discharged from the nozzle is controlled and/or adjusted by movement of one or more part of the nozzle.

In some embodiments, movement is movement which changes the size and/or shape of a nozzle lumen. In some embodiments, an inner cone moves within a nozzle lumen e.g. with respect to an external cone. In some embodiments, an inner cone moves distally-proximally within the lumen. In some embodiments, an inner cone moves changing an angle of vertical axis of the inner cone with respect to a vertical axis of the nozzle lumen and/or external cone. In some embodiments, reduction of a lumen size increases flow rate and/or pressure of fluid passing through the nozzle.

In some embodiments, one or more part of the nozzle rotates. In some embodiments, the nozzle includes an internal rotating element located within a lumen of the nozzle which stirs and/or moves and/or agitates fluid (e.g. liquid and/or gas and/or abrasive powder and/or nonabrasive powder) passing through the lumen.

In some embodiments of the invention, momentum, potentially including angular momentum, is transferred from the motion of the rotating element to the fluid passing through the nozzle lumen and/or fluid passing through the rotating element before the fluid is ejected from the nozzle: In some embodiments, movement of the rotating element causes fluid with the nozzle lumen to rotate and/or have helical movement. In some embodiments, movement of the rotating element causes fluid in the lumen to flow along the lumen walls, for example, due to centrifugal force applied to the fluid by the rotating element. Potentially, fluid exiting the nozzle does so at an angle which is broadened by the tangential component of its momentum at the exit aperture of the nozzle.

In some embodiments, for example, due to fluid surface tension and/or cohesion between fluid parts, fluid with helical and/or rotational movement within the lumen continues to move with helical and/or rotational movement once discharged from the nozzle (e.g., in an airspace and/or inside the root canal).

In some embodiments, movement of the material is such that, after the fluid is discharged from the lumen, the fluid flows helically within the root canal e.g. due to the angle the discharged jet/beam to the root canal wall, e.g. due to maintaining of helical flow initiated in the nozzle lumen.

In some embodiments, a rotating element stirs fluid in a wide diameter/cross sectional area portion of a nozzle lumen (e.g. the widest 10%, or 30%, or 50%, or 70%, of the nozzle lumen length, or lower, higher or intermediate percentages) and, as the fluid flows distally through the lumen to a nozzle exit aperture, the lumen diameter/cross sectional area reduces (e.g. the lumen is a cone shaped lumen), the fluid continues to rotate.

In some embodiments, the rotating element includes one or more inlet through which fluid (a portion of or all of the fluid passing through the nozzle) flows into the nozzle lumen.

In some embodiments, the rotating element includes blades which are shaped and/or angled such that rotation of the blades pushes fluid towards the nozzle exit aperture.

In some embodiments, a shape of discharged rotating fluid changes upon entry into a root canal, in some embodiments following the shape of the root canal. For example, in some embodiments, discharged rotating fluid flows along the root canal walls (e.g. due to centripetal force of the rotating fluid and/or due to surface tension and/or boundary effects). In some embodiments, rotating of fluid along the root canal walls widens the walls of the root canal optionally increasing a size of the root canal in all three dimensions.

An aspect of some embodiments relates to cleaning and/or abrading a root canal using concurrent control of discharge of fluid into a root canal and removal (e.g. suction by suction) of material from the root canal. In some embodiments flow of fluid and/or pressure is controlled within the root canal. In some embodiments, the root canal is sealed such that material can only enter or exit the root canal through a nozzle (e.g. the root canal is sealed at a coronal opening of the root canal). A potential benefit of sealing is prevention of introduction into the root canal of atmospheric contaminants such as dirt, bacteria. In some embodiments, control of discharge and suction controls a depth (apically) of penetration of fluid and/or a depth (apically) of abrasion and/or pressure within the canal and/or at the canal apex and/or a canal region proximal to the apex and/or a quantity of fluid within the root canal. A potential benefit being reduction of risk of rupture and/or break-through of the root canal at the apex.

In some embodiments, discharge of fluid into the root canal and/or suction of material from the root canal are in pulses. A discharge pulse is a discrete action where discharge is for a time period where before and after the pulse there is no discharge. Similarly, a suction pulse is a discrete action where suction is for a time period where before and after the pulse there is no suction.

In some embodiments, discharge and suction are controlled such that the root canal remains at least partially filled with fluid.

In some embodiments, discharge and suction are in alternating pulses, where a discharge pulse is followed by a suction pulse. In some embodiments, suction and discharge pulses overlap, were there is a time period where both suction and discharge occur. In some embodiments, between discharge and suction pulses there is a pause where there is neither suction nor discharge. In some embodiments, discharge and suction are in simultaneous pulses.

In some embodiments, parameters of discharged fluid from the nozzle (e.g. speed, volume, angular velocity, location of discharge) and/or parameters of suction (e.g. pressure or suction, quantity of material removed, position within the root canal where suction is supplied) are controlled to achieve desired flow characteristics and/or parameters within the root canal, for example, quantity of material within the canal, speed of rotation of fluid within the root canal.

An aspect of some embodiments relates to mixing fluid (e.g. air and/or liquid) with abrasive powder before discharging the fluid including powder from a nozzle. In some embodiments, fluid is passed through (e.g. under pressure) a powder cartridge including powder (e.g. abrasive powder). In an exemplary embodiment, the powder cartridge includes internal cylinders each cylinder including holes for passage of the fluid (e.g. air) through the power cartridge, for example, to mix powder within cylinder/s with the fluid and/or for ejection of components (e.g. abrasive powder) from one cylinder to another cylinder and/or out the powder cartridge. Optionally, in some embodiments, powder cartridge components are non-cylindrical. In some embodiments, the powder cartridge includes internal cylinders each cylinder including holes for filtration of components (e.g. abrasive powder).

An aspect of some embodiments relates to cleaning and/or abrading a root canal using a system including a nozzle where fluid is supplied to the nozzle (e.g. through a pipe) by one or more chamber, for example, within an (optionally disposable) pressurized gas container (e.g. a canister) containing pressurized gas and one or more of fluid and abrasive material. In some embodiments, the nozzle is connected to more than one chamber containing material (e.g. gas and/or liquid and/or abrasive powder). In an exemplary embodiment, the system includes a first chamber containing pressurized gas and fluid and a second chamber containing abrasive powder.

In an additional exemplary embodiment, a system supplies, e.g. using chamber/s containing pressurized gas, more than one flow of material to the nozzle, where the flows meet and/or mix within the nozzle. For example, in some embodiments a first flow includes abrasive powder and gas and a second flow includes liquid. In some embodiments, abrasive powder is mixed with gas and liquid in the container and/or at a container exit.

In some embodiments, a supply apparatus is integrally packaged

In some embodiments, a geometry of the nozzle and/or other parameters such as the fluid composition, the fluid pressure, or others may be selected to achieve the desired conditions (e.g. pressure of fluid flow, speed of fluid rotation and speed/pressure of flow of fluid from the nozzle tip).

In some embodiments fluid flow within the nozzle (and optionally a rotating element) is not exposed to the atmosphere, for example, preventing introduction of contaminants into the tooth and/or preventing degradation of the fluid and/or component/s of the fluid. Degradation being e.g. by atmospheric contaminants such as dirt, bacteria, e.g. by exposure of reactive fluid component/s to atmospheric oxygen.

Optionally, in some embodiments, flow input parameters (e.g. flow rate, flow composition) are varied with rotation to provide desired jet/beam characteristic and/or parameter.

Optionally, a nozzle includes a narrow, needle like tip, for example, providing a narrow beam of jets for cleaning of a narrow root canal and/or providing a focused, high pressure beam and/or facilitating insertion of the tip into a narrow root canal.

Optionally, a nozzle tip (e.g. a needle like tip) includes an angled outlet aperture, or a rounded edged outlet aperture, or any other shape outlet aperture. In some embodiments, a shape of a nozzle outlet aperture changes beam flow characteristics and/or parameters, for example, flow direction, and/or improving acceleration of fluid circulation and/or spinning rate in the root canal. In some embodiments, a shape of nozzle tip is selected to affect flow direction of fluid discharged through the tip, for example, by flow sticking to a surface of the nozzle tip edge, for example a notch, a projection, an angled section.

Optionally, at least a portion of an inner surface of lumen walls is textured (e.g. grooved), potentially assisting and/or enabling helical flow of the fluid e.g. as flow is preferentially in the direction of helical grooves which spiral downward towards a nozzle outlet.

In some embodiments, nozzle structures (e.g. lumens, suction cones, nozzle tip) are cone-shaped. Alternatively, in some embodiments, one or more nozzle structure has a portion with parallel walls, and/or rounded walls (e.g. a straight walled portion terminating in a semi-hemispherical portion). In some embodiments, one or more nozzle structure has a different shape, for example, a nozzle with an outer cone shape and a cylindrical lumen. In some embodiments, an angle of the cone-shaped walls of a nozzle structure to a nozzle structure long axis is 5-75 degrees, or 20-60 degrees, or lower or higher or intermediate angles. In some embodiments, a nozzle has a flattened shape at a nozzle tip. In some embodiments, a cross sectional area of a nozzle tip enlarges distally (e.g. as illustrated inFIGS. 42A-B).

An aspect of some embodiments of the invention relates to cleaning and/or abrading a root canal using one or more angled fluid jets. In some embodiments, once the angled jet hits the root canal wall, the force exerted by the wall channels the jet to travel down the root along the wall. In some embodiments, the angle includes a component outside the plane of the axis of root canal, so that the flow spins in a helical flow along some or all the root canal. In some embodiments, the fluid advances along the root canal wall to remove organic substance and/or abrade the canal wall. In some embodiments, the angled fluid jet does not cross a vertical axis of the root canal and/or a vertical axis of the nozzle. In some embodiments, as described below, an angled jet or a plurality of angled jets are not used, but instead a flow beam than comprises significant non-axial velocity components is used. In some embodiments, the beam does not travel through air when exiting the nozzle, but may directly hit fluid within a root canal or be contiguous with such fluid.

In some embodiments, the jet does not flow straight downwards towards the apex of the root canal. In some embodiments, one or more jet meets the root canal wall at an angle to a plane of the root canal wall where the jet meets the root canal, of 20-45 degrees, or 30-45 degrees, or lower, or higher, or intermediate ranges and/or angles to the root canal wall.

In some embodiments, the passing of the flow through the canal is facilitated by the fluid advancing along the wall. In some embodiments, the flow of fluid passes through a narrowing portion of the root canal to clean and/or abrade the narrowing and/or distal section of the root canal. In some embodiments, the flow of fluid continues to the apex of the root canal. In some embodiments, at least some of the fluid flows back up through the root canal (herein termed returning fluid), washing away soft tissue such as nerve tissue, blood vessels, magma and/or debris. In some embodiments, since the flow of fluid advances along the canal wall, the returning fluid passes upwards through the center of the canal.

Optionally, the resulting flow path allows continual irrigation for cleaning and/or abrading the root canal. In some embodiments, maximum abrasion of the fluid flow is where the fluid flow changes direction, for example, where the flow returns upwards (e.g. in a coronal direction) through the root canal, e.g. at the apex. Alternatively, in some embodiments, for example, due to friction and/or turbulence, as the fluid flows apically abrasion reduces.

Optionally, fluid including liquid and/or gas (including different ratios of liquid to gas) is self-abrasive, for example, where bubbles within fluid abrade the root canal. Optionally, fluid where bubbles abrade the root canal includes nonabrasive powder. In some embodiments, bubbles include powder and/or act as powder and/or are abrasive.

Optionally, irrigation is performed periodically to allow fluid to exit the canal. In some embodiments, a volumetric flow rate of fluid that passes through the root canal ranges between 0.5-50 ml/second, for example between 1-9 ml/second, 30-40 ml/second.

In an exemplary embodiment of the invention, the flow travels along the wall of the root canal for at least 20%, 50%, 70%, 90% or intermediate or greater percentages of the length of the root canal. In some embodiments, flow travels along at least 20%, or at least 50%, or at least 70%, or at least 90%, or substantially all of the surface area of the root canal. In some cases, part of the flow, for example, at the distal end of the canal, includes a significant turbulent flow (e.g., away and towards the wall). In some embodiments, the flow travels a length of 0.1 mm, 0.5 mm, 1 mm, 2 mm, 3 mm along the wall of the canal. Optionally, the flow travels beyond the fluid level within the canal, for example 0.2 mm, 0.6 mm, 1 mm, beyond. In some embodiments, the fluid level is defined as a level which contains 30%, 50%, 70% of fluid vs. an air/void component.

In some embodiments, the direction and/or magnitude of the momentum of the fluid exiting a nozzle of the apparatus is determined by the structure of the nozzle. In an exemplary embodiment, the fluid is circulated in a lumen formed between two cones within the nozzle so that it exits the nozzle in an angle to a vertical axis of the nozzle. In another embodiment, passing the fluid within a structural element of the nozzle, such as an inclined tube configured on a plane that crosses the vertical plane of the tooth may create the angled direction of the jets.

In some embodiments, a flow (e.g. a fast flow) of fluid passes through the root canal and optionally enters at least a portion (e.g. 1%, 4%, 5%, 10%, 20%, 50%, 100%) of the dentinal tubules. In some embodiments, a ratio between gas (such as air) and liquid (such as water, disinfectant, antiseptic medication, and/or any other solution) is used. In one example, a fluid may comprise 90% air and 10% liquid. Other examples include 80% air and 20% liquid, 98% air and 2% liquid, 30% air and 70% liquid. In some embodiments, the selected ratio may affect parameters such as the elasticity of the fluid, the velocity of the fluid, and/or the flow rate. Optionally, components of the fluid such as air bubbles (e.g. pressurized gas bubbles) may facilitate the removal of organic substance from the canal wall and/or erode root canal hard tissue (e.g. dentine). In some embodiments, fluid including bubbles includes nonabrasive powder.

In some embodiments, a relatively low source pressure of the jet or a beam of jets exiting a nozzle is used, for example ranging between 10-200 PSI, 50-100 PSI, 20-30 PSI, 200-300 PSI. In some embodiments, the pressure of the angled jet when hitting a wall of the root canal is lower, for example ranging between 5-150 PSI, 10-30 PSI, 70-120 PSI.

In some embodiments, the fast flow of fluid erodes a layer of tissue, for example dentin tissue. Optionally, eroding is accomplished by adding abrasive particles to the fluid, which are then pushed against the walls of the canal, sweeping away a layer of dentinal tissue, magma, debris and/or bacteria. In some embodiments, eroding of at least or 50-80%, or 20-30%, or 80-90%, or 40-70%, or substantially all of a surface of the root canal wall is performed.

In some embodiments, the flow of fluid smoothes the root canal wall, for example removing grooves. A potential advantage of smooth or groove-free canal walls and/or a lack of a smear layer is that there is no need or there is a reduced need for chemical and/or disinfecting flushes of the root canal.

In some embodiments, a layer of eroded dentine tissue is thin in comparison to traditional root cleaning treatments, a potential benefit being a less invasive treatment and/or a stronger tooth after treatment, and/or less risk of rupturing the root canal. In some embodiments, the layer has thickness ranging between 100-200 μm, or between 40-400 μm, or less than 400 μm.

In some embodiments, the root canal wall is subjected to shear forces exerted by the flow of fluid. Optionally, a thin layer of tissue is removed due to the applied force.

In some embodiments, turbulent flow may be observed in at least a portion of the root canal, for example in proximity to the apex. Optionally, a turbulent flow may increase the shear forces exerted by the flow of fluid. In some embodiments (for example, when fluid is discharged into a root canal containing fluid) a root canal is cleaned and/or abraded by turbulent fluid flow in the canal. In some embodiments, debris and/or eroded material is not pushed into root canal walls, but is pulled away (e.g. into a central portion of the root canal) and/or pushed along root canal walls. A potential benefit being that debris and/or contamination is not pushed into tubules.

In some embodiments, various parameters of the apparatus and/or system such as the angle of the fluid jet, the ratio between gas and liquid, the type of abrasive powder and/or any other parameters or combinations of them may be selected to optimize the effectiveness of the apparatus and/or system. In some embodiments, structural components of the nozzle such as an internal cone within the nozzle are movable with respect to each other. Optionally, the movement modifies a volume of the lumen. In some embodiments, a structure of an internal cone can be modified to change a shape of the lumen, for example by comprising a radially expanding portion which occupies a volume of the lumen. Optionally, the modification of the lumen affects the flow parameters of fluid passing within the nozzle and/or exiting the nozzle.

In an exemplary embodiment of the invention, a plurality of jets are used. Optionally, the use of a plurality of jets allows more freedom (e.g. less manual precision and/or allowing matching to various geometries) in the orientation of the nozzle, as it is more likely that at least one jet will have an angle needed for proper treating of the root canal. Optionally or alternatively, the use of multiple jets may assist in ensuring that all portions of the root canal wall are hit by fluid flow at sufficient velocity and/or other parameters.

In some embodiments, the jets will be contiguous with each other, for example, in the form of a cone and/or a segment thereof. Alternatively, a cone shaped flow is formed without distinct angled jets. Additionally or alternatively, the cone shaped flow or other form of flow comprises a vertical velocity component as well as a circumferential velocity component. Additionally or alternatively, the velocity comprises a radial component. Exemplary ratios of a relative weight of each of the components out of the total velocity may include 70% vertical component, 20% circumferential component, 10% radial component, or 40% vertical, 30% radial, and 30% circumferential, or other ratios thereof. In some embodiments, for example when the root canal is at least partially filled with fluid, the angled jet hits the fluid within the canal. Optionally, the jet merges with the fluid, and may intensify the spinning motion of the flow within the canal. An aspect of some embodiments relates to cleaning and/or abrading a root canal using turbulent flow in the canal. In some embodiments, the turbulent flow is created by providing one or more fluid jets at an angle. In some embodiments, the turbulent flow is created by providing a spinning beam of fluid which merges with fluid within the canal.

In an exemplary embodiment of the invention a turbine such as an air turbine is coupled to an internal pipe within the nozzle, the turbine configured for rotating the pipe so that fluid circulates within the pipe. In some embodiments, the turbine spins a cone of the nozzle which contains the fluid. In some embodiments, the circulating flow of fluid exits the nozzle and enters the root canal, where the spinning momentum may cause the flow the flow along the canal walls, thereby removing tissue.

Various embodiments are described in this application, some of which describe a relation between the nozzle structure and the flow regime within the nozzle, the nozzle structure and the flow within the canal, the shape of the beam and the flow within the canal, desired flow parameters of flow effects in the canal, or others. In an exemplary embodiment of the invention, a geometry of the nozzle and/or other parameters such as the fluid composition, the fluid pressure, or others may be selected to achieve the desired conditions. In some embodiments, a calibration is performed to match up such parameters and achieve a desired effect, optionally using different parameter value sets for different dental conditions. An exemplary device may include a knob which selects different parameter sets determined by such a calibration, and/or according to the selected nozzle geometry.

In some embodiments, a nozzle tip is sufficiently small such that at least a portion of the tip can be inserted into a pulp chamber of a tooth. In some embodiments, a maximum extent of a nozzle tip perpendicular to a vertical axis of the nozzle is less than 0.05 mm, or 0.1 mm, or 0.2 mm or 0.5 mm, or 1 mm, or 2 mm, or 5 mm, or 10 mm, or smaller, or larger, or intermediate measurements.

In some embodiments, tissue is removed from a root canal, for example by rotating fluid within the root canal, at a rate of at least 1 μg/s, or 0.1 mg/s, or 1 mg/s, or 20 mg/s, or lower, or higher or intermediate rates.

In some embodiments, discharge of fluid from a nozzle into fluid within a root canal causes the flow within the root canal to start rotating helically and/or for a speed (e.g. revolutions per second) of already rotating fluid within the canal to increase and/or for a number of revolutions of the fluid along the wall of the root canal to increase.

In some embodiments, fluid in said root canal fills at least 5%, or at least 10%, or at least 20%, or at least 30%, or at least 50%, or at least 90% or lower, or higher or intermediate percentages of a volume of said root canal.

In some embodiments, fluid in said root canal comprises at least 10% liquid, or at least 20%, or at least 30%, or at least 50%, or at least 90% or lower, or higher or intermediate percentages.

A Description of an Endodontic Procedure, According to Some Embodiments of the Invention

Referring now to the drawings,FIG. 1is a flowchart of an endodontic treatment procedure, in accordance with an exemplary embodiment of the invention.

In some cases, for example if a tooth is decayed, infected, and/or cracked, a dentist may decide to perform procedure for treating the root canal of a human tooth, e.g. as described at101.

