Reference to related application

The present application ciaims priority to earlier PCT application N°PCT/IB2012/055753 filed on October 19, 2012 in the name of Produits Dentaires SA, the content of which is incorporated in its entirety by reference in the present application,

F ieid of I ve ntion and bac kg rou nd

The present invention relates to irrigation procedures in the dental field, more particularly to irrigation procedures into the root canal and under the gum with an irrigating cannula or an equivalent device.

Root canal irrigation p!ays a major role in the cleansing and disinfection of the root canal and is an integral part of the root canal preparation procedures.

The most frequently used trrigants are sodium hypochlorite solution (disinfectant, antibacterial agent) and ethylenediaminetetraacetic acid, widely abbreviated as EDTA solution (tissue-dissolving, removal of the smear layer, chelating agents),

Periodontai disinfection of the gums also plays a major role in the treatment of gingivitis (inflammation of the gums) or periodontitis (inflammation around the tooth), in such cases, an irrigation procedure below the gum line in inflammatory or infected formed space is recommended. The most frequently used irrigants are hydrogen peroxide or chlorhexidine.

Such irrigation usually takes place through a rinsing cannula (or a dental irrigating needle) connected to a fluid delivery system (e.g. a syringe). Examples of prior art devices are given in the following publications: WO 01/93773, US 2003/0013064, US 2009/0004621 , WO 2005/122943, WO 2007/140020, EP 1 712 201 and EP 0 290 011.

Summary of Invention

The prior art devices have the following disadvantages and problems:

- inadequate delivery rate of irrigant into the root canal or under the gum,

- risk of penetration of the irrigant beyond the apical foramen into peri-apical tissue (edema and hematoma usually occur as a consequence),

- incomplete cleansing of the walls (dentin and/or gum and/or bone) due to insufficient irrigation flow against the treated surface.

Accordingly, it is an aim of the present invention to improve the known devices and methods.

It is a further aim of the present invention to provide a simple system that is efficient, easy and safe to use.

Another aim is to provide a device that is cheap enough to be single use, that may be sterilized and that is universal (i.e. It may be used with different delivery systems).

These aims are reached by the device as defined in the claims.

In one embodiment, the invention concerns cannula for a dental irrigation spray system:, wherein said cannula comprises at least a closed tip at its distal end and at least a set of three radial orifices located near said tip of said cannula.

In one embodiment, the radial orifices of the first set are clearly separated from each other to spread all around at 360° and are on the same plane or a different one.

In one embodiment the cannula comprises at least a second set of radial orifices. In one embodiment the radiai orifices of the second set are clearly separated from each other to spread all around at 360° and are on the same plane or a different one.

!n one embodiment the radial orifices of the first set have the same size than the radial orifices of the second set or a different size.

!n one embodiment the tip has a spherical shape or another shape for occlusion of the treated zone.

In one embodiment the cannula comprises a channel connected to said radial orifices for delivery of a product.

In one embodiment the cannula is flexible.

In one embodiment the cannula has a conical shape.

In one embodiment the cannula is connectab!e on a spray recipient or a bottle. in one embodiment the cannuia is combined with connection system such as a Luer Lock connector.

The cannula is preferably made from a thermoplastic material, such as PE or PP. in one embodiment the invention concerns an irrigating system comprising at least a cannula as defined herein.

In one embodiment the irrigating system comprises a spray can on which the cannula is connected. Preferably, the spray uses the "Bag on Valve" (BOV) technology,

!n one embodiment the invention concerns an irrigating procedure using a cannuia as defined herein or an irrigating system as defined herein. Accordingly, in one embodiment the present invention defines a cannula suitable for the irrigation process described herein with improved properties over the prior art devices and also a spray system using said cannula.

The present invention will be better understood from the following description of detailed embodiments and from the figures that show

Figure 1A illustrates detail B of figure 1 B in cut view;

Figure I B illustrates a cut view of an embodiment of the cannula according to the invention;

Figure 1 C illustrates an embodiment of the cannula of the invention in perspective view;

Figure 1 D illustrates an embodiment of the cannula of the invention in cut view along line CC of figure 1A;

Figure 2 illustrates another embodiment of the invention in a perspective view; Figure 3 illustrates another embodiment of the invention in a perspective view; Figure 4 illustrates another embodiment of the invention in a perspective view; Figure 5 illustrates another embodiment of the invention in a perspective view; Figure 6 illustrates a general perspective view of an embodiment of the invention; Figures 7 and 8 illustrate possible exemplary uses of the present invention. Detailed description of the invention in a first embodiment illustrated schematically in figures 1A to 1 D, a cannula 1 according to the invention comprises the following aspects and features.

