Medical Device Handpiece Assembly

Abstract

A medical instrument handpiece assembly is described that includes a medical instrument handpiece (4) and a handpiece distal portion (22) adapted to receive an insert tip assembly (1), the insert tip assembly including a radio frequency identification device (3), an insert tip antenna (8), and an insert tip (2) adapted to interact with a portion of a patient's body. The medical instrument handpiece assembly (4) further includes a handpiece antenna (12) disposed in the handpiece distal portion (22) and a radio frequency signal providing means configured to provide a radio frequency signal to the handpiece antenna (12) and adapted to be transmitted by the handpiece antenna (12). The handpiece antenna (12) is configured to wirelessly communicate with the insert tip antenna (8) when the insert tip assembly is inserted into the handpiece (4) at an insertion region provided in the handpiece distal portion (22). The handpiece antenna (12) is a loop antenna or a segmented ring antenna comprising at least two handpiece antenna segments electrically arranged in series, wherein a first end of a first segment is operably connected to a first terminal of a radio frequency signal supply means and a second end of a last segment of the at least two handpiece antenna segments is operably connected to a second terminal of the radio frequency signal supply means to form a coil radiating structure around the insertion region configured to generate an electromagnetic field in the insertion region having a radio frequency dependent on the radio frequency signal. Each of the at least two handpiece antenna segments comprises a radiating metal element characterized by a respective inductance and electrically connected in series with a capacitive element having a capacitance to compensate for the effect due to the inductance of the radiating metal element on the current circulating in the coil of the handpiece antenna (12) and to match the characteristic impedance of the handpiece antenna (12) to a radio frequency generator in the control element (21) of the medical device (20). As noted above, a medical instrument (20) is further described that includes a control element (21), an insert tip assembly (1), and a medical instrument handpiece assembly.

Description

[Technical field]

[0001] The present invention relates to a handpiece assembly for a medical instrument.

[0002] In particular, the present invention relates to a handpiece assembly for a medical instrument having a handpiece adapted to receive by insertion of an insert assembly and a handpiece antenna.

[0003] For example, the present invention relates to a handpiece assembly for an ultrasonic piezoelectric element adapted for identifying an insert or an insert tip by a miniature radio frequency identification device.

[0004] Furthermore, the present invention relates to the context of ultrasound systems which find particular and advantageous application in medical-surgical fields (e.g. neuro-spinal, craniofacial, orthopedic, ENT), dental, surgical and non-surgical fields (e.g. oral surgery, implantology, dental hygiene and prophylaxis, etc.), but which can equally be used in the industrial or construction fields according to other embodiments.

[0005] More precisely, such a system can be used in fields where it is necessary to remove, abrade, cut or drill materials, for example calcified materials.

[0006] In the following, application refers to applications in the medical-surgical field (e.g. neuro-spinal, craniofacial, orthopedic, ENT), in the dental field, surgical and non-surgical (e.g. in oral surgery, implantology, dental hygiene and prophylaxis, etc.), but can equally be used in other embodiments in the industrial or construction field, for example in fields where it is necessary to remove, abrade, cut or drill mineralized materials such as bone, enamel, dentin, tartar and biofilms. [Background technology]

[0007] In the medical or dental field, especially in the surgical or implantology field, the power of ultrasound is applied in the fields of incision of hard (bone) and soft tissue, cauterization of blood vessels, and in dental prophylaxis for the removal of dental calculus.

[0008] By way of example only, with reference to the field of implantology, where a site for the insertion of a screw or other fixation system into a bone is prepared by using a rotary tool of the type described above, there are serious limitations both intraoperatively for the surgeon and postoperatively for the patient.

[0009] To name just a few, conventional instruments are problematic when operating in surgical sites with complex anatomical structures, difficult or limited surgical access, or near delicate anatomical structures such as nerves and blood vessels.

[0010] The large amount of mechanical energy generated by rotation and the considerable pressure that the surgeon must apply to the instrument result in potential damage to non-calcified structures, significant heat generation, frictional losses and resulting overheating of calcified tissue, and fatigue for the surgeon given the effort of precision and control required during the procedure.

[0011] The subject matter of the present invention relates to ultrasonic power systems for medical and dental applications, such as for use in oral implantology, but the invention can be applied in other areas of the medical and industrial fields as well.

[0012] The operation of most ultrasonic power systems is based on the transmission of longitudinal waves in an application means. Such waves are generated by a piezoelectric transducer and transmitted to the means via a concentrator or waveguide called an ultrasonic horn.

[0013] However, there are applications where bending, torsional or complex vibrations are used. In the dental field, for example, the longitudinal vibrations excited by an ultrasonic transducer are converted into bending vibrations through an asymmetrically shaped tip or tip of an insert. The incorporation of one or more curves into the contour of the tip of the insert has a dual purpose, namely, to allow good access to the interior of the oral cavity and to convert the longitudinal movement of the transducer into linear bending vibrations near the operating part of the tip of the insert.

[0014] In ultrasonic ablators, the flexing motion of the hook-shaped insert / insert tip is typically used to remove calcified deposits (tartar) from teeth. In ultrasonic scalpels (such as the "Piezosurgery device" from Mectron SpA), the lateral motion generated by the sickle-shaped insert / insert tip is used to precisely incise the mandible and other calcified tissues.

[0015] There are also ultrasonic ablators that remove tartar by both linear and elliptical vibrations, as described in DE 102005044074 A1 or EP 2057960 B1. In these systems, a vibratory motion with a bidirectional component is generated at the insert tip by flexural vibration of the transducer in orthogonal planes (see in particular EP 2057960 B1). The configuration of these flexural transducers refers to a previously disclosed concept in which lateral vibrations are induced by adjacent piezoelectric volumes inserted radially and axially with opposite polarity. [Mori, E. et al., “New Bolt Clamped Flexural Mode Ultrasonic High Power Transducer with One-Dimensional Construction”, Ultrasonics International 89 Conference Proceedings”; Watanabe, Y. et al., “A Study on a New Flexural-mode Transducer-solid Horn System and its Application to Ultrasonic Plastic Welding;, Ultrasonics Vol. 34, 1996, pp. 235-238; Yun, CH. et al “A High Power Ultrasonic Linear Motor using a Longitudinal and Bending Hybrid Bolt-Clamped Langevin Type Transducer”, Jpn. ]

[0016] In maxillofacial surgical procedures, ultrasonic vibrations at the tip of an insert are commonly used to cut bone tissue.

[0017] According to dental implantology protocol, an initial hole of reduced size is made and then gradually enlarged using a rotating drill of the augmentation section until a diameter compatible with the implant is reached.

[0018] The insert tips typically used in ultrasonic systems for procedures performed in the oral cavity have vibration amplitudes that are insufficient to perform all stages of implant site preparation. This limitation is inherent in the design of these instruments: the larger the section of the insert tip, the smaller the amplitude of vibrations generated, with the same handpiece. This inverse relationship between the section of the insert / insert tip and the vibrations is a limit to the applicability of the technology, especially in oral implantology, where drilling holes of several millimeters in diameter are required.

[0019] A further problem with the linear vibration of the insert tip is that it does not allow drilling of the mandibular structure unless a manual swing of the handpiece is applied in combination with it. Such an auxiliary movement is certainly difficult to generate by the surgeon inside the mouth and in any case does not quite meet the requirements of precision that clinical implant practice requires today.

[0020] Ultrasonic devices capable of incising biological tissue by excitation of torsional vibrations or a combination of torsional and longitudinal ultrasonic vibrations are known from US Pat. No. 7,374,552 B2, US Pat. No. 6,402,769 B1, US Pat. App. Pub. No. 2009 / 236938 A1, US Pat. App. Pub. No. 2011 / 0278988 A1. A common feature of these devices is that they all have a single geometrical axis of deployment and are essentially axisymmetric systems. In maxillofacial applications such as dental implants, the vibrating insert tips used in the oral cavity have a significantly asymmetric deployment relative to the transducer axis. Therefore, in these situations, it is not possible to generate torsional or longitudinal and torsional vibrations in the operating part of the insert tip according to the teachings of the above-mentioned invention (which is only valid for systems in which the transducer and the operating part are coaxial).

[0021] Slipszenko (US 2013 / 0253559 A1) has devised an ultrasonic system configuration in which torsional, bending or longitudinal vibrations are generated alternately in an ultrasonic scalpel for the treatment of soft tissues, with the generation axis perpendicular to the axis of the transducer. According to this solution, the transverse vibrations of a piezoelectric transducer can be converted into torsional, bending or longitudinal (longitudinal) vibrations by incorporating an ultrasonic horn or a waveguide mounted eccentrically with respect to the transducer axis. For the vibration transmission to be performed correctly, the rear diameter of the horn must be larger than the diameter of the transducer. Although it is possible to generate alternative vibration families in orthogonal planes, the specific requirements of compactness, ergonomics and weight of dental and medical equipment cannot be achieved by applying Slipszenko's solution. The large size and eccentric mounting of the ultrasonic horn would significantly limit the visibility in the oral cavity. Furthermore, in the Slipszenko solution, one or more waveguides are inserted between the scalpel and the transduction / vibration transmission horn to transmit the appropriate vibrations. Even if the number of these components is reduced to a minimum, the overall length of the device is still incompatible with applications in small, cramped, delicate spaces such as inside the oral or maxillofacial or neurospinal or cranial cavities.

[0022] Mishiro (JP 3-0373207) proposed an ultrasonic system for the removal of material that could theoretically find applicability in dental applications. The proposed solution is based on the working principle of a typical ultrasonic motor, where elliptical vibrations generated at the joint formed by an ultrasonic transducer coupled to a waveguide generate a rotation of an operating element (tool) that remains in contact with the tip of the waveguide. In the configuration illustrated in JP 3-0373207, the operating element, whose axis of symmetry can be perpendicular or parallel to the axis of the transducer, vibrates ultrasonically and allows the removal of material in addition to the rotation. The contact points between the operating element and the waveguide, to which the vibration movement is transmitted, correspond to the antinodes of the longitudinal and transverse vibrations generated by the rotation and generated at the transducer-waveguide joint. According to the configuration described in this solution, the operating element is supported by two pads located at an equal number of stationary nodes generated along the vibration element. Such a solution is complex in its implementation and does not seem to be suitable for applications in which the operating element (insert / insert tip) must be continuously used and replaced, such as in dental implants.

[0023] Furthermore, in the biomedical or medical device field, the need for continuous improvement in patient safety is strongly felt.

[0024] For this reason it must be ensured that inserts / insert tips for biomedical instruments (e.g. insert tips adapted to operate on a patient's teeth in dental medical instruments, or on bone in instruments for surgical use in areas such as the maxillofacial or neuro-spinal or cranial or orthopedic regions) always operate correctly and safely, come from a reliable manufacturer, are of the right type for the medical device, are not overused, etc.

[0025] For this purpose it is very important to have an insert / insert tip provided with an identification device, which is able to provide information about the insert tip and its operation to a control unit of the medical device.

[0026] In this regard, insert tips are known that are equipped with an RFID identification device and capable of wireless communication with the remainder of the medical device.

[0027] Solutions of this type are described, for example, in WO 2006082340, US 2011087605A1, US 2015147718A1, US 2009047624A1, US 2008044790A1, US 2009065565A1, and US 2015150647A1.

[0028] However, due to the particular characteristics of the inserts / insert tips used in this field, in particular their very small size and the presence of metal elements that make up the body of the insert tip, the communication capabilities offered by known solutions are not satisfactory for the needs or find no application available to users today.

[0029] More specifically, to ensure wireless communication of the RFID identification device with the rest of the medical device, i.e. for the excitation of the RFID identification device, a small antenna arranged at the tip of the insert acts like an inductance.

[0030] However, such inductance is disturbed by the presence of metal in the body of the insert tip, and also by possible liquids that may be present at the insert tip (e.g. physiological solutions, essentially saline solutions) that act as antagonists of the electromagnetic field, since they tend to absorb the electromagnetic field and, in the case of metals, symmetrically re-emit it, causing cancellation of the electromagnetic field in the boundary zone of the metal.

[0031] In summary, the overall result of such phenomena is a strong attenuation, or even cancellation, of the signal carried by the electromagnetic field in the vicinity of the insert tip antenna, which reduces the ability of communication between the RFID identification device and the remainder of the medical equipment, or even prevents such communication from taking place. This situation effectively undermines the advantages of RFID identification devices.

[0032] A further disadvantage of the aforementioned known solutions of inserts / insert tips with RFID identification devices lies in the difficulty of designing an insert tip antenna that operates at the frequencies required by UHF RFID communication, in accordance with the different standards established in various countries for this type of communication. In summary, there remains an unmet need for an insert / insert tip for a medical instrument equipped with an identification device capable of supporting effective and reliable communication with the remainder of the medical instrument.

[0033] Furthermore, the insert tips must be replaceably connected to the ultrasonic generator and, in order to be used repeatedly, they must be capable of being separated from the handpiece and placed in an autoclave, taking into account that this creates repeated and highly stressful processing cycles for any RFID identification devices connected to them.

[0034] Therefore, there remains a strong need for an insert / insert tip identification solution that is not only small in size and therefore able to fit into small distal portions of handpieces, i.e., narrow operating or intervention fields, but at the same time is highly resistant to the stresses imposed by autoclaving or similar processing cycles to sterilize them.

[0035] The aforementioned need for the RFID identification device at the tip of the insert to wirelessly communicate with the rest of the medical device places additional requirements on the medical device handpiece: such handpieces must be equipped with a radio frequency antenna that must be properly powered.

[0036] A reading antenna placed inside the handpiece must meet very strict size and operational requirements. In order to be able to accommodate the antenna in the handpiece, the size of the antenna must be miniaturized. This suggests the use of a ring or loop antenna.

[0037] However, small ring or loop antennas suffer from several problems. One of the main problems arises from the fact that the current circulating in the antenna ring tends to have so-called air gaps, i.e. points where the current undergoes phase reversal, depending on the operating frequency and the geometric dimensions. Such a phenomenon means that the antenna radiation is zero at some points, since the current is zero, and also causes other low radiation points, where the phase current is opposite to the primary current. Finally, this significantly reduces the transmission capability of the antenna.

[0038] A further fundamental need to minimize energy losses and the occurrence of line reflections due to environmental electromagnetic spurious phenomena arises from the need to ensure matching of antenna impedance in the UHF frequency range to the generators of the medical equipment, which is not easy to achieve in this application due to the small size of the antennas and the available space.

[0039] Finally, there arises a need to transmit, under impedance matching conditions, radio frequency signals inside the handpiece that are intended to feed the handpiece antenna and in the absence of a radio frequency connector.

[0040] Thus, there remains a strong need, and currently unmet, for an effective radio frequency signal transceiver solution in a handpiece to enable effective wireless communication with an insert tip radio frequency identification device. Summary of the Invention

[0041] The object of the present invention is to provide a handpiece assembly for medical instruments which overcomes the drawbacks mentioned above with reference to the background art and makes it possible to respond to the aforementioned needs particularly felt in the technical field considered.

[0042] Such an object is achieved by a handpiece assembly as claimed in claim 1.

[0043] Further embodiments of such a handpiece assembly are defined in claims 2 to 16.

[0044] It is a further object of the present invention to provide a medical instrument comprising the aforementioned handpiece assembly.

[0045] Such an object is achieved by a medical device according to claim 17.

[0046] A further embodiment of such a device is defined in claim 18.

[0047] Some of the main advantages arising from the present invention are: The location, thickness, and type of material allows for minimal increase in diameter at the insert tip without obstructing the clinician's view of the surgical site, ensuring and maintaining patient safety. The small dimensions and light weight of the material and the RFID chip, i.e. the material added to the metal at the tip of the insert, less than 15 grams, do not significantly affect the mechanical properties of the ultrasonic transducer when it is mechanically coupled to the tip of the insert, and therefore do not change the operating parameters such as the ultrasonic frequency and amplitude and power of the device, ensuring maximum and safe performance of the medical device at all times.

[0048] The material and location, small size, and weight of the RFID chip in the insert tip prevent degradation and ensure that the insert tip maintains its life, efficiency, and effectiveness.

[0049] A slight increase in the position and diameter of the insert tip does not affect the simplicity of the mechanical coupling between the insert tip and the transducer by a torque wrench or tool based on dynamic methods.

[0050] The type of RFID system material in the insert tip is suitable for the temperatures used in sterilization processes such as autoclaves and / or instrument washers.

[0051] The type of RFID coating material on the tip of the insert that interacts with the patient is biocompatible.

[0052] The reduced number of layers of the RFID system at the insert tip ensures simplicity of the manufacturing process and always provides a highly efficient system.

[0053] The reduction in thickness of the RFID system and the resulting minimal increase in diameter of the insert tip ensures a proper concentric area free of components surrounding the handpiece, ensuring that manufacturing process tolerances or deflections caused by excessive pressure applied by the clinician during surgery can allow mechanical parts of the transducer to come into contact with the insert tip, causing changes in the operating parameters of the device.

[0054] Identification of the insert tip by a unique non-writeable code on the RFID insert tip chip. Identification of the handpiece or handpiece antenna by a unique non-writeable code on the RFID handpiece chip.

[0055] Specifically with regard to patient safety, unique RFID identification in cooperation with medical devices enables: a. Ensure traceability of the insert tip or handpiece throughout its life cycle. b. An indication to the clinician that the insert tip and handpiece are appropriate and compatible. c. An indication to the clinician that the selected insert tip is appropriate and suitable for the selected type of intervention. d. An indication to the clinician of the performance of the insert tip, assessed with current and past usage and changes over time. e. Instructions to the clinician regarding the proper configuration of the medical device with respect to the insert tip in use. f. Clinical protocol and indication of each step of the procedure. g. Predictive Maintenance. h. Routine maintenance. i. Sharing data with manufacturers for statistical and continuous improvement of products and their usage conditions; j. Sharing data with manufacturers to update possible integration of new products or usage models for better efficiency and effectiveness of medical devices and medical systems with insert tips. k. Sharing data with universities, training centers etc. l. Written medical records and specific history of insert tips used in patient treatment.

[0056] Easy cleaning and sterilization of all RFID systems, both the insert tip and the distal antenna handpiece location, as well as the handpiece and the cord joining the medical device to the handpiece, following normal clinical protocols.

[0057] The ability to extract the antenna handpiece for maintenance and cleaning and sterilization in some embodiments.

[0058] The data transmission channel of the RFID system shares the connection for illumination of the handpiece cone at the distal location, if present, with the advantage of maintaining the flexibility of the cord joining the medical instrument to the handpiece without increasing the likelihood of anomalies caused by more connections and wires.

[0059] The present invention therefore provides a universal solution applicable both in dental surgery and prophylaxis, or maxillofacial surgery, orthopedics, neurospinal, ENT, craniofacial surgery, as well as other areas in the medical and industrial fields. [Brief description of the drawings]

[0060] Further characteristics and advantages of the handpiece for a medical instrument according to the invention will become apparent from the following description of preferred embodiments, given as illustrative and non-limiting examples, with reference to the attached drawings, in which: [Figure 1] FIG. 1 shows a schematic assembly of a medical instrument comprising an ultrasonic system with an excitation handpiece and a replaceable insert assembly, for example for use in dentistry or microsurgery. [Diagram 2] FIG. 2 shows a cross-sectional view of a portion of the handpiece assembly and insert assembly in FIG. 1 taken along line II-II in FIG. 1, with handpiece components such as a transducer, e.g., a piezoelectric transducer, highlighted. [Diagram 3] FIG. 3 shows an axonometric view of some of the components of the handpiece assembly and insert assembly of FIG. 1 with some parts separated, illustrating the internal handpiece components such as the insert assembly, the distal handpiece section cover, the light guide with the light collector, the handpiece antenna supported on the handpiece antenna connection element, and the piezoelectric transducer. [Figure 4] FIG. 4 is an axonometric view of only the central portion of the handpiece without the distal portion cover and handpiece antenna, highlighting the transducer shaft insertion connection tangs for interchangeable connection of the insert assembly. [Diagram 5]FIG. 5 is an axonometric view of the insert assembly. [Figure 6] FIG. 6 shows an axonometric view of the insert tip of FIG. 5 with the parts separated, highlighting the different layers of the radio frequency identification device. [Figure 7] FIG. 7 shows an enlarged plan view of the insert antenna in an extension of its planar outline suitable for wrapping and surrounding or partially surrounding the insert tip foot of the insert tip. [Figure 8] FIG. 8 is an axonometric view of a detail of an insert tip antenna with an identification chip connected thereto such that the identification chip is positioned with the entire body of the identification chip protruding from only one side of the extending surface of the insert antenna. [Figure 9] FIG. 9 is an axonometric view of a further embodiment of an insert antenna connected to an identification chip. [Figure 10] FIG. 10 is a detailed axonometric view of a detail of the insert antenna of FIG. 9 with an identification chip connected thereto, the identification chip being positioned with its entire body protruding from only one side of the extending surface of the insert antenna. [Figure 11] FIG. 11 is an axonometric view of a detail of an insert antenna with an identification chip connected thereto, with the identification chip positioned such that the entire body of the identification chip is at the same body level as the insert antenna and protrudes partially beyond, or beyond, only one side of the extension plane of the insert antenna. [Figure 12] FIG. 12 shows a top view of the insert assembly. [Figure 13] FIG. 13 shows a cross-sectional view of the insert of FIG. 12 taken along line XIII-XIII in FIG. 12, with the radio frequency identification device highlighted. [Figure 14] FIG. 14 shows an enlarged view of the portion designated by XIV in FIG. 13, with the layers of the radio frequency identification device highlighted. [Figure 15] FIG. 15 shows a cross-sectional view of an enlarged portion of FIG. [Figure 16]FIG. 16 shows a cross-sectional detail of an insert assembly according to a further embodiment. [Figure 17] FIG. 17 shows an axonometric view of the handpiece antenna with portions separated, along with the insert assembly with the various layers of components of the handpiece distal portion and the radio frequency identification device associated with the insert tip. [Figure 18] FIG. 18 shows an example of a continuous equivalent electrical circuit of the assembly formed by the RFID identification chip and the insert antenna. [Figure 19] FIG. 19 shows a parallel representation of an equivalent electrical circuit of another example of an assembly formed by an RFID identification chip and an insert antenna, including a connection model. [Figure 20] FIG. 20 shows a block diagram of an embodiment of an insert antenna and an identification chip. [Figure 21] FIG. 21 shows a block diagram of the medical instrument handpiece portion including the handpiece antenna. [Figure 22] FIG. 22 shows a simplified block diagram of the RF signal distribution mode in the handpiece. [Diagram 23] FIG. 23 shows a block diagram of a coaxial cable connection adapted to connect a handpiece to a medical system control unit. [Figure 24] FIG. 24 shows an equivalent circuit of an embodiment of the handpiece antenna. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0061] The term "miniaturized" refers to devices or components having a size between 50 and 800 micrometers, preferably between 100 and 600 micrometers.

[0062] The term "medical device" refers to electromechanical devices in which a piezoelectric handpiece activates mechanical movement of an insert tip at ultrasonic frequencies. These devices can be applied in several fields, listed below only as examples.

[0063] · Medical: surgery, especially in the neuro-spinal, cranio-maxillofacial, orthopedic, ENT and pediatric fields;

[0064] Dentistry, in particular surgery, dentistry in general, hygiene and prevention (especially removal of tartar, plaque and biofilm).

[0065] The functions performed by the instrument on the bone or teeth may, for example, mean: Disconnection; ·Perforation; Removal; ·erosion.

[0066] The functions performed by the instrument on the tartar / plate / biofilm may, for example, mean: Removal; Collapse.

[0067] In FIG. 1 , reference numeral 101 generally identifies an ultrasonic system 101 comprising a generator means 102 or control element 21 operatively connected to a transducer 25 for generating ultrasonic micro-vibrations which generate vibrations at a connected insert tip 2.

[0068] By way of example only, the ultrasound system 101 is a surgical or prophylactic instrument, such as a dental or medical instrument. According to other embodiments, the ultrasound system 101 is an industrial instrument.

[0069] An insert assembly 1 having a radio frequency identification device 3 is described below. Such an insert assembly 1 is adapted to be inserted into a handpiece 4 of a medical instrument.

[0070] The insert assembly 1 comprises, according to a general embodiment, an insert 2, a ferromagnetic layer 6, a dielectric layer 7, an insert antenna 8 and an identification chip 10.

[0071] The insert (insert tip) 2 is designed to interact with a part of the patient's body and comprises at least one insert metal tang 5 .

[0072] A ferromagnetic layer 6 is disposed in contact with or as part of said insert metal tongue 5 of the insert 2 .

[0073] According to an embodiment, the ferromagnetic layer 6 is glued to the insert metal tongue 5 of the insert 2. According to a different embodiment, the ferromagnetic layer 6 is attached to the metal tongue 5 by means of an intervening double-sided adhesive.

[0074] The ferromagnetic layer 6 comprises a ferromagnetic material.

[0075] The dielectric layer 7 is disposed in contact with the ferromagnetic layer 6 described above.

[0076] The insert tip antenna 8 is disposed in contact with the aforementioned dielectric layer 7 and comprises an insert antenna metallic element 9 extending along a predetermined, essentially planar contour P.

[0077] Such an insert antenna 8 is configured to receive and transmit electromagnetic fields within a predefined frequency range, either modulated or unmodulated.

[0078] The identification chip 10 is operatively connected to the insert tip antenna 8 described above and is configured to transmit information regarding the insert assembly 1 when activated.

[0079] Said ferromagnetic layer 6 is adapted to reduce or cancel the phenomenon of attenuation and / or distortion of the electromagnetic field caused by field parasite effects in the vicinity of the insert antenna 8 due to the interaction of the transmitted / received electromagnetic field with the metal parts of the insert metal tongue 5 of the insert 2 and / or with the liquid present in the insert 2 and / or with the insert antenna metal element 9.

[0080] The aforementioned ferromagnetic layer 6, dielectric layer 7 and insert antenna 8 form a transceiver 11 suitable for wirelessly connecting the identification chip 10 to a handpiece antenna 12 provided in a handpiece 4 into which the insert assembly 1 is inserted.

[0081] According to a further embodiment, the insert assembly 1 comprises an insert tip 2 and a radio frequency identification device 3 .

[0082] The insert assembly 1 is adapted to be inserted into a medical instrument handpiece 4 .

[0083] Insert assembly 1 is an insert tip 2 adapted to interact with a part of a patient's body, the insert tip 2 comprising an insert metal tang 5; and a radio frequency identification device 3.

[0084] The radio frequency identification device comprises a ferromagnetic layer 6 arranged on the side of the insert metal tongue 5 of the insert tip 2, in other words in direct contact with the insert metal tongue 5, taking into account a layer of adhesive or double-sided adhesive interposed between the ferromagnetic layer 6 and the insert metal tongue 5.

[0085] The ferromagnetic layer 6 comprises a ferromagnetic material and is in particular adapted to reduce or cancel the phenomenon of attenuation and / or distortion of the electromagnetic field caused by electric field parasitic effects in the vicinity of the insert antenna 8 due to the interaction of the transmitted / received electromagnetic field with the metal parts of the insert metal tongue 5 and / or with the liquid present at the insert tip and / or with the insert antenna metal element 9.

[0086] The radio frequency identification device further comprises a dielectric layer 7 arranged in contact with the ferromagnetic layer 6 .

[0087] The radio frequency identification device further comprises an insert antenna 8 arranged in contact with the dielectric layer 7 and comprising an insert antenna metallic element 9 extending along a predetermined substantially planar contour P.

[0088] The insert antenna 8 is configured to receive and transmit electromagnetic fields within a given frequency range, either modulated or unmodulated.

[0089] The radio frequency identification device further comprises an identification chip 10 .

[0090] Identification chip 10 is operatively connected to insert antenna 8 and is configured to transmit information regarding insert assembly 1 when activated.

[0091] Additionally, the medical instrument handpiece 4 includes a handpiece antenna 12 .

[0092] The ferromagnetic layer 6 , the dielectric layer 7 and the insert tip antenna 8 form a transceiver 11 adapted to wirelessly connect the identification chip 10 to a handpiece antenna 12 of the handpiece 4 .

[0093] Advantageously, the ferromagnetic layer 6 and / or the dielectric layer 7 comprise a chip housing 13 .

[0094] The identification chip 10 is operatively connected to the insert antenna 8 so as to avoid protruding from at least one first or outer surface 14 of the substantially flat contour P of the insert antenna metallic element 9 of the insert antenna 8 .

[0095] Furthermore, the identification chip 10 together with its chip portion 16 protrudes from the inner surface 15 of the insert antenna metal element 9 of the insert antenna 8 and protrudes from the opposite side relative to the outer surface 14 of the substantially flat contour P.

[0096] Advantageously, the protruding chip portion 16 is accommodated in the chip housing 13, making the radio frequency identification device particularly compact and space-saving.

[0097] Furthermore, the insertion of protruding chip portion 16 into chip housing 13 further shields identification chip 10, making it more robust against external electromagnetic interference, and also makes the assembly of identification chip 10 and insert antenna 8 mechanically more robust against external stresses and more thermally protected from thermal stresses imposed, for example, by a sterilization autoclave or a washer-disinfector.

[0098] According to an embodiment, the ferromagnetic layer 6, the dielectric layer 7 and the insert antenna 8 form a stack with dimensions ranging between 50 and 800 micrometers, preferably between 100 and 600 micrometers, adapted to be placed on top of the insert with a dimension transverse to its longitudinal extension, for example a radial dimension on one of its longitudinal extension axes not exceeding 6,400 micrometers. These values ​​refer to the thickness of the stack in a plane, so they indicate the increase in radius of the insert tip 2, which is cylindrical for example, while the radial dimension of the insert tip is the diameter of the metal of the insert tip 2, which is cylindrical for example.

[0099] According to an embodiment, the thickness of the ferromagnetic layer 6, i.e. its radial dimension relative to the longitudinal extension of the insert tip 2, is in the range between 20 and 400 micrometers, preferably between 50 and 300 micrometers.

[0100] According to an embodiment, an inner insulating layer 17 , for example a double-sided adhesive, is arranged internally with respect to the ferromagnetic layer 6 , i.e. between the insert metal tongue 5 and the ferromagnetic layer 6 .

[0101] According to an embodiment, the dielectric layer 7 is a double-sided adhesive.

[0102] According to an embodiment, the insert antenna 8 is made of aluminum.

[0103] According to an embodiment, the insert antenna 8 has a flat rectangular shape with rectangular surface dimensions of the short side between 1 mm and 6 mm, preferably between 2 mm and 4 mm, and the long side between 10 mm and 30 mm, preferably between 12 mm and 25 mm, respectively, with a thickness of the insert antenna 8 of less than 50 micrometers.

[0104] According to an embodiment, the radio frequency identification device 3 further comprises an outer insulating layer 18 arranged externally with respect to the ferromagnetic layer 6 , the dielectric layer 7 , the identification chip 10 and the insert antenna 8 .

[0105] According to an embodiment, the radio frequency identification device 3 further comprises a protective layer 19, which is for example biocompatible and arranged externally with respect to the ferromagnetic layer 6, the dielectric layer 7, the identification chip 10 and the insert antenna 8.

[0106] According to an embodiment, the radio frequency identification device 3 further comprises a protective layer 19, for example biocompatible, arranged externally relative to the outer insulating layer 18.

[0107] According to an embodiment, the outer insulating layer 18 is made of PVC (polyvinyl chloride), or PET polyethylene terephthalate, or polyamide, such as Kapton®.

[0108] According to an embodiment, the protective layer 19 is biocompatible, for example a paint or an epoxy compound having one or more components.

[0109] According to an embodiment, the ferromagnetic layer 6, the dielectric layer 7 and the insert antenna 8 form a stack.

[0110] According to an embodiment, the ferromagnetic layer 6, the dielectric layer 7, and the insert tip antenna 8 are wrapped around the insert metal tongue 5 to form a structure that is substantially concentric around the central metal element 5. The term "concentric" does not mean that the structure completely surrounds the central metal element, nor does it mean that it must be completely concentric with it, but only that it surrounds the inner metal element along a portion of the circumference of the central metal element, e.g., to allow for a minimum extension of the insert antenna around the circumference of the insert tip, an extension compatible with the desired transmission and reception.

[0111] According to an embodiment, such ferromagnetic layer 6 comprises ferrite. According to an embodiment, the ferromagnetic layer 6 is actually made of a thin sintered ferrite or polymer matrix (polymer-based) with high magnetic permeability mixed with micrometer-sized magnetic powders dispersed throughout the material.

[0112] According to an embodiment, the ferromagnetic layer 6, the identification chip 10 is an RFID tag chip.

[0113] According to an embodiment, the identification chip 10 is of parallelepiped shape with a base dimension between 50 and 1200 micrometers, preferably between 100 and 1000 micrometers, and a thickness of less than 300 micrometers.

[0114] According to an embodiment, the insert assembly 1 is configured to operate in association with medical devices for dentistry or prophylactic or implantology, and for medical applications in maxillofacial, craniofacial, neuro-spinal, or orthopedic or other anatomical areas.

[0115] The invention further relates to a medical instrument 20 comprising a medical instrument handpiece 4 equipped with a control element 21, a handpiece antenna 12 for RF transmission and reception, and an insert assembly 1 according to any one of the above-mentioned embodiments.

[0116] According to an embodiment, the insert assembly 1 is operatively and mechanically separably connected to the handpiece 4 .

[0117] According to an embodiment, the medical instrument handpiece 4 comprises a handpiece distal portion 22 terminating in a handpiece distal end 30, a handpiece central portion 23, and a handpiece proximal portion 24. A transducer 25, e.g., a piezoelectric transducer, is connected to an ultrasonic generator or control unit 26. The transducer 25 is received in the medical instrument handpiece 4, and an insert attachment tang 27 protrudes through the handpiece distal portion 22 which removably connects to the insert 2 so as to resonate the insert 2 upon activation.

[0118] According to an embodiment, the handpiece distal portion 22 comprises a handpiece antenna 12. According to an embodiment, the handpiece antenna 12 is movably connected to the handpiece 4. According to an embodiment, the handpiece antenna 12 is housed in the handpiece 4 and is fixedly connected to the handpiece 4.

[0119] According to an embodiment, the handpiece distal portion 22 includes a handpiece antenna connection element 28 .

[0120] The handpiece antenna 12 is supported by and electrically connected to the handpiece antenna connection element 28 and projects from the handpiece antenna connection element 28 toward the handpiece distal end 30 so as to at least partially overlap the insert antenna 8 when the insert tip is connected to the handpiece 4.

[0121] According to an embodiment, handpiece antenna 12 protrudes from handpiece antenna connection element 28 towards handpiece distal end 30 so as not to overlap insert antenna 8 when the insert tip is connected to handpiece 4 .

[0122] According to an embodiment, the handpiece antenna connection element 28 is electrically connected to the handpiece in a fixed or removably manner. The handpiece antenna connection element 28 may include at least one LED 29.

[0123] According to an embodiment, each handpiece antenna connection element 28 does not include an LED 29 .

[0124] According to an embodiment, when the handpiece antenna connection element 28 comprises at least one LED 29, the handpiece antenna connection element 28 may comprise a light directing element 31 with at least one light concentrator 32 associated with the handpiece antenna connection element 28 to direct the light of the at least one LED 29 at the handpiece distal end 30 to illuminate the working area of ​​the medical instrument 20.

[0125] According to an embodiment, the light-guiding element 31, the handpiece antenna connecting element 28 and the handpiece antenna 12 are covered by a distal handpiece portion cap 33, for example made of aluminum, which is removably connected to the distal handpiece portion 22.

[0126] According to an embodiment, the medical instrument 20 connects the handpiece 4 to the ultrasound generator or control unit 21 by a connecting cable 34 for electrical and fluid supplies.

[0127] According to an embodiment, the medical device handpiece 4 interchangeably accepts inserts / insert tips 2 that are mechanically coupled to an ultrasonic micro-vibration generating device, e.g., a piezoelectric transducer 25, operating at different frequencies and ranges of power and ultrasonic amplitude as a function of the type of insert 2 selected.

[0128] According to an embodiment of the insert assembly, the insert antenna 8 is an RF antenna adapted to operate at radio frequencies and the identification chip 10 is a radio frequency identification chip, the aforementioned frequency range including one or more radio frequency ranges.

[0129] According to an embodiment of the insert assembly 1, the aforementioned transceiver device (hereinafter also referred to as the “transceiver structure”) formed by the ferromagnetic layer 6, the dielectric layer 7, and the insert antenna 8 can be modeled by an electrical circuit whose electrical parameters depend on the size and material of the ferromagnetic layer 6.

[0130] According to an implementation option, the aforementioned transceiver structure formed by the ferromagnetic layer 6, the dielectric layer 7, the insert antenna 8 and the identification chip 10 can be modeled by an electric circuit LC, where the parameters of inductance La and capacitance Cc depend on the dimensions and materials of the ferromagnetic layer 6, the dielectric layer 7, the insert antenna 8 and the identification chip 10. In particular, the inductance La mainly depends on the dimensions and materials of the ferromagnetic layer, the dielectric layer and the insert antenna, while the capacitance Cc mainly depends on the identification chip 10.

[0131] In this case, the frequency range in which the transceiver structure can operate depends on the aforementioned parameters of inductance La and capacitance Cc.

[0132] According to the option of using the insert assembly, the operating frequency range of the transceiver structure includes the frequency range of the UHF RFID band (between 860 MHz and 960 MHz), such as the ETSI European technical standard of 865-868 MHz, the FCC FHSS North American technical standard of 902-928 MHz, the MIC LBT Japanese technical standard of 916.7-920.9 MHz and 916.7-923.5 MHz, the ANATEL FHSS Brazilian technical standard of 902-907.5 MHz and 915-928 MHz, and the MII FHSS Chinese technical standard of 920.5-924.5 MHz.

[0133] According to implementation options of the insert assembly, the thickness of the ferromagnetic layer, i.e. the radial dimension for the insert, ranges between 20 and 400 micrometers.

[0134] More preferably, the thickness of the ferromagnetic layer, i.e. the radial dimension relative to the insert, is in the range between 50 and 300 micrometers.

[0135] According to various possible implementation options of the insert assembly, the ferromagnetic layer is actually made of a thin sintered ferrite or polymer base of high magnetic permeability mixed with micrometer-sized magnetic powders dispersed throughout the material.

[0136] According to an embodiment of the insert assembly 1, the identification chip 10 is an RFID chip, for example an RFID chip known per se.

[0137] According to an embodiment of the insert tip assembly 1, the identification chip 10 is configured, when excited, to store and transmit, via the aforementioned transceiver structure, one or more items of information belonging to the following sets:

[0138] Unique and unalterable identification code information for the insert assembly; Information regarding the manufacturer and traceability of the insert assembly and / or the type or types of medical devices with which the insert assembly can operate; Information regarding the operating frequency range over which the transceiver structure of the insert assembly is capable of operating; Information that the insert tip screwed into the handpiece is suitable for the type of procedure selected in the medical device; Information about usage mode and usage time history; Information regarding the integrity of the insert assembly to maximize the efficiency and effectiveness of the clinical surgical phase for the patient; Information regarding the integrity of the insert assembly for proper scheduled maintenance; Information regarding whether the insert assembly is properly inserted, if any, into each handpiece; Information regarding the operating parameters of the insert assembly in the presence of abnormal operating conditions and / or error or warning messages.

[0139] According to examples of use, the insert assembly is configured to operate in conjunction with dental, prophylactic or implantology medical devices, and medical devices for maxillofacial, craniofacial, neuro-spinal, or orthopedic or other anatomical medical applications.

[0140] A medical device according to the present invention is described herein.

[0141] Such a medical device comprises a control unit, a handpiece having a handpiece antenna, and an insert assembly according to any one of the above-mentioned embodiments, in which such insert assembly is operatively and mechanically connected to the aforementioned handpiece of the medical device, and the insert antenna is configured to wirelessly communicate with the handpiece antenna.

[0142] Further information regarding possible embodiments of the insert assembly is provided below with reference to FIGS.

[0143] 18 shows the equivalent electrical circuit in series representation of the assembly formed by the RFID identification chip 10 and the insert antenna 8. Neglecting the total parasitic capacitance, the identification chip 10 is modeled by a capacitance Cc and a resistance Rc, i.e. the insert antenna 8 is modeled by an inductance La and a resistance Ra. In fact, the total electrical circuit is an LC circuit, while the resistive components take into account the "non-idealities", i.e. the radiative system losses and the energy losses.

[0144] Such a model represents an embodiment in which the radio transceiver structure is based on short-range wireless UHF (860 MHz-960 MHz) technology and utilizes a reactive portion of the electromagnetic field operating as a so-called "magnetic antenna" preferably having a segmented closed-loop geometry.

[0145] From the point of view of fields, the ferromagnetic layer has the function of insulating the radio transceiver structure from the metallic parts of the insert / insert tip body, thus preventing the generation of a reflected antagonist field caused by stray currents induced by the variable primary magnetic field, thus avoiding the phenomenon of attenuation or nulling of the total electromagnetic field.

[0146] In other words, the addition of a ferromagnetic layer with complex effective magnetic permeability modifies the magnetic profile by affecting the mutual inductance and self-inductance. By appropriately selecting the materials and dimensions of the ferromagnetic layers (e.g., as in the implementation options described above), it is possible to have the freedom to optimize the design of the transceiver structure, maximize the overall field strength present in the antenna, and improve communication if desired.

[0147] From the electrical point of view of "lumped parameters", the ferromagnetic layer determines the effect of increasing the inductance of the LC system (where C is dominated by the chip). This feature, in turn, determines the additional effect of lowering the resonance frequency of the "antenna chip" system, which has the advantage of bringing it into the limited range required by the UHF band (thus facilitating and improving the design of the transceiver structure, making it more easily adapted to the desired application).

[0148] 19 shows a parallel representation of an equivalent electrical circuit of another example of an assembly formed by an RFID identification chip 10 and an insert antenna 8, also including a model of the connection G. This representation includes system parasitics such as the antenna parasitic capacitance.

[0149] In particular, in this case the transceiver structure comprising the insert antenna 8 and the ferromagnetic layer 6 is modelled by an RLC circuit, whilst the identity chip 10 is modelled by an RC circuit.

[0150] From a practical point of view, the considerations already made above with respect to FIG. 18 apply.

[0151] FIG. 20 is a block diagram of an embodiment of the insert antenna 8 and the identification chip 10.

[0152] In particular, the magnetic field lines are highlighted around the near field antenna 8 .

[0153] In this embodiment, the identification chip 10 comprises an analog front end (power management element 71 and modulator / demodulator element 72) and a digital control section, with a controller 73 (of a type known per se, such as an RFID tag, for example) and a non-volatile memory 74.

[0154] As indicated in paragraph 52 (ix-x-xi), the non-volatile memory 74 is configured to store usage information such as cumulative total usage time and statistically estimated wear so as to provide the clinician with an updated status even when the insert / insert tip is used in a location other than the original location (e.g., a clinician with multiple clinic rooms) but always with appropriate and compatible medical equipment.

[0155] According to certain implementation options, to ensure data integrity and authenticity, the data can be stored in non-volatile memory 74 even after an encryption or password authentication process that can only be decoded by appropriate medical equipment with which the insert can be associated.

[0156] Described below is a handpiece assembly for a medical instrument comprising a handpiece 4 for a medical instrument. Such a handpiece 4 comprises a handpiece distal portion 22 suitable for receiving by insertion an insert assembly 1 (e.g. an insert assembly according to the embodiments described above) comprising a radio frequency identification device 3, an insert antenna 8 and an insert 2 adapted to interact with a part of a patient's body.

[0157] The handpiece assembly for the medical instrument further comprises a handpiece antenna 12 disposed in the handpiece distal portion 22 and a radio frequency signal providing means configured to provide to the handpiece antenna 12 a radio frequency signal adapted to be transmitted by the handpiece antenna 12.

[0158] The aforementioned handpiece antenna 12 is configured to wirelessly communicate with the insert antenna 8 at an insertion region R provided in the handpiece distal portion 22 when the insert assembly is inserted into the handpiece 4 .

[0159] Said handpiece antenna 12 is a single coil loop antenna, preferably a segmented ring antenna, comprising at least two handpiece antenna segments S1, S2, hereinafter referred to as the "first segment" S1 and the "last segment" S2, arranged electrically in series, a first end 41 of said first segment S1 of said at least two handpiece antenna segments being operatively connected to a first terminal 51 of a radio frequency signal supplying means, and a second end 42 of said last segment S2 being operatively connected to a second terminal 52 of said radio frequency signal supplying means to constitute a coil radiating structure configured to generate in said insertion region R around said insertion region R an electromagnetic field having a radio frequency dependent on said radio frequency signal.

[0160] Each of the single coil loop or said at least two handpiece antenna segments (S1, S2) comprises a radiating metal element (S11, S21) characterized by a respective inductance L electrically connected in series with a capacitive element (S12, S22) having a capacitance C so as to compensate for the effect due to the inductance L of the radiating metal element on the current circulating in the coil of the handpiece antenna 12 in the UHF RFID range (860 MHz-960 MHz).

[0161] According to an embodiment of the handpiece assembly, the aforementioned capacitance C of each capacitive element (S12, S22) is such as to further match the characteristic impedance of the handpiece antenna 12 to a radio frequency generator located in the control element 21 of the medical device 20 operatively connected to the handpiece assembly.

[0162] According to the embodiment of the handpiece, the handpiece antenna 12 further comprises an input impedance matching first electrical circuit network 43 provided between the first terminal 51 and the second terminal 52 of the signal supply means and the first end of the first segment 41 and the second end of the last segment 42 of the handpiece antenna 12; and further comprises an antenna impedance matching second electrical circuit network 44 provided in the segmented antenna ring and electrically connected in series between two segments (S1', S2') of the at least two handpiece antenna segments.

[0163] According to implementation options, said input impedance matching first electrical network 43 comprises an inductance-capacitance circuit LC or a capacitance circuit.

[0164] According to implementation options, the aforementioned antenna impedance matching second electrical circuitry 44 comprises a resistance-capacitance circuit RC or a capacitance circuit configured to adapt the antenna impedance to a desired impedance value and adapted to optimize the transmission of the radio frequency signal generated by the medical device 21 and conveyed along the cable 34 and the handpiece 4.

[0165] For example, such impedance values ​​in the UHF RFID range (860 MHz-960 MHz) can be expressed as a complex number Z=R+iX having a modulus between 20 and 80 ohms, preferably between 45 and 55 ohms.

[0166] According to an embodiment of the handpiece 4, the aforementioned radiating metal elements (S11, S21) of the segmented ring antenna can be modeled by an equivalent electrical circuit with an inductance L and a resistance R, in which the inductance is in the range between 2 nH and 30 nH, preferably between 4 nH and 20 nH.

[0167] The aforementioned capacitance elements (S12, S22) are expressed as LC = (ω 2 ) -1 , where ω=2πf, and f is the operating resonant frequency, and is a capacitor having a capacitance between 1 pF and 12 pF, preferably between 2 pF and 10 pF.

[0168] According to an embodiment of the handpiece 4, the aforementioned handpiece antenna 12 is configured to operate in a frequency range in the UHF RFID band between 860 MHz and 960 MHz.

[0169] According to an implementation option, all antenna segments are characterized by equal capacitance C and inductance L values.

[0170] According to another implementation option, the inductance value L of the radiating metallic element varies from segment to segment and the capacitance value C of the capacitive element varies from segment to segment depending on the inductance value L of the respective segment.

[0171] According to an embodiment, the handpiece assembly 4 further comprises a handpiece identification device 45 adapted to communicate wirelessly or by wire with the handpiece antenna 12 described above.

[0172] Such a handpiece identification device 45 may be configured to provide handpiece antenna identification information and / or information on the operating status and / or operating frequency of the handpiece antenna 12 .

[0173] According to an embodiment of the handpiece assembly 4, the aforementioned radio frequency signal supply means comprises a signal guide 50 and a handpiece antenna connection element 28.

[0174] According to a preferred embodiment, the signal guide comprises a microstrip printed circuit with an impedance of 50 ohms arranged to carry the radio frequency supply signal from the connecting cable 34 to the handpiece antenna 12 between the handpiece 4 and the control element 21 of the medical device 20.

[0175] According to another embodiment, the signal guide 50 comprises a miniaturized coaxial cable with an impedance of 50 ohms.

[0176] A handpiece antenna connection element 28 connected to the signal guide 50 and to the handpiece antenna 12 comprises a first terminal 51 and a second terminal 52 of a radio frequency signal supply means.

[0177] According to an embodiment, the aforementioned microstrip circuit is a 50 ohm impedance controlled circuit with metal tracks less than 1 millimeter thick.

[0178] The aforementioned microstrip circuits can be produced by multilayer printed circuits according to techniques known per se.

[0179] According to a particular implementation option, said microstrip circuits with metal tracks have a thickness between 0.2 mm and 1.0 mm, preferably between 0.35 mm and 0.85 mm, and are made of Vetronite material type FR4 or Kapton-polyamide or Rogers.

[0180] According to an embodiment of the handpiece assembly, the aforementioned coil radiating structure of the handpiece antenna has a diameter of less than 30 mm so as to be accommodated within the inner wall of the handpiece distal portion 22 .

[0181] According to an embodiment of the handpiece assembly, the handpiece antenna 12 is fixedly or releasably connected to the handpiece distal portion 22 .

[0182] According to a particular embodiment of the handpiece assembly, the handpiece antenna 12 is made from a T-shaped or G-shaped flexible-rigid multi-layer printed circuit board, where a flexible portion (e.g., Kapton-polyamide) extends from a rigid portion (e.g., Vetronite type FR4 or Rogers).

[0183] When the aforementioned flexible-rigid multi-layer printed circuit board is in place inside the cone of the handpiece, the upper portion of the T-shape or Г-shape wraps around the cone of the light guide, overlapping the edges of the upper portion of the T-shape or Г-shape and allowing electrical contact (i.e., forming a loop or segmented ring), for example by tin or ultrasonic welding.

[0184] In this case, a tag (TAG) is placed exactly at the junction of the vertical and horizontal segments of the T-shape or Г-shape and electrically connected via a decoupling capacitor. Such a tag performs the functions of the handpiece identification device described above and performs the functions of identifying the handpiece antenna cone for purposes of, for example, traceability, verifying correct use for a geographical area (e.g., depending on the destination continent or country (e.g., Europe, USA or Japan), the handpiece antenna may need to be adapted to the local operating frequency, which can be achieved with a specific set of antenna capacitors with appropriate values ​​adapted to the correct operating frequency), and compatibility of the insert tip for clinical use.

[0185] Further information regarding possible embodiments of medical instrument handpiece assemblies is provided below with reference to FIGS.

[0186] 22 shows a simplified block diagram of the RF signal distribution mode in the handpiece, which shows a microstrip circuit 50 comprising the multi-layer flexible circuit of the previous embodiment, which in turn comprises an impedance matching circuit in the printed circuit 53 and a respective RF 54 impedance matching network at each end of such circuit 53.

[0187] In this embodiment, the microstrip 50 circuit has the capability of transmitting a composite signal containing both the RF signal for the handpiece antenna and the DC signal for the light cone LED lighting circuit with the lowest possible losses.

[0188] Microstrip or stripline circuits are an established technology in the field of controlled impedance printed circuit boards where high frequency signal integrity must be maintained. In addition, the microstrip circuits have very small dimensions (especially thickness) and therefore fit into the small internal space available in handpieces. For example, microstrips are designed to obtain thicknesses ranging between 0.2-1.0 mm, preferably between 0.35-0.85 mm.

[0189] Upstream of the microstrip circuit (reference point indicated as B in Figures 22 and 23) is a minimum RF range connector 55 with pin connections configured to connect to a corresponding minimum RF range connector 65 with pin connections coupled by a coaxial cable 60.

[0190] Such a coaxial cable 60 (shown in FIG. 23) is used to connect the handpiece 4 to the control element 21 of the medical device and to transmit RF signals between the handpiece 4 and the control element 21 .

[0191] Returning to FIG. 22, downstream of the microstrip circuit (reference point shown as C in FIG. 22 and FIG. 21) is another minimum RF range connector 55 having pin connections that is configured to connect to a corresponding minimum RF range connector 55 having pin connections that are coupled to an RF-DC decoupling network (or decoupler) 56.

[0192] Indeed, in this case the flexible rigid circuit also provides an RF-DC decoupler 56 which separates the RF and DC components and routes the DC component to the light cone LED lighting circuit 57 and the RF component to the handpiece antenna 12 (as shown in FIG. 21).

[0193] The aforementioned minimum RF range connector 55 with pin connections is configured to minimize insertion area to minimize RF radiation losses at the interconnection points and enable adequate transmission capability even in situations where known RF connectors for coaxial cables cannot be used due to size.

[0194] FIG. 21 also shows functional blocks corresponding to the handpiece antenna 12, which is a near field antenna with an ignition circuit 57 and optical signal guide DC 58, as well as an RF input impedance adjustment 59.

[0195] FIG. 21 also shows a functional block corresponding to an identification device (tag) of the handpiece 45, which is connected in wireless near-field mode or in wired mode to the handpiece antenna 12 by a decoupling capacitor.

[0196] FIG. 24 illustrates an equivalent electrical circuit for a handpiece antenna, according to an embodiment.

[0197] Below, a medical instrument 20 is described comprising a control element 21, a medical instrument handpiece 4 according to any one of the above-mentioned embodiments, and an insert assembly 1 comprising a radio frequency identification device 3, an insert antenna 8 and an insert 2 suitable for interacting with a part of a patient's body.

[0198] The insert assembly 1 described above is operatively separate from and mechanically connected to a handpiece 4 of a handpiece assembly.

[0199] The aforementioned insert antenna 8 and handpiece antenna 12 are configured to wirelessly communicate with each other at radio frequencies.

[0200] According to an embodiment, the medical device 20 is configured such that when the insert assembly 1 is connected to the handpiece 4, the insert antenna 8 is positioned in proximity to the handpiece antenna 4 in the aforementioned insertion region R where the radio frequency electromagnetic field generated by the handpiece antenna 4 exists in a radiated state.

[0201] As may be noted, the objectives of the present invention, with its structural and functional characteristics, are fully achieved by the system chain (insert assembly 1 - handpiece assembly 22; 4; 24 - cable 34 - medical device 20 - control device 21) developed and described above.

[0202] Indeed, thanks to the features detailed above, the insert assembly makes it possible to reduce and minimize undesirable phenomena that impair the communication between the insert assembly and the rest of the medical device.

[0203] In particular, from the point of view of fields, the ferromagnetic layer has the function of isolating the radio transceiver structure from the metallic parts of the insert body and preventing the generation of reflected opposing (canceling) magnetic fields, thus avoiding the phenomenon of attenuation or nulling of the total electromagnetic field (which is a problem in the prior art).

[0204] The addition of ferromagnetic layers with composite effective permeability modifies the magnetic profile by affecting the mutual inductance and self-inductance. By appropriately selecting the materials and dimensions of the ferromagnetic layers (e.g., as in the implementation options described above), it is possible to have the freedom to optimize the design of the transceiver structure, maximizing the overall field strength present at the antenna and improving communication where necessary.

[0205] Ultimately, this leads to improved patient safety requirements, which are of great importance in the indicated technical fields and fields of application, in particular in the dental and medical fields defined in the document.

[0206] From the electrical point of view of "concentrated parameters", the ferromagnetic layer increases the inductance of the system LC (where C stands for chip). This feature then determines the further effect of lowering the resonance frequency of the "antenna-chip" system, which has an additional advantage and reaches the further objective of bringing it within the limited range required by the UHF band, thus facilitating and improving the design of the transceiver structure, making it easier to adapt to the desired application.

[0207] Regarding the requirements of the handpiece antenna, it is noteworthy that the handpiece antenna, due to the functional and structural features mentioned above, has very small dimensions (suitable for the usage conditions), can be easily manufactured, and provides adequate penetration capabilities.

[0208] In fact, due to the loop or segmented loop structure and the positioning of the distal handpiece portion around the insertion region of the insert assembly, the handpiece antenna has a uniform radiation lobe throughout its radiation region and generates a precisely stabilized and sufficiently strong electromagnetic field in the insertion region of the insert assembly.

[0209] The structure of the segmented ring antenna, with line sections connected by capacitors that compensate and / or cancel the inductance of the corresponding copper wire sections with their capacitance, avoids phase inversion of the current circulating in the coil and thus obtains a uniform and strong field in the area where the insert antenna intended to communicate with the handpiece antenna is located, especially in the center of the coil, finally allowing the unique insert identification device to be read and the operating and maintenance parameters of the insert to be written or read in the non-volatile memory.

[0210] The series configuration of capacitors connecting the line portions of the segmented ring antenna structure allows for precise tuning of the resonant frequency and allows relying on the total capacitance achieved by multiple capacitors ensuring precise resolution of the total capacitance value rather than a single component with rough tolerances and nominal values ​​given by the market.

[0211] Furthermore, the handpiece is provided with a communication line (handpiece antenna and associated RF signal feed means) that can enable proper impedance matching (essential for effective RF signal transmission and radiation) even in a small structure that does not allow the use of common impedance-matched RF transmission methods (e.g., coaxial cables and associated RF connectors). Such objective is achieved, for example, via an impedance-matching power supply network included in the segmented ring structure of the antenna and by a microstrip RF signal distribution circuit having the characteristics described above.

[0212] Those skilled in the art can make modifications and adaptations to the above-described embodiments of the insert assembly and medical system, or can replace functionally equivalent elements with other elements to meet conditional needs, without departing from the scope of protection of the attached claims. All features described above as belonging to possible embodiments may be implemented independently of the other embodiments described. [Explanation of symbols]

[0213] 1 Insert Assembly 2 Insert 3 Radio Frequency Identification Device 4 Medical Equipment Handpieces 5 Insert metal tongue 6 Ferromagnetic layer 7 Dielectric Layer 8 Insert Antenna 9 Insert antenna metal element 10 Identification chip 11 Transmitting and receiving equipment 12 Handpiece antenna 13 Chip housing 14. The substantially flat outer surface of the insert antenna metal element of the insert antenna 15 Inner surface of insert antenna metal element of insert antenna 16 Protruding tip part 17 Inner insulating layer, e.g. double-sided adhesive 18 Outer insulating layer, e.g. PVC or PET or polyamide 19 Biocompatible protective layers, e.g. paints or one- or multi-component epoxy compounds 20 Medical Devices 21 Control Elements 22 Handpiece Distal Part 23 Handpiece center part 24 Handpiece proximal part 25 Transducer, e.g., piezoelectric transducer 26 Ultrasonic generator or control unit 27 Threaded tongue for insert connection 28 Handpiece antenna connection element 29 LED 30 Handpiece Distal End 31 Light guide element 32 Concentrator 33 Handpiece Distal Cap 34 Connection cable 41 first end of handpiece antenna first segment 42 Second end of last segment of handpiece antenna 43 Handpiece antenna input impedance matching first electrical circuit network 44 Handpiece antenna - Antenna impedance matching second electrical circuit network 45 Handpiece Identification Device 50 Signal guide of radio frequency signal supply means (e.g., microstrip circuit) 51 First terminal of signal supply means 52 second terminal of signal supply means 53 Impedance matching circuit for microstrip printed circuit board 54 Microstrip Circuit RF Impedance Matching Network Smallest RF area connector with 55 pin connection 56 RF-DC decoupling network (or decoupler) 57 LED lighting circuit 58 Guide for DC Optical Signals 59 Handpiece antenna input RF impedance matching network 60 Coaxial connection cable between handpiece and control unit 61 50 Ohm RF Coaxial Connectors Smallest RF area connector with 65 pin connection 71 Identification chip power management element 71 72 Identification Chip Modulator / Demodulator Element 73 Identification chip controller 74 Identification chip non-volatile memory 101 Ultrasound System 102 Generator Means

Claims

1. A medical instrument handpiece assembly comprising a medical instrument handpiece (4), the medical instrument handpiece comprising a handpiece distal portion (22) adapted to receive, by insertion, an insert assembly (1), the insert assembly comprising a radio frequency identification device (3), an insert antenna (8) and an insert (2) adapted to interact with a part of a patient's body; wherein the medical instrument handpiece assembly further comprises a handpiece antenna (12) disposed in the handpiece distal portion (22) and a radio frequency signal providing means configured to provide the handpiece antenna (12) with a radio frequency signal suitable for transmission by the handpiece antenna (12); wherein the handpiece antenna (12) is configured to wirelessly communicate with the insert antenna (8) when the insert assembly is inserted into the handpiece (4) at an insertion region (R) provided in the handpiece distal portion (22); the handpiece antenna (12) is a loop antenna or a segmented ring antenna, the ring antenna comprising at least two handpiece antenna segments (S1, S2) electrically arranged in series, wherein a first end (41) of a first segment (S1) of the at least two handpiece antenna segments is electrically connected to a first terminal (51) of the radio frequency signal supply means and a second end (42) of a last segment (S2) of the at least two handpiece antenna segments is electrically connected to a second terminal (52) of the radio frequency signal supply means, so as to form a coil radiation structure around the insertion region (R) configured to generate an electromagnetic field in the insertion region (R) having a radio frequency dependent on a radio frequency signal; Each of the at least two handpiece antenna segments comprises a radiating metal element (S11, S21) characterized by a respective inductance (L) and electrically connected in series with a respective capacitive element (S12, S22) having a capacitance (C) so as to compensate the effect due to the inductance (L) of the radiating metal element on the current circulating in the coil of the handpiece antenna (12); Handpiece assemblies for medical devices.

2. 2. The handpiece assembly for a medical instrument according to claim 1, wherein the capacitance (C) of each of the capacitive elements (S12, S22) matches the characteristic impedance of the handpiece antenna (12) to a radio frequency generator provided in a control element (21) of the medical instrument (20) communicatively connected to the handpiece assembly (4).

3. The handpiece antenna (12) further comprises: an input impedance first matching electrical network (43) provided between the first and second terminals (51, 52) of the signal supply means and the first end of the first segment (41) and the second end of the last segment (42) of the handpiece antenna (12); an antenna impedance matching second electrical network (44) included in the segmented antenna ring and electrically connected in series between two segments (S1', S2') of the at least two handpiece antenna segments; 3. A handpiece assembly for a medical instrument according to claim 1 or 2, comprising:

4. 4. The medical instrument handpiece assembly of claim 3, wherein the input impedance first matching electrical network (43) comprises an inductance-capacitance circuit LC or a capacitance circuit.

5. 4. The medical instrument handpiece assembly of claim 3, wherein the antenna impedance matching second electrical network (44) comprises a resistance-capacitance circuit RC or a capacitance circuit configured to match the antenna impedance to a desired impedance value and adapted to optimize transmission of the radio frequency signal.

6. The radiating metal elements (S11, S21) of the segmented ring antenna can be modeled by an equivalent electric circuit with an inductance (L) and a resistance (R), where the inductance is in the range between 2 nH and 30 nH; 6. A handpiece assembly for a medical instrument according to any one of claims 1 to 5, wherein the capacitive element (S12, S22) is a capacitor having a capacitance C lying in the range between 1 pF and 12 pF.

7. 7. A handpiece assembly for a medical instrument according to claim 1, wherein the inductance value (L) of the radiating metal element is different for each segment, and the capacitance value (C) of the capacitance element is different for each segment according to the inductance value (L) of the respective segment.

8. 7. A handpiece assembly for a medical instrument according to claim 1, wherein the inductance values ​​(L) of the radiating metal elements are equal to each other in different antenna segments, and the capacitance values ​​(C) of the capacitive elements are equal to each other in different antenna segments.

9. 9. A medical instrument handpiece assembly according to any one of claims 1 to 8, wherein the handpiece antenna (12) is configured to operate in a frequency range in the UHF RFID band between 860 MHz and 960 MHz.

10. 10. A handpiece assembly for a medical instrument according to claim 1, further comprising a handpiece identification device (45) suitable for wireless or wired communication with the handpiece antenna (12), the handpiece identification device (45) being suitable for providing information for identifying the handpiece antenna (12) and / or information regarding the operating state and / or operating frequency of the handpiece antenna (12).

11. Here, the radio frequency signal supply means is a signal guide (50) comprising a microstrip circuit configured to guide a radio frequency supply signal from a connection cable (34) between the handpiece (4) and the control element (21) of the medical device (20) to the handpiece antenna (12); a handpiece antenna connection element (28) connected to the signal guide and to the handpiece antenna (12) and comprising a first terminal (51) and a second terminal (52) of a radio frequency signal supply means; 11. A medical instrument handpiece assembly according to claim 1, comprising:

12. 12. The medical instrument handpiece assembly of claim 11, wherein the microstrip circuit is a controlled impedance circuit comprising metal tracks and having a thickness comprised between 0.2 mm and 1.0 mm.

13. 13. A handpiece assembly for a medical instrument according to any one of claims 1 to 12, wherein the coil radiating structure of the handpiece antenna has a diameter of less than 30 mm so as to be accommodated within an inner wall of the handpiece distal portion (22).

14. 14. A handpiece assembly for a medical instrument according to any one of claims 1 to 13, wherein the handpiece antenna (12) is connected to the handpiece distal portion (22) in a separable manner.

15. 15. A handpiece assembly for a medical instrument according to any one of claims 1 to 14, wherein the handpiece antenna (12) is fixedly or detachably connected to the central handpiece part (23).

16. wherein the handpiece antenna (12) is formed from a flexible-rigid multi-layer T-shaped or G-shaped printed circuit with a flexible printed circuit portion extending from a rigid printed circuit component; A handpiece assembly for a medical device as described in any one of claims 1 to 15, wherein when the flexible rigid multilayer printed circuit is positioned inside the distal portion (22) of the handpiece (12), the upper part of the T or G shape is wrapped around a cone provided in the handpiece distal portion (22) so that the edges of the upper part of the T or G shape overlap and form electrical contact, forming a loop or segmented ring of the handpiece antenna (12).

17. A medical instrument (20) comprising a control element (21), a handpiece assembly for a medical instrument according to any one of claims 1 to 16, and an insert assembly (1) comprising a radio frequency identification device (3), an insert antenna (8) and an insert (2) adapted to interact with a part of a patient's body, the insert assembly (1) is separably, communicatively and mechanically connected to a handpiece (4) of the handpiece assembly; The medical device, wherein the insert antenna (8) and the handpiece antenna (12) are configured to wirelessly communicate with each other at radio frequencies.

18. 18. The medical device of claim 17, wherein when the insert assembly (1) is connected to the handpiece (4l), the insert antenna (8) is configured to be positioned in the vicinity of the handpiece antenna (12) in an insertion region (R) in which a radio frequency electromagnetic field generated by the handpiece antenna (12) is present in a radiated state.

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