Commonly, the number of root canals in a tooth depends on the number of the tooth roots, for example ranging between 1-5. In some cases, such as in root canal anastomosis, a single canal may split into branching canals.

In some embodiments, a root canal procedure includes removing pulp tissue (pulpectomy), magma, nerve tissue, and/or blood vessels from the pulp chamber and root canal to prevent future infection and/or an abscessed tooth. In some embodiments, the root canal procedure includes shaping the root canal. In some embodiments, the root canal procedure includes decontaminating the tooth. A feature of some embodiments includes not performing one or more of the above, for example not performing shaping of the root canal.

In an exemplary embodiment of the invention, for example, as will be described below, the root canal is cleaned without leaving a smear layer which, for example, would otherwise block tubules and/or serve as a substrate for infection.

Prior to and/or during the procedure, imaging of the tooth may be performed, as described at103. For example, X-ray imaging may be performed to determine the shape (or number) of the root canals and/or detect signs of infection.

At105, an access cavity to the pulp chamber and root canal is created through the crown of the tooth, for example using a dental drill. Once the access cavity is created, the entrance to the root canal is exposed, as described at107, optionally using a root canal file inserted through the access cavity into the pulp chamber. In some embodiments, access is provided via a side of the tooth. This may be possible if no files are used on the root canal, for example, as described below.

At this stage, in order to clean, shape and/or decontaminate the root canal through the exposed entrance, a distal tip of the apparatus, optionally including a nozzle as will be further described, is inserted through the pulp chamber, as described at109, and an exit aperture of the nozzle is positioned above the exposed entrance to the root canal, as described at111. Optionally, the exit aperture of the nozzle is positioned within the root canal, as will be further described. Optionally, the exit aperture of the nozzle is positioned in an angle to the root canal entrance. At113, one or more angled fluid jets discharged from the exit aperture of the nozzle passes through the root canal, as will be explained by the following figure. In some embodiments, as the flow of fluid advances along the root canal wall, it removes tissue. In some embodiments, the flow of fluid removes organic substance such as pulp tissue, nerve tissue, blood vessels, magma and/or debris from the root canal. In some embodiments, the flow of fluid erodes a thin layer of dentin tissue from the wall of a root canal. In some embodiments, the flow of fluid smoothes the root canal wall. In some embodiments, the flow of fluid disinfects the root canal.

In some cases, manual cleaning (e.g. using a file or other methods known in the art) is used to remove some or all bulk debris from a canal before using fluid jets as described herein. Optionally, fluid jets are used to remove a smear layer created by manual cleaning.

At115, the dentist may optionally evaluate the effectiveness of the cleaning and/or abrading procedure, for example by inserting a file to reach the apex of the root canal and test for remains of infected tissue. Optionally, a dentist may re-wash and/or dry and/or disinfect the root canal (116).

At this stage, sealing of the root canal (and/or the pulp chamber) is optionally performed (117). Optionally, sealing includes filling a hollow interior of the root canal. In some embodiments, a rubber compound such as Gutta Percha material may be used for sealing the root canal. Optionally, the Gutta Percha material is softened and injected into the root canal, in which it then hardens. Alternatively, a more solid form of Gutta Percha, for example shaped as a cone, is inserted into the root canal to fill it. In some embodiments, the sealing process begins by inserting the filling material to the apex of the root canal, and then advancing upwards. In some embodiments, a temporary filling is used, which is later replaced by a permanent filling.

In various acts described above, techniques that are known in the art may be used. The acts described at109-113desirably use an embodiment of an inventive apparatus and method for cleaning and/or abrading a root canal, for example, as described below.

Optionally, the procedure described at101-117is repeated for one or more additional root canals, for example an additional root canal of the same tooth and/or a root canal of a different tooth. Optionally, sealing is performed for the one or more root canals that were treated.

Various types of root canals may be treated using the described methods and/or apparatuses, such as a curved shaped canal, L shaped canal, C shaped canal, S-shaped canal, V-shaped canal, U-shaped canal, isthmus canal, root canal anastomosis, webs canal, fins canal, lateral canal, accessories canal, MB2 canal, root canal type 1-8.

FIG. 2is a flowchart of an exemplary method for cleaning and/or abrading a root canal using one or more angled fluid jets, according to some embodiments of the invention.

At201, one or more angled fluid jets are directed into a root canal to clean and/or abrade it.

In some embodiments, a jet is a directed flow of fluid, optionally exiting from an exit aperture of a nozzle. Different embodiments may have jets with different shapes and/or forms. For example, the jet may have a narrow ray form. In some embodiments, a beam of a plurality of jets is used. In some cases, the jet is thin and flat and may spread out angularly. In other embodiments, a jet is substantially pencil like, but spreads when contacting the root canal wall. In an exemplary embodiment of the invention, the jet shape is determined by the shape of the nozzle used. For example, in some embodiments, the jet/beam shape is determined by the shape of the tip of the nozzle used. For example, in some embodiments, a shape of a jet/beam discharged is the same shape as a shape of the nozzle outlet. For example, in some embodiments, a nozzle with a narrow tip portion (e.g. seeFIG. 9B) discharges a narrow jet/beam. In some embodiments, the shape of the jet may depend on the fluid parameters, such as air/liquid ration and/or pressure and/or pulsatility. In other embodiments, the nozzle may be able to selectively provide one of several jet forms. Optionally, at least a portion of the nozzle is shaped as a needle-like tube, forming a relatively narrow passage for the fluid to flow through.

In some embodiments, each of a plurality of angled jet has hits the root canal wall at a different angle so that the plurality of jets are channeled to flow together along the root canal wall in a helical pattern, as will be further described. In some embodiments, a helical pattern within a nozzle and/or within a root canal is where the path of fluid flow changes angle while flowing apically. In some embodiments, the fluid flow follows a number of revolutions where a direction of the fluid flow repeats, at least in an axis perpendicular to a vertical axis of the root canal.

In some embodiments, the one or more jets are directed into the root canal. In some embodiments, at least a portion of a single jet or a plurality of jets hits the wall of the root canal. In some embodiments, force exerted by the wall channels the jets to advance along the root canal wall. In some embodiments, the fluid flows in a helical flow pattern along the walls of the root canal, for example, as will be further described in the following figure.

In some embodiments, as will be further explained, the one or more jets are discharged from a nozzle such that they are angled to a vertical axis of the nozzle. In some embodiments, the one or more jets enter the root canal such that they are angled to a vertical axis of the root canal. Optionally, the vertical axis of the nozzle unites with the vertical axis of the root canal.

In some embodiments, the shunting of the one or more jets in a specific angle and/or direction is created by a designated inner structure of the nozzle, for example, as will be further explained below.

In some embodiments, a plurality of angled jets such as 2, 4, 8, 12, 50, 1000, 2000, 3000, or any intermediate or higher numbers are used. In some embodiments, the nozzle is adapted for discharging at least 2, or at least 4, or at least 8, or at least 12, or at least 50, or at least 1000, or at least 2000, or at least 3000 angled fluid jets simultaneously. A potential advantage of using a plurality of jets may include a more effective cleaning and/or eroding of the canal wall. For example, in some embodiments, a large number of jets (e.g. more than 5, 10, 50, 100, 300, 1000) means that the entire root canal wall is contacted by the jet. In some embodiments, a larger number of jets and constant liquid flow rate (e.g. jets have a higher proportion of air) results in faster circulation of fluid within the root canal.

In some embodiments, a plurality of jets includes disinfecting material and/or abrasive material.

Optionally, a thickness of the layer of tissue eroded by the flow is substantially equal at various portions of the root canal.

In some embodiments, rotational flow of fluid along the canal walls means that the root canal wall continues to be abraded when the shape of the wall changes due to the abrasion process (e.g. the fluid continues to flow along the canal walls despite changes in shape and/or angle of the walls). In some embodiments, rotation flow of the fluid along the canal walls causes enlargement of the canal in all three dimensions. In some embodiments, abrasion is complex shaped, for example, in a shape other than cylindrical.

In some embodiments, characteristics and/or parameters of the flow and/or fluid (e.g. speed, number of jets, angle of jets, composition of fluid) are changed to be suitable for abrading the root canal during treatment, for example, to maintain erosion as the canal widens. In some embodiments, a proportion of abrasive powder in the fluid and/or a speed of fluid flow is increased during a treatment, for example, so that the root canal wall continues to be abraded as the root canal increases in size (due to abrasion). In some embodiments, abrasion is reduced (e.g. by reducing a proportion of abrasive powder in the fluid and/or a speed of fluid flow) during treatment, for example, to smooth the root canal wall after the majority of the abrasion/erosion has occurred.

In some embodiments, one or more portion of a root canal is smoothed, for example due to fluid flow and/or abrasion.

Another potential advantage of using a plurality of jets includes the ability to select a hitting angle, for example an angle of 30°, 45°, 70° between the angled jet and the root canal wall, and additionally and/or alternatively to assure that at least some of the jets of the beam will hit the root canal wall.

In some embodiments, a single angled jet may be used, for example being narrow enough to effectively advance along the canal wall, creating a thin coating-like layer of fluid. Optionally, in the above described phenomena, the angled jets advance along the canal wall, optionally allowing some or all of the returning fluid to flow back up through a central lumen along the vertical axis of the canal, as will be shown by the following figure. For example, 60-80%, 40-50%, 80-95% of the fluid may flow back through the central lumen, and 10-30%, 5-8%, 30-40%, may flow back up along the canal wall.

In some embodiments, as described at203, the flow of fluid passing through the root canal removes soft tissue such as pulp tissue, magma, nerve tissue, and/or blood vessels. In some cases, the tissue removed is infected tissue. In some embodiments, the flow of fluid flushes away organic substance and/or debris. In some embodiments, flow of fluid cuts soft tissue (e.g. nerves and blood vessels) without pulling the soft tissue from the tooth e.g. a blood vessel is cut in half, with half of the vessel remaining in the tooth. In some embodiments, abrasion removes a layer of dentine, cutting tubules and/or blood vessels within the dentine, optionally including an apical area and/or apex (e.g. cutting blood vessels) of the root canal.

Optionally, a thickness of the layer of tissue eroded (e.g. soft tissue and/or dentine) by the flow (e.g. rotation of fluid within the root canal) is substantially equal at various portions of the root canal. In some embodiments, a thickness of the layer of tissue eroded is between 50-90 μm thick, or between 10-150 μm thick, or between 100-200 μm thick, or lower, or higher, or intermediate thicknesses.

In some embodiments, the flow of fluid erodes a layer of tissue, for example a thin layer, such as a thin layer of dentin tissue. Optionally, the flow of fluid causes widening of the canal. In some embodiment, the flow of fluid smoothes the surface of the root canal wall. For example, the thickness of the eroded layer may range between 100-200 μm, 10-70 μm, 200-300 μm. Optionally, the thickness of the eroded layer and/or the amount of debris removed by the flow depends on various parameters, such as the application time.

In some embodiments, the fluid comprises liquid, such as water and/or antibacterial liquid. Additionally and/or alternatively, the fluid comprises gas, such as air. Optionally, the mixture of air and liquid dispersed from the nozzle is an aerosol. Optionally, the pressure of the aerosol exiting a nozzle ranges between 10-200 PSI.

In some embodiments, a ratio between air and liquid is selected according to the need, for example a ratio between air and liquid may affect the viscosity of the fluid which in turn may affect the velocity of the fluid flowing through the canal.

In some embodiments, the gas is air, and the fluid comprises between 50-95% air, and between 5-50% liquid, or the fluid comprises between 20-95% air and between 5-80% liquid or lower, or higher, or intermediate ratios of liquid to air.

In an exemplary embodiment, the fluid comprises between 60-90% air, and between 10-40% liquid, such as 70% air and 30% liquid, 85% air and 15% liquid, 98% air and 2% liquid, or another higher or lower ratio, or an intermediate ratio.

In some embodiments, composition (e.g. percentage of components within the fluid) of the fluid comprising liquid and one or more of air, abrasive material and disinfecting material is chosen to be suitable for the type of treatment and/or the type of root canal. For example, in some embodiments, a proportion of abrasive powder is increased to increase a rate of erosion of the root canal walls. For example, in some embodiments, disinfecting material is increased and/or added to the fluid at the end of the treatment, e.g. to leave a sterile and/or clean root canal. In some embodiments, for example, if there is a buildup of debris in the root canal, a proportion of gas (e.g. air) in the flow is increased to increase a speed of the flow, for example to flush the root canal from debris. In some embodiments, a proportion of gas in the fluid is reduced for flushing the canal, e.g. as a final stage of treatment.

In another example, the ration between air and liquid is 90% liquid, and 10% air. In another example, the fluid comprises 100% liquid. Optionally, by having fluid with relatively high air content, faster spinning motion may be obtained. Optionally, by obtaining a relatively high angular velocity of the spinning fluid, the radially outward force (i.e. centrifugal force) applied by the flow and/or by particles of the flow such as abrasive powder particles onto the root canal wall is increased. A potential advantage includes eroding a thicker layer of tissue, thereby optionally increasing the treatment effectiveness. Optionally, a friction produced between the gas (e.g. air) components of the fluid when contacting the root canal wall is relatively low with respect to the friction produced by the abrasive particles of the fluid during contact with the root canal wall. In some embodiments, a density of an abrasive particle is higher than a density of a liquid and/or gas particle comprising the fluid. In some embodiments, the percentage of abrasive powder in the fluid ranges between 0.05-15%, such as 0.1%, 2%, 10%, or higher, for example, 20%, 50%.

In some embodiments, eroding of the tissue is achieved by adding abrasive particles such as an abrasive powder to the fluid. Optionally, the abrasive powder comprises between 0.01-3%, 2-2.5%, 0.8-1.2%, 3-8%, 5-7% of the fluid.

In some embodiments, the abrasive powder includes natural/organic material and/or mixed material (e.g. containing more than one component), and/or synthetic material.

In some embodiments, the fluid does not include abrasive powder and abrades the canal itself e.g. in some embodiments, bubbles within the fluid abrade the canal. In some embodiments, abrasive properties of fluid are affected by fluid density and/or viscosity, and/or particle size.

In some embodiments, abrasive particles can change form and/or volume (e.g. dissolve, e.g. absorb fluid to enlarge).

In some embodiments, size and/or proportion and/or composition of abrasive particles affect flow within the nozzle and/or nozzle tip and/or angle jets and/or from the nozzle outlet and/or within the root canal. In some embodiments, abrasive particles size and/or type are selected to be suitable for the type of treatment and/or type of root canal. For example, in some embodiments, large abrasive particles are selected for a canal which requires heavy abrasion. In some embodiments, a temperature of fluid and/or other components (e.g. abrasive powder and/or gas) is selected for the type of treatment and type of canal. For example, in some embodiments, a higher fluid temperature is used for cauterization. For example, in some embodiments, a higher temperature fluid has lower viscosity optionally associated with higher velocity flow, for example facilitating a heavy abrasive particle load with high velocity rotation of fluid. Some examples of abrasive powder that may be added to the mixture of air and liquid include crystallite, silicon powder, garnet powder, aluminum powder, magnesium powder, ceramic powder, plastic powder, synthetic, emery powders, sea shell powder, cement powder, salt, ground seeds, diamond powder, carbide powder, glass powder, iron/iron oxide powder, steel powder, aluminum oxide powder, baking soda, acrylic powder, granite powder, fruit powder, tree shell powder, plant seed powder, sea sand powder, synthetic diamond powder, stone powder, marble powder, copper powder, silica and/or combinations of the above. In some embodiments, the powder grains may have a diameter ranging between 2-500 μm, 10-50 μm, 3-6 μm, 0.1-1 μm, 0.5-2 μm. In some embodiments, the powder grains may be selected according to the type of tissue that is to be removed. In some embodiments, air bubbles can act as an abrasive substance, for example to erode tissue, for example hard tissue (e.g. dentine). In some embodiments, reducing a size of the nozzle lumen increases a number of bubbles within the fluid, generating more abrasion. In some embodiments, pressure of air within the flow is increased, increasing a pressure of the bubbles, increasing abrasion. In some embodiments, the powder may comprise a disinfection component. In some embodiments, the powder particle may generate a disinfection process during the cleaning and/or eroding process in the canal.

In some embodiments, the flow of fluid disinfects the root canal, as described at205, for example by adding disinfectant to the fluid. Optionally, an antibacterial substance and/or medicine is added. In one example, Sodium Hypochlorite is added to the fluid to be passed through the root canal, optionally followed by saline and hydrogen peroxide, to disinfect the root canal. In some embodiments, there are three fluid sources that can be used such as water, disinfectant, and medicine. Optionally, the fluid comprises one or more of these liquids.

In some embodiments, the duration of the process of removing organic substance, eroding the tissue and/or disinfecting the interior of the root canal ranges between 15-45 seconds, for example 20 seconds, 27 seconds, 43 seconds. In some embodiments, for example if the root canal has an extremely narrow portion, the duration of the above process may range between 45-60 seconds, for example 50 seconds, 55 seconds. Optionally, shorter, intermediate and/or longer time periods are required to complete the process. In some embodiments, the treatment is provided in periodic pulses, for example a 10 second duration followed by a 10 second interval, or a 2 second duration followed by a 5 second interval, or another combination of larger, smaller and/or intermediate intervals. In some embodiments, during the interval access fluid is collected from the root canal, for example by suctioning.

In some embodiments, a duration of a pulse ranges between 0.2-0.3, or 0.5-1, or 1-25 seconds, or intermediate values, and, optionally, debris and excess fluid are removed in intervals between pulses. In some embodiments, the pulses are controlled through a control panel electrically connected to the apparatus. In some embodiments, pulses have different durations, and/or flow rates and/or volumes of discharged fluid. In some embodiments 0.1-300 cc/s, or 0.5-155 cc/s, or 0.5-70 cc/s, or any intermediate, larger or smaller ranges and/or values of fluid flow in a pulse.

In some embodiments, suction and/or removal of material from the root canal enables flow of fluid along the root canal wall. For example, because suction empties and/or partially empties the root canal revealing portions and/or the entire root canal wall. For example, because suction creates negative pressure within the root canal, encouraging flow of fluid along the root canal wall.

In some embodiments, suction increases the speed of circulation of the fluid inside the root canal (e.g. due to lack of or reduction in resistance from fluid in the root canal and/or due to reduction of pressure in the root canal). In some embodiments, suction increases the speed of circulation of fluid at the root canal apex and a lower portion of the root canal proximal to the apex.

In some embodiments, suction reduces pressure at the root canal apex and/or an apical portion of the root canal proximal to the apex, potentially reducing the risk of rupture of the apex and/or break-through at the apex.

In some embodiments, the treatment time period and/or the length of the periodic pulses of the treatment are determined according to a ratio between air and liquid in the fluid and/or a ratio between air and powder and/or a ration between liquid and powder. Optionally, operation parameters of the apparatus are determined according to calibrated values.

Application of Fluid by the Apparatus into the Root Canal, According to Some Embodiments of the Inventions

FIG. 3shows angled fluid jets entering a root canal and advancing along the root canal wall in a helical flow, according to some embodiments of the invention.

In some embodiments, angled fluid jet301hits wall303of the root canal305. In some embodiments, the plane in which the angled fluid jet passes before and/or during entrance to the root crosses a vertical plane of the tooth, for example a plane in which vertical axis y passes, as will be explained.

In some embodiments, an angle γ is formed between jet301and an axis extending longitudinally along the canal wall303, such as axis AA. In some embodiments, for example if a portion of the root canal is shaped as a cylinder, axis AA may be parallel to vertical axis y. In some embodiments, angle γ is an acute angle, for example ranging between 10-85 degrees, for example 20 degrees, 45 degrees, 73 degrees. In some embodiments, angle γ is zero.

In some embodiments, one angled jet301or a plurality of angled jets hit the root canal wall. In some embodiments, the jets advance along the root canal wall. In some embodiments, once the jets hit the root canal wall, the force exerted by the wall channels the jets to spin in a helical flow313through the root canal. Optionally, other forms of flow such as longitudinal stream lines along the root canal wall are formed.

Additionally or alternatively, when root canal305is at least partially filled with fluid, for example during steady state operation of the apparatus, angled jet301hits the fluid325within the canal. Optionally, jet301merges with the fluid, and may intensify the spinning motion of flow313within the canal.

In some embodiments, a centrifugal force may be applied to canal wall303by spinning flow313. Optionally, a spiral path of the flow is maintained due to rotational momentum acquired when the fluid is advanced within and/or discharged by the nozzle of the apparatus. Optionally, the spinning pattern of flow313is achieved when a sufficient amount of angled jets enters the canal, such as, 3, 10, 100, 1000, 20000 jets or intermediate, larger or smaller amount, such that the jets merge together to form the helically spinning flow. Optionally, the plurality of applied jets comprise different angles, for example so that they cover the root canal opening circumferentially. Optionally, by hitting the opening circumferentially, a homogenous distribution of the flow is achieved with respect to a periphery of the root canal.

In some embodiments, flow313advances along a portion315of the root canal. In some embodiments, portion315is cylindrical. In some embodiments, flow313passes through a narrowing portion317of the root canal. In some embodiments, flow313passes through a narrowing portion and then through a widening portion. In some embodiments, flow313passes through a curve323.

In some embodiments, narrowing portion317includes a portion having a diameter less than 0.1 mm, less than 0.05 mm, and/or intermediate or smaller values. In some embodiments, curve323has a radius of curvature less than 0.05 mm, less than 0.08 mm, and/or intermediate or smaller numbers. In some embodiments, a length of a root canal past curvature and/or past a narrowing which the fluid flows through ranges, for example, between 0.1-4 mm, for example 1 mm, 0.5 mm, 2 mm.

In some embodiments, flow313reaches apex319of the root canal. In some embodiments, flow313passes through branches of the root canal, for example reaching at least a portion of branching dentinal tubules, (not shown in this figure). In some embodiments, for example if the anatomy of root canal305is unusual, such as an L-shaped or C-shaped root canal, and/or if root canal305has an extremely narrowing portion, flow313may pass through and clean at least most of the canal. A potential advantage of cleaning and/or eroding the root canal using the flow of fluid includes the ability to reach locations such as curves, narrowings and/or branches of the root canal which otherwise would have been impossible or hard to reach, for example when using a file. Optionally, a centrifugal force that is applied to canal wall303by flow313(for example by abrasive powder particles within the fluid) increases a thickness of the eroded layer, thereby optionally increasing treatment effectiveness.

In some embodiments, root canal wall303is subjected to shear forces, which may be applied by flow313. Optionally, due to the shear forces, a thin layer of tissue such as dentin tissue is removed by the flow. In some embodiments, the removal of tissue is homogenous. In some cases, for example in a narrowing and/or curvy portion of the root canal, the removal is non-homogenous. In some embodiments, homogenous removal depends on the diameter of root canal305. For example, in a narrowing having a smaller diameter than 0.1 mm, removal may be non-homogenous. Optionally, in that case, a file may be used for widening the narrowing. In some embodiments, the thickness of the dentin layer removed by the flow of fluid ranges between 10-300 μm, or between 100-200 μm, for example 50 μm, 80 μm, 12 μm. Optionally, intermediate and/or lower thickness layers are removed. In some embodiments, the shear viscosity of the fluid affects the thickness of the removed layer.

In some embodiments, for example, as the root canal is abraded gradually and as, in some embodiments, debris is removed from the canal by the abrading flow, treatment does not result in a smear layer on the root canal walls.

In some embodiments, for example, if a drill has been used to remove material (e.g. generating a smear layer on the root canal walls) removal of material (e.g. a layer of dentine) removes a contaminated layer of material from the root canal

In some embodiments, removal of a layer of dentine, for example a layer 100-200 μm thick of dentine from the root canal reveals tubules.

In some embodiments, a rate of removal is controlled, for example, by applying shorter pulses, for example to prevent perforation. In some embodiments, imaging may be performed, for example during treatment, to decide if additional cleaning and/or abrading is needed.

In some embodiments, flow313reaches apex319of the root canal. In some embodiments, flow313may become turbulent along some portions of the root canal, for example in proximity to apex319.

In some embodiments, flow313erodes apex319, optionally resulting in a duller root canal. In some embodiments, the flow313is applied so that it does not widen a natural opening of the apex, for example ranging between 0.3-0.5 mm, 0.1-0.2 mm, 0.4-0.5 mm. Optionally, treatment duration is selected so that penetration of at least some of the flow through the apex is avoided.

In some embodiments, at least some portion of flow313, optionally including the removed organic substance and/or debris, returns back up through the canal. Optionally, when a lumen of the canal is filled with fluid up to its maximal capacity, at least some of the fluid is caused to exit the canal. Optionally, the amount of fluid that accumulates within the canal before at least some of the fluid is caused to exit the canal is determined by the components of the fluid and their respective amounts, for example determined by the gas-liquid ratio of the fluid. Optionally, fluid accumulating within the canal applies pressure on the apex and/or on the canal wall, and/or on tubulates, and/or branches, and/or on isthmus canals and/or on accessory canals.

Optionally, the flow passes along path321, for example in a central lumen along vertical axis y. A potential advantage of the advancing and returning flow path may include the ability to use a large volume of fluid to clean the root canal. For example, a volumetric flow rate may range between 0.5-50 ml/sec, 10-30 ml/sec, 1-5 ml/sec.

In some embodiments, the velocity of flow313passing through root canal305may be affected by various parameters, such as the ratio between air and liquid of the fluid, the diameter of the root canal (which may vary along portions of the root canal), the viscosity of the fluid, the initial velocity of the fluid in the jet, the angular velocity of the fluid, the vertical velocity of the fluid, the ratio between components such as gas, liquid and powder in fluid, the centrifugal acceleration of the fluid, and/or other parameters or combinations of them. Optionally, the velocity of flow313increases along some portions of the root canal, for example in a narrowing portion. Optionally, the typically conical shape of the root canal, in which a diameter of the root canal decreases, causes the velocity of the fluid to increase as it advances towards the apex. In one example, the velocity of flow313advancing along the root canal wall ranges between 0.5-50 m/sec, 30-80 m/sec, 50-300 m/sec, 10-100 m/sec, 0.6-2 mm/sec, 180-350 m/sec, or any intermediate, larger or smaller ranges. In some embodiments, the flow velocity upon exiting to the atmosphere is, for example, 120 msec. Optionally, the velocity of flow313changes according to a current location within the root canal. For example, rotational flow velocity potentially increases with increasing root canal depth, while axial velocity decreases. In some embodiments, an estimated level of dynamic stress applied during operation of the nozzle within the root canal is about 6 PSI, corresponding to a root canal wall velocity range of about 30-80 msec. In some embodiments, the velocity of the flow enables a relatively high volumetric flow rate, for example 50 ml/sec.

FIG. 4Aillustrates a conical nozzle401positioned above the entrance to root canal403, according to some embodiments of the invention.FIG. 4Billustrates an apparatus comprising conical nozzle401and a handle421, positioned within access cavity423of a tooth above the entrance to root canal403.FIG. 4Cis a geometric representation of an angled fluid jet405.

As seen inFIG. 4A, at least one angled fluid jet405is discharged from nozzle401and directed into entrance407of root canal403.

In some embodiments, for example, as will be further described inFIG. 7, nozzle401includes one or more conical structures. Optionally, nozzle401includes an internal cone411positioned within an external cone413. In some embodiments, circulating the fluid in a lumen between cones411and413creates the angled direction of fluid jet405or a plurality of fluid jets.

In some embodiments, the angled direction of fluid jet405or a plurality of fluid jets is obtained by the conical structure of nozzle401. In an exemplary embodiment, fluid415flows into internal cone411, passes (for example through a slanted tube as will be shown further on) into external cone413, and circulates within a narrowing lumen417between external cone413and internal cone411, until reaching exit aperture419of nozzle401. In some embodiments, the velocity of the fluid is increased and/or decreased when circulating through the lumen, for example by changing the radius of the circulating path.

In some embodiments, the diameter of a portion of nozzle401, for example a diameter of exit aperture419is smaller than a diameter of the root canal opening. In some embodiments, a diameter of the angled jet measured at the exit aperture of the nozzle is 2%, or 5%, or 10%, or 30%, or 50%, or lower, or higher, or intermediate percentages of a diameter of an entrance of the root canal, or smaller. Additionally or alternatively, a diameter of aperture419is smaller than a diameter of the pulp chamber of a tooth. Alternatively, the diameter of aperture419is similar to the diameter of the root canal opening and/or the diameter of the pulp chamber.

In some embodiments, nozzle401and/or exit aperture419of nozzle401are positioned above entrance407to root canal403, for example 1 mm, 7 mm, 1 cm and/or intermediate or higher distances above. In some embodiments, as shown for example inFIG. 4A, exit aperture419is positioned vertically above entrance407such that a longitudinal axis433of nozzle401and a longitudinal axis435of root canal403unite. Optionally, when both axes unite, the exit aperture of the nozzle and the root canal opening act as a unified structure, imposing a similar flow regime of the fluid that advances from the nozzle and into the root canal. Optionally, the velocity of the fluid is maintained when passing between the nozzle and the root canal. In some embodiments, the velocity of the fluid increases, for example if pressure in the root canal is lower than the pressure within the nozzle.

A potential advantage may include irrigating root canal403with one or more angled fluid jets405while nozzle401is positioned directly above entrance407of root canal403. Another potential advantage of discharging angled jets may include preventing the need for a diverting element for causing fluid discharged by the nozzle to contact the root canal wall.

Alternatively, in some embodiments, nozzle401is positioned such that axis433of the nozzle and axis433of the root canal do not unite. Optionally, axis433is parallel to axis435. Alternatively, nozzle401is positioned such that axis433is at an angle to axis435of the root canal.

In some embodiments, a diameter of angled jet405is smaller than a diameter423of exit aperture419. For example, if a diameter of exit aperture419is 0.8 mm, a diameter of fluid jet405for example when passing through exit aperture419may be 10 μm, 90 μm 0.5 mm, 0.1 mm, 0.3 mm, and/or intermediate or lower diameters. In some embodiments, the diameter of angled jet405changes as it flows between exit aperture419and entrance407to the root canal. In some embodiments, a maximal diameter of angled jet405is 30%, 20%, 10%, 4%, 2%, 0.15%, 1%, 0.2%, or intermediate or smaller percentages of a maximal diameter437of root canal entrance407.

In some embodiments, when a plurality of angled jets405are used, a distance between any pair of angled jets exiting through exit aperture419ranges between 0.01-3 mm, such as 0.05 mm, 0.8 mm, 2 mm. Optionally, this distance affects the formation of a coating-like layer of the flow of fluid advancing along root canal wall421, for example, as described above.

In an exemplary embodiment, a relatively high number of angled jets is discharged by the nozzle, for example ranging between 2000-60,000 jets, such as 3000, 15,000, 45,000, jets. Optionally, a diameter of a single jet out of the plurality of jets in such a case ranges between, 1 μm-2 mm, such as 50 μm, 1 mm, 1.5 mm. In some embodiments, as fluid415circulates within lumen417, a direction and/or magnitude of its momentum are determined by the structure of nozzle401. In some embodiments, one or more parameters are selected (by a dentist and/or manufacturer) to create the designated flow of fluid along the root canal wall for the removal of soft tissue. In some embodiments, these parameters include: the number of angled fluid jets, the pressure of the angled fluid jets, the velocity of the jets, the diameter of the jets, the viscosity of the fluid, the ratio between gas and liquid, the amount of abrasive powder added to the fluid, the duration of the treatment, the positioning of the nozzle, and/or any other parameters or combinations of them. In one example, the velocity and pressure of the fluid jet may be selected so that once the jet hits a wall at the root canal entrance, fluid does not spray beyond the entrance to the root canal, for example in the direction of the crown of the tooth. In some embodiments, parameters may depend on each other, for example the ratio between gas, liquid and/or may affect the viscosity of the fluid.

Table 1, now made reference to, presents a table of parameters describing relative amounts and amounts of flow useable with some exemplary embodiments of the invention, for example, embodiments where fluid discharged from a nozzle intensifies rotation of fluid within a root canal. The mass and volumetric flow rates and air/fluid mix percentages are exemplary. It should be understood that values in ranges between the given values, or higher or lower are also used and/or producible in some embodiments of the invention.

In some embodiments, (e.g. embodiments where fluid discharged from a nozzle intensifies rotation of fluid within a root canal) a pressure of air at an exit from a nozzle aperture is, for example, about 75 PSI. In some embodiments of the invention, a pressure of fluid at an exit from a nozzle aperture is, for example, about 75 PSI. In some embodiments of the invention, the pressures are, for example, about 50-60 PSI, about 60-65 PSI, about 65-70 PSI, about 70-75 PSI, about 60-80 PSI, about 75-100 PSI, about 90-130 PSI, or another higher or lower range of pressures suitable for producing cleansing of the pulp chamber.

Associated, for example, with line 1 of Table 1 are other parameters describing flow through the nozzle in some embodiments of the invention (e.g. embodiments where fluid discharged from a nozzle intensifies rotation of fluid within a root canal). These include a velocity at the slanted tube of about 27 msec (for a 0.8 mm tube exit aperture), corresponding to a tangential velocity of about 24.5 msec, and an axial velocity of about 11.5 msec (for a 25° slanted tube angle). In some embodiments, the flow velocity is 5-10 msec, 10-20 msec, 20-22 msec, 22-25 msec, 24-30 msec, 20-30 msec, 25-40 msec, 35-50 msec, or another larger or smaller velocity. In some embodiments, velocity components (e.g. of flow discharged from the nozzle) are divided between axial and tangential velocities according, for example, to the angle set by the slanted tube and/or an angle set by a lumen of the nozzle (e.g. conical lumen of the nozzle). In some embodiments of the invention, the tangential velocity is, for example, 5-10 msec, 8-15 msec, 10-20 msec, 15-30 msec, 25-35 msec, 20-40 msec, 40-60 m/sec, or another larger or smaller velocity. In some embodiments of the invention, the axial velocity is, for example, 5-10 m/sec, 7-15 m/sec, 8-20 m/sec, 15-22 m/sec, 20-25 m/sec, 22-30 m/sec, or another larger or smaller velocity.

Rotational velocity parameters describing flow through the nozzle comprise (e.g. in embodiments where fluid discharged from a nozzle intensifies rotation of fluid within a root canal), for example, a rotational velocity at the top of the cone of about (2 k-15 k) 8,000-12,000 RPM (optionally in the range of 2,000-4,000 RPM, 3,000-5,000 RPM, 4,000-8,000 RPM, 7,000-13,000 RPM, or 10,000-15,000 RPM, or a larger or smaller RPM) and a rotational velocity at the bottom of the cone of about 95,000 to 135,000 RPM (optionally in the range of 30,000-40,000 RPM, 30,000-50,000 RPM, 40,000-80,000 RPM, 70,000-130,000 RPM, or 100,000-160,000 RPM, or a larger or smaller RPM). These correspond also, for example, to a centrifugal acceleration near the top of the cone of about 150-220 m/s2. In some embodiments, the centrifugal acceleration near the top of the cone is about 100-120 m/s2, about 115-140 m/s2, about 130-150 m/s2, about 140-180 m/s2, about 170-200 m/s2, about 190-220 m/s2, about 210-250 m/s2, or another larger or smaller range of angular velocities. In some embodiments, the rotational speeds are higher or lower by, for example, 10-15%, 12-20%, 17-25%, 20-50%, or another higher or lower range of relative rotational speeds.

In some embodiments of the invention, (e.g. embodiments where fluid discharged from a nozzle intensifies rotation of fluid within a root canal) the mixing of gas and fluid (for example, air and water), contributes to the determination of a Reynolds number at the exit aperture of the slanted tube and/or at other places in the nozzle apparatus and/or external to the nozzle apparatus. In some embodiments for example, the Reynolds number at the exit aperture of the slanted tube is in the range of 22,500 to 49,000 (for a 0.8 mm exit aperture). In some embodiments, the range of Reynolds numbers at the exit aperture of the slanted tube is, for example, about 5,000-12,000, about 10,000-15,000, about 12,000-22,000, about 20,000-30,000, about 28,000-40,000, about 35,000-60,000, about 50,000-85,000, about 80,000-120,000, about 100,000-180,000 or another higher or lower range of Reynolds numbers.

In some embodiments, a desired effect is achieved by selecting various parameters. In some embodiments, a table is used for selection of parameters, where device parameters and/or treatment parameters (e.g. fluid parameters such as fluid speed, fluid pressure, fluid composition, treatment length) are listed based on inputs such as characteristics and/or parameters of a root canal (e.g. diameter, shape, type of tissue to be removed, extent of tissue to be removed).

In some embodiments, a desired effect is achieved by inserting inputs into a function or neural network.

In some embodiments, a desired effect is achieved by changing a portion of the apparatus. For example, in some embodiments, an apparatus includes interchangeable nozzles, where different nozzles are adapted for different treatments and/or desired effect. For example, a different nozzle for a curved root canal, a different nozzle for a straight canal, a different nozzle for abrading a root canal and a different nozzle for flushing a root canal. For example, different a supply apparatus for each of abrading a root canal and smoothing a root canal and flushing a root canal.

In some embodiments, a desired effect is achieved by changing device parameters and/or treatment parameters according to feedback. In some embodiments, feedback is manual, where a user witnesses the treatment and changes parameters based on the visual and/or manually measured parameters. In some embodiments, feedback is automatic, for example, the apparatus includes one or more sensor e.g. thermometer e.g. scale for weighing extracted material from the tooth and, for example, a processing application changes device and/or treatment parameters based on measured parameters.

In some embodiments, (e.g. embodiments where fluid discharged from a nozzle intensifies rotation of fluid within a root canal) one or more jet flows along a wall of the nozzle. In some embodiments, a jet follows a path where the jet exits the nozzle (e.g. through exit aperture419) while in contact with a nozzle wall, for example exiting a nozzle exit aperture at a periphery of the exit aperture. In some embodiments, jet405passes through exit aperture419adjacent to the wall of nozzle401, for example an exit point of jet405from nozzle401is positioned along a periphery of aperture419, defined by the walls of the nozzle. Optionally, jet405does not exit aperture419from a central point of the aperture.

In some embodiments, as seen onFIG. 4B, an access cavity423is created, as previously mentioned, through crown425of the tooth. Optionally, access cavity423passes through layers of dentin and enamel tissue. In some embodiments, access cavity423exposes pulp chamber427. In some embodiments, pulp chamber427is cleaned using the described system and/or method. Optionally, the pulp chamber is cleaned using other means. In some embodiments, the system and/or method as described are used for cleaning and/or abrading any other part of the tooth, but may have special advantages when used for treating a root canal.

In some embodiments, at least a portion of nozzle401passes through access cavity423. In some embodiments, at least a portion of nozzle401is inserted through pulp chamber427. In some embodiments, at least a portion of nozzle401, for example the tip including exit aperture419, is narrow enough to enter into at least a portion of the internal lumen of root canal403.

In some embodiments, nozzle401is connected to a handle421. In some embodiments, an input pipeline passes through handle421and connects to nozzle401, as will be further explained. In some embodiments, handle421is used for maneuvering nozzle401(e.g. a user grasps handle421).

FIG. 4Cis a geometrical representation of angled jet405. In the described figure, angled jet405exits a nozzle at point A, and hits root canal wall at point B. In some embodiments, point B is located on a circumference of the root canal entrance. Alternatively, point B is located below the circumference of the root canal entrance, for example 0.1 mm, 1 mm, 3 mm and/or intermediate distances below.

As shown in this figure, axis x extends along a diameter of the root canal, perpendicular to the root canal wall. As mentioned herein, axis y is vertical axis running longitudinally, for example in parallel to the root canal wall. Axis z is perpendicular to both axis x and y. Line A′B is a projection of angled jet405on the xz plane. In some embodiments, an angle α between angled jet405(line AB) and the xz plane, is a sharp angle, for example an angle between 10-85°, such as 20, 35, 75°. In some embodiments, an angle β between the projection A′B of angled jet AB and tangential axis z is a sharp angle, for example an angle smaller than 90°, such as 20°, 50°, 70°. In some embodiments, the size of angle β affects the path of the flow. A potential advantage of a sharp angle β, for example ranging between 5-10°, 15-20°, includes creating a more effective flow path, in which the flow passes closely along the canal wall. Optionally, the size of angle β may affect the radii of the helical flow through the root canal. In some embodiments, angle β may be selected to encourage adhesion of flow to wall and/or reduce bouncing. Optionally, for example if the longitudinal axis of the nozzle unite with the longitudinal axis of the root canal, as previously mentioned, a similar angle β is formed with respect to exit aperture419of the nozzle (i.e. tangential to the walls of the nozzle at exit aperture419).

In some embodiments, a velocity vector V of angled jet405(line AB) can be described by its three velocity components along the axis, showed in this figure as Vx (along axis x), Vy (along axis y) and Vz (along axis z). In one example, velocity component Vy may be 2-50 m/sec, and the velocity component Vz may be 0.5-25 m/sec.

In some embodiments, additionally and/or alternatively to the angled jets, an axial jet (for example extending in parallel to vertical axis y) may be used.

In some embodiments, the fluid forming jet405and/or components of the fluid rotate around the jet's axis.

In some embodiments, any of the described above ideas and/or methods or combinations them may be implemented in the embodiments described below and/or any other embodiment of the invention.

FIG. 5shows a side view of various outlines of a beam501of angled fluid jets (not shown in this figure), according to some embodiments of the invention. The outlines of the beams shown in this figure describe beams that exit a nozzle503, which have not yet entered a root canal.

In some embodiments, as previously described, a beam of a plurality of angled fluid jets is discharged from nozzle503. In some embodiments, the structure of the nozzle affects the shape of the beam. In some embodiments, the size and/or shape of the tip of the nozzle affects the shape of beam. For example, an elongated tip, as will be further shown, may be used to create a narrower, focused beam of angled jets. Alternatively, a shorter tip may be used to create a more scattered beam of angled jets.

In some embodiments, a diameter505of a beam extends beyond a diameter507of the exit aperture of the nozzle. In some embodiments, as shown in this figure, a diameter of the beam changes, for example increases as the flow advances towards the root canal entrance. Optionally, this outline is created due to opposite angled jets (for example jets exiting from opposite ends of a diameter of the nozzle). In some embodiments, for example as shown in this figure, various beams may have different diameters at a certain axial distance from the exit aperture of the nozzle. For example, diameter505is shorter than diameter509.

In some embodiments, the outline of the beam is the circumscribing shape of the beam. Optionally, the outline of the beam is fully filled with flowing fluid. Alternatively, the outline of the beam is formed with constant spaces, for example between angled jets comprising the beam. Alternatively, the beam is formed with transient spaces.

In some embodiments, a large number of angle jets make up the circumscribed beam. In some embodiments, the circumscribed beam is a symmetric shape, for example, with circular cross-section. In some embodiments, the circumscribed beam, once discharged into a root canal, matches the shape of the root canal.

In some embodiments, for example when an exit aperture of the nozzle is positioned within a lumen of the root canal, the jets of the beam may immediately hit the root canal wall, which may channel the fluid to a helical flow along the wall.

In some embodiments, the designated flow along the root canal wall is a result of the original direction in which the angled jets exit the nozzle, and/or a result of the angle created when the jets hit the root canal.

In some embodiments, at least some of the angled jets flow in the same direction.

In some embodiments, a ratio between air and liquid affects the shape of the beam. Optionally, the fluid density affects the shape of the beam.

In some embodiments, the beam shape is affected by one or more of the following: a vertical velocity component of fluid within the nozzle, an angular velocity component of the fluid within the nozzle, a centrifugal effect formed within the nozzle, a pattern of flow (e.g. circular) within the nozzle, a pressure difference between the nozzle and the atmospheric pressure and/or pressure formed within the canal.

In some embodiments, structural elements such as internal guide tubes within the nozzle may affect the shape of the beam. In some embodiments, the outline of the beam may have other shapes such as, for example, a bottle-neck shape, a cylindrical shape, a bell shape, and/or any other shapes.

In some embodiments, the exit aperture comprises a circular rim. Alternatively, the exit aperture comprises a rim having a different shape, for example elliptical. In some embodiments, at least a portion of the fluid flows adjacent and/or on the walls of the nozzle, for example forming a central portion of the exit aperture in which air exists.

In some embodiments, structural components of the nozzle are movable for example to manipulate a geometry of the beam, for example change a beam diameter.

In some embodiments, the angle jet and/or beam of angled jets exit through a center of the exit aperture. Additionally or alternatively, the jet or beam exit the nozzle while flowing along the walls of the nozzle at the exit aperture.

In some embodiments, the beam is shaped a cylinder, for example having a diameter ranging between 0.2-4 mm, such as 0.3 mm, 1 mm, 2.3 mm. The beam may rotate around its axis. The rotating beam may widen to a conical configuration, comprising one more angled jets which are formed at the external periphery of the beam.

In some embodiments, fluid exiting the nozzle may partially stick to the nozzle walls at the exit aperture. In some embodiments, the beam will be diverted as a result of adhering to the wall.

In some embodiments, the flow forming the beam comprises a turbulent flow regime, which may affect the shape of the beam and/or may divert the beam.

In some embodiments, the beam is shaped as a cone and the flow within the cone flows at an angle. Optionally, the cone is a continuous cone. In some embodiments, the flow does not flow only along a longitudinal axis of the cone, but further comprises a circumferential component, so that it effectively comprises a plurality of angled jets. In some embodiments, the velocity of the fluid determines the angular spread of the cone. For example, the vertical and/or angular velocity component of the fluid may affect the angular spread of the cone. In some embodiments, a pressure difference between the nozzle and externally to the nozzle, for example in the root canal, affects the angular spread of the cone. In some embodiments, the centrifugal acceleration of the fluid within the nozzle affects the angular spread of the cone.

In some embodiments, the cone shaped beam is formed of a single angled jet. Alternatively, the cone shaped beam is formed of a plurality of jets flowing on a plane defined by the cone and/or at an angle to a plane defined by the cone.

In some embodiments, an angular velocity of the flow ranges between 1-300°/sec, such as 1°/sec, 10°/sec, 100°/sec.

In some embodiments, a thickness of the walls of the cone (i.e. flow walls) ranges between 0.01-5 mm, such as 0.03 mm, 0.1 mm, 2 mm, 4.5 mm.

Exemplary Apparatus Structure, According to Some Embodiments of the Invention

FIG. 6Ais a cross section view of an embodiment of an apparatus comprising a handle601and a nozzle603, for cleaning and/or abrading a root canal with one or more angled fluid jets.FIG. 6Bis an outline of the apparatus comprising the handle and nozzle.

In some embodiments, handle601comprises one or more pipes605, optionally passing longitudinally along an internal lumen of the handle.

In some embodiments, pipe605ends at its distal end in an entrance aperture to nozzle603, for example an entrance aperture leading to an internal cone of the nozzle, as will be further described.

In some embodiments, a proximal end607of handle601is configured for manual gripping by a user.

In some embodiments, a distal end609of handle601connected to nozzle603is configured for insertion into a tooth, for example through a pulp chamber, to allow the positioning of an exit aperture of nozzle603above a root canal entrance as previously described. Optionally, handle601comprises a narrowing portion in proximity to nozzle603(not shown in this figure), which may facilitate inserting distal end609through, for example, an access cavity created in a tooth. In some embodiments, a height of the nozzle is small enough to enable its insertion into the mouth, for example ranging between 5-15 mm.

In some embodiments, inner pipe605extends beyond the proximal end607of handle601. Optionally, liquid passes through inner pipe605, for example by being connected at the proximal end to a liquid tank. Optionally, air passes through inner pipe605, for example by being connected at the proximal end to an air compressor. In some embodiments, the fluid comprising both air and liquid passes through pipe605. In some embodiments, two pipes are used, one for passing liquid and the other for passing air. In some embodiments, air and abrasive powder (for example transferred from an abrasive powder tank) pass together through at least one of the pipes. In some embodiments, a pipe may be surrounded by another pipe (co-centered pipes), such that the inner pipe is used, for example, for transferring liquid, and the outer pipe is used, for example, for transferring air. In some embodiments, air, liquid, abrasive powder and/or combinations of them pass through at least one of the pipes through the handle.

In some embodiments, the pipes may connect, for example at the proximal end607of handle601, to create the fluid of air and liquid which then circulates within nozzle603until discharged in the form of angled jets.

In some embodiments, nozzle603has conical structure, for example, as will be explained in the following figure. In some embodiments, nozzle603comprises an internal cone613positioned within an external cone615. In some embodiments, a slanted tube617is used for passing fluid from internal cone613to a lumen between the two cones, for example, as will be explained by the next figure. In some embodiments, the slanted tube617may deflect in any direction within the internal cone. Optionally, one or more additional tube (e.g. additional slanted tubes next to slanted tube617) is used for passing fluid from internal cone613to a lumen between the two cones and/or is located in the region of space above internal cone613.

In some embodiments, nozzle603comprises an additional cone611, for example used for suctioning the fluid returning upwards through the root canal, for example, as will be further explained inFIG. 10. In some embodiments, the sucked fluid may pass through the handle, for example passing in an opposite direction to the air and/or liquid passed into nozzle603. Optionally, the sucked fluid passes through one or more pipes in the handle. Optionally, proximal end607of handle601is connected to a pipe and/or tank and/or any other element used for disposing the sucked fluid.

In some embodiments, the nozzle and/or any components of it and/or the handle may be made of various materials, such as, for example, one or more of stainless steel, titanium, aluminum, anodized coated aluminum, PPM, plastic, or other biocompatible and/or sterilizable materials and/or combination of materials. In some embodiments, at least a part of the nozzle and/or handle is disposable. In an exemplary embodiment of the invention, the nozzle is formed of rigid materials and/or geometries, however, a tip thereof may be made flexible.

In some embodiments, the nozzle may be manufactured and/or used separately from the handle and/or the rest of the system, described below.

In some embodiments, the handle may comprise controls such as on/off button to control the duration of the treatment, a dial to control the ration between air and liquid, etc. In some embodiments, the device comprises a calibration table and settings are selected according to the table.

FIG. 7Ais cross section view of a conical nozzle701, andFIG. 7Ba side view of an internal cone703configured within conical nozzle701, according to some embodiments of the invention.

In some embodiments, nozzle701comprises an internal cone703positioned within an external cone705. In some embodiments, internal cone703and external cone705are connected by a tube, for example a slanted tube or channel707extending between an inner lumen of internal cone703and a lumen709between an external face of internal cone703and an internal face of external cone705.

In some embodiments, external cone705has a cylindrical upper portion711. In some embodiments, external cone705has a recess713for example configured along a face the cylindrical upper portion711, optionally in continuance to a pipe of a handle as described above, for allowing fluid to enter into internal cone703. In some embodiments, the recess may be circular, triangular, rectangular or any shape allowing the flow of fluid through into internal cone703. Optionally, the size and/or shape of the recess is determined according to the size and/or shape of an entrance aperture719to internal cone703.

In some embodiments, external cone705has an exit aperture715, which may be positioned above the entrance to a root canal. In some embodiments, the exit aperture may is circular, for example having a diameter717ranging between 0.3-2 mm. Optionally, the diameter of the exit aperture is determined according to a need, for example according to a diameter of the root canal entrance.

In some embodiments, external cone705comprises a narrow needle-like tip portion737. In some embodiments, the length of narrow needle-like tip portion737ranges between 0.2-7 mm. In some embodiments, narrow tip737(comprising exit aperture715) is inserted into a lumen of the root canal. Optionally, narrow tip portion is inserted to a distance of 0.2 mm, 0.5 mm, 1 mm, 2.5 mm and/or any intermediate or higher distances measured longitudinally from the root canal entrance. In some embodiments, an external diameter of tip portion737ranges between 0.5-2.5 mm, and an internal diameter (optionally being the diameter of the exit aperture, as previously mentioned) ranges between 0.3-2 mm. in some embodiments, the diameter of tip portion737is small enough to allow insertion of tip portion737into at least a portion of the root canal. Optionally, tip portion737is flexible, for example made of flexible material.

In some embodiments, needle like tip portion737, for example shaped as a narrow tube, is made of a disposable material. Optionally, needle like tip portion737can be assembled on the nozzle, for example by a user.

In some embodiments, cylindrical upper portion711is covered by a covering lid721, for example for preventing fluid from exiting through the top of nozzle701.

In some embodiments, covering lid721may be screwed on top of the cylindrical upper portion711.

In some embodiments, internal cone703comprises a cylindrical upper portion723, which may be sized and/or shaped according to cylindrical upper portion711of external cone705.

In some embodiments, internal cone703comprises an entrance aperture719, for example configured along a face of the cylindrical upper portion723. In some embodiments, entrance aperture719is configured in continuance to recess713of external cone705. In some embodiments, the entrance aperture may be circular, triangular, rectangular or any shape allowing the flow of fluid through.

In some embodiments, cylindrical upper portion723fits within cylindrical upper portion711such that no space is formed between them, for example preventing fluid from flowing between the two upper portions of the cones. In some embodiments, a diameter of cylindrical upper portion723is only slightly smaller than a diameter of cylindrical upper portion711. For example, a diameter of cylindrical upper portion723ranges between 2-18 mm and a diameter of cylindrical upper portion711ranges between 3-20 mm.

In some embodiments, a top725of cylindrical upper portion723is open. In some embodiments, if cylindrical portion723of internal cone703extends to the same height as cylindrical portion711, covering lid721may cover both internal and external cones.

In some embodiments, a tip727of internal cone703is closed, to avoid fluid from passing through. In some embodiments, tip727extends to exit aperture715, and/or extends beyond exit aperture715, for example 1 mm beyond.

In some embodiments, a slanted tube707extends between an inner lumen of internal cone703and a lumen709between an external face of internal cone703and an internal face of external cone705. Optionally, the entrance729to slanted tube707serves as the exit aperture for the fluid exiting internal cone703. Optionally, exit731of slanted tube707is configured at the lowest point along a face of the cylindrical upper portion723, such that it leads to lumen709.

In some embodiments, the size of lumen709is determined according to a difference in diameters of narrowing portions733and735of external cone705and internal cone703respectively. For example, an initial diameter of narrowing portion733is 3 mm and an initial diameter of narrowing portion735is 0.3 mm. In some embodiments, a distance between the internal and external cones forming lumen709is constant, for example a distance of 1 mm. In some embodiments, a distance between the internal and external cone changes, for example increases along a vertical axis.

In some embodiments, the flow in lumen709increases in velocity as it advances from the upper part of the lumen (e.g. close to exit731), distally towards the lower part of lumen709.

In some embodiments, fluid, optionally including liquid, air, and/or abrasive powder or combinations of the above, flows through recess713of external cone705, into entrance aperture719of internal cone703, and into a lumen of internal cone703. In some embodiments, as the fluid accumulates within internal cone703, pressure may rise and the fluid may be forced through entrance729into slanted tube707. Once the fluid exits slanted tube707through exit731, the fluid circulates within lumen709between the internal and external cones. Optionally, the circulation is helical. Optionally, as the lumen narrows, the velocity of the flow of fluid increases. In some embodiments, the helical circulation causes the fluid to exit nozzle701through exit aperture715of external cone705in the form of one or more angled fluid jets as describe above. In some embodiments, helical circulation continues once the fluid exits the nozzle, for example, the helical circulation continues in air (e.g. before impact with the root canal wall and/or fluid within the root canal). For example, in some embodiments, helical circulation continues in the root canal. In some embodiments, helical circulation continues due to surface tension of the flow (e.g. jet).

In some embodiments, a suction pulse is short enough in duration so that rotation in the root canal does not stop and/or does not reduce to below 10% of a maximum. In some embodiments, rotation of fluid in the root canal is stopped and/or reduced to zero e.g. by discharge of fluid at an opposing direction to rotation and/or by suction.

In some embodiments, rotating and/or helical movement of fluid within the nozzle continues when the fluid is discharged from the nozzle, and/or continues when the fluid enters a root canal which optionally contains or is full of fluid.

In some embodiments, due to the ratio between air and liquid, for example 90% air and 10% liquid, the fluid entering lumen709is an aerosol. A potential advantage of the aerosol includes reducing the friction created between the surface of the cones and the fluid, which may optionally allow for a higher velocity of the fluid (aerosol).

In some embodiments, any of the cones may be nonsymmetrical and/or otherwise distorted. In some embodiments, a needle-like tube can be assembled onto the nozzle, for example onto the exit aperture.

Exemplary Systems for Treating a Root Canal, According to Some Embodiments of the Invention

FIGS. 8A and 8Bare schematic diagrams of exemplary systems for treating a root canal, according to some embodiments of the invention.

In some embodiments, the system comprises a liquid tank801, for example for storing liquid such as water, disinfectant, and/or medicine. Optionally, more than one liquid tank is used, for example for storing medicine separated from water, or disinfectant separated from medicine. In some embodiments, the capacity of the liquid tank ranges between 0.2-50 L. In some embodiments, the liquid tank may be made of aluminum, steel, plastic, or any material capable of containing the liquid and withstanding air pressure. In some embodiments, liquid tank801may comprise a mixing element, such as a mechanical, hydraulically, or electrical whirling element for continuous mixing of the liquid.

In some embodiments, liquid tank801is connected to an air compressor803. In some embodiments, the air compressor pushes air into liquid tank801. In some embodiments, the pressure created by the air compressor ranges between 5-500 PSI, 1-100 PSI, 100-200 PSI. Optionally, as the air compressor pushes air into the liquid tank, the pressure rises within the tank and liquid is forced through an exit aperture of the tank. In some embodiments, the exit aperture of the tank is connected a handle805of an apparatus as described above, for example connected by a pipe.

In some embodiments, the system comprises a collection tank809. Optionally, collection tank809is used for the returning fluid exiting the root canal, which may comprise organic substance, nonorganic substance, and/or debris. In some embodiments, collection tank809is connected to a pump811and/or to a venturic connector. In some embodiments, the pump is used for suctioning the returning fluid, for example through a suctioning cone of a nozzle (not shown in this figure), through handle805, and through one or more pipes leading to collection tank809. Optionally, a suction cap may be placed on the tooth and/or inside the mouth for collecting returning fluid, saliva, and/or debris.

In some embodiments, as shown inFIG. 8B, a powder tank813is used for storing the abrasive powder. In some embodiments, powder tank813is connected to air compressor803.

Air, liquid, abrasive powder and/or any combinations of them may pass through one or more pipes of the system.

In some embodiments, as shown inFIG. 8A, a pipe connected to air compressor803and a pipe connected to liquid tank801are joined at any point along a path leading to handle805, so that the air and liquid are mixed together before entering handle805. In some embodiments, as shown inFIG. 8B, a plurality of pipes may lead air, liquid, abrasive powder and air, liquid and air and/or any combination of them into handle805. In some embodiments, liquid and air or any other combination may flow through co-centered pipes.

In some embodiments, a pipe includes micro pores, for example allowing air to flow inside but preventing liquid from exiting the pipe.

In some embodiments, any of the above described components and/or combinations of them are passed separately, and mixed together only at a lumen of the nozzle (not shown in this figure).

In some embodiments, a control panel815is used for example for controlling the passing of air, liquid, and/or abrasive powder. In some embodiments, pressure, velocity, volume, flow rate and/or any other parameters may be controlled. In some embodiments, the duration of treatment is controlled using control panel815. In some embodiment, control panel815may be connected to a power supply817.

In some embodiments, two or more components of the system such as the liquid tank, air compressor, pump, and/or any other components are connected by an electrical circuit819. In some embodiments, control panel815is used for activating electrical circuit819to control the functioning of one or more components of the system. For example, an electrical signal may be sent using control panel815to activate air compressor803, to release liquid from liquid tank801, to pass fluid into the handle, open a valve along a pipe or junction, and/or any other functions of the system.

In some embodiments, the system is configured for connecting to a standardized pressurized air and/or gas source which may be available in a dental clinic, for example replacing and/or in addition to air compressor803.

In this figure, the thin lines connecting between components may represent control and/or sensing connections, such as electrical connections, while the thick lines represent a pipeline in which liquid, gas, powder, or any combination thereof are delivered to and from the nozzle.

Various Structures of a Nozzle of the Apparatus, According to Some Embodiments of the Invention

FIGS. 9A-9Dillustrate an embodiment of a conical nozzle901comprising a pipe903, extending between handle905and exit aperture907of nozzle901.FIG. 39, as described above, illustrates an additional exemplary nozzle comprising a pipe.

FIGS. 9A and 9Billustrate two embodiments including pipe903.FIG. 9Bshows conical nozzle901having a narrow tip portion911as previously described.FIG. 9Aconical nozzle901having flat tip portion913.FIG. 9Cis a cross section of a nozzle similar to the one described in the above figures that further includes pipe903.FIG. 9Dis a side view of an internal cone of that nozzle.

In some embodiments, longitudinal pipe903is used for passing air, abrasive powder, liquid and/or combination of them flow through nozzle901. In some embodiments, flowing is performed through pipe903in parallel to a fluid flowing through a main path of nozzle901, as described above.