The cannula 1 has preferably an elongated shape with a closed tip 2 at its distal end and a plurality of radial orifices 3 (see figure I D). The cannula 1 may be straight as illustrated or it may have another shape (for example with a bend).

The several (preferably at least three) radial orifices 3 are close to the distal end 2, and they are preferably located on a same plane and clearly separated from each other to spread all around at 360° in order to reach the best spraying effect. The openings 3 may be on the same plane with respect to the axis of the cannula 1 or a different one as will be explained iater by reference to other embodiments of the invention.

Figure 2 illustrates a perspective view of the distal end of the cannula 1 with its tip 2 and the openings 3 distributed around 360°.

The cannula 1 comprises a channel 4 through which the product to be delivered by the cannula 1 may flow. To this effect, the channel 4 is connected to the openings 3 at its distal end and at its proximal end connected to a supply of product (see for example figure 6).

Figure 3 illustrates another embodiment of the cannula 11. In this embodiment, the tip 12 comprises a distal end 5 with a different shape than in previous embodiments: here the end 15 has a spherical shape to form an occlusion zone of the apex at the distal end of the tip 12. This occlusion zone is useful to protect the apical foramen of the tooth being treated for example from the irrigation solution being applied with the cannula.

The shape is not limited to a spherical shape and other shapes are possible: oval etc. depending on the teeth being treated and the patient's characteristics. !n the embodiment of figure 3, the openings 13 also have a greater size in the axial direction than in figures 1A-1 C and 2 forming so-called vents.

Figure 4 illustrates another embodiment of the cannula 21 , In this embodiment, the cannula 21 comprises two sets of openings, a first set 22 near the end of the distal tip 23 of the cannula 21 and a second set on a proximal side of the tip 23.

Each set 22, 24 preferably comprises three openings equally distributed over 360°, as described above for the preceding embodiments. This embodiment allows delivering more products (for example a solution) to the treated zone and at different locations or solutions that have to be mixed at the application site etc.

Also, it is possible to use more than two sets of openings 22, 24 depending on the circumstances and any different uses may be envisaged with this construction.

Of course the size of the openings of each set is represented in an exemplary manner in figure 4 and other sizes are possible (different sizes for each set, etc) and also the openings of each set may be in the same plane or a different one.

All combinations are possible within the scope of the present invention.

Figure 5 illustrates another embodiment of a cannula 31 according to the invention. In this embodiment, the cannula 31 comprises three openings 32 at the distal end 33 of the cannula 31 and the distal tip 34 has a spherical shape as in the embodiment of figure 3 for similar reasons. Again in this embodiment the shape of the distai tip may be different than illustrated and this principle is applicable to other embodiments described herein.

Figure 6 illustrate one possible use of the cannula described herein (applicable to all embodiments of said cannula 1 , 11 , 21 , 31 ). Typically, the cannula 1 may be mounted on a recipient 5, for example a spray can 5. Connection means 6 are to be provided, typically standard means such as Luer-Lock systems and other equivalents. Other features and characteristics of the cannuia of the invention (according to any embodiment described herein) are listed hereunder:

It is preferably Micro injected but of course, other equivalent methods may be envisaged.

It is made from a synthetic material that can be injected such as PE or PP or any other equivalent material.

It can be sterilized and is suitable to deliver the desired products in the desired environment.

It has preferably a conical shape with the apical third of adequate diameter to get close to the apical foramen and to allow backfiow of the irrigant without generating excessive pressure

It is preferably flexible to follow the shapes of the treated part (e.g. curved root canal), without causing injury.

It is preferably connectable on a recipient (e.g. spray can 5 see figure 6 or bottle) through a stainless steel tube curved near the distal part or a plastic connector part 6 (see figure 6) including a Luer Lock system or any other connecting system.

Figures 7 and 8 illustrate a possible use of the cannula 1 , 11 , 21 , 31 described above. These figures illustrate images of the use of the cannuia with a spray can 5 (figure 6) and show clearly three side liquid jets exiting the openings as described above. in these illustrative examples of use, the invention thus forms a spray system (see figures 6, 7 and 8) with the following aspects and features,

1. Automatic delivery system with appropriated pressure to clean the treated site 2. Preferable use of BOV {Bag On Vaive) technology for a constant delivery rate regardless of the position/orientation of the spray

3. Compiete protection of the irrigant solution against air (CO2), Sight (UV) and impurities (particles), inducing a unparalleled product stability (e.g. sodium hypochlorite) and a constant efficiency over time

4. Protection of the irrigant liquid against cross-contamination

The embodiments described in the present application are illustrative examples that should not be construed in a limiting manner. Other embodiments are possible within the scope of the present invention for exampie using equivalent means.

In addition, the different embodiments and their features may be combined together as desired or depending on the application.