DESCRIPTION

Field of application

The present invention regards an orthodontic prosthesis and a method for archiving information in an orthodontic prosthesis, according to the preamble of the respective independent claims.

The present prosthesis can be of fixed or movable type, and preferably of fixed type, i.e. intended to be mechanically associated with an implant or with a portion of a natural tooth, e.g. by means of cementation. More in detail, the prosthesis, object of the present invention, can be constituted by a crown, and hence intended to be anchored on a tooth or on a residual root thereof, by a bridge and therefore intended to form a structure resting on multiple teeth adjacent to the missing teeth to be restored, or by a prosthesis on implant and hence intended to form a structure to be applied on implants inserted in the bone.

The present invention is therefore inserted in the field of production of orthodontic devices, i.e. it is intended to be employed in that branch of orthodontics termed implantology which is concerned with the partial or complete replacement of dental elements with artificial analogous dental elements.

State of the art

The orthodontic prostheses are medical devices, i.e. they are artificial teeth or more often artificial parts of teeth, which are used for reconstructing a part of the natural tooth that has been removed, protecting the tooth from complete destruction, or for completely replacing one or more teeth, in this case being applied on implants inserted in the bone. The orthodontic prostheses are usually shaped as single or multiple shells, respectively in the case they affect a single tooth (crowns or capsules) or in the case they affect multiple teeth (bridges).

Prostheses are therefore generally intended to be mounted both on natural teeth - and in this case they are fixed to projecting teeth portions, or by means of endodontic posts, to the root of the tooth or teeth - and on projecting portions of artificial implants, such as screws.

The technologies for obtaining prostheses are in continuous evolution, also due to the continuous discovery of new materials capable of associating high mechanical strength characteristics with improved aesthetic characteristics, simultaneously allowing the obtainment of the functional recovery of the tooth and the recovery of its natural aesthetic appearance.

This has led to a considerable diversification and proliferation of prosthetic manufactured items introduced on the market, with the consequent problem for the professional dentist called to operate on an already-exiting prosthesis that was made by others: often, such professional will have to understand the prosthesis type or the materials used, the type of mechanical connection or cementation to the core, to the column or abutment or the tooth or of the implant, in order to be able to perform the operation as best as possible and in a manner entirely compatible with the pre-existing implant or the prosthesis.

More in detail, in order to perform an operation on a pre-existing prosthesis, it is necessary to understand the characteristics of the core or abutment, in order to achieve a correct prosthetic interface connection with the implant, or a correct prosthetic interface connection with the core of the tooth. The information on the prosthesis and on the implant already installed in the mouth of the patient are also useful for the selection of the transfer to be screwed to the implant, to be used during the impression step or for establishing the position of the implant itself and allowing the laboratory to correctly achieve the prosthetic implant work.

The information regarding the preceding prostheses is even more important in the case of complex structures on implants, in the case of screwed crowns, or in the case of screwed structures.

As is known, as a function of the costs, of the functional and aesthetic result that one wishes to obtain, the prostheses are available in numerous materials, and in particular they are available made of metal, metal-ceramic (porcelain) or only made of ceramic materials.

Porcelain for the dental field is usually composed of a mixture of feldspar, quartz, boron oxides and a low percentage of other oxides. Porcelain for the dental field usually makes the prosthesis, starting from porcelain powder mixed with water placed to cover a metallic nut coated with glue layers and with a platinum sheet; once the powders have been compacted, the firing in the furnace occurs, during which the capsule sinters or a melted glass layer is formed that is inserted between the porcelain particles, filling the voids. Finally, the enameling of the surface of the capsule occurs in order to obtain a shiny, regular and impermeable surface. In order to make up for the poor tensile strength and fragility of this ceramic manufactured item, a support structure made of metal alloy is usually used.

The achievement of the metal alloy structure is obtained with high-melting-point alloys, stellites and alloys with high palladium content.

In particular, the following are available in dentistry: alloys made of metal of noble type, such as gold alloys via melting, alloys via welding or filling, alloys for direct reconstructions, alloys for metal-ceramic techniques and non-noble alloys such as stainless steels, stellite alloys.

In particular, the hard noble metal alloys contain, with respect to the light and medium alloys, palladium and platinum in greater portions in order to confer high mechanical properties to the alloy, allowing a use thereof in the construction of crowns, bridges and inlays. The extra-hard metal alloys contain platinum and palladium in concentrations up to 12% and are intended to be employed for the construction of circular bridge prostheses, crowns and inlays.

Alloys are also known for metal-ceramic techniques, which must allow the chemical bonding with the porcelain structure. They must have high mechanical characteristics, in particular high mechanical tensile and torsional strength and a high melting point. Among these alloys, there are those with gold-platinum-palladium base with the addition of silver, indium and tin, palladium-based alloys with the addition of tin, gallium and gold in small concentrations; non-noble alloys for metal-ceramic which use different percentages of chromium, cobalt, molybdenum, tungsten, nickel and titanium.

Other ceramic materials are known which do not require the support of a metallic structure, like lithium disilicate, which is indicated for the obtainment of single monolithic repairs, zirconium oxide or other innovative ceramic materials that provide highly aesthetic results and with respect to other simpler ceramics have a considerable greater strength.

Known prosthetic materials are also calcinable plastic and PMMA, the latter above all employed for movable and temporary prostheses.

The above-indicated presence of a multiplicity of prosthetic manufactured items and materials for the obtainment thereof has brought the dentistry field to face an increasingly serious problem, currently still unresolved, regarding the correct identification of the characteristics of the prosthesis installed in the mouth of the patient, in order to allow the doctor to intervene in the best possible manner in a pre-existing situation by employing modern prosthesis preparation techniques. In particular, once the prostheses have been installed in the mouth of the patient, the following are no longer understood: the materials used, their size characteristics, possible threads or fixing systems employed for the connection to the abutment of the implant or core of the tooth.

Usually, such technique for preparing the prosthesis starts from taking impressions, which are usually delivered to specialized laboratories for the construction of the prosthesis.

The metallic support structure is then usually obtained, on which the porcelain will be fired, and the material of the support structure depends on the type of prosthesis. Or the complete prosthesis is directly obtained, if it is made only of ceramic material, as explained above.

In recent years, the computer-assisted obtainment of fixed prostheses with CAD/CAM technology has assumed great importance.

For such purpose, from the impression, a model is usually obtained, for example made of plaster, which is subjected to scanning.

Then there is the obtainment of the design of the prosthetic repair through dedicated CAD software and the design file (e.g. in standard open format STL) thus obtained is employed by a CAD-CAM milling laboratory which achieves the support structure with milling techniques for an accurate quality of the structure.

The dental technician laboratory therefore checks that the modeling is anatomically perfect in order to reconstruct the affected tooth or teeth, in the manner more similar to what occurs naturally, with points of contact adapted to ensure the uniform distribution of the mastication load over the entire arch, adapted to ensure the correct occlusion for a suitable functionality of the prosthesis with the correct size of the interdental and interstitial spaces and with a correct reconstruction of the axial curvature and rounding of the cusps. Known from the patent EP - A 2022443 is an implant with an electronic identification device arranged therein, in which it is possible to store information and collect such information in an easy manner by bringing a reader device close thereto. Such solution assists the doctor in understanding the obtained implant but is not susceptible of informing him/her on the prosthesis model. In addition, such patent does not provide, in particular does not provide the dental technician, a simple method for the insertion and preservation of the electronic identification device in the implant.

The patent US 201 1/136076 describes an orthodontic prosthesis comprising a dental crown provided with an internal surface intended to be fixed to the core of a tooth, and an external surface intended to be arranged in the oral cavity of the mouth in order to allow the prosthesis to perform the mastication functions. In addition, the orthodontic prosthesis comprises an electronic device fixed to the internal surface of the dental crown in order to be abutted against the core of the tooth, and adapted to store information relative to the person with the dental prosthesis implanted, such as name, date of birth, blood group, credit card codes etc.

The patent WO 02/13719 describes a denture provided with a gum support body, intended to be attached to the maxilla or mandible of a person, and with multiple artificial teeth fixed to the gum support body and adapted to constitute or complete the corresponding dental arch of the person who uses the denture. The denture also comprises an electronic signaling device fixed to the gum support body and adapted to emit an identification signal, which is susceptible of being detected by a receiver in order to trace the denture in case it is lost.

The orthodontic prosthesis described in US 201 1/136076 and the denture described in WO 02/13719 are not adapted for storing information relative to the prosthesis or to the denture themselves and providing such information to the dental technician. In addition, the above-described orthodontic prosthesis and the denture of known type do not allow a good reading of the information stored in the corresponding electronic device or of the signals sent by the latter.

Presentation of the invention

In this situation, the problem underlying the present invention is therefore that of overcoming the drawbacks and the limits manifested by the abovementioned solutions of known type, by providing an orthodontic prosthesis whose characteristics are recognizable even some time after its installation.

Another object of the present finding is to provide an orthodontic prosthesis which is susceptible of providing, at any moment, information relative to its characteristics, especially size and structure, relative to the obtainment materials, relative to the system of connection to the core of a natural tooth or an implant, as well as possibly also the information relative to the characteristics of the implant on which the orthodontic prosthesis is fixed.

Another object of the present finding is to provide an orthodontic prosthesis which allows easily executing dental implantology operations by providing the dental surgeon with its technical characteristics in a facilitated manner.

Another object of the present finding is to provide an orthodontic prosthesis which is entirely safe for the patient.

A further object of the present finding is to provide an orthodontic prosthesis that is structurally inexpensive to make, simple to use and entirely reliable in operation.

A further object of the present finding is to provide an orthodontic prosthesis which provides the aforesaid information in a quick and rapid manner.

Another object of the present finding is to provide a method for archiving information in an orthodontic prosthesis, which is simple to obtain and allows an easy reading of the archived information.

Brief description of the drawings

The technical characteristics of the invention, according to the aforesaid objects, can be found in the contents of the below-reported claims and the advantages thereof will be clearer in the following detailed description, made with reference to the enclosed drawings, which represent several merely exemplifying and non-limiting embodiments of the invention, in which:

- figure 1A shows a section view of an orthodontic prosthesis mounted on the core of an implant according to a first embodiment of the present invention;

- figure IB shows a section view of an orthodontic prosthesis mounted on the core of an implant according to a second embodiment of the present invention;

- figures 2A-2D show the main steps of a method for archiving information in an orthodontic prosthesis in accordance with a first embodiment of the method that is the object of the present invention;

- figures 3A-3D show the main steps of a method for archiving information in an orthodontic prosthesis in accordance with a second embodiment of the method that is the object of the present invention.

Detailed description

In accordance with the figures of the enclosed drawings, reference number 1 overall indicates the orthodontic prosthesis that is the object of the present invention.

The aforesaid orthodontic prosthesis 1 is intended to be employed, in a per se entirely conventional manner, in the field of dental implantology for the replacement of teeth or parts of teeth with artificial analogous elements to be positioned on cores or abutments of natural teeth or artificial implants, as already more specifically indicated above.

Hereinbelow, with the term orthodontic prosthesis 1 , it must be intended any one manufactured artificial tooth item that is used for reconstructing a part of a natural tooth or for completely replacing one or more teeth, given that it is applied on at least one projecting part of a natural tooth and/or on at least one projecting part of an implant. Hereinbelow with the term core 20, it must be intended that projecting part of natural tooth or implant intended to be mechanically coupled in a rigid manner, usually fixed with the orthodontic prosthesis 1.

The prosthesis 1 is per se made of various possible materials and via various production techniques in the form of a shaped body 2, with the external surface that follows the morphology of the tooth or the teeth to be reconstructed with the prosthesis.

According to the idea underlying the present invention the aforesaid shaped body 2 is provided with a seat 3 delimited by an opening 3A, by a bottom 3B and by a peripheral surface 3C, which is extended from the bottom 3B up to the edge of the opening 3A. The orthodontic prosthesis 1 according to the invention also comprises an electronic identification device 4, which is inserted in the seat 3 below the opening 3A. A sealing layer 5 is then provided that is fixed in the seat 3, above the electronic identification device 4, to close the opening 3 A in order to retain the same electronic identification device firmly anchored to the seat 3; thus, such device is prevented from being contaminated by liquids or solid particles, such as food particles, once the prosthesis 1 is installed in the mouth of the patient.

The sealing layer 5 can be a resin or a cement normally employed in dentistry for the occlusion of openings in the teeth.

The electronic identification device 4 is advantageously constituted by a transponder device or tag of RFID (Radio Frequency Identification) type characterized by the use of radiofrequency for transferring data to a reading device (reader) which requires the information (of type per se known to the man skilled in the art and hence not illustrated and described in detail) and which queries the transponder 4 by sending radiofrequency waves. The reading device and the transponder 4 are able to send and receive data by exploiting an inductive coupling. The transponder 4 comprises an electronic circuit with at least one permanent memory in which at least one information relative to the prosthesis is recorded and preserved and one transmission unit such as an antenna for transmitting the aforesaid at least one information. The information of the prosthesis can regard the date of installation, the prosthesis model, the materials for obtaining the prosthesis, the type of connection to the tooth or to the implant, size measurements, characteristics of the implant or of the tooth, mechanical characteristics of the prosthesis, the dentist office that performed the operation, clinical notes of the patient, etc. The memory is in particular of the type adapted both for reading and writing.

The transponder 4 is also advantageously of passive type, i.e. without autonomous power supply, and has an inductance associated therewith that transforms the electromagnetic waves of the reader device into electrical energy susceptible of power supplying the memory so that, through an antenna, it emits a signal in electromagnetic wave form containing the information archived in the memory. In the case of passive transponder, the antenna also performs the function of rectenna, i.e. rectifying at least part of the energy of the radiofrequency waves received by the reader device, in order to power supply the circuit of the transponder 4.

Advantageously, the electronic identification device 4 comprises a cover case 6, in particular made of plastic, shaped in a manner substantially corresponding to the seat 3 in order to be precisely housed therein.

The case 6 has a cavity 7 susceptible of receiving the actual electronic part of the transponder 4.

Between the peripheral surface 3C of the seat 3 and the side surface 6C of the cover case 6, a drain 8 is obtained for allowing the easy precise insertion of the electronic identification device 4 in the seat 3, without such insertion being obstructed by a compression of the air contained in the seat 3 during insertion of the device 4 itself.

In accordance with the embodiment of the enclosed figures, the drain 8 is obtained in groove form along the thickness of the side surface 6C of the cover case 6, though in an entirely equivalent manner it can be obtained on the peripheral surface 3C of the seat 3. The shaped body 2 of the prosthesis 1 is provided with an external surface 2A formed by a mastication surface 2 A', susceptible of being directed towards the teeth of the opposite dental arch, and by a perimeter surface 2 A" intended to be extended from the mastication surface 2A' up to the neck G of the gum.

The seat 3 is obtained on the external perimeter surface 2A" of the shaped body 2, before the installation of the prosthesis 1, such that it can be easily obtained with complete maneuvering freedom in the position most suitable for the operation, as indicated in figure 1 A. For example, it can be placed in a lingual zone that is not very visible, in order to prevent even the most minimal blemish due to the installation of the prosthesis 1.

The orthodontic prosthesis 1 can comprise, in a per se known manner, a support structure 10 with shell form, in particular made of metal or metal alloy, defining an external surface 10A and an internal surface 10B and a coating 100, in particular made of ceramic material, fixed on the external surface 10A of the support structure 10 and provided with an internal surface 2B and with the abovementioned external surface 2A of the shaped body 2.

The external 2A, 10A and internal 2B, 10B surface respectively of the coating 100 and of the support structure 10 will in turn be formed by a mastication surface and by a perimeter surface placed parallel to each other as well as placed at the abovementioned external mastication 2 A' and perimeter 2A" surfaces of the shaped body 2. In particular, the shaped body 2 of the orthodontic prosthesis 1 comprises the aforesaid support structure 10 and the aforesaid coating 100.

The seat 3 is advantageously obtained starting from the internal surface 10B of said support structure 10 up to reaching the coating 100, as indicated in figure IB. In this manner, it is possible to completely go beyond, with the depth of the seat 3, the metal layer of the support structure 10 by exposing the electronic identification device 4 to the reader with only the porcelain layer of the coating 100 interposed, which per se is not susceptible of screening the input and output electromagnetic waves with respect to the device 4.

Advantageously, indeed even if the electronic identification device 4 is of RFID radiofrequency type extended on a main extension plane P with reading direction Y orthogonal to such plane P, due to the presence of an induction winding provided with a preferred direction of linking the electromagnetic waves, it can be read at least from both senses of the direction Y orthogonal to such plane P. Therefore, the device 4, once inserted in the seat 3 obtained in the internal surface 10B of the support structure 10, with the main extension plane P parallel to the internal surface 10B of the support structure 100, can then be queried by the reader in a position facing thereto at the external surface 2 A of the coating 100.

Also forming the object of the present invention is a method for archiving information in an orthodontic prosthesis 1 of the above-described type.

Hereinbelow, for the sake of description simplicity reference will be made to the same nomenclature introduced up to now, even if it must be intended that the present method can also be used in association with an orthodontic prosthesis with different characteristics with respect to those considered above.

The method, object of the present invention, starts by providing an orthodontic prosthesis 1.

There is then the obtainment, on a surface of the shaped body 2 of the aforesaid orthodontic prosthesis 1, of a shaped seat 3, delimited by an opening 3 A, by a bottom 3B and by a peripheral surface 3C, which is extended starting from the bottom 3B up to the aforesaid opening 3A.

Advantageously, the aforesaid step for obtaining seat 3 provides for obtaining seat 3 itself on the external perimeter surface 2A" of the shaped body 2 of the orthodontic prosthesis 1.

According to the idea underlying the present invention, the arrangement of a handpiece 9 is therefore provided, bearing the electronic identification device 4 mechanically associated at one end 9A; such device 4 is shaped in a manner substantially corresponding to the seat 3.

By acting on the handpiece 9 with a manual or automatic operation, i.e. by means of the grasping of the handpiece 9 by an operator or a robot, the precise insertion is actuated of the electronic identification device 4 in the seat 3 preformed in the shaped body 2 of the orthodontic prosthesis 1.

Advantageously, in the aforesaid insertion step, the electronic identification device 4 is inserted in the seat 3 with its own main extension plane P parallel to the internal surface 10B of the support structure 10 of the orthodontic prosthesis 1, in order to allow the electronic identification device 4 to be queried by a reader in a position facing thereto at the external surface 2A of the coating 100 of the orthodontic prosthesis 1, as discussed in detail above.

After the aforesaid insertion of the device 4 in the seat 3, there is the separation of the electronic identification device 4 from the end 9A of the handpiece 9 with its consequent release inside the seat 3. Finally, there is advantageously a step for closing the opening 3A of the seat 3 with a sealing layer 5 fixed in the seat 3, above the electronic identification device 4 in order to retain the latter firmly fixed inside the seat 3 without the device 4 being reached by liquids, food particles or other material that can compromise the functioning thereof. Preferably, the electronic identification device 4 comprises a cover case 6 made integrally with the handpiece 9 and fixed thereto by means of a neck portion 90 of the handpiece 9, of thinned form.

The aforesaid step for separating the electronic identification device 4 from the end 9A of the handpiece 9 is preferably obtained through breakage of the neck portion 90. The breakage is advantageously obtained by tilting the handpiece 9 with respect to the depth extension axis of the seat 3 indicated with Z in figures 2A-2D. Indeed, due to its precise positioning in the seat 3, the device 4 is not susceptible of rotating inside the seat 3 itself such that when bending handpiece 9, it remains firmly in the position coplanar to the seat 3 and determines the stretching of the fibers of the neck portion 90 of the handpiece 9 until their breakage and liberation of the device 4 in the seat 3 itself.

Otherwise, in accordance with another embodiment of the method, object of the present invention, the electronic identification device 4 is connected to the end 9A of the handpiece 9 by means of removable coupling means 1 1. Consequently, the step for separating the electronic identification device 4 from the end 9A of the handpiece 9 is carried out through the separation of the removable coupling means 1 1. The latter can be obtained for example by means of a simple precise fitting between corresponding forms of the handpiece 9 and of the case 6 of the device 4, in particular of male/female type, by exploiting the elasticity of the plastic material with which the same handpiece 9 and the same case 6 are obtained. In accordance with the embodiment reported in the figures 3B and 3C, the end 9A of the handpiece 9 is shaped with an opening 91 in which a protuberance 92 is removably and fittingly inserted, such protuberance 92 obtained on one face of the case 6 of the electronic identification device 4.

Advantageously, the electronic identification device 4 can be initially associated with a plastic support 200 of the same material as the case 6, from which the latter will be separated by breaking a thinned connection portion 201, as schematically indicated in figure 3B. Therefore, before the insertion step, a step will be provided for separating the electronic identification device 4 from the plastic support 200.

Furthermore during the preparation of the components, a step is advantageously provided for associating the actual electronic part of the transponder 4 with the relative fixed cases 6 aligned on supports 200, by means of the insertion of the aforesaid electronic parts in the provided cavities 7 of the cases 6.

The invention thus conceived therefore attains the pre-established objects