In some embodiments, a distal portion of pipe903protrudes from exit aperture907. In some embodiments, for example as shown inFIG. 9B, if narrow tip portion911is inserted into at least a portion of the root canal, pipe903may be used for delivering any of the above materials into a location within the root canal.

In some embodiments, pipe903affects the direction of the discharged angled fluid jets by diverting them.

In some embodiments, a proximal end of pipe903is connected to any of the above described components of the system, such the fluid tank, the air compressor, the powder tank and/or any of the pipes.

In some embodiments, the internal and external cones comprising nozzle901include an aperture915for the passing of pipe903, for example configured along a face of the upper cylindrical portion of both cones, such as above or below a recess917and entrance aperture919of the external and internal cones respectively.

In some embodiments, as shown onFIGS. 9C and 9D, pipe903passes on a parallel plain to slanted tube909. In some embodiments, pipe903intersects tube909, for example to enable mixing of the fluid with the substance passing through pipe903.

In some embodiments, nozzle901does not include an internal cone.

FIG. 10Aillustrates a nozzle comprising a suction cone1001, as previously mentioned, andFIG. 10Billustrates a horizontal cross section of the nozzle.

In some embodiments, suction cone1001is shaped and/or sized according to an external cone and/or an internal cone of the nozzle.

In some embodiments, suction cone1001is assembled externally to the nozzle. In some embodiments, suction cone is attached to the nozzle during a molding process.

In some embodiments, other mechanical means such as pins or screws are used for attaching the suction cone.

Optionally, a lumen1011is formed between the narrowing portions of suction cone1001and an external cone1013of the nozzle. In some embodiments, this lumen comprises channels or tubes.

In some embodiments, the distal tip of the nozzle1015protrudes from suction cone1001.

In some embodiments, suction cone1001has one or more exit apertures1005and/or1007. Optionally, exit apertures1005and/or1007are configured along a cylindrical upper portion1009of suction cone1001. In some embodiments, exit apertures1005and/or1007are connected to handle, optionally through pipes. In some embodiments, the pipes are connected to a pump such as a vacuum pump for sucking the returning fluid upwards through the nozzle and through the handle to dispose it, as previously described inFIG. 8.

In some embodiments, the sucked fluid may pass through suction cone1001in a lumen between an internal face of the suction cone and an external face of the external cone of the nozzle. In some embodiments, if the lumen comprises channels or tubes, the fluid may be sucked directly through the tubes.

In some embodiments, the fluid returning upwards through the root canal may contain the removed organic and/or inorganic substances such as pulp tissue, nerve tissue, blood vessels, abrasive powder, and/or other debris removed by the flow.

In some embodiments, suction cone1001is covered by a lid, which is optionally screwed on top of a lid of the external cone of the nozzle to prevent fluid from exiting through the top of suction cone1001.

FIG. 10Bshows a horizontal cross section of the nozzle along line AA. A central circular lumen1017is the lumen formed between the internal and external cones. The three arched lumens1019are the lumens formed between the external cone and suction cone1001. In some embodiments, a space1021between arched lumens includes anchors for attaching suction cone1001to the narrowing portion of the nozzle.

FIG. 11A-Bshow two embodiments of a nozzle including one or more directing channels for creating the one or more angled fluid jets, according to some embodiments of the invention.FIG. 11Aincludes a nozzle1101, a horizontal cross section of the distal end of the nozzle1105, and a longitudinal cross section of the nozzle1107.FIG. 11Bincludes a conical nozzle1101, a horizontal cross section1109of the distal tip of the nozzle (exit aperture), and a horizontal cross section1111of the proximal tip of the nozzle.

In some embodiments, a nozzle1101of an apparatus may comprise one or more channels for directing the angled fluid jets. In some embodiments, the channels are formed as tubes1103. In some embodiments, nozzle1101is a cylinder. In some embodiments, tubes1103are configured along the internal wall of nozzle1101.

In some embodiments, an angle of the tube is determined according to a resulting angle of the fluid jet formed by the tube. In some embodiments, the configuration (such as angle) of the tube is adjustable, for example by connecting a back plate of a tube using a screw to the wall of nozzle1101.

In some embodiments, tubes1103have a similar diameter. In some embodiments, tubes1103have various diameters. In some embodiments, a single tube may change in diameter.

FIGS. 12A-12Care drawings of a nozzle comprising at least one valve for controlling the flow through the nozzle, according to some embodiments of the invention. InFIG. 12A, the nozzle has conically shaped outline1219, and inFIG. 12B, the nozzle has an elliptically shaped outline1221. In bothFIGS. 12A and 12B, the nozzle is formed as one piece, for example formed using molding methods. InFIG. 12C, the nozzle may be formed of separate components, for example cones connected together, as will be further explained.

In some embodiments, a valve1201is used for controlling flow, for example the flow of air (or any other gas), liquid, abrasive powder and/or combinations of those into the nozzle. In some embodiments, as shown inFIGS. 12A and 12B, valve1201is positioned between the end of a pipe1203passing through the handle, and the lumen1205formed between an external and internal cones of the apparatus. In some embodiments, as shown inFIG. 12C, valve1201is positioned between the end of pipe1203and a connecting lumen1217. Optionally, when the valve is in open position, a flow of any of the above substances and/or combinations of them enters connecting lumen1217, from which it then passes to lumen1205. Additionally and/or alternatively, at least one valve may be positioned between connecting lumen1217and lumen1205. Additionally and/or alternatively, a valve is positioned at any junction, entrance aperture, exit aperture, along a pipe, a lumen of the nozzle, or any other portion of the nozzle.

In some embodiments, valve1201comprises a sealing element1207. In some embodiments, the sealing element prevents fluid and/or any other substance from flowing upwards into pipe1203.

In some embodiments, valve1201comprises a spring1209. In some embodiments, the spring extends or compresses due to air and/or liquid pressure. In some embodiments, spring1209and/or sealing element1207is controlled using other means, such as mechanical means (for example by connecting valve1201to a lever controlled from the handle), hydraulic means (operated for example by the pressure of fluid passing through) and/or electrical means.

In some embodiments, when spring1209extends, it pulls sealing element1207into an open position. Optionally, in the open position, a material such as air, liquid, abrasive powder and/or combinations of them may flow into lumen1205.

Additionally and/or alternatively, a valve1211is used for controlling the flow of fluid from a lumen of the internal cone into lumen1205between the external and internal cones. Optionally, sealing element1213of the valve is positioned at the end of slanted tube1215. In some embodiments, this valve is used for controlling the treatment duration, for example by periodically pushing the valve to a closed position.

In some embodiments, other elements such as a cord may be used instead of a spring. In some embodiments, only sealing element1207may be used, for example formed as a flap which opens due to air pressure.

A potential advantage of using valve1201or similar includes the ability to add any substance to the fluid immediately before the fluid enters the root canal. In one example, abrasive powder that may dissolve in fluid, such as salt, may be passed (with or without air) through pipe1203, and enter lumen1205. Optionally, since the addition of salt to the fluid is performed at a relatively short time before entering the root canal, a portion of the salt does not dissolve and can be used as abrasive powder for the removal of soft tissue from the root canal.

FIGS. 13A-13Dillustrate a nozzle comprising a cone1301with a pin shaped element1303occupying at least a portion of the internal lumen of cone1301, according to some embodiments of the invention.FIG. 13Bis a horizontal cross section along line AA of the nozzle.FIG. 13Cshows an enlarged view of pin shaped element1303.

In some embodiments, a distal end of tube1305passes into a lumen1307of cone1301which is not occupied by pin shaped element1303. In some embodiments, other elements, for example a cylinder, may be used for occupying a portion of the nozzle, to create a lumen which may be used for flowing fluid in a specific flow pattern and/or direction.

In some embodiments, pin shaped element1303has a diameter smaller than the diameter of cone1301. In some embodiments, fluid passes within lumen1307. In some embodiments, a distance between a face of the rod portion1309of pin shaped element1303and an internal face of cone1303ranges between 0.2-3 mm.

In some embodiments, as seen onFIG. 13A, rod portion1309is shaped as a cylinder comprising a rounded elliptical tip1315. In some embodiments, as seen onFIG. 13D, rod portion1309is shaped as a narrowing cone, having a sharp pointed tip1317.

In some embodiments, a head1311of pin shaped element1303fits within cone1301such that an upper portion of cone1301is fully occupied by head1311. Optionally, this prevents fluid from passing through. In some embodiments, head1311is disposed on a long axis end of rod portion1309. In some embodiments, pin-shaped element is inserted into a nozzle, providing an inner cone (inner cone is not necessarily cone shaped) within the nozzle. In some embodiments, head seals and/or closes a nozzle lumen.

In some embodiments, tube1305may be connected at its proximal end to a pipe in the handle (not shown in this figure). In some embodiments, fluid such as liquid, air, and/or abrasive powder or combinations of them may pass through tube1305. In some embodiments, the fluid circulates within lumen1307, for example in a helical flow. Optionally, the helical flow is caused by rod portion1309, since fluid is forced to pass around it. In some embodiments, the fluid exits the nozzle through exit aperture1313in the form of an angled jet due to the helical flow.

In some embodiments, tube1305has an elliptical cross section1319. Alternatively, tube1305has a circular cross section, a rectangular cross section, or any other shape. In some embodiments, tube1305twists around rod1309, for example adjacent to the rod.

In some embodiments, as seen on13A, cone1301has a narrow elongated tip portion1315. In some embodiments, as seen on13D, cone1301has a flat-shaped tip portion1317.

FIG. 14shows an exemplary assembly of a nozzle, according to some embodiments of the invention.

In some embodiments, the nozzle comprises an internal cone1401, an external cone1403, a suction cone1405, and one or more lids1407. In some embodiments, for example during manufacturing, internal cone1401is inserted into an external cone1403. In some embodiments, internal cone1401is assembled within external cone1403, and optionally both cones are assembled within suction cone1405.

In some embodiments, at least two of the cones are connected by mechanical means, such as pins or screws. In some embodiments, the cones are connected by molding means, for example by casting at least two of the cones together using a designated mold. Optionally, any two and/or all cones are molded together, for example creating a nozzle made of one piece.

In some embodiments, any of the cones is detachable, for example to enable cleaning.

FIG. 15is an illustration of a nozzle including exit flow shaping elements for creating the one or more angled fluid jets. In some embodiments, the exit flow shaping elements may be shaped as wings1505.

In some embodiments, nozzle1503includes one or more wing elements1505.

In some embodiments, wing elements1505are used for diverting the fluid exiting nozzle1503to create one or more angled jets, for example, as previously described.

In some embodiments, the fluid passes in a parallel flow through the cylindrical nozzle1503, and wing elements1505shunt the parallel fluid to an angled direction. In some embodiments, nozzle1503comprises parallel tubes, and wing elements1505are positioned at a distal end of the tubes.

In some embodiments, wing elements1505are configured along an exit aperture of nozzle1503.

Additional Features of the System and/or Apparatus, According to Some Embodiments of the Invention

FIGS. 18A-18Billustrate a conical nozzle configured for modifying a positioning of an internal cone with respect to an external cone, according to some embodiments of the invention. In some embodiments, an internal cone orientation is modified. In some embodiments, an inner cone is non-symmetrical and/or can be rotated. In some embodiments, an inner cone includes at least a portion with textured surface e.g. grooves. In some embodiments, internal cone1801is movable with respect to external cone1803. Optionally, movement of cone1801modifies a volume of lumen1805formed between the cones, for example reducing the volume. Optionally, modifying the volume includes changing an angle of positioning of internal cone1801with respect to external cone1803. In some embodiments, movement of the internal cone reduces the spacing between the cones and increases the pressure and/or the rotation speed and/or the turbulence of the fluid in the lumen.

Optionally, modifying the volume affects the path of fluid. In some embodiments, cone1801is movable along the longitudinal axis of the nozzle, for example movable in the proximal and/or distal directions.FIG. 18Ashows cone1801in a retracted position, closer to a proximal end of the nozzle.FIG. 18Bshows cone1801in an advanced position, closer to a distal end of the nozzle, in which the shape of lumen1805is modified For example, cone1801is advanced towards exit aperture1807of the nozzle, reducing a size of a passage1809formed between the internal and external cones through which fluid advances to exit the nozzle. Optionally, cone1801is advanced in the distal direction by a distance ranging between 0.7-3 mm, or 0.1-0.9 mm, such as 0.3 mm, 0.5 mm, 0.7 mm or any intermediate, larger or smaller ranges and/or values. Optionally, tip1819of cone1801is advanced towards exit aperture1807, and in some embodiments may level with the exit aperture. Optionally, by modifying a shape of lumen1805, for example reducing a size of passage1809, a velocity of fluid circulating between the cones (e.g. vertical and/or angular velocity components of the fluid) is increased. Optionally, by modifying a shape of lumen1805, the fluid pressure of fluid approaching exit aperture1807may change. A potential advantage of increasing a velocity of the fluid circulating within the nozzle and/or within a guide tube assembled onto the nozzle may include increasing the velocity of the flow within the root canal. Optionally, the respective positioning of internal cone1801with respect to external cone1803is determined such as to change the velocity of the fluid circulating between the cones, for example increasing the velocity along some portions and/or decreasing the velocity along other portions of the nozzle. Optionally, the angle of a jet exiting the nozzle is modified as a result of modifying the lumen between the cones. Optionally, a diameter of a jet exiting the nozzle changes as a result of modifying the lumen, for example by modifying the lumen to change a velocity of the flow, which may increase or decrease the jet diameter. Optionally, the jet diameter is determined by the ratio between air and liquid in the flow. In some embodiments, the fluid jet may have a higher velocity, for example as a result of the lumen modification. A potential advantage of a jet having high velocity may include a higher eroding ability of the jet when entering and flowing within the root canal.

In some embodiments, when cone1801is advanced in the distal direction, for example as shown inFIG. 18B, a passage of the fluid is narrowed. If the flow pressure is maintained at a constant level, the velocity of the flow (e.g. the axial velocity component, the vertical velocity component, the angular velocity component and/or the total combined velocity changes. In some embodiments, a change in the angular velocity component and/or a change in the vertical velocity component of the flow may cause a change in the tangential velocity component of the flow exiting the nozzle.

In some embodiments, modifying the lumen changes the angle in which the jet hits the root canal wall and/or hits fluid within the root canal. Optionally, modifying the lumen includes changing a cross section shape and/or size of the lumen, thereby optionally affecting the flow rate.

Various mechanisms can be utilized for moving internal cone1801. For example, a stepper motor1811is utilized for advancing and retracting cone1801along the longitudinal axis of the nozzle. Optionally, internal cone1801is connected to motor1811, which in turn rotates in predetermined intervals for advancing and/or retracting cone1801. Optionally, stepper motor1811is activated through a control panel of the system. In some embodiments, stepper motor1811is coupled to cone1801by a threaded element1817. Optionally, stepper motor1811is configured to rotate a predefined step (i.e. rotate a certain angle) to lower and/or retract cone1801.

In some embodiments, movement of nozzle parts, for example, the internal cone is manual e.g. where a user manually moves one or more part (e.g. by pressing a button mechanism optionally including a spring to move the internal cone).

In some embodiments, as shown at the transverse cross section profile along line BB, a track1813(only a cross section is shown here) extends along a portion of the internal wall of external cone1803. A respective projection1815formed along the external wall of internal cone1801is received within the track, for example for preventing rotation of the cones with respect to each other during advancement and/or retraction of internal cone1801. Optionally, the track prevents rotational movement of the internal cone when threaded element1817is rotated by motor1811.

FIGS. 19A-Billustrate an additional configuration of an internal cone1901movable with respect to external cone1903, according to some embodiments of the invention.FIG. 19Ashows cone1901in a retracted position, closer to a proximal end of the nozzle.FIG. 19Bshows cone1901in an advanced position, closer to a distal end of the nozzle, in which the shape of lumen1905is modified.

In some embodiments, a radial distance between internal cone1901and external cone1903remains constant. Alternatively, the radial distance changes, for example increases and/or decreases, for example decreasing in the proximal direction as shown by the following figure.

In this configuration, advancement of cone1901changes a position of lumen1907in which fluid accumulates before passing through tube1909, with respect to the entrance1911to lumen1907.

In some embodiments, advancing cone1901causes a modification of lumen1905, for example of a distal portion1903. In some embodiments, a passage within portion1913is reduced in size, for example narrowed. The narrowing may cause a change in flow parameters such as: the flow velocity, the flow pressure, the flow rate, the angle of the one or more jets exiting the nozzle, the shape of a beam of jets exiting the nozzle, the flow pattern within the nozzle, speed of circulation/rotation of fluid within the lumen, acceleration of flow within the lumen, or other flow related parameters.

Cross section A-A shows fluid entrance1911leading into lumen1907.

FIGS. 20A-Billustrate an additional configuration of an internal cone2001movable with respect to external cone2003, according to some embodiments of the invention. This configuration also includes a suction cone2005, for example as described above. Optionally, suction cone2005is movable with respect to external cone2003, for example it can be lifted or lowered such as by being connected to stepper motor2007. Optionally, lumen2009between the cones is shaped such that a radial distance between the cones changes, for example with the narrowing of the cone. Optionally, a varying distance between the cones is obtained by the internal cone2001having an angle Θ different than angleof external cone2003. Optionally, one or both angles range between 10-85 degrees, such as 20 degrees, 35 degrees, 60 degrees, 70 degrees or intermediate, larger or smaller angles. In some embodiments, internal cone2001is advanced in the distal direction such that tip2011enters narrow needle portion2013of external cone2003. The modification of lumen2009may cause a change in the axial (vertical) fluid velocity, the angular velocity, the flow pressure, the circular acceleration of the flow, the velocity of the exiting jet (e.g. vertical, angular, and/or tangential velocity components), the angle of the exiting jets, the shape of the beam of jets exiting the nozzle, and/or other flow related parameters.

Cross section B-B shows a locking configuration of internal cone2001to external cone2003, whereby notch2015is received within a respective channel2017for example for preventing rotation of cone2001when motor2007is operated (e.g. rotated a certain step) to advance the internal cone.

FIGS. 21A-Cillustrate an internal cone comprising an expandable portion, according to some embodiments of the invention.FIG. 21Ashows the non expanded configuration,FIG. 21Bshows the expanded configuration, andFIG. 21Cshows a non expanded configuration in which the internal cone is advanced in the distal direction. In some embodiments, internal cone2101comprises at least one portion2103adapted for expanding within lumen2105between the cones. Optionally, portion2103is formed of an elastic material, such as rubber. Optionally, expandable portion2103is configured for extending radially outwards, such as to occupy a larger volume with lumen2105. Optionally, portion2103expands to occupy at least 10%, 30%, 40%, 60% or another larger, smaller, or intermediate percentage of lumen2105. Optionally, expandable portion2103affects the flow of fluid along at least a portion of lumen2105, for example a portion in proximity to the exit aperture of the nozzle. Optionally, by expanding portion2103, the angle of the fluid jet discharged by the nozzle changes, for example a tangential angle of the jet with respect to the exit aperture may be modified. Optionally, by expanding portion2103, the flow rate of fluid passing through may change. Optionally, expansion of portion2103affects the velocity of the flow.

In some embodiments, portion2103is caused to expand by a rigid structure, for example comprising a rod2107, a conical portion2109and a conical tip2111. Optionally, rod2107is coupled only to tip2111. Tip2111may be positioned at various locations within lumen2105.

Optionally, the structure is advanced and/or retracted by a stepper motor2113. Optionally, advancement of the structure in the distal direction causes conical tip2111to press against the elastic walls of expandable portion2103, thereby occupying a larger volume within lumen2105. Optionally, expansion of portion2103is combined with modifying a positioning of internal cone2101with respect to external cone2103, to define a shape of lumen2105.

In some embodiments, cone2115is movable with respect to the external cone, by being coupled to motor2213for example by a threaded element. In some embodiments, by activation of motor2213, radial expansion and/or movement of the internal cone can be obtained, simultaneously or separately.

In some embodiments, a distal portion2115of lumen2105is modified, for example the local expansion of portion2103narrows down the passage in which fluid flows. Optionally, this increases the velocity of the fluid, for example if the fluid pressure is maintained at a constant level. Optionally, this changes the angle in which the one or more jets exit the nozzle. Optionally, parameters such as the flow pressure, fluid velocity, and/or the angular velocity of the fluid within lumen2105, and/or the shape of the beam of angled jets discharged by the nozzle are affected by the modification of lumen2105.

In some embodiments, internal cone2101comprises one or more narrowing portions (not shown in this figure), which may modify a shape of lumen2105.

FIG. 22shows an additional configuration of an internal cone2213comprising an expandable portion2203.FIG. 22Ashows the internal cone in a non-expanded configuration, andFIG. 22Bshows the internal cone expanded radially in the lumen between the cones, in the direction of the external cone. Optionally, expandable portion comprises a smaller cone2201constructing internal cone2213. In this example, the expandable portion2203extends longitudinally within lumen2205so that when expanded radially, it may occupy most of the volume of lumen2205, such as 51%, 70%, 80% or 90% of lumen2205. Optionally, the expandable portion is an elastic layer surrounding cone2201of internal cone2213. In some embodiments, as shown in this figure, the expansion is operated by a rod2207having a proximal end connected to a threaded element2209, which in turn is coupled to a stepper motor2211, and a distal end of the rod is connected to cone2201. Optionally, motor2211is also connected to internal cone2213, for example through a second threaded element2215, for being movable for example in the distal and/or proximal directions within the external cone. Optionally, the distal tip2217of cone2213is advanced is in the distal direction towards exit aperture2219of the nozzle, any may optionally level with the aperture.

In some embodiments, by activation of motor2211, the radial expansion and/or the movement of internal cone2213can be obtained, simultaneously or separately.

In some embodiments, lumen2205is modified by the radial expansion of portion2203. Additionally or alternatively, lumen2205is modified by the movement of cone2213. Optionally, a distal portion of lumen2205, for example in proximity to exit aperture2219, is reduced in volume. The modification of lumen2205may cause a change in the axial (vertical) velocity of the fluid within the nozzle. Additionally or alternatively, the modification of lumen2205may cause a change in the angular velocity of the fluid within the nozzle. Additionally or alternatively, the modification of lumen2205may cause a change in the angle of the jet exiting the nozzle.

In some embodiments, the modification of lumen2205is changed to cause a change in the flow regime, for example it is controlled by a dentist. Optionally, lumen2205is modified to suit a certain type of treatment, for example, a modification that causes a beam of jets having a relatively narrow profile or a wide profile may be more efficient when treating a root canal, for example a wide beam may be more suitable for treating a wide root canal, and a narrow beam may be more suitable for treating a narrow or complex canal, such as isthmus or webs canal. A wider beam may be more efficient when treating a complex shaped root canal, for example a root canal having many tubules, a root canal connected to a second root canal (webs canal or isthmus canal), or other canal forms.

FIG. 23Aillustrates a conical nozzle2303comprising one or more internal channels2301, according to some embodiments of the invention. In some embodiments, channels2301are formed in a spiral configuration. Alternatively, channel2301is formed in other configurations such as parallel to the walls of nozzle2303, parallel to a longitudinal axis of nozzle2303, or transversely extending within nozzle2303. In some embodiments, nozzle2301comprises more than one internal channel, such as 2, 4, 6, 8 or a larger or intermediate number. Optionally, a channel conducts a component such as liquid, gas (e.g. air), and/or abrasive powder and/or disinfection material and/or irrigation solutions. In some embodiments, exit aperture2305of channel2301is positioned close to an internal wall of cone2303, so that flow exiting channel2301will flow along the walls of cone2303and optionally circulate at a high velocity along the walls, advancing towards exit aperture2307. In some embodiments, the exit aperture2305of channel2301is positioned in proximity to exit aperture2307of nozzle2303, for example to conduct abrasive powder. Such a channel may be especially useful if a powder that is dissolvable in liquid over time is used, such as salt, in order to mix it into the fluid right before the fluid enters the root canal. Optionally, channel2301is movable with respect to the internal lumen of nozzle2303, for example by being connected at its proximal end to a stepper motor.

In some embodiments, as illustrated inFIG. 23A, channels2301includes more than one channel. In some embodiments, as illustrated inFIG. 23Achannels merge into a single channel and the separate flows merge in a combined channel. In some embodiments, separate flows merge after emerging from separate channel exit apertures e.g. in some embodiments separate exit apertures are in close proximity (e.g. within 1 mm of each other) and the flows mix substantially immediately after emerging from the channels. Merging can occur at any point within the channel and/or nozzle.

Optionally, channel/s2301are movable with respect to the internal lumen of nozzle2302, e.g. distally-proximally and/or by rotation. In some embodiments, movement of channel/s2301is by connection of the channel/s to a stepper motor. In some embodiments, movement of channel/s2301is manual.

FIG. 23Billustrates a conical nozzle combining one or more internal channels2305, a pipe2307movable along a longitudinal axis of the nozzle, and a movable internal cone2309, for example as described herein.

In some embodiments, channel2305, for example having a spiral configuration, conducts liquid, gas and/or abrasive powder and/or disinfection solution and/or irrigation solution. Optionally, channel2305is connected to a pipe configured within the handle, and/or connected to a fluid-receiving lumen2311within the nozzle. In some embodiments, a cross section profile of the channel is circular, for example having a diameter ranging between 0.2-4 mm. Alternatively, the cross section of the channel is elliptical or otherwise shaped.

In some embodiments, channels2305are formed by hollows in a solid component, for example, inner cone2309.

In some embodiments, channels2305are formed by hollows in an non-solid component, for example channels2305being pipes supported by a mesh.

In some embodiments, movable pipe2307delivers at least one of liquid, gas, abrasive powder. Optionally, pipe2307delivers a disinfection solution (e.g. solution including antibacterial agent/s) and/or other medication and/or a flushing solution. In some embodiments, pipe2307is connected to a pipe configured within the handle. Optionally, pipe2307is movable along the longitudinal axis of the nozzle, for example it can be lifted up in the proximal direction (e.g. using the stepper motor) or lowered in the distal direction. Optionally, a distal end2313of pipe2307is positioned in proximity to exit aperture2315. Optionally, the location of distal end2313with respect to external cone2317and/or with respect to exit aperture2315affects the flow of fluid within the nozzle and/or the angle or beam shape of fluid exiting the nozzle. Optionally, movement of pipe2307, the flow within channel2305, and/or movement of internal cone2309with respect to the external cone are combined to form a desired flow regime. Optionally, activation of the one or more components of the nozzle is performed using a controller.

In some embodiments, e.g. as illustrated inFIG. 23B, channel2305includes more than one channel (in the figure two channels are illustrated). In some embodiments channels2305merge into a single channel (inFIG. 23Bchannels2305merge at cross section C-C) and the separate flows merge in a combined channel.

In some embodiments, separate flows merge after emerging from separate channel exit apertures in inner cone2309. In some embodiments separate exit apertures are in close proximity (e.g. within 1 mm of each other) and the flows mix substantially immediately after emerging from the channels.

In some embodiments, inner cone2309includes a portion2309aadapted to move independently from inner cone: For example, to rotate at a different speed and/or in a direction and/or to move distally and proximally independently from inner cone2309.

FIGS. 24A-Bare two configurations of a handle2401comprising a fluid mixer2403for mixing between components of the fluid, such as gas, liquid and/or abrasive powder, in accordance with some embodiments of the invention.

In some embodiments, handle2401comprises a cartridge2405, for example filled with abrasive powder. Alternatively, cartridge2405is filled with liquid such as medication, or any other component and/or particles intended to be delivered into the nozzle. Optionally, cartridge2405is replaceable and/or disposable, for example it can be replaced between patients and/or between treatments. Optionally, cartridge2405is refillable. Optionally, by mixing between components of the fluid within the handle, the need for external containers in which mixing is performed can be reduced, thereby optionally reducing the number of system components In some embodiments, the volume of the cartridge ranges between 0.5 CC-20 CC.

FIG. 24Ashows a pipe2407configured for delivering air and/or powder into the nozzle, in accordance with some embodiments of the invention. Optionally, a valve is placed for example at the entrance to the nozzle to control the flow. Pipe2409, also leading into the nozzle, may deliver air and/or powder, or liquid, into the nozzle. Pipe2411connects to fluid mixer2403, and delivers, for example liquid. Pipe2413connects to fluid mixer2403, delivering, for example, air and powder. In some embodiments, flows from pipes2411,2413mix within fluid mixer2403(e.g. the flows mix uniformly to produce a uniform composition flow exiting the mixer).

Pipe2423is a suction pipe which delivers fluid and/or debris in an opposite direction from the nozzle. In some embodiments, each of pipes2407,2409,2413,2411deliver one or more of gas (e.g. air) and/or fluid and/or powder and/or disinfection solution and/or irrigation liquid. In some embodiments, flows from pipes2407,2409,2413,2411join and mix in a lumen2425(e.g. a region of lumen2425proximal to a nozzle exit aperture) of a nozzle2427before passing out of nozzle2427through a nozzle exit aperture.

InFIG. 24B, suction pipes2415lead fluid and/or debris away from the nozzle, pipe2417leads air and/or powder into cartridge2405. The air and powder may be mixed within cartridge2405at dry conditions, where no moisture or humidity exist. Optionally, a valve is installed at junction2419for example for preventing fluid from fluid mixer2403entering cartridge2405. Pipe2421leads fluid into fluid mixer2403where, in some embodiments, flow from pipe2421and flow from cartridge2405merge and flow into mixer2403for mixing. The mixed flow including liquid, air and abrasive powder then flows from mixer2403into the nozzle lumen2427. In some embodiments, each of pipes2417,2421deliver one or more of gas (e.g. air) and/or fluid and/or powder and/or disinfection solution and/or irrigation liquid.

The above exemplary pipeline configurations can be coupled to any type of nozzle, such as, for example, described herein.

FIGS. 25A-Cillustrate various configurations of a powder cartridge supply system, according to some embodiments of the invention. Optionally, the cartridge is disposable. Optionally, the cartridge is replaceable, and can be assembled or detached from the handle for example through a designated opening. In some embodiments, the powder cartridge supply system is configured for supply and mixing abrasive particles with gas immediately before the fluid enters fusing tank (e.g. fluid mixer2403) before entering the nozzle. Optionally, the cartridge comprises a predefined amount of abrasive powder, for example suitable for performing 1, 3, 5, 10 or another number of treatments.FIG. 25Ashows abrasive powder2501contained within the cartridge, prior to mixing with gas. The cartridge comprises a cylinder formed with a plurality of internal cylinders, as will be explained inFIG. 25C. Optionally, the one or more internal and/or external cylinders comprise holes. Optionally, the one or more cylinders are coated with a flexible cover.

FIG. 25Bshows powder2501once gas and/or liquid have entered the cartridge, and the cross section B-B shows the direction in which air flows into the inner lumen2513for mixing with the powder. In some embodiments, a volume of the cartridge ranges between 0.2-10 cc, 5-15 cc, 10-25 cc, 25-60 cc, or intermediate, larger or smaller volumes. In some embodiments, the cartridge is formed of a metal, PPM, plastic, or any material that can withstand the pressure.

In some embodiments, gas such as air is compressibly forced into the cartridge, for example through opening2509. In some embodiments, air is forced into the cartridge at a pressure ranging between 2-300 PSI. In some embodiments, the compressed air generates a circulation, turbulence or other swirling motion of the powder within the cartridge.

In some embodiments, as shown for example inFIG. 25C, the cartridge comprises one or more cylinders positioned one within the other. Optionally, the cylinders comprise one or more openings2503,2511,2505for enabling the passing of certain components through and blocking the passage of other components through. Optionally, a diameter of an opening may range between 40 μm-300μ, or 100 μm-2 mm or 20 μm-5 mm. For example, an internal cylinder2505may be formed with holes that allow powder2501to exit through in the radial direction, for example when air flows into the cartridge. Optionally, external cylinder2507comprises openings shaped as X shaped slots2511that enable only the passing of air entering the cartridge (e.g. blocking powder cartridges from returning). In some embodiments, x-shaped slots act as a one way valve. In some embodiments, external cylinder2507is formed of an elastic material.FIGS. 25E and F show an X shaped slot2511in its closed configuration (E) and expanded star shaped configuration (F) in which air is allowed into the cartridge, blocking powder cartridges from returning (e.g. one way valve). In some embodiments, the air passes through one or more openings2503,2511in the cylinders and mixes with the powder, for example within lumen2513a. In some embodiments, prior to entry of gas such as air into the lumen of the cartridge, the powder particles remain at a bottom of lumen2513. In some embodiments, even when the pressurized air supply to the cartridge is reduced or stopped, the powder does not sink back to the bottom of the cartridge for example as shown inFIG. 25A.

In some embodiments, entrance2509to the cylinder is sealed by an external cylinder2500and/or by cover2507so that gas such as air which enters through entrance2509is forced to pass through slots2511to enter the internal cylinder2502, for example through holes2503. In some embodiments, fluid ejected through holes2505flows through lumen2513to a fusion tank within a handle connected to a nozzle.

Optionally, the fluid comprising the powder is then delivered to a fusion tank within the handle.

FIG. 25Dshows an exemplary configuration of a handle in which the air and powder supply, for example being mixed together in powder cartridge system2509, are delivered into the nozzle separately from liquid (for example delivered through mixer/tank2511). Optionally, by separating the liquid from the air and powder mixture, each component can be delivered separately into the nozzle, for example, mixing within the nozzle and/or root canal. For example, the nozzle may deliver only air and powder into the canal, and/or deliver only liquid into the canal.

In some embodiments, tube2510may be used for delivery of air, liquid, and/or powder and/or irrigation fluid and/or disinfection solution.

In some embodiments, suction tube2512is used to extract fluid and/or debris (e.g. from the root canal).

Alternatively, in some embodiments, suction tube2512in the handle may be used for discharge (e.g. of gas, liquid, and/or powder) instead of suction.

In some embodiments, the handle may be used with different types of nozzles, such as, for example, described herein.

In some embodiments, each of pipes2531,2533,2535,2537deliver one or more of gas (e.g. air) and/or fluid and/or powder and/or disinfection solution and/or irrigation liquid.

FIGS. 26 and 27are schematic diagrams of exemplary system for treating a root canal, according to some embodiments of the invention.FIG. 26, for example, includes the system described inFIG. 8above, further including a fluid mixer, a disinfecting fluid tank connected to a pump, and a liquid filter. Optionally, liquid flows directly into the handle and nozzle. Alternatively, fluid is first passed through the fluid mixer.

In some embodiments, one or more liquid tubes connects between the liquid tank and the fluid mixer, and/or connects the liquid tank directly to the handle. In some embodiments, one or more air tubes connect between the air compressor to the powder mixer, and/or from the air compressor directly to the handle.

FIG. 27further includes a powder mixer, which mixes air and powder together for example before entering the handle. Optionally, one or more components of the system are activated through a control panel connected to a controller. In some embodiments, the components of the system are separately controllable and can be operated with or without other components (for example, the air pump may be operated independently of the fluid mixer).

FIG. 28, now made reference to, illustrates a nozzle2800comprising a turbine2801for imparting spin to a working fluid, according to some exemplary embodiments of the invention.

In some embodiments of the invention, there is provided a turbine2801, operable to impart momentum to flow exiting the nozzle aperture2802. The turbine design potentially allows transfer of energy from, for example, a pressurized gas supply, into a working fluid for cleaning and/or eroding of a root canal. In some embodiments, combining of turbine-driven and direct pressure-driven working fluid sources that meet in flow coming from2827into the lumen between the internal cone and external cone. Fusion of these flows potentially allows control to achieve a broadened range of exit jet and angles properties at the meeting between two flows2806.

In some embodiments, the turbine2801is activated by a flow of air, for example from inlet2804. Optionally, the flow of air enters through pipe2804configured within the handle. In some embodiments, the turbine is operable at one or more frequencies in a range of, for example: 2000-10,000 RPM, 5,000-25,000 RPM, 10,000-100,000 RPM, 10,000-400,000 RPM, 2000-400,000 RPM, or another range of rotational frequencies. In some embodiments, the pressure of air for driving the turbine is, for example: 10-20 PSI, 15-25 PSI, 10-30 PSI, 30-40 PSI, 30-60 PSI, or another range of driving pressures.

In some embodiments, turbine2801is operable to rotate pipe2807, which extends from a fluid inlet in the region of the turbine toward a distal end of the nozzle2800. In some embodiments, the turbine is operable to spin fluid that enters pipe2807, provided, for example, through pipe2805. Additionally or alternatively, fluid (provided, for example, from pipe2803) flows into lumen2825, and optionally passes through the slanted tube2827. In some embodiments, turbine2801causes an axial rotation of pipe2807, thereby spinning the fluid contained within. Optionally, the fluid exiting pipe2807has a helical flow profile. In some embodiments, spinning of the fluid within pipe2807affects a velocity and/or pressure of the fluid.

In some embodiments of the invention, pipe2807is provided with a helically formed lumen. A helically formed lumen provides a potential advantage for imparting directionality to fluid therein, by urging the fluid along the length and/or around the axis of pipe2807.

In some embodiments, turbine2801is coupled to motor2809, for being movable, for example, in the proximal and/or distal directions. In some embodiments, motor2809comprises a stepper motor. Optionally, coupling is through threaded element2811and/or rods2813. In some embodiments, motor2809comprises, additionally or alternatively, a driving means for moving internal cone2815in distal and proximal directions, optionally coupled through threaded element2811and/or for moving pipe2807in distal and proximal directions. Optionally, movement of internal cone2815and pipe2807in distal and proximal directions is independent for example, at different speeds and/or directions and/or frequencies e.g. as internal cone2815moves distally, pipe2807moves proximally. Alternatively, movement of internal cone2815and pipe2807is synchronized.

In some embodiments, movement of the internal cone and/or pipe is manual, e.g. where a user manually moves one or more part (e.g. by pressing a button mechanism optionally including a spring) to move the internal cone and/or pipe.

The cross section along line A-A shows rods2813. The cross section along lines C-C, for example, shows the internal cone2815, external cone2817, a lumen2819within the internal cone2815, pipe2807, a lumen2823of pipe2807through which fluid passes, and a suction cone2821positioned externally to both cones.

In some embodiments, the turbine is sealed by a sealing element2830, for example preventing fluid and/or air to pass in the proximal direction.

In an example of nozzle operation, fluid injected into pipe2803finds its way to region2806from tube2807, having acquired during its transit a pattern of flow which may be, for example, helical. Some control of flow pattern properties is optionally exercised by relative motion of inner cone2815relative to external cone2817, driven, for example, by stepper motor2809. In some embodiments, fluid injected into pipe2805finds it way, optionally simultaneously, through pipe2807, also reaching region2806. In some embodiments, the two fluid flows are combinable at region2806. In some embodiments, advancing or retracting pipe2807potentially allows control of parameters of fluid flow patterns exiting from aperture2802. Parameters adjustable potentially include, for example, the cone exit angle and/or the vertical and/or horizontal velocity components of exiting fluid. In some embodiments, fluid of different compositions is supplied to pipes2805and2803(or one of pipes2805,2803), and control of mixing is provided, for example, by positioning of pipe2807and inner cone2815.

It should be noted that the turbine and its related features such as the frame connecting to the motor can be assembled in nozzles of various configurations, such as nozzles having a geometry other than conical (for example, cylindrical).

FIG. 29, now made reference to, illustrates a nozzle comprising a turbine2901, according to some exemplary embodiments of the invention.

In some embodiments of the invention, turbine2901is driven by pressurized air, for example as described in connection withFIG. 28, hereinabove.

In some embodiments the nozzle does not comprise an internal and external cone, but rather one solid cone2903which is optionally positioned within a suction cone2905. In this figure, fluid entering the nozzle—for example, through pipe2907in the handle flows into pipe2909which is coupled to turbine2901, for example as described hereinabove.

In some embodiments corresponding toFIG. 29, fluid passes to the nozzle tip only through pipe2909. In some embodiments, pipe2909is axially rotated by turbine2901, causing fluid passing through it to spin. Potentially, the spun fluid within pipe2909exits nozzle tip2902at an angle imparted by its momentum. In some embodiments, stepper motor2911is coupled to turbine2901and/or to pipe2909for moving one or both of them in the proximal and/or distal directions. The cross section along line C-C shows cone2903, pipe2909, a lumen2913formed within pipe2909through which fluid passes, and the external suction cone2905.

In some embodiments, the turbine is operable at one or more frequencies in a range of, for example: 2,000-10,000 RPM, 5,000-25,000 RPM, 10,000-100,000 RPM, 10,000-400,000 RPM, 2,000-400,000 RPM, or another larger or smaller range of rotational frequencies. In some embodiments, the pressure of air for driving the turbine is, for example: 10-20 PSI, 15-25 PSI, 10-30 PSI, 30-40 PSI, 30-60 PSI, or another larger or smaller range of driving pressures.

In some embodiments, pipe2909is smooth-bored. Potentially, spinning motion is imparted to fluid passing therethrough by viscous forces acting between the fluid and the lumenal wall of pipe2909. Advancing and retraction of pipe2909relative to nozzle aperture2902potentially regulates the characteristics and/or parameters of flow exiting aperture2902, for example, by changing its pathway through the nozzle chamber between a distal end of pipe2909and aperture2902.

In some embodiments, the adjustment up and down of motor2911(e.g. moving pipe2909) increases or decreases the vertical velocity and pressure in the space under the exit of the distal end of tube2907in the conical lumen.

FIG. 30, now made reference to, illustrates a nozzle comprising a turbine3001coupled to an internal cone3003for rotating the cone around its axis, according to some exemplary embodiments of the invention.FIG. 30is an example of using a flow to rotate a flow modifying element.

In some embodiments, the internal cone3003is formed from a single solid piece comprising inner channels3005through which the fluid flows. In some embodiments, fluid enters the nozzle through pipe3007within the handle. In some embodiments, turbine3001rotates cone3003fast enough so that a centripetal force causes the fluid to flow along the walls of channels3005and/or causes fluid within the channels to spin and/or rotate. In some embodiments of the invention, momentum, potentially including angular momentum, is transferred from the motion of the turbine to the working fluid passing through cone3003before it is ejected from the nozzle. In some embodiments, fluid ejected from the nozzle is spinning/rotating/has helical flow.

Potentially, fluid exiting the nozzle does so at an angle which is broadened by the tangential component of its momentum at the exit aperture of the nozzle.

Cross section A-A shows rotating cone3003, channels3005, and an external cone3007. The cross section also shows a lumen3009between the rotating cone3003and external cone3007.

It should be noted that fluid exiting the distal aperture of cone3003is potentially in direct association with fluid external to the nozzle, the distal aperture being isolated from the surrounding tissue only by a relatively short sheathing length of the nozzle's outer wall. In some embodiments, this potentially improves the efficiency of energy transfer from the nozzle interior to the exteriorly acting working fluid.

FIGS. 31A-31B, now made reference to, show a conical nozzle in which only the narrowing portion3101of internal cone3103is movable with respect to external cone3105, according to some exemplary embodiments of the invention.

In some embodiments, inner walls of a (optionally needle-like) nozzle tip have a helical shape and/or grooves.

In some embodiments, different geometry of a nozzle tip, for example shape and/or diameter affect beam and/or angle jet axial velocity.

In some embodiments, geometry of the cross section of the nozzle tip has different geometries which affect fluid flow parameters.

In some embodiments of the invention, portion3101is connected to one or more rods3107which are distally/proximally positionable by stepper motor3109. Optionally, rods3107are coupled to a threaded element3111. InFIG. 31A, narrowing portion3101is shown lifted in the proximal direction, while inFIG. 31B, narrowing portion3101is shown advanced in the distal direction. Optionally, movement of the narrowing portion3101modifies a lumen between the cones, as described hereinabove.

In some embodiments, movement of the internal cone and/or pipe is manual, e.g. where a user manually moves one or more part (e.g. by pressing a button mechanism optionally including a spring) to move the internal cone and/or pipe.

In some embodiments, there is, for example, a ratchet or rotation of a rotating element via thread sets in different locations.

FIGS. 32-37show various modes of operation of a system in accordance with some embodiments of the invention. Such modes are optionally achieved by varying parameters of the system such as one or more of pulse time, duty cycle, pulse rate, air/liquid ratio, and/or added powder.

FIGS. 32-34show the operation of a system, in accordance with some embodiments of the invention, where a plurality of jets4301(optionally a part of, or in the form of, a continuous cone of fluid or other beam shape) are discharged by the nozzle. As shown in a first condition inFIG. 32, a root canal4315has fluid up to a level4421, in parameter conditions where a fluid level is formed. Jets4301hit a wall4303of root canal4315and form a cyclone4313. In some embodiments, the cyclone comprises an aerosol combination of fluid droplet and gas.

In a second condition shown inFIG. 33, after a brief time (which may be, for example, 10-20 msec, 10-50 msec, 25-100 msec, 50-200 msec, or another larger or smaller interval of time), an evolution of conditions has occurred. Potentially, a density of fluid has increased above fluid level4421, as fluid is injected into the root canal. In some embodiments, gas which initially exited the nozzle has been displaced by heavier fluid exiting the nozzle during the interval of evolution. In some embodiments, fluid which initially exited the nozzle has lost a portion of its velocity to interactions with the environment of the root canal. Potentially, less energetic fluid is displaced toward the center of the developing cyclone as new fluid is injected. A counterflow upwards potentially also begins as additional fluid is introduced from above with sufficient axial velocity to force its way downward. In some embodiments, the energetic fluid also begins to set up turbulent zones, which potentially change their position, velocity, and/or size over time.

In a third condition, shown inFIG. 34, a fully developed cyclone has arisen. In some embodiments and conditions, the fully developed cyclone arises after brief interval from the situation shown inFIG. 33. The interval is, for example, 10-20 msec, 10-50 msec, 25-100 msec, 50-200 msec, or another larger or smaller interval of time. In some embodiments of the invention, the cyclone develops to reach an apex4319of the root canal.

In some embodiments, the cyclone comprises fluid that was previously below the fluid level4421which has received energy transferred to from the injected fluid. Additionally or alternatively, the fluid injected form the nozzle carries sufficient energy to force its way down to the tip. In some embodiments of the invention and conditions, a counterflow develops such that fluid which reaches the apex4319is forced upward again in a counterflow by new fluid following behind it. Optionally, this flow occurs in addition to or instead of rotation caused by fluid traveling along the wall. In some cases, fluid below the fluid level4421are turbulent and include significant flow vectors other than parallel to and along the wall of the root canal4315. Optionally, the turbulence helps remove debris, dentine, and/or soft tissues from the wall, tubules, and/or out of the canal. In some embodiments, a fluid level can be achieved, theoretically, even when the tooth is turned upside down.

It should be understood that the interactions of air and water (gas and fluid) in the root canal potentially create a condition in which inertial forces strongly dominate viscous forces (a high Reynolds number). As new air/water mixture is injected into the root canal, energetic and potentially turbulent flow is carried with relatively great freedom throughout the region being irrigated, as losses due to viscosity become relatively negligible. It should be understood that the boundaries of various relative fractions of gas and fluid at various depths of the root canal are potentially continuous and/or indistinct during active irrigation, as turbulence and other activity cause fluctuations in flow. In some embodiments, the boundary deeper than which (reaching into the root canal) the total volume of fluid and air in the channel is at least 50% fluid is, for example, about 3-4 mm, about 4-5 mm, about 4-8 mm, about 6-9 mm, or another larger or smaller depth. The conditions of initial gas/fluid mixing associated with these depths are, for example, selected from among those described in connection with Table 1, hereinabove.

FIGS. 35-37show the operation of a system, in accordance with some embodiments of the invention, where fluid is delivered through a needle-like cylinder5401. Optionally, cylinder5401is axially rotated within the nozzle, for example by a turbine as described above. Optionally, a distal end of the cylinder is positioned above root canal entrance5425. Alternatively, a distal end of cylinder5401is entered, at least partially, into the root canal, as inFIGS. 35-37. Optionally, an exit aperture of cylinder5401is leveled with a level of fluid5421within the canal. Alternatively, the exit aperture of cylinder5401is advanced into the fluid within the canal, for example 0.1 mm, 0.5 mm, 1 mm, 2 mm, 4 mm. or intermediate, larger or smaller distances.

In some embodiments, the rotating cylinder5401directly couples to fluid within the canal to rotate it (for example, as inFIG. 36). In some embodiments, the helical flow exiting cylinder5401induces a helical, rotational and/or turbulent flow within the canal, for example when the hitting fluid that accumulated within the canal (FIG. 35), and additionally or alternatively by replacement of the accumulated fluid with fluid and/or air that has been energetically injected into the root canal. In some embodiments, the rotating cylinder forms a cone shaped beam of fluid exiting the cylinder. In some embodiments, the flow of the cone shaped beam has an angular component (i.e. not only a vertical component) so that the conical beam is effectively formed of a plurality of angled jets.

In some embodiments, flows, counterflows, turbulence, and other features of the motion of fluid described hereinabove in relation, for example, toFIGS. 32-34, are induced. In particular, helical and/or turbulent flow potentially propagates all the way to the apex5319of the root canal. Potentially, full penetration of the root canal is assisted by high energy and relatively low viscosity of an air/water mix ejected from the tip of the nozzle.

FIG. 38shows various configurations of needle-like tubes which can be assembled onto a nozzle, for example assembled on a distal exit aperture of the nozzle. The various configurations are suitable for use with root canals having different anatomical structures. The various configurations may comprise different lengths, different profiles of exit apertures, different diameters. In some embodiments, a proximal end of the needle like tube is coupled to a distal end of a nozzle. Optionally, the needle like tube is attachable by a threaded connection. In some embodiments, a nozzle is structured such as to connect, such as by fastening means (a screw, clasp or other) by adhesive means, and/or by a structural geometrical connection to one or more types of needle-like tubes. In some embodiments, the needle like tubes form different types of beams and flow patterns. Optionally, a needle like tube is selected to affect the velocity of the flow, for example between the angular velocity of the fluid circulating within the nozzle and the tangential velocity of the flow exiting the nozzle. In some embodiments, the distal aperture of the needle like tube comprises a circular profile, an elliptical profile, an oval profile, a beveled form, a trapezoid profile, a triangular profile or any other profile and/or geometry.

FIG. 39Ais a simplified schematic cross sectional view of a nozzle3901lacking an internal cone, according to some embodiments of the invention. In some embodiments, one or more angled jet (e.g. a jet at an angle which does not intersect a vertical axis of the nozzle) is discharged from a cone lacking an internal cone. In some embodiments, fluid discharged from a jet without an internal cone intensifies or causes rotation of fluid within an at least partially filled root canal.

In some embodiments, fluid flows through a nozzle lumen lacking an inner cone with a helical and/or rotating path and/or the fluid flows in contact with lumen walls.

In some embodiments, a pipe3903(optionally, in some embodiments, more than one pipe) carrying material (e.g. fluid including one or more of liquid, air, abrasive powder, disinfection component/s) extends into nozzle lumen3907and pipe3903includes a pipe outlet3909which is proximal to a portion nozzle lumen walls3916. In some embodiments, the pipe and/or pipe outlet is angled and/or positioned and/or shaped such that a flow3911(e.g. jet) of fluid from pipe3903impacting a portion of nozzle lumen walls3916flows in a radial and/or centrifugal and/or helical and/or spiral manner, e.g. spiraling downwards through nozzle lumen3907. In some embodiments, an angle of the flow (e.g.) exiting pipe3907is at an angle which does not intersect a vertical axis of the nozzle.

In some embodiments, flow speed and/or pressure and/or composition contribute to helical flow of fluid within the nozzle and/or characteristics and/or parameters of jet/s discharged from the nozzle.

In some embodiments, pipe3903is runs through a handle3904attached to nozzle3901.

In some embodiments, flow3911substantially remains in contact with the nozzle lumen wall (e.g. flowing within 5 mm of, or within 2 mm of, or within 1 mm of, or within 0.5 mm of, or within 0.1 mm of or within 0.01 mm, of the walls or smaller, or larger, or intermediate measurements. In some embodiments, flow3911exits nozzle3901through a nozzle outlet (also termed nozzle exit aperture)3913.

Optionally, nozzle3901includes a narrow, needle like tip3915, e.g. with a diameter of, for example, less than 5 mm, or less than 2 mm, or less than 1 mm, or less than 0.5 mm, or less than 0.2 mm, or less than 0.1 mm, or less than 0.05 mm, or less than 0.01 mm. Alternatively, in some embodiments, nozzle tip3915is larger e.g. with a diameter of more than 0.5 mm, or more than 1 mm, or more than 2 mm, or more than 5 mm, or more than 10 mm.

Optionally, at least a portion of an inner surface of nozzle lumen walls3916is textured (e.g. grooved), potentially assisting and/or enabling helical flow of the fluid. In some embodiments, grooves are helical and/or spiral downward towards nozzle outlet3913. In some embodiments, grooves are other than helical, for example in some embodiments, grooves form a double helix, in some embodiments grooves form two opposing helixes. Optionally, in some embodiments, nozzle outlet3913is textured (e.g. grooved) potentially assisting and/or enabling helical flow of the fluid as it exits through outlet3913.

In some embodiments, helical and/or spinning and/or rotating of the flow within the nozzle results in emission from the nozzle outlet of angled fluid jet/s.

Optionally, nozzle3901includes one or more inlet through which material is removed from the tooth, e.g. by suction. In an exemplary embodiment, nozzle3901includes a suction cone3917which, in some embodiments, is a structure (optionally cone-shaped) at least partially surrounding the nozzle lumen walls where there is a lumen3921(optionally cone shaped) between the nozzle lumen walls3916and suction cone3917. In some embodiments, lumen3921connects to an extraction pipe3923within handle3904and suction of material through inlets3919a,3919bis applied by pressure reduction at extraction pipe3923(e.g. using a pump connected to extraction pipe3923).

FIG. 39Bis a simplified schematic cross sectional view of a nozzle3901lacking an internal cone, according to some embodiments of the invention.FIG. 39Bshows a cross section perpendicular to the cross section illustrated inFIG. 39Ataken along the line A-A illustrated onFIG. 39A. In some embodiments, as illustrated inFIG. 39B, the portion of pipe3903which extends into nozzle lumen3911is curved and/or bent, for example, bending so that the pipe is in close proximity to nozzle lumen walls3916.

In some embodiments, one or more inlet into a nozzle lumen moves, for example, rotates.FIG. 40Ais a simplified schematic cross sectional view of a nozzle4001including a rotating inlet element4005, according to some embodiments of the invention.

In some embodiments, fluid is inserted into a nozzle through a rotating inlet element4005. In some embodiments, rotating inlet element4005includes one or more exit aperture (e.g. two exit apertures4023) through which fluid is inserted into a nozzle lumen4007. In some embodiments, each exit aperture4023is located on a rotating inlet element arm4025. In some embodiments, fluid (e.g. including one or more of liquid, gas (e.g. air), abrasive powder, disinfection component/s, and flushing fluid) is supplied to rotating inlet element4005through a pipe4003connected to rotating inlet element4005. In some embodiments, pipe4003runs through a handle4037connected to the nozzle4001.

In some embodiments rotating inlet element4005is disposed within a nozzle lumen4007where the lumen is a space between an inner cone4019and an outer cone including nozzle lumen walls4021. In some embodiments, nozzle4001includes a nozzle tip4041through which fluid is discharged. Alternatively, the nozzle does not include an inner lumen and the rotating element is disposed inside a nozzle lumen defined by nozzle lumen walls4021.

In some embodiments, rotation and/or movement of rotating element4005and/or the shape of the conical lumen causes the fluid to flow in a rotating and/or helical downwards motion.

In some embodiments, rotating element4005and fluid flow within the nozzle is not exposed to the atmosphere, a potential benefit being that fluid flowing through the nozzle is not exposed to the atmosphere, for example, preventing degradation of the fluid and/or component/s of the fluid e.g. by exposure to atmospheric contaminants such as dirt, bacteria, e.g. by exposure of reactive component/s to atmospheric oxygen.

In some embodiments of the invention, momentum, potentially including angular momentum, is transferred from the motion of the rotating element4005to the working fluid passing through lumen4007before it is ejected from nozzle. In some embodiments, fluid ejected from the nozzle is spinning/rotating/has helical flow.

Potentially, fluid exiting the nozzle does so at an angle which is broadened by the tangential component of its momentum at the exit aperture of the nozzle.

Optionally, in some embodiments, nozzle4001includes one or more additional pipe, e.g. a second pipe4003athrough which air flows into an air turbine4043. In some embodiments, rotating inlet element4005is rotated by air turbine4043. Alternatively, rotating inlet element4005is rotated by mechanical and/or electrical means e.g. by a stepper motor connected to the rotating inlet element.

Optionally, in some embodiments, a second material is inserted into lumen4007. In some embodiments, the second material is air and/or pressurized gas (e.g. pressurized air) which optionally pushes fluid towards a nozzle outlet4015. Optionally, movement and/or rotation of rotating inlet element4005mixes the second material with the fluid inserted through pipe4003.

Optionally, in some embodiments, an additional pipe, a third pipe4003binserts material and/or fluid into a second conical lumen4029. In some embodiments, third pipe discharges disinfecting fluid and/or flushing fluid.

Optionally, nozzle4001includes one or more inlet through which material is removed from the tooth, e.g. by suction. In an exemplary embodiment, nozzle4001includes a suction cone4017which, in some embodiments, is a structure (optionally cone-shaped) at least partially surrounding the nozzle lumen walls4021where there is a lumen4031between nozzle lumen walls4021and suction cone4017through which material is extracted. In some embodiments, lumen4031connects to an extraction pipe4033within handle4037and suction of material is by pressure reduction at extraction pipe4033(e.g. using a pump connected to extraction pipe4033).

In some embodiments, suction of material from the root canal reduces pressure in a root canal apex and/or an apical area (portion of the root canal proximal to the apex).

In some embodiments, movement of nozzle parts, for example, movement of the internal cone, is manual e.g. where a user manually moves one or more part (e.g. by pressing a button).

In some embodiments, suction can be used to control an extent of rotation and/or fluid within a root canal. For example, in some embodiments, increased suction reduces a length and/or strength (e.g. velocity of flow) of a water column within the root canal.

FIGS. 40B-40Care simplified schematic cross sectional views of a nozzle including a rotating inlet element4005, according to some embodiments of the invention.FIG. 40BandFIG. 40Cshow cross sections perpendicular to the cross section illustrated inFIG. 40Ataken along the line A-A and line B-B illustrated onFIG. 40Arespectively. In some embodiments, as illustrated inFIG. 40C, lumen4007is optionally divided by one or more divider4035for dividing the flow through lumen4007. Optionally, in some embodiments, dividers are located along the length of lumen4007.

In some embodiments, a rotating element mixes and/or agitates fluid flowing through a nozzle lumen.FIG. 41is a simplified schematic cross section of a nozzle4101including a rotating element4105, according to some embodiments of the invention.

In some embodiments, rotating element4105rotates4141around a rotating element long axis. In some embodiments, rotating element4105includes one or more protruding element, e.g. blades4119. In some embodiments, blades have a flattened shape, for example, where a thickness of the blade is less than half, or a quarter, or a tenth or smaller, larger or intermediate proportions, of a length and/or a depth of the blade. In some embodiments, the blades provide a large surface area of contact between the rotating element and fluid flowing through the nozzle, potentially increasing energy and/or momentum transfer between the rotating element and the fluid.

In some embodiments, the blade/s are shaped such that the blades push and/or pump the fluid through the nozzle toward a nozzle exit aperture4121, for example, the rotating element acts as an impellor. For example, in some embodiments, one or more blade is at an angle to a vertical axis of the nozzle where a length-depth plane of the blade is at an angle to the vertical axis of the nozzle e.g. by at least 2 degrees, or 10 degrees, or 25 degrees, or 45 degrees, or 90 degrees, or smaller, or larger, or intermediate angles.

In some embodiments, fluid (e.g. including one or more of liquid, air, abrasive powder, disinfection component/s) is inserted into the lumen through a fluid pipe4103.

In some embodiments, rotating element is rotated by an air turbine4123where air is supplied to the turbine through a second pipe4103a.

In some embodiments, a second material, for example, air and/or another gas is inserted into the lumen through pipe4103. In some embodiments, pressurized material inserted through pipe4103(e.g. pressurized air) pushes fluid inside lumen4143towards outlet4121and/or rotating element blades4119.

In some embodiments, movement of rotating element4105mixes material inserted into nozzle lumen4143. For example, mixing fluid inserted through pipe4103.

For example, in some embodiments, materials are inserted separately, e.g. through pipe4103where different materials are inserted in alternative pulses, e.g. through pipe4103and optionally through additional pipe/s.

In some embodiments, helical and/or spinning and/or rotating of the flow within the nozzle results in emission from the nozzle outlet of angled fluid jet/s.

A potential benefit of mixing materials within a nozzle lumen is that the materials are not exposed to the atmosphere, for example, preventing degradation of the materials e.g. by exposure to atmospheric contaminants such as dirt, bacteria, e.g. by exposure of reactive materials to atmospheric oxygen.

Optionally, nozzle4101includes one or more inlet through which material is removed from the tooth, e.g. by suction. In an exemplary embodiment, nozzle4101includes a suction cone4117which, in some embodiments, is a structure (optionally cone-shaped) at least partially surrounding the nozzle lumen walls4121where there is a lumen4131between nozzle lumen walls4121and suction cone4117through which material is extracted. In some embodiments, lumen4131connects to an extraction pipe4133within handle4125and suction of material is by pressure reduction at extraction pipe4133(e.g. using a pump connected to extraction pipe4133).

Optionally, rotating element4105includes a hollow portion through which material is inserted into lumen4143.

Optionally, nozzle4101does not include an internal cone.

In some embodiments, nozzle4101includes a nozzle tip4145through which fluid is discharged.

In some embodiments the pressure in apical area and apex is controlled (e.g. kept low), for example, by spreading or dividing the flow of fluid. In some embodiments, fluid is discharged into a root canal such that the fluid does not directly impact the apex and/or apical area. For example, in some embodiments, fluid is discharged such that fluid hits a wall of the root canal above (coronal) an apical area of the root canal. For example, in some embodiments, fluid is discharged at an angle at least 10 degrees, or at least 30 degrees, or at least 90 degrees from an angle of a straight line connecting a discharge point of the fluid from the nozzle and the apex.

A potential benefit of helical flow of fluid within a root canal is that fluid is less likely to directly impact the apex and/or apical region, for example, in a time period at a beginning of a treatment and/or at a beginning of discharging of fluid (e.g. the first 0.1 s, 0.5 s, or 1 s, or 5 s or higher, lower or intermediate times) into a root canal before the root canal fills with fluid. In some embodiments, a root canal is filled with fluid e.g. manually and/or through the nozzle (e.g. at a low speed and/or pressure and/or flow rate) potentially protecting the apex.

In some embodiments, a needle tip4241including a needle tip lumen which increases in cross sectional area distally towards a nozzle aperture4243. The liquid exiting from the nozzle through tip4241exits with a wide angle of, for example, 20-70 degrees, or lower, or higher, or intermediate angles, flowing and filling the root canal e.g. from the apex of the canal upward (coronal), with wide angle of flow, meaning that the pressure of the flow is divided along the wall surface e.g. as a non-direct flow.

In some embodiments, pulsed suction and/or discharging reduces pressure of fluid flow at the apex and/or apical area e.g. fluid is extracted before it reaches the apex and/or apical area. In some embodiments, for example, due to the narrow space in the apical area pressure reduction from suction is more rapid than in the remainder of the root canal (e.g. at 1.5× the rate, or at double the rate, or at triple the rate).

FIG. 42Ais a simplified schematic cross sectional view of a nozzle4201treating a root canal4203, controlling apical parameters, according to some embodiments of the invention.FIG. 42Bis an enlarged view of a portion ofFIG. 42A.

In some embodiments, flow of fluid within a root canal is controlled and/or balanced by control of insertion of fluid into the root canal and suction of material from the root canal. In some embodiments, depth of penetration (e.g. to the apex, e.g. not past the apex in the apical direction) of flow into the root canal is controlled. In some embodiments, pressure of flow and/or amount of abrasion at an apex of a root canal is controlled.

In some embodiments, pressure inside a root canal is controlled and/or balanced, for example, by controlling insertion of fluid into the root canal (increasing pressure in the canal) and suction of material from a root canal (decreasing pressure in the canal). In some embodiments, rhythms and/or durations of pulses of insertion (jetting) and/or suction control pressure in the canal e.g. with suction and jetting independently and/or simultaneously, e.g. with suction and/or jetting periodically.

A potential benefit of controlling pressure within the canal is the ability to control pressure at the root canal apex e.g. reducing pressure at the apex, e.g. potentially preventing rupture of the tooth e.g. at the root canal apex.

In some embodiments, suction and/or insertion of fluid is controlled to reduce pressure inside the root canal e.g. at and/or including pressure at the apex of the root canal. A potential benefit of reduced pressure within the root canal is a reduction in risk of breaking and/or rupturing the root canal and/or tooth.

In some embodiments, the root canal is sealed such that material can only enter or exit the root canal through a nozzle (e.g. the root canal is sealed at a coronal opening of the root canal). In some embodiments, control of pressure within the canal is enhanced by sealing of the root canal. In some embodiments, sealing of the root canal enables the nozzle to apply higher and/or lower pressures to the root canal.

In some embodiments, a nozzle4201and a sealing element4207are placed at an entrance to a root canal4203, sealing the root canal, for example, only allowing movement of material in and out of the root canal through nozzle4201(e.g. only allowing movement of material out of the root canal through a suction cone4217).

In some embodiments, sealing element4207surrounds the nozzle, for example, is ring-shaped. In an exemplary embodiment, the sealing element includes rubber e.g. silicone rubber. In some embodiments, sealing element4207is a separate component. In some embodiments, sealing element is coupled to and/or forms part of the nozzle.

In some embodiments, nozzle4201introduces fluid (e.g. fluid jet/s optionally including air and/or abrasive material) into the root canal4203, for example, to clean the root canal. In some embodiments, nozzle4201includes a suction cone4217which extracts material through channel4235, where suction cone inlets4239are apical of sealing element4207. In some embodiments, a cross sectional area of a nozzle tip4241enlarges distally.

In some embodiments, the jet does not flow straight downwards towards the apex of the root canal e.g. the jet flows along the canal walls cleaning the walls. In some embodiments, one or more jet meets the root canal wall at an angle of 20-45 degrees, or 30-45 degrees to the root canal wall. Jet flow along the wall potentially reduces pressure at the apex, for example, as pressure of the jet is spread over a surface of the root canal wall.

FIG. 42Cis a simplified schematic cross sectional view of a nozzle surrounded by a sealing element4207, according to some embodiments of the invention.FIG. 42Cshows a cross section perpendicular to the cross section illustrated inFIG. 42Ataken along the line A-A illustrated onFIG. 42A. Visible inFIG. 42Cis sealing element4207surrounding the nozzle. Also visible is a nozzle inner cone4245.

Optionally, nozzle4201includes an internal cone with a lumen e.g. as illustrated inFIG. 31A.

In some embodiments, nozzle4201includes a pipe4231for supplying fluid to a nozzle lumen4237.

In some embodiments, a wide or fan-like beam of fluid is discharged. For example, a wide or fan-like beam is discharged from a nozzle tip where a tip lumen cross sectional areal (perpendicular to nozzle tip long axis) increases distally. For example, a wide or fan-like beam where the beam broadens as a distance between the beam and nozzle exit aperture increases e.g. at least doubles in cross sectional area (cross section perpendicular to nozzle vertical axis) at 0.01 mm, or 0.1 mm, or 0.5 mm. or 1 mm. or 1 mm. or 5 mm from the nozzle exit aperture.

In some embodiments, a wide and/or fan-like beam has lower pressure. Potentially reducing pressure at a root canal apex or apical area.

In some embodiments, the lumen walls and/or the internal cone include a hollow portion, for example, increasing a length of a path of fluid within the nozzle.

FIG. 43Ais a simplified schematic side view of a nozzle4301including an external cone4305with a hollow portion4303and an internal cone4311with a hollow portion4309, according to some embodiments of the invention.FIG. 43Bis a simplified schematic cross sectional view of a nozzle4301including external cone4305with a hollow portion and an internal cone4311with a hollow portion, according to some embodiments of the invention.FIG. 43Bshows a cross section perpendicular to the cross section illustrated inFIG. 43Btaken along the line A-A illustrated onFIG. 43A.

In some embodiments, external cone4305includes hollow walls and internal cone4311includes hollow walls: A first lumen4303is within external cone4305and a second lumen4309is within internal cone walls4311.

In some embodiments, internal cone4311is smaller than and located within a lumen within external cone, forming a third lumen4350in the space between the external cone and the internal cone. In some embodiments, internal cone4311includes a fourth lumen4315. In some embodiments, an additional internal cone4311ais located inside internal cone4311.

Referring now toFIG. 43B, In some embodiments, external cone and/or internal cone4311rotate, for example, to increase energy and/or momentum of discharged fluid from the nozzle (e.g. to enhance rotation of fluid within the root canal and/or enhance cleaning of the root canal). Optionally, external cone4305and internal cone4311rotate at different times and/or with different speeds and/or with different direction of rotation, for example, to increase mixing of the fluid from the internal and external cone when the flows meet.

In some embodiments, fluid is inserted into lumens4303,4309is supplied by pipes4303p,4309prespectively.

Referring now toFIG. 43B, fluid inserted into the hollow portion of the inner cone (lumen4309) flows radially and/or helically through the hollow portion of inner cone to the lumen between the inner cone and the additional inner cone (lumen4315). Fluid inserted into the hollow portion of the external cone (lumen4303) flows radially and/or helically through the hollow portion of external cone to the lumen between the external cone and the inner cone (lumen4305).

In some embodiments, flows emerging from lumens4350and4315merge and/or mix in a central lumen4345before being discharged.

In some embodiments, fluid is inserted into lumens4303,4309concurrently and/or in a pulse pattern e.g. where material is inserted into one or more lumen intermittently. In some embodiments, fluid inserted into lumens4303,4309combines and/or mixes adjacent to a nozzle tip4319.

Optionally, nozzle4301includes one or more lumen4317through which fluid is extracted.

Optionally, nozzle4301includes an additional cone4319external to external cone4305, and fluid from pipe4341(e.g. flushing and/or disinfecting fluid) is inserted into the tooth through a lumen4343between additional cone4319and external cone4305.

In some embodiments, fluid flows through one or more lumen with helical movement. In some embodiments, rotation of the cone/s and/or a shape of the lumen/s causes emission from the nozzle outlet of angled fluid jet/s and/or a flow with helical flow.

In some embodiments, a system for cleaning and/or abrading a root canal operates without an external compressor. In some embodiments, the system includes one or more pressurized container.

FIG. 44is a simplified schematic cross sectional view of a system including a supply apparatus4403connected to a nozzle4401, according some embodiments of the invention.

In some embodiments, a supply apparatus is disposable and/or includes one or more disposable part. In some embodiments, a supply apparatus including one or more chamber containing pressurized gas, is located within a handle connected to a nozzle, forming a hand held endodontic cleaning device. A potential benefit being high portability and/or maneuverability of the device and/or a cleaning device which operates without any other infrastructure (e.g. compressor and/or external power supply).

Alternatively, in some embodiments, a supply apparatus is not located in the handle, e.g. supply apparatus includes a standing box.

In an exemplary embodiment, supply apparatus4403includes a first chamber4405which holds pressurized gas and fluid4405a. Optionally, the chamber comprises a predefined amount of gas and fluid, for example suitable for performing 1, 3, 5, 10, 20, 50, 100 or another number of treatments. Upon opening first chamber4405, the pressurized gas forces dispensing of fluid from the chamber (operation e.g. similar to an aerosol canister). In some embodiments, the gas includes air and/or CO2.

In some embodiments, the chamber is opened by pressing a button4407which opens a valve4409between first chamber4405and a second chamber4411and opens a second valve4413. In some embodiment, button4407is connected to a rod4447which pushes element4449towards valve4409, opening valve4409. In some embodiments, second chamber is enclosed inside a housing4441. In some embodiments, pushing button4407compresses a spring4445. In some embodiments, spring4445returns button4407to an original position after the button is released.

In some embodiments, second chamber4411holds abrasive powder and optionally pressurized gas. Optionally, the chamber comprises a predefined amount of abrasive powder and/or fluid, for example suitable for performing 1, 3, 5, 10, 20, 50, 100 or another number of treatments. Gas and fluid flow from first chamber4405through second chamber4411, collecting and/or mixing (optionally, mixing uniformly) with abrasive material from second chamber4411. The fluid mixture of gas, fluid and abrasive material then travels through pipe4415to a handle4417connected to nozzle4401. Optionally, in some embodiments (e.g. so that the user can switch the flow on and off at a location near to the nozzle) flow through handle4417(e.g. passing through a pipe4453in handle4417) is upon activation of the handle, e.g. by sliding a switch4419on the handle to an on position. The fluid mixture then flows through the nozzle, passing through a nozzle tip4457, and is discharged through a nozzle exit aperture4459. In some embodiments, nozzle4401includes outer walls4455.

In some embodiments, pressure inside one or both chambers4405,4411is 100-120 PSI, or 50-200 PSI or higher, or lower or intermediate pressure ranges or values. In some embodiments, a starting pressure of the first chamber is sufficient to dispense all of the fluid within the first chamber. In some embodiments, as a chamber empties a chamber size is reduced (e.g. second chamber moves towards first chamber) so that a chamber internal pressure is maintained.

In some embodiments, a ratio of gas to fluid within first chamber4405is 75% air 25% fluid, or 50% fluid 20% air, or 90% air 60%, or lower, higher or intermediate ratios. In some embodiments, the fluid mixture dispensed from supply apparatus through pipe4415includes 3-5% abrasive material (e.g. abrasive powder).

In some embodiments, the supply apparatus is and/or includes a part (e.g. a chamber) which is designed for single use, for example the apparatus or part is disposed after a single treatment. Alternatively, the supply apparatus and/or a part of the supply apparatus contains sufficient materials for 1, or 2, or 3, or 4, or 5, or, 10, or 50, or 100 treatments, or lower, or higher, or intermediate numbers of treatments.

In some embodiments, the supply apparatus weighs 20 g-3 kg, or 50 g-1 kg, or 50 g-500 g, or 50 g-200 g, or lower, higher or intermediate weights. In some embodiments, the supply apparatus is light enough so that it can be maneuvered by a user e.g. with one hand.

Optionally, in some embodiments, one or more chamber is refilled when empty. In some embodiments, one or more chamber and/or the supply apparatus is changed when empty and/or between treatments and/or between patients. A potential advantage of a supply apparatus operating using pressurized gas is that the nozzle need not be connected to a compressor and/or electricity supply.

Optionally, in some embodiments, a supply apparatus includes less than or more than two chambers, each chamber including one or more of gas, fluid, abrasive powder, and disinfecting material.

In some embodiments, two or more flows of material mix within a lumen of a nozzle, e.g. before discharge of the mixed flow into a root canal. In some embodiments, flows which mix inside the lumen of the nozzle are supplied by a supply apparatus including more than one pressurized chamber.

FIG. 45is a simplified schematic cross sectional view of a supply apparatus4503supplying two separate flows to a nozzle4501, according to some embodiments of the invention.

In an exemplary embodiment, supply apparatus4503includes two chambers supplying two flows of material to the nozzle, for example, through two separate channels (e.g. pipes) which connect the chambers to the nozzle. In some embodiments, pressure within one or more chamber is 100-120 PSI, or 50-200 PSI or higher, or lower or intermediate pressure ranges or values.

In some embodiments, a first chamber4505contains pressurized gas (e.g. air) and a second chamber4507contains pressurized gas and fluid. In some embodiments, activating first chamber4505, for example by pressing on first button4509opens the chamber (e.g. by opening a first chamber valve4511) allowing flow of air from first chamber4505(optionally through a pipe4541) through valve4511into chamber4549, and then to exit chamber4549through an opening4547connected to first pipe4513.

In some embodiments, first button4509is attached to a rod4553and pushing the first button pushes element4545towards valve4511, opening the valve.

Flow then flows through a powder cartridge4573optionally located in a nozzle handle4570and passes to the nozzle4501. The powder and air mix with fluid in a lumen4501aof nozzle4501. Fluid in lumen4501aflows through nozzle, and through a nozzle tip4569before being discharged through nozzle exit aperture4567.

In some embodiments, pressing on a second button4517opens a second chamber valve4519, allowing flow of air and fluid from second chamber4507(optionally through a pipe4565) to flow into chamber4559and then to pass through opening4557connected to a second pipe4521, and then through a pipe4515in handle4570to the nozzle lumen mixing with the abrasive powder and air in the nozzle lumen. Optionally, one or more flow is controlled by an activation element (e.g. slide switch4523) on the handle. Optionally, one or more of the flows passes through a powder cartridge4573(optionally located in the handle), collecting and/or mixing with abrasive material which the flow then carries to the nozzle lumen.

In some embodiments, second button4517is attached to a rod4579and pushing second button4517pushes an element4561towards valve4519, opening the valve. In some embodiments, pipes4513and4521can be closed by valves4551and4577respectively. In some embodiments, the chambers include a housing4543.

In some embodiments, more than two flows emanating from more than one chamber mix within the nozzle where each chamber contains one or more of gas, fluid, abrasive powder, and disinfecting material.

Experimental Examples

An Experiment for Testing the Feasibility of an Apparatus and Method for Endodontic Treatment Using Angled Fluid Jets

The inventors conducted an experiment for testing the feasibility of a system which comprises an apparatus for cleaning, abrading, and/or disinfecting a root canal as described above.

Experimental Design

41 human teeth specimens were extracted from patients. The specimens included a group of molars having 2-4 root canals, and a group of incisors having a single root canal. In total, 182 root canals were tested in the experiment. Each tooth specimen had one or various types of root canals, as indicated below.

5 types of root canals were tested: a standard root canal (53 specimens), a curved root canal (40 specimens), a sharp curved root canal (32 specimens), a root canal with an enlarged opening at the apex, ranging between 2-3 mm, which was created naturally as a result of calcification (33 specimens), and specimens with an extremely narrow root canal (24).

11 teeth specimens having 2-3 root canals each were extremely narrow, having an entrance aperture with a diameter smaller than 0.5 mm.

Immediately after the extraction, the specimens were placed in a 10% bleach solution, containing 10% chlorine and 90% water, (other solutions may also be used), to prevent dehydration of the root canals.

The following procedure was performed for each specimen. At first, an access cavity was drilled through the crown of the tooth to enable access through the pulp chamber to the root canal. An entrance to the root canal was exposed, and the specimen was placed back in the bleach solution. The specimen was then removed from the solution, and placed in a rubber mold. At this stage, the specimen was imaged using a 320 slices CT imaging device. Optionally, other imaging devices may be used.

An apparatus and system for example as described inFIG. 8above were used for cleaning, abrading, and disinfecting each of the specimens. A nozzle of the apparatus was inserted through the pulp chamber and positioned such that an exit aperture of the nozzle was configured vertically above the entrance to a root canal, at an approximate distance of 1-3 mm.

The fluid used for the treatment of the root canals contained water, air, and glass powder (used as an abrasive powder). The pressures used were a water pressure of 80 PSI, and an air pressure of 80 PSI. The fluid passed through the pipeline of the system, for example through pipes in the handle of the apparatus, reaching the nozzle and exiting through the exit aperture in the form of angled fluid jets, as previously described.

Cleaning, abrading and disinfecting of the root canal of each specimen was achieved by the flow of fluid advancing along the root canal wall, removing organic substance such as nerve tissue, pulp tissue, and/or debris, as previously described.

The treatment duration for each of the specimens was determined according to parameters such as the existence of a narrowing portion, the existence of curvature, the length of the root canal, and/or other parameters or combinations of them. The treatment duration used in this experiment was 15 seconds (applied to 13 specimens), 30 seconds (applied to 15 specimens), and 45 seconds (applied to 13 specimens). Optionally, other durations may be used.

Imaging of each specimen using a 320 slices CT imaging device was performed again at the end of the process.

Each specimen was tested for apex penetration (referred to in this example as further widening of a natural, normal opening of the apex), grade of apex penetration (if occurred), penetration along the canal wall, and the thickness of the eroded layer.

To prove that the root canals of the specimen are clean, an electro-scan microscope image was acquired from each specimen, as will be further explained.

Data Analysis and Results

FIG. 16A-Bis a table of the experiment results. The table shows that in all tested root canals, the apex was not penetrated (i.e. an initial natural opening was not widened). The table also shows that in all tested root canals, the root canal wall was not penetrated as well. The thickness of the removed dentin layer ranged between 100-200 μm for all tested root canals.

FIG. 17shows an image of the dentin layer and dentinal tubules of one of the specimens, taken at the end of the experiment described above. This image was taken by an electro scan microscope, using a magnification of ×5000.

Before acquiring the image, the specimen was stored in the bleach solution. Once the specimen was removed from the solution, it was sliced along a longitudinal cross section, to expose the internal lumen of the root canal. This exemplary image shows that the dentin layer1701and the tubules1703shave been cleaned and cleared by the flow of fluid, and do not have a smear layer.

General

It is expected that during the life of a patent maturing from this application many relevant endodontic apparatuses will be developed and the scope of the term endodontic apparatuses is intended to include all such new technologies a priori.

The term “consisting of” means “including and limited to”.