WO1986006265A1

WO1986006265A1 - Process and equipment for examination electro-chