Bleaching device employing electro-optical and chemical means, which is intended, in particular, for use in the medical and dental field

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DESCRIPTION

Bleaching device using electro-optical and chemical means, particularly in the medical and dental field.

Field of the invention

The present invention has for its object a device for bleaching the body ensuring its structural integrity, applicable in particular in the industrial fields for fabrics, the medical field for nails and hair and the dental field for teeth, comprising a generator of an electrophoretic field that transports directly, or by means of an electrically active product, the active bleaching molecules towards their targets, the products that are degraded or not responsible for the coloration towards the outside and possibly one or some active molecules capable of reconstituting the body that has suffered the action of the bleaching products in the body, thus reducing any short or medium-term degradation that could cause the chemical applications of the active products and the decrease of the coloring molecules and that eventually also comprise a thermal and / or photonic source that activates or accelerates the activation of the products applied for the bleaching, all under the control of an electrical or colorimetric sensor.

Whitening a tooth, or more precisely giving it its natural color of origin, specific to the patient, is an action usually practiced in dental offices for more than 100 years and very important for the psychological balance of patients.

A very good explanation of this aesthetic action has been given, and reference is made in the technique: the special supplement of the JADA (Journal American Dental Assoc.) Of April 1997, n ° 128 (supplement) pages S1 to S64 entitled “non restorative treatment of discolored teeth, reports for an international symposium ”and summarizing the conference in Chapel Hill, North Carolina, September 25 and 26, 1996. An update can be found in the CRA (Clinical Research Associates Newsletter) Volume 24, published on April 4, 2000, or even more recently in "Incidence of tooth sensitivity after home whitening treatment" by Jorgensen et al., JADA, August 2002, Vol. 133 pages 1076-1082.

It stands out from these works that there are currently three major bleaching methods used in dental and medical offices:

- a mechanical method, which consists of combining abrasive polishing pastes with the descaling of the teeth by mechanical means (manual and ultrasound),

- a chemical method, which generally follows the previous one, and which consists of applying a product to the tooth capable of removing superficial deposits, such as those caused by tea or coffee. These products are frequently based on carboxide or peroxide, in very low concentration and that can be used by the patient at home,

- a more invasive chemical method that has higher concentrations of peroxide-based product, which frequently requires the intervention of the dental surgeon, taking into account the risks incurred by the patient if they do not apply their therapy with the rules of dental and medical technique , and that allows to reduce the coloration of the teeth inside the dental organ itself. This method was recently modified and its action reduced so that it can be used by the patient himself at home (home kit) under the protection of a regular medical check-up.

Unfortunately and very quickly, both doctors and their patients have realized that:

- the application time was very long and required immobilization of the patient for more than 5 minutes per tooth or 20 minutes on each side of the alveolar arch,

- therefore, the cost of the intervention was burdensome and prohibitive!

It is for this reason that products have been developed that react more quickly, being activated by light or heat. This method makes it possible to reduce the time spent on the medical bleaching action by a quarter.

Based on these promising results, a number of products called photosensitive that combine perborate and hydrogen peroxide or camphorquinone-activated peroxide carbamide, photosensitive for its part between 400 and 500 nm. These products are the result of techniques originally developed and presented by CORCORAN and ZILLICH (1974) and by RENNEBOOG (1989). These studies highlight the role of heat and radiation contributed by halogen lamps in activating bleaching products.

Thus, there are numerous bleaching products on the market today that can be used directly by the patient at home or applied in a higher concentration by dentists. These products act directly or after activation by light or heat. The vast majority of them use hydrogen peroxide as the base formula at approximately 35%, as had first been described by HALON in 1884.

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In order to further activate the reaction and to halve the already considerably reduced time, it has been requested that even more powerful lamps be developed, and it is for this purpose that the plasma lamp with xenon arc “Apollo 95^AND", Patents FR 2,773,986 and FR 2,782,000, which included a" bleaching "function and which involved an action of the order of 30 seconds on the product placed in contact with the tooth. This product is often in the form of a gel, held in a transparent ribbed device. A typical example has long been sold under the name "Apollo secret whitening kit" (DMDS Corp. Los Angeles, USA).

Obviously, the results obtained have been spectacular, and many manufacturers have followed this technology. However, this procedure, although it considerably shortened the time, suffered from numerous limitations.

Indeed, it has been shown that:

- with some product the action of the lamp, therefore its effectiveness, was due not only to photonic but also thermal emissions and under these two effects these products were activated,

- as the cost of these lamps is very high, the treatment was relatively expensive,

- as these methods require high concentrations of peroxide, they prevented their domestic use by the patient,

- the thermal rise observed in the tooth was disproportionate to the activation of the product and could even be dangerous if the action was very prolonged,

- it was impossible to correctly control the thermal value at the level of the tooth with the risk of causing important disorders in the health of the dental pulp. In addition, the movement of the hand itself could cause variations in the location of the point of light or thermal impact,

- replacing the light emitted by high thermal emission lamps such as xenon arc lamps or halogen lamps by so-called cold light lamps such as those described in documents FR 2.805.148 and FR 2.818.892, the thermal effect was suppressed, which allowed the operator to safely increase his time of action to activate the photosensitive products, but at the same time it forced him again to a prolonged exposure due to the suppression of the heat source,

- if a scattered light is used over the entire alveolar arc (for example in the form of a luminous fluted device) the time is again reduced, but not more than when using high powers,

- the doses applied for the treatment both in the dentist's office (30% peroxide) and at the patient's home (8-10% peroxide) are extremely high in relation to the intended objective, and explain the observed side effects (dental pain before the cold),

- there are numerous recurrences, because the molecules responsible for the coloration are modified, even fragmented, but are never really evacuated from the site. The fact that they remain allows the recombination of initial chemical bonds, which explains the need for successive treatments in increasingly shorter periods,

- Finally, the aggressive action of peroxide in contact with the gingiva always forces both the doctor and the patient to take numerous precautions to avoid burns during and after treatment.

In addition, at no time had a fundamental problem been solved that has justified the placing under surveillance of bleaching products and in particular peroxide by all safety commissions in the field of health, from the EC to the FDA: What is the degree of degradation of the tooth under the effect of these products, which are applied massively in high doses, or slowly in a stable manner in the patient's home? Are post-operative pain the result of tooth decay, as has been stated by many authors? How to correct some significant decalcifications observed in patients after wrongly applied treatments?

In short, if it is possible through known techniques to allow a faster action of the bleaching products, there is no method that allows controlling, at low cost, the activation of the bleaching chemicals and correcting tooth degradation. resulting from its effects.

Even more serious is the future of the molecules responsible for coloring. Indeed, after a treatment based essentially on the division of large colored molecules into smaller molecules, the residue of this reaction remains, with the active agent, inside the dental organ, slyly continuing its effect and significantly limiting the penetration of the tooth. fluorine or calcium.

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In addition to the consequences of this steric hindrance, it is observed that the arrival at the intradental site of action of the bleaching molecule is carried out by pure passive permeability that undoubtedly explains its poor penetration, the time used to allow its action, the absence of control possible of the reaction by the operator but also a total ignorance of its real concentration in the zone of action, that is to say about the molecules responsible for the coloration in the dental tissue.

Finally, the absence of an objective and inexpensive starting reference and monitoring of the evolution of tooth whitening makes its estimation perfectly subjective.

Document WO-A-98/06456 shows a device according to the preamble of claim 1.

The present invention aims to solve the aforementioned drawbacks, proposing a complete bleaching set composed of an electrochemical system, particularly applicable in the dental and medical fields, which allows, thanks to the creation of an electrophoretic field, a deep penetration , fast and directive of bleaching agents, its removal under the same conditions accompanied by the molecules responsible for the coloration and an effective and controlled penetration of the stabilizing agents of the apatite crystals, which constitute the base of the tooth, such as fluorine, but also thanks to its optical system to light base allow the activation of photosensitive whitening products reducing the effect of heat increasing the photonic effect thanks to a selection of the wavelength, which is situated at approximately 400-500 nm and, finally, thanks to an electro-optical set, the control of the evolution of the coloration by objective methods based on spectrocolorimetry.

The present invention aims to solve these problems by proposing an adjustable, inexpensive and usable solution both in a dental office and, in a simplified way, in the patient's home.

In particular, it solves numerous problems mentioned above, since:

- By the applied means, the device offers a natural energy source for activating the components responsible for bleaching, which is the ohm effect due to the passage of electrophoretic current in a gel, the complement provided by electrical heat sources or even the addition of a photon emission (LED),

- the cost of said system, which makes it possible to avoid the use of lamps, is extremely small, since an electrophoretic source is nothing more than an electrical supply. This cost becomes very small if the same power is used for an electric toothbrush and the device of the present invention,

- the electrophoretic energy control means, provided by a simple power supply similar to a power supply from an electric toothbrush, allows its use at the patient's home. Modem communication allows the dentist to follow the evolution of the treatment over the Internet,

- the thermal rise caused by the device enables the bleaching molecules to be activated before moving them towards the center of the tooth,

- the thermal value can be fully controllable thanks to a feedback device independent of the operator,

- if LEDs are used, it is not necessary to increase the time in relation to lamps with high thermal emission, since the natural thermal effect that accompanies any electrophoretic current is added to the photonic effect,

- the LEDs are tiny, and can be placed against the surgical site, avoiding the use of a lamp with optical fibers, which considerably reduces the cost of the device,

- the doses applied for the treatment both in the dentist's office and at home are very low for an identical effect and much higher than equal doses, since the active molecules are provided on the colored site, and the molecules responsible for this coloring are evacuated by electrophoretic currents,

- the evacuation of the colored molecules out of the tooth reduces recurrences,

- the reduction of the doses for a similar effect allows to reduce the secondary or undesirable effects, such as the caustic action on the gum.

To this end, the present invention refers to a device for activating reactive molecules responsible for the whitening and selective amplification of their movements towards the interior of the tooth, of the reverse movement of the products resulting from their internal action and of their replacement, by a movement also captured by the device, of the molecules that stabilize and reinforce the structure of the tooth, all under the control of a system for measuring its effectiveness.

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Thus, the device according to the invention is defined in claim 1. Claims 2 to 17 refer to preferred embodiments of the device according to the invention. The device comprises:

- a central unit that allows controlling the parameters that define thermal dynamics (such as intensity, variation, speed or acceleration), photon dynamics (such as power and wavelength), electrophoretic dynamics (such as intensity , the power, the frequency, the profile and the modulation, but also a feedback control system of the action in progress or the one obtained), the time, the storage, the reading and transmission of data on different media,

- an extra-oral set, essentially electro-opto-digital included or not in the central unit and containing:

- an electronic system that creates a polarization field that makes it possible to obtain an electric, electromagnetic or electrophoretic field between the gel deposited on the tooth and the interior of the tooth, and whose function is to activate and direct a direct ionic flow.

By direct action it is understood that the electric field that has been created acts directly on the present (and global) charges of the molecules that are of interest in bleaching. In this way, an electric or magnetic field will be obtained that acts directly on the positive or negative charges of the active molecules, such as the peroxide responsible for bleaching, transporting them to the interior of the tooth so that they penetrate it quickly and deeply. A reverse movement, simultaneous or not, of the whole or degraded coloring molecules will also be obtained by the bleaching agents, so that they do not remain in the enamel and are not at risk of recombining. Finally, a last movement, combined or not with the bleaching agents, will be obtained of the restorative ions of the tooth towards the interior of the enamel (for example the negative ion fluorine in doses of 1.1 ppm).

This action can be indirect if the molecules to be displaced are not electrically active. In this case, it is no longer the active molecules (peroxide, dye and fluorine) that are transported by the electric field, but a complementary product sensitive to the electric field and capable, due to its electrical characteristics, of being transported by this field, and by its chemical characteristics, to be fixed on the active molecules, or simply to transport them without a chemical union but by passive transport, like any fluid in motion and capable of transporting particles.

It must be specified that the incorporation of stabilizing and reinforcing ions of the tooth fills any gaps that result from the action of bleaching.

According to an additional characteristic of the device according to the invention, it comprises a device that activates the photosensitive products thanks to an LED, halogen or arc light system, associated with a complementary thermal system in the case in which cold light is used ( LED) and / or if the active products are temperature sensitive. The transport of the necessary energy to the area to be bleached is carried out with the help of optical fiber in the case of light energy, fluid in the case of thermal energy and threads in the case of electrical energy.

According to another additional characteristic of the device according to the invention, it comprises a spectrum or colorimetric sensor capable of storing and indicating, by comparative principle, the specific adjustments and changes in the coloration of the teeth. This elemental and inexpensive spectrocolorimeter makes it possible to measure before and after the treatment the progressive change in the coloration of the gel that is loaded with degraded products and / or of the treated tooth that is released.

The device also includes an endobucal assembly that contains:

- a corrugated device, generally transparent, capable of containing bleaching products such as peroxide solutions, peroxide-degraded coloring products, and fluorinated gels (for example). These ribbed devices can be standard or individual for each patient and / or each type of product, in particular, during indirect action,

- possibly a grooved device included in the first or adaptable on it, which carries the light sources (LED for example) or which conducts the light (halogen or plasma) on all or part of the alveolar arch,

- an electrophoretic connection that ensures, depending on their polarization, the rapid evacuation of degraded components under the action of light or activated peroxide, and conversely, the penetration of bleaching products or gel loaded with restorative elements from the tooth,

- possibly a heat source, such as electrical filaments that allow a controlled rise in temperature at the level of the teeth to be treated,

- a gel containing the bleaching products and / or restorative ions used to conduct the current in the grooved device from the outside to the inside of the tooth and possibly another type of reverse polarization gel or identical to the previous one, but whose polarization has been reversed and charged with receiving, and eventually trapping, the displaced dye molecules out of the tooth. This gel constitutes the first polarization pole.

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The device also comprises a polar element, a kind of handle held by the hand or on the tooth, or even a flexible conductive surface applied to the back of the patient and which allows the reverse polarity in the human body to be provided to that applied to the gel. endobucal canal device. It is currently known that this polarity will be transmitted to the dental pulp thanks to the fluids present in the human body. The human body is therefore the second pole that creates the electrophoretic field with the gel of the grooved device.

The present invention also consists in associating the electrophoretic movements described here with a coherent set of known bleaching procedures, and in controlling the results obtained thanks to a simple monitoring system, such as, for example, colorimetry.

The invention therefore consists in whitening teeth more quickly to reduce the cost of treatment by actively transporting the bleaching products very close to the molecules responsible for their coloration, ensuring a new, unique and real evacuation of the degraded components, and reinforce the apatite structure of the enamel, thanks to the active contribution of ions such as calcium or fluorine on the site. This new and unique concept is applied thanks to the use of electrophoretic currents conjugated with a thermal or photonic activation system that favors and can result from electrophoresis.

It is also known that an electrophoretic current causes the temperature of the medium to increase, during the passage of the current without any other external intervention. Advantageously, the present invention therefore consists in selecting a gel carrying the active bleaching principles capable of optimizing the well-known ohm effect, which accompanies the passage of current, and which activates the active peroxide molecules at the same time, avoiding the use of external thermal or photonic sources.

Advantageously, and according to an additional characteristic of the device according to the invention, if the normal rise in temperature is not sufficient, it comprises a grooved device containing a single filament that serves both as an electrophoretic pole and as an electrical resistance pole that allows elevation thermal during the passage of current, thus creating the heat source. Indeed, it is known that any current flow is accompanied by an ohm effect. Thus, it is proposed here to use a polarization wire that also exhibits a rapid and consequent thermal rise during the passage of current, even reduced, and thus makes it possible to reinforce the chemical and electrophoretic effect already described, of a thermal effect that activates the molecules. increasing the energy vibration, making them more reactive.

Advantageously and according to another additional characteristic of the device according to the invention, the electrical filament will have a different importance or will be made of different materials, depending on the desired effect and, for example, and without this being limiting, it will be more important in the case of use. under the control of a professional, such as a dental surgeon, in order to obtain a stronger and faster thermal lift. It will be less powerful in the case of private use at home, in order to avoid any risk.

According to another additional characteristic of the device according to the invention, the means for adjusting the operating parameters of the heat source consist of selecting means in a memory connected to said central unit and selecting a certain profile among several previously registered profiles. in memory of. Indeed, it is known that an optimum temperature must be obtained in order to obtain the best possible activation reaction of the peroxide active principles. Above or below this temperature the molecule is less active. The purpose of the memory is to optimize the action time and the temperature obtained by the natural ohm effect or by the electrical resistance depending on the desired degree of action. These parameters resulting from laboratory tests and well known to specialists, allow the value of the potential difference between the two electrophoresis terminals to be previously adjusted a priori, and therefore, the power and the application time depending on the degree of action. wanted.

According to another additional characteristic of the device according to the invention, the means for adjusting the operating parameters of the electrophoresis and the thermal source are previously registered in the memory of the central unit according to certain parameters such as time and power, and are adjustable by the practitioner.

Advantageously in another case, a single parameter such as time is modifiable, avoiding any wrong manipulation, and this in particular within the framework of private use.

Advantageously, the memory connected to the central unit can be of the programmable type for recording the thermal profiles and / or data relating to one or more adjustable parameters, such as voltage or current intensity, suitable for selection.

Preferably, the device comprises data input means such as a keyboard and / or a touch screen and / or any other data input means, in particular remotely, for recording in the memory the energy profile and / or the data corresponding to an adjustable parameter in memory. In the latter case, the physician or the patient may follow the evolution of the treatment on a screen, by Internet or by confidential modem, or by any other means of transmitting information.

The remote data entry means include the parameters for adjusting the profiles, controlling the operation of the device and finding a possible fault, thus allowing remote monitoring, remote diagnosis or remote maintenance without physical intervention on the user's site.

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According to a further device of the invention, the grooved device contains sensors for measuring current or thermal or optical sensors that make it possible to know the evolution of the treatment before removing the grooved device. Indeed, it is known that at present it is impossible to follow and know the real state of the evolution of the bleaching treatment before that of the corrugated device. According to an additional device of the present invention, it consists of proposing to the practitioner a means to know this evolution, that is to remove the grooved device or act in feedback on the parameters, such as the potential difference, the intensity or the time following the behavior of the current, since it is known that the more an electrophoresis evolves, the more the characteristics of the current evolve. A priori, the variation of the electric current can be tested on an in vitro bench and reported in vivo, in order to follow the bleaching a priori without being obliged to remove the corrugated device.

According to the invention, there is an alternative to thermal activation. It is a photonic activation that can be included in the grooved device, and that comprises a light source and a channeling of the light on the site before receiving it. This mode of action may be a mandatory alternative, since it is known that some peroxides, such as those present in the "Ultra Light" marketed by "SHOFU" are more photosensitive than thermosensitive products. There is thus a light source that can be halogen, LED or plasma like the Apollo 95^ANDor any association between them and the light is therefore conducted by an optical fiber to the corrugated device. This radiation ensures, on the one hand, a photon activation corresponding to the wavelength selected as a function of the absorption spectrum of the peroxide molecule and, on the other hand, a thermal activation due to the release of heat that accompanies any halogen radiation or plasmatic.

Advantageously, this light source is made up of one or more light-emitting diodes (LEDs) capable of emitting activators of the teeth whitening reaction in the photosensitive zone, which are between 380 and 900 nanometers. These diodes, distributed evenly over the grooved device, for example in front of each tooth, allow the light to act at once on the entire alveolar arc.

Advantageously, these diodes use 2 wavelength sources, one that activates camphorquinone or PPDA (470 and 430 nanometers) and / or another that produces thermal radiation thanks to LEDs that emit red and infrared (for above 650 nanometers). The LEDs are small and can be deposited regularly on a relief holder and alternatively to distribute the wavelengths well over the alveolar arch. No light-conducting fiber optic is necessary, since the LEDs are small enough to be inserted into the patient's mouth. Only one power wire connects the LEDs to the power source. This source will preferably be a DC-DC supply such as that described in patent FR 2,818,892. Indeed, the mode of feeding can be the same as if it were an activation (peroxide) or condensation (polymerization) reaction.

Advantageously, these light sources have a programmable type profile that is variable in time, wavelength or power, pulsed or not, which makes it possible to optimize this activation reaction.

Advantageously and according to this mode of action, there will be a decoupling between the activation of the peroxide molecule, through camphorquinone, and the liberation of the fluorine ion. Indeed, it is known that the fluorine ion can be an inhibitor of certain reactions. Therefore, it is desirable that it be released specifically in the electrophoretic action after the action of the peroxide, that is to say after the degradation of the molecules responsible for the coloration. For this, the photon activation of the camphorquinone molecule and the liberation of the fluorine will be carried out, according to an alternative mode of the invention, by two different wavelengths, one emitted by LEDs at 470 nm for camphorquinone, and the other by LEDs. whose radiation will be different and will release the fluorine molecule, at the end of the clinical bleaching operation.

Indeed, and according to the description of the invention, there is a device that makes it possible to fill in the degradations of the dental structure during the evacuation of the coloring molecules.

It has become evident that the coloring molecules penetrate very deeply into the tooth, and lodge, either in the inter-crystal spaces, or in the crystal itself when it is not completely structured as a result of food deficits or drug treatments during its formation. (Tetracycline antibiotic therapy, NATHOO 1997). This situation, on the one hand, makes it difficult to evacuate, justifying high concentrations of peroxide and on the other hand, and this is dangerous for the tooth, a degradation of the crystal itself, which justifies the restriction of the use of bleaching products or the limitation in the percentage of active agents such as hydrogen peroxide by international health protection bodies. It has been known for a long time that the extraction of an ion, hydroxyl, calcium, or their absence, renders the hydroxyapatite crystal unstable and vulnerable. This is often the source of tooth decay. This is why fluoridations of the teeth are recommended, in order to fill these ionic deficiencies of fluoride or calcium.

The present invention therefore proposes to use the electrical resistance or a complementary resistance as a polarization field, which allows the active evacuation of the coloring molecules and used for bleaching (peroxide), but also the creation of an inverse field, simultaneously or later. , which allows a restorative ionic action such as fluoridation of the dental organ.

Indeed, it is known that fluoride is one of the determining elements to allow restructuring of the tooth crystal, enamel or dentin. It is for this reason that this ion is administered to children and adults in case of decalcification.

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This ion, in effect, has the function of filling the calcium deficiencies in the apatite crystal, allowing a stabilization of the molecular structure. It is also for this reason that it is placed in bleaching kits, such as the “Opalescence F1” which contains 0.11% (ie 1.1 ppm) per 5% of carbamide peroxide, but currently it must diffuse in a passive, therefore random.

Advantageously, the present invention proposes to inject this ion, or an ion with a similar action on the protection of the tooth, creating an electric field inverse to that used for the evacuation of the molecules responsible for dental staining or of the same polarity (positive to attract the fluoride, negative, inside the tooth) but during evacuation and after the action of peroxide. The action can be carried out at the same time as the action of the peroxide, as long as the ion used is not an inhibitor. The present invention proposes sequencing the polarities according to the desired effect: peroxide action, dye evacuation and tooth reinforcement depending on the possible inter-relationships of the molecules with each other. The fact of using an electrophoretic mode not only allows these molecules to be actively displaced, but also guarantees the separation of chemical actions, in order to avoid any interactive action that could be negative between the different reactions. It is the only method that allows to affirm that there is no chemical interrelation in the phases before they are separated.

For this, the present invention can be summarized as an electrophoretic and chemical device, in a thermal accessory way, for bleaching, which comprises an energy source that supplies an electrophoretic current variable in its polarity, and whose conductive wires are joined, on the one hand, to the patient's body (first pole) and on the other hand (second pole) to a grooved device containing the chemicals responsible for a bleaching treatment. These electrical conducting wires present in the grooved device allow both the thermal elevation by the Joule effect (they can be replaced by a photonic source) but also, due to their variable electrophoretic polarization, the movement of the molecules towards the interior of the tooth so that they are active quickly and deeply (such as peroxide molecules or fluorine ions, molecules that are restorative of the tooth after bleaching), and the reverse movement towards the outside of the tooth, ensuring an active evacuation of the molecules responsible for the coloration. The electrophoretic field is at the level of the tooth. One of the poles is held in the hand or on the patient's body, this polarity is transmitted through the blood and lymphatic vessels to the dental pulp, and the other pole is transmitted by the electrical resistance present in the grooved device.

Other objects and advantages of the present invention will become more apparent from the following description, which refers to an embodiment given by way of an indicative and non-limiting example. The understanding of this description will be facilitated with the observation of the attached drawings, and in which:

- Figure 1 represents a schematic view of a device for whitening teeth according to the invention,

- Figure 2 represents a partial and exploded schematic view of a part of the same device,

- Figure 3 represents a schematic cross-sectional view of a part of the same device during a bleaching operation,

- Figure 4 represents a schematic view in partial section of another part of the same device,

- Figures 5a and 5b are diagrams of the representation of a cycle of analysis of the color of a tooth,

- Figures 6a and 6b present partial schematic views of variants of the same device,

- Figure 7 is a schematic illustration of the different stages of the treatment applied by the device according to the invention,

- Figure 8 represents a schematic perspective view of a variant of a part of the same device,

- Figure 9 represents a diagram illustrating the different stages of the treatment applied by the device according to the invention,

- Figure 10 represents a schematic view in vertical section of a devitalized tooth during its treatment with the device according to the invention, and

- Figure 11 represents a partial schematic view of a particular embodiment of the device according to the invention, adapted to nail treatment.

As represented in the Figures, the present invention relates to a bleaching device that will find a very particular interest in the dental field.

As can be seen in Figure 1, this device comprises a standard grooved device 1 with its electrophoretic resistance 2 and a series of activating LEDs 19 connected by electrical connections 3 to an electronic command, control and memory box 4 and to a control handle. reverse bias 23.

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The standard grooved device 1, intended to cover the dental arch to be bleached, is provided with an electrical conduction system 2 that allows the creation of an electrophoretic field, accompanied by a thermal rise, which has a positive or negative polarity, and which is connected, for example by an electric wire 3, to an adjustment and control unit 4, contained in a box, which allows defining or programming the parameters of the clinical treatment (time, degree desired by the patient ...) and those that define the electrophoretic field (intensity, voltage ...). These controllable criteria in the quadrants 5 can be modified by manipulation of the control buttons 6, teletransmitted remotely in a geographically remote system and thanks to a digital connection (modem ...) 7, memorized on a diskette 8 or stored in a central unit 9. In a socket 10, an on / off pedal 11 can be installed for any intervening factor, such as the activation light and / or the electrophoretic field, and / or a spectrocolorimetric analysis moment. The head 12 of the latter receives, thanks to a conductor 13, the light emitted by the reference LEDs, which can be red, green, blue and by return, the information modified by the measured object, in this example a tooth. This conduction is carried out by optical fibers or directly on a sensor 14, which sends the measured values ​​to the analyzer located in the unit 4. The selective start-up of the spectrocolorimeter is carried out, through conduction means 15, thanks to a button 16 located on the facade of unit 4 and the result obtained is visible on an alpha-digital screen 17 located above. The start-up of the caloric system, thanks to the selective button 16, conducts the sending of energy through a wire 18 that induces either the illumination of the LEDs 19 located on the grooved device 1, or the thermal elevation of a resistance 20 located in the grooved device 1 if the wire that creates the electrophoretic field 2 is insufficient. A probe 21, thermal or electrical, will indicate by return the status of the electrophoresis to the central control and information unit 4. The reverse polarity to that created by resistance 2 will be transmitted to the pulp, through the blood or lymphatic system, etc., thanks to a handle 23 held in the hand and connected to unit 4 by a thread 24. This polarity can be reversed automatically or by action on button 6.

The activation of the peroxides can be carried out thanks to the rise in temperature of a common thermal resistance with which it is used for electrophoresis 2 or independent of the latter 20 if the selection of a different shape and / or material can optimize a or another of the functions.

It will be noted very particularly that the present invention is in no way limited to an electrical activation of the basic components present in a bleaching gel 25 into active components on the coloring and electrophoresis-sensitive products. Indeed, this activation can be carried out, according to the invention, by electrophoretic means. In this case, a resistor 2 ensures electrophoresis, and an activating light source is led from a lamp located in the electronic unit 4 to the bleaching gel via an optical fiber 18, or is produced directly by the LEDs in the vicinity of the latter 19. In the latter case, the optical fiber 18 is replaced by an electrical conduction wire that ensures the power supply of the LEDs.

In order to control by feedback the temperature, the characteristics of the electrophoretic current and / or the light power, a thermal, electrical and / or photonic sensor 21 is provided connected to the central control unit 4 by a connection wire 22, or by a communication by waves. These sensors 21 send the necessary information to the central unit for it to control whether the treatment is carried out with respect to the settings programmed in the central unit 4. This feedback allows regular, even continuous and automatic adjustment with respect to the programmed functions. It goes without saying, of course, that the central unit is not mandatory for the application of the invention, and that a simple manual adjustment may be sufficient in a rustic use.

If it is decided to use a gel 25 sensitive to the electrophoretic current produced by poles 2 and 25, and which has the characteristic of changing color at the moment of its activation after its migration, this sensor 21 can be a photosensitive cell, such as a photodiode. . In this case, applying Bert Lambert's law, which relates the concentrations to the intensities measured by the photodiode according to the formula Ic / Io = log Cc / log Co, the evolution of the concentration of the active principles in the tooth can be followed. and the return of degraded colored molecules. The projection of the light of the analysis is carried out at the level of the head 12 of the colorimeter, while the reading is recorded thanks to a CCD or a photodiode located in the head 12 or in the sensor 14.

Now with reference to Figure 2, which is a schematic representation of a flexible conduction plate that can be adhered to the surface of the teeth before a grooved device adapted to the patient's mouth in a traditional manner is placed, It is appreciated that the electrophoretic conduction plate 2 can be constituted of a flexible conductor 26 that can be adhered to the surface of the teeth before a specially molded and adapted grooved device is placed in the patient's mouth in a traditional way by the dentist. or the prosthesis manufacturer. In this case, the flexible plate 26 adheres to the teeth or is pre-molded on the relief of the patient. According to a work well known to professionals, an anatomical ribbed device is then made, that is, specifically molded in resin on the shape of the patient's mouth. This ribbed device can be made of a transparent material to allow activation of the gel with peroxide (or activated by another chemical principle) by a light applied from the outside. In this case, the electrophoretic filament must be adhered as much as possible to the tooth or it must be made up of a conductive material that is transparent as charged resins. The electrical supply is made through a conductor 27 and its complementary 28 if it is desired to be able to separate the grooved device 1 from the unit 4 for obvious practical reasons.

With reference to Figure 3, which represents a section of the grooved device 1, it can be seen that the socket 28 is divided into two parts, one for the power supply 31 and the other for the on / off control of the thermal resistance by thermal energy 34 or photonics if LEDs 19 or any other light source are used. The gel 25 being conductive,

ES 2 268 481 T3 the resistance 2 for creating the electrophoretic field need not be very important, and the polarization of the field is perfectly dispersed. The function of the light 19 or the thermal resistance 34 is to promote the initiation of the activation reaction of the bleaching gel 25 that is in contact with the tooth 30 and a small part of the gum 35 even if this is not desirable, due to the natural aggressiveness of peroxides on soft tissues.

It will be noted that, in a non-limiting manner, the socket 28 is of the switch type. It may comprise more than one separate contact if it is to link feedback control or various other types of polarization.

Figure 4 represents a low-cost differential colorimeter 14 that serves as a control unit for the effectiveness of the electrophoresis bleaching treatment, while Figures 5a and 5b are diagrams, respectively A and B, of the representation of a cycle analysis of the color of a tooth, respectively before and after bleaching. The differential colorimeter is a very simple system based on the differential measurement of a color, before and after the treatment by reflection on tooth 30.

The principle of the manipulation is as follows: a light source composed of several LEDs 38 fixed on a support that evacuates the heat release 39 is contrasted, powered and controlled by a DC / DC 40 card. These LEDs are of number (minimum 2 ) and variable color, but preferably Red, Green and Blue (RGB system). They emit radiation that is recovered by an optical concentrator system and then conducted, after separation in a space, partly on tooth 30 and partly directly on a sensor 45 (generally a photodiode, a CCD or a CMOS), with or without mixing. It is possible to separate the same beam into two parts and carry out the measurement on two or a single sensor. It is also possible not to use more than a single sensor 45 delaying the measurement in time. The information will be conducted from the sensor 45 through a junction 47, to a differential comparator 48 which, thanks to the analysis of the difference between the incident beam, scheme A, and the reflected beam, scheme B, will be able to provide a value of tooth coloration and you can compare it with the value measured before treatment.

If care is taken to memorize in the central unit 9 the standard dental shades well known to those skilled in the art (Vita shades for teeth ...), with the same method, and the same reference (contrast test), it is possible view, on the alpha-digital screen 17, and follow the evolution, and thus the effectiveness of the treatment based on criteria recognized by professionals. Thus, it is possible according to the invention to make an objective measurement of the results of the treatment without being obliged to resort to very expensive methods.

As indicated in Figure 6a, the ribbed device can be only partial 49 or mono dental 50 if it is not desired to treat certain teeth 30 for medical reasons (pain in the teeth ...) or if you have sensitive gums 35. Connector 27 will preferably be identical regardless of the type of grooved device.

Likewise, and as shown in Figure 6b, it is possible to have a connection 27, without the grooved device, simply attached to the electrophoresis wire 2 whose length can be adapted, by making a section 51 to eliminate a part 52, in order to limit it to a few teeth.

In order to fully understand the function of the device, object of the present invention, the action of the electrophoretic electric fields as applied has been represented in Figure 7. It should be noted by way of example that there may be, and this is not limiting, three successive times of action using electrophoretic bleaching currents.

- initially, the electrophoretic current transports the molecules rich in bleaching product, such as carbamide peroxide 54, present in the gel 25 into the tooth 53. If the molecules carrying the active groups are negatively charged, the polarity 55 of the resistance of the ribbed device is negative and the polarity of the body, held for example in the hands of the patient, is positive. This polarity is transmitted throughout the tooth, through the odontoblastic cells that border the pulp 58, mainly at the dentin / enamel interface 53 where a concentration of molecules responsible for staining is frequently found 59. In this way, an ionic movement towards the center of the tooth, pushing the active molecules against these stains. If the active molecule is not charged, it can be passively transported in the ionic movements created by the additional fluids made up of highly charged molecules,

- in a second stage, a unique inverse movement is created, the center of the invention, and which aims to extract from the tooth the coloring molecules 60 that have been degraded by the bleaching agents 61. It is evident that they are the coloring molecules of an inverse polarity to that of the resistance which will be extracted from the tooth. This polarity present in the gel 62, being the same as that of the bleaching molecules 54, the non-degraded or non-reacted molecules are extracted from the tooth to prevent them from continuing their action beyond the treatment and from being able to damage tooth components (which makes them hypersensitive and can even degrade them). This also allows you to actually stop the procedure at a defined and selected time. This technique is the only one that makes teeth whitening controllable.

- Finally, in a third stage, but this is not limiting in the principle of the invention, the gel resulting from the action of the first two stages, loaded with the dyes and the active product molecules that have reacted, or not, like peroxides, it is removed and replaced by a gel rich in fluorine, and / or in

ES 2 268 481 T3 any other restorative product of the tooth, electrically charged as the carrier molecule of the active groups (peroxide). The polarity of the resistance present in the gel is again reversed 63 in order to allow, on the one hand, the penetration of the fluorine ions (or others) 64 and on the other hand to attract the dye molecules that have a reverse polarity and that have been retained in the tooth for time 2.

It is clear that, and this is also in the principle of the invention, fluorine can be present in the active bleaching product and migrate with the gel in time 1. The polarities are compatible. This solution has the advantage of avoiding the gel change at time 3, since it is then sufficient to invert the polarities twice. Instead, this has the drawback of bringing two molecules together that may be incompatible, fluorine is a well-known reaction inhibitor.

Advantageously, if it is desired to accelerate the clinical procedure, it is possible to proceed only with a single polarization in the sense of the penetration of the active molecules, with or without fluorine or of the exit of the degraded molecules after the action of the molecules. active outside the electric field. This method can be interesting if the behavior of certain active molecules is disturbed during their reactions on dyes.

It is also possible, according to the invention, to program sequences without electrophoretic current, for example between times 1 and 2 and between times 2 and 3. This can make it possible to complete certain reactions sensitive to electric current.

Likewise, any form of intervention on the electrophoretic current is feasible within the framework of the invention. So you can, in a non-limiting way:

- act on the intensity. It has been experimentally demonstrated that it is possible to significantly increase the action of the technique according to the invention by rapidly increasing and then decreasing the intensity of the current, and this, by successive waves,

- to vary the polarization of the poles, not in three times, but in an alternative way, to allow certain molecules to find their most favorable path to their trajectory in the crystal of the tooth,

- use this alternative principle, acting on the time granted to each polarization. The times as defined above have been preserved, but the polarity has been reversed several times and rapidly. Overall, a positive or negative polarization corresponding to the mentioned times will be obtained, but it is interspersed by a reverse polarity that allows the molecules to circulate in the tooth, and eventually, to free themselves from steric or electrical stagnation.

In Figure 8, according to a variant, the thermal rise is provided, not by an electrical resistance, but by a circulation of water or any type of thermal vector in the conduits 66 that run through the grooved device 1 that penetrates through a hole 67 and leaves through another 67. This vector can be a liquid or a gas, like hot air. It is evident that this assembly does not prevent the addition of the electrophoretic field. In the example represented in this Figure, and which corresponds to a possibility of the application of the invention, the field is carried by the grooved device 1 itself, which is made of conductive material, and the connection 27-28 is visible under the conduits of the thermal vector.

The diagram in Figure 9 illustrates the successive stages of operation, in the case in which the molecules responsible for the coloration of the tooth are positively charged. The non-activated product is placed in a standard or custom grooved device 69. The principle of activation or acceleration of the activation of the molecule based on peroxide or another is set in motion thanks to a thermal or photonic elevation 70. The active product 71 has a negative valence (in our example) 72. A feedback control can limit the energy supply at any time, directly measuring the temperature 73 and / or following the evolution of the electrophoretic current. It is in effect at this instant that the electrophoretic field is created by placing the contact on the grooved device (negative), and requesting the patient to hold the other (positive) pole 74. There is a penetration of the active negative radicals into the tooth 75, attracted by the positive charges of the pulp and rejected by the negative charges of the grooved device. The peroxide molecules are then in direct contact with the dye molecules 76. This makes it possible to significantly reduce the doses currently used, and thus protect the tooth. The polarity has then been reversed. The degraded and positively charged dye molecules come out, attracted to the negative pole of the ribbed device 77 accompanied by the peroxide molecules and by the uncharged molecules that can be passively transported 78. The polarity has been reversed one last time, in order to allow the penetration of fluorine 79. The feedback that measures the physical characteristics of the electrophoretic current can intervene at all levels 80.

Advantageously and according to the invention, the molecules of the active products, such as carbamide peroxide, are charged during their conditioning, thus avoiding the activation phase, or they become charged during the activation phase by energetic means described above. These charges can be carried by a radical of the molecule independent of the peroxide radical or of any other bleaching product (reducing and / or oxidizing).

It is also recalled that according to the invention, and to favor the movements of the uncharged molecules that take part in the bleaching actions, it is possible to move, thanks to an indirect electrophoretic action, the molecules, transporting them through a charged fluid present in the gel or aggregate. to the latter. To this end, and according to the invention,

ES 2 268 481 T3 provides a gel capable of penetrating the tooth, without chemical action on the dye molecules, but very dynamic. The reversal of polarity in the tooth will cause it to return to the outside of the tooth, transporting the degraded and staining molecules through this second inverted movement (fluid dynamism).

Advantageously, the gel containing the whitening product (for example carbamide peroxide) and / or the tooth strengthening product (for example fluoride) changes color depending on the concentration. For example, the movement of the peroxide groups in the tooth decreases their concentration in the gel, increasing it in the tooth. This makes it possible, according to the invention, to follow the progression of the clinical procedure, and to stop it at a color known as corresponding to a good concentration of the active peroxide groups in the tooth, and to ensure a good bleaching action. The same observation can be made during the migration of the fluorine (for example) or the return of the dyes.

Advantageously and according to the invention, the gel contains molecules that, in contact with the colorants, become of an inverse charge to that present in the bleaching molecules (peroxide) or transform the charge of the degraded colorant into an inverse charge to that of the peroxide. This method has the advantage of suppressing time 2 of the electrophoresis, since the charges of the dyes and those of the degraded dyes are in this case, and according to the invention, the inverse of the charges of the active bleaching molecules (peroxide) . They will undergo an exit movement of the tooth opposite and simultaneous to the penetration of the peroxide without the need to reverse the polarity. There is thus a fusion of times 1 and 2, described in the Example of Figure 7, and only two action times: times 1 and 3. If the tooth strengthening agent (fluorine) is present in the initial gel, it is not It is necessary to create a polarity inversion, and a single time is then possible.

It is evident that according to the invention, the charged products being very vulnerable, the activation and polarization of the active compounds such as carbamide peroxide are carried out by mixing the base compounds, before their introduction into the corrugated device.

To answer a concern about automation, a current measuring sensor 21 (potential difference, intensity ...) can be added to the electrophoretic gel. Indeed, it is known that during electrophoresis there is a progressive variation in the characteristics of the applied current, particularly when the ionic movement ends, these values ​​tend towards infinity, and thus it is easy to foresee an automatic interruption, or an indication of the end of the cycle, and thus know if the treatment is finished based on previously memorized scientific criteria.

It is clear that, according to the invention, the thermal / electrical resistance of the electrophoresis will serve for the feedback control of the light emission. The recorded values ​​make it possible to know whether or not the photonic action of light should be interrupted. It is also possible to vary this light power by adjusting the parameters controlling the electrical power that powers the LEDs. The use of the DC-DC procedure as described in document WO 03/068102 makes it possible to obtain this result under the best conditions.

Other systems commonly used in the dentist's office or at the patient's home can be associated with this concept of energy control applied in whitening. Thus and according to the invention, the power used at home for electrophoresis can be shared with that used for powering or recharging electric toothbrushes or portable telephones (while traveling). This duality allows to significantly reduce the price of such a device. Also in the dentist's office, the association of this electrophoretic system with ultrasonic assemblies or with projections of abrasive products (bicarbonate ...) makes it possible to conceive a whitening center that incorporates all the devices used by the expert in the art, without significantly increase the cost, since the most expensive elements (food ...) are put in common for several technologies.

Advantageously, the regulation and control of the parameters that allow the application of this invention is dependent on a CPU, the same one programmed by the person skilled in the art. There is an integrated circuit card system that allows these parameters to be programmed, and it is sufficient for the patient to insert the card given to him by his dentist to be sure that the parameters that define electrophoresis comply with the rules of the technique. In short, the device according to the invention provides the user with the possibility of regulating and adjusting the operating conditions of his apparatus as and where he wishes, so that he is not limited as in the past to the blind and empirical action of the device. peroxide without control or monitoring.

Advantageously and according to the invention, the colorimeter 14 is associated with this feedback control. It is known that the color of a body is a function of 3 criteria called LAB, xy and Y, RGB or others, according to the theory followed. The fact of using a color detector 14 in the device makes it possible to follow the evolution of bleaching in the course of treatment. This measurement can be carried out, according to the invention, at the level of the gel that can be discolored or colored according to the contribution of the coloring molecules or by reaction with the latter, as described above. This allows you to know whether or not the application should be interrupted, and avoids having to proceed empirically. This also avoids interrupting the action before the end of the treatment and allows to limit the committed expenses. Likewise, this measurement system can be done on the tooth, before and after treatment, thus allowing the practitioner to show his patient the evolution of bleaching. For this, a special sensor 12 was developed composed of the color meter precisely described in Figure 4, and whose end can:

ES 2 268 481 T3

- either integrate into the gel,

- either placed on the tooth.

It is no less true that most bleaching devices cannot act on devitalized teeth, or they do so through high concentrations, or with the use of specific products such as borates. The present invention would be the same if a solution were not proposed, since the pulp and blood circulation having been removed, there can be no electrical conduction in them of the reverse polarity to that of the gel, inside the tooth. The present invention proposes a specially developed alternative for devitalized teeth. Advantageously and according to the invention, as seen in Figure 10, the pole held in the patient's hand or placed against his body, is replaced or is coupled (in series) with a probe S that can be inserted into the dental canal 81 of devitalized teeth 82 and previously calibrated. A conductive gel 83 is placed in the canal in replacement of the non-existent dental pulp, after care has been taken to moisten the tooth. The driving function of the second pole is thus recreated even in the absence of the pulp.

Advantageously and always according to the invention, this gel contains active bleaching components and fluorine, as observed in the external gel, but in reverse polarity, in such a way that they are attracted to the gel of this external grooved device. A second movement of the active molecules has been created inverse to that of the grooved device at the outer pole. If there are no active molecules of reverse polarity , it is sufficient to repeat the operation sequentially: external bleaching, and then internal bleaching, etc., using the same gel and the same polarity (as described in Figure 7, but having a reversal of polarity, depending on whether the active gel is inside or outside the tooth.

This extension of the invention has the advantage of allowing a bleaching technique for devitalized teeth, which is very important since they are frequently the most colored teeth. This also has the advantage of increasing the action of the products even more significantly in that they are electrophoretically displaced towards the colored molecules on the outside and inside the tooth. Associated with this double internal and external action is an action of removing the dye molecules from both sides. In this case, and to understand the bleaching mechanism from the internal pole, it is enough to invert times 2 and 3 of Figure 7.

With reference now to Figure 7, it can be seen that the invention is not limited to teeth whitening, but also finds an application in the treatment of other parts of the body, such as tissues or hair, and in this case the nails. . This Figure thus shows a gel support means 84, adapted to the end of a finger 85, and covering the nail, not visible, of the latter.

It stands out from the preceding description that the present invention perfectly responds to the problems raised, in the sense that it provides a real answer for optimizing teeth whitening and protecting the dental organ. It also stands out from this description that it allows solving fundamental problems, such as the control of the clinical act, which no other method has yet proposed.

It is evident that the invention is not limited to the only embodiment of this method, nor to the only embodiments of the device for the application of this method, described above by way of examples; it covers, on the contrary, all the variants of application and implementation. In particular, it would be possible to bleach objects other than human body parts, such as statues or fabrics. It is also possible to provide a type of industrial bleaching based on the present invention and which ensures the penetration movements of the cleaning body or removal of the molecules responsible for the coloration by electrophoresis.