Rotary instrument for dental implantology or endodontics, comprising a flexible part

Abstract

The invention relates to a rotary instrument (1) for dental implantology or endodontics, comprising at least one proximal part (10) configured to be connected to a rotational drive means, and a distal part (20), the shape of which is determined by the use of the instrument; the instrument comprising flexible means that make the instrument (1) flexible.

Description

[0001] ROTARY INSTRUMENT FOR DENTAL IMPLANTOLOGY OR ENDODONTICS COMPRISING A FLEXIBLE PART

[0002] Corresponding request

[0003] This application claims priority from earlier PCT international application No. PCT / IB2022 / 054490 filed on May 13, 2022 in the name of Frédéric WEHRLI, the contents of this earlier PCT application being incorporated by reference in its entirety into this application.

[0004] Field of invention

[0005] The present invention relates to dental implantology and endodontics and more specifically to the instruments used for this purpose.

[0006] State of the art

[0007] Rotary instruments for dental implantology and endodontics are surgical instruments that, when used in a well-defined sequence, allow dentists to perform dental treatments using a motorized device. In the case of implantology, these instruments are used to prepare and place a dental implant in a patient's jawbone. In endodontics, the corresponding rotary instruments allow the removal of the dental pulp from a tooth whose nerve is damaged (root canal treatment). Rotary instruments for implantology and endodontics include two functionally distinct parts illustrated in Figure 1, namely:

[0008] - A proximal part (also called "standard part"), for example in the form of a rod, provided with a standardized end, e.g. of the ISO 1797-1 type, allowing the instrument to be connected to a motor via a contra-angle for its rotation drive,

[0009] - A distal part (also called "specific part") whose design (for example its shape and / or size) derives from the main function of the instrument in question (drilling, reaming, tapping, screwing, filing, etc.).

[0010] In Figure 1 examples of rotary instruments for implantology or endodontics with highlighting of the functionally distinct parts (standard or proximal part 10 at the top, specific or distal part 20 at the bottom) are illustrated, from left to right: a drill, a reamer, a tap, an implant holder, a screwdriver for prosthetic screws, an extension and an endodontic file. Of course, these are examples of instruments and the application of the invention is not limited to these examples. As will be understood from the description below, the invention also applies to other equivalent instruments.

[0011] These instruments are, by design, completely rigid, or at least completely rigid in their proximal part, which is desirable for drills or reamers, but can become a major disadvantage for taps, screwdrivers for prosthetic screws, endodontic files and especially for implant holders (instruments for gripping an implant and inserting it into the bone). Indeed, for the latter, a certain flexibility in flexion can be an undeniable advantage in practice. Such flexibility would in particular make it possible to avoid hyper-guiding, which is often a source of significant stress in the instrument itself, but also in the bone and / or the implant. In some cases, these stresses can even lead to damage to the bone (necrosis), or even to fracture of the implant.

[0012] In practice, we are therefore faced with contradictory demands for such instruments: on the one hand, rigidity for certain operations and on the other hand, the need to have more flexible instruments for other operations, while maintaining standardisation of said instruments.

[0013] General description of the invention

[0014] An object of the present invention is to improve known instruments and to remedy the aforementioned problems.

[0015] Another object of the present invention is to provide standard instruments which can nevertheless be adapted to the wishes of users, in particular the dentists or surgeons concerned. The invention relates to a rotary instrument for dental implantology or endodontics comprising:

[0016] - a proximal portion configured to be connected to a drive means, such as a rotary motor via a contra-angle (or other equivalent means),

[0017] - a distal part whose shape is specific to the use of the instrument.

[0018] The invention is characterized in particular by the fact that the instrument comprises means allowing flexibility of said instrument.

[0019] In some embodiments, the flexible means are permanently flexible. In other embodiments, the flexible means can have at least two states: one rigid, the other flexible. Other states are possible, such as, for example, semi-rigid (or semi-flexible).

[0020] In embodiments, the flexible means are located on the proximal part of the instrument.

[0021] In embodiments, the flexible means are located, for example added, between the proximal part and the distal part of the instrument.

[0022] In other embodiments, the flexible means are located, for example added, between the proximal part and means for connecting the instrument to the drive means, such as a motor.

[0023] In embodiments, the flexible means include a joint.

[0024] In embodiments, the proximal portion is formed of a flexible part, or comprises a flexible part, said flexible part being sufficiently rigid in torsion for the intended use of the instrument. This material is, for example, Nitinol (nickel and titanium alloy) or another equivalent material (e.g., metal, metal alloy, etc.). In embodiments, the joint comprises a universal joint formed of at least two forks and a central nut of substantially spherical shape.

[0025] In embodiments, the universal joint comprises a pin and a pair of half-pins and the central nut is traversed by two perpendicular passages sized to receive the pin and the pair of half-pins.

[0026] In embodiments, the central nut comprises two perpendicular grooves and the forks comprise guides sized to slide in said grooves.

[0027] In embodiments, the flexible means comprise a spiral spring and / or a wire-shaped spring.

[0028] In embodiments, the instrument, e.g. its proximal part, comprises several flexible means.

[0029] In embodiments, the instrument may be a drill, reamer, tap, implant holder, screwdriver, file, adapter, or extender that can be connected to one or more other instruments.

[0030] Other embodiments and features of the invention are described in the claims and in the description which follows.

[0031] Detailed description of the invention

[0032] The invention is illustrated in more detail in the remainder of the description, in particular by means of several examples and embodiments, all of which should be considered illustrative and non-limiting.

[0033] Figure 1 illustrates examples of rotary instruments for implantology or endodontics.

[0034] Figure 2 illustrates an embodiment of the invention in the assembled state. Figure 3 illustrates the embodiment of Figure 2 in exploded view.

[0035] Figures 4 to 7 illustrate another embodiment of the invention.

[0036] Figure 8 illustrates another embodiment of the invention.

[0037] Figures 9 and 10 illustrate the use of embodiments of the invention for an implant holder (as a non-limiting example).

[0038] One embodiment is illustrated in Figure 2. In this embodiment, the proximal portion 10 of the instrument 1 comprises flexible means with an articulation 11 comprising a gimbal 12 coupled to a flexion spring 13.

[0039] As shown in Figure 3, the universal joint 12 of Figure 2 comprises a central nut 14 with which two forks 15, 15' are assembled using a pin 16, and two half-pins 16', 16". The pins 16, 16', 16" are inserted into passages 14', 14" of the nut 14 to achieve the articulation. Fixing means are of course provided so that the pins remain in place, once inserted.

[0040] The axes of the pin 16 and the two half-pins 16', 16" are preferably perpendicular in order to avoid any beating when rotating the instrument. This is desirable, because beating can induce stresses in the instrument 1, the bone or the implant, which would be precisely the opposite of what is sought by the invention.

[0041] The gimbal 11 can be located on the proximal part 10, or between the proximal 10 and distal 20 parts, which allows the joint to be completely free in flexion while having excellent torsional rigidity, a property necessary for good transmission of torque in the instrument.

[0042] The flexion spring 13, for its part, gives a semi-rigidity in flexion to the entire joint, ensuring a certain hold for the instrument 1. The spring 13 also allows the instrument 1 to bend reversibly. Figures 4 to 7 illustrate another embodiment of the invention using forks and a grooved sphere.

[0043] In Figure 4, a fork 30 is illustrated which is fixed on the proximal part 10 of the instrument. Figure 5 illustrates a grooved sphere 31 on which the fork 30 will fit (for example by forcing) as illustrated in Figure 6 by its guide 35 fitted into the groove 33.

[0044] Figure 7 illustrates the assembly of a second fork 32 on the sphere 31 (for example by forcing, the guide 36 sliding in the groove 34) opposite the fork 30 and placed at 90° so as to form an articulation similar to the universal joint of figures 2 and 3.

[0045] In this embodiment, it is possible to add in a variant a spring 13 as in the embodiment of figure 2.

[0046] For this purpose, shoulders are preferably added to hold the spring in position around the joint.

[0047] Figure 8 illustrates another embodiment of the invention. In this embodiment, a wire 40, for example made of NiTi or steel (or another equivalent material) is inserted through the forks 30, 32 and the sphere 31 in order to provide bending rigidity.

[0048] The flexible means of figures 4 to 8 may be located on the proximal part 10 of the instrument, or between the proximal 10 and distal 20 parts of the instrument or between the proximal part 10 and the means of connection to the motor 50 (as a means of driving the instrument), see figure 9.

[0049] The embodiment in which the proximal portion 10 is formed of a flexible part, or comprises a flexible part, said flexible part being sufficiently rigid in torsion for the intended use of the instrument is illustrated for example in Figure 10 where the proximal portion 10 is partially or totally formed of this flexible part. In the case of an implant holder 51, thanks to the flexible means illustrated in the embodiments above, the function of the instrument (inserting the implant into the bone) can be ensured even when the space available is restricted as illustrated in Figure 9.

[0050] In this case, the instrument holder (contra-angle, 50) is held at an angle (e.g. up to 30°) by the surgeon. As illustrated in Figures 9 and 10, thanks to the flexible joint, the implant holder 51, connected to the contra-angle, can perform its function even when the inter-occlusal height is low.

[0051] It goes without saying that the invention is not limited to the above-mentioned examples and uses and that the invention and its advantages can be used in different applications.

[0052] Embodiments have been described to provide a comprehensive understanding of the principles of structure, function, manufacture, and use of the systems and methods described in this application. One or more of these embodiments are illustrated in the accompanying drawings. The systems and methods specifically described in this application and illustrated in the accompanying drawings are non-limiting embodiments, and the scope of the present invention is not defined solely by the claims. Features illustrated or described in connection with one embodiment may be combined with features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention. A number of problems with conventional methods and systems are noted herein, and the methods and systems described herein may solve one or more of these problems.Additionally, while this invention has been described in conjunction with a number of embodiments, alternatives, modifications, equivalents, and variations that are within the spirit and scope of the present invention are also covered by this application.

Claims

Demands 1. Rotary instrument (1) for dental implantology or endodontics comprising at - a proximal part (10) configured to be connected to a rotational drive means, - a distal part (20) whose shape is determined by the use of the instrument, characterized by the fact that the instrument includes flexible means allowing flexibility of said instrument (1).

2. Instrument according to claim 1, characterized in that the flexible means have two states, a flexible state and a rigid state.

3. Instrument according to any one of the preceding claims, characterized in that the flexible means are located on the proximal part (10) of the instrument (1).

4. Instrument according to one of the preceding claims 1 or 2, characterized in that the flexible means are located between the proximal part (10) and the distal part (20) of the instrument (1).

5. Instrument according to one of the preceding claims 1 or 2, characterized in that the flexible means are located between the proximal part (10) and the means of connection to the drive means (50).

6. Instrument according to any one of the preceding claims, characterized in that the flexible means include a joint.

7. Instrument according to the preceding claim, characterized in that the joint comprises a universal joint formed of at least two forks (15, 15'; 30, 32) and a central nut (14; 31) of substantially spherical shape.

8. Instrument according to the preceding claim, characterized in that the universal joint comprises a pin (16) and a pair of half-pins (16', 16") and that the central nut (14) is traversed by two perpendicular passages (14', 14") dimensioned so as to receive the pin and the pair of half-pins (16, 16', 16").

9. Instrument according to any one of claims 1 to 7, characterized in that the central nut (31) has two perpendicular grooves (33,34) and the forks (30,32) have guides (35,36) dimensioned to slide in said grooves.

10. Instrument according to any one of the preceding claims, characterized in that the flexible means comprise a spiral spring (13).

11. Instrument according to any one of claims 1 to 9, characterized in that the flexible means comprise a wire-shaped spring (40).

12. Instrument according to any one of claims 1 to 11 in which the proximal part (10) comprises several flexible means.

13. Instrument according to any one of the preceding claims, said instrument being a drill bit, reamer, tap, implant holder, screwdriver, file, adapter or extension that can be connected to one or more other instruments.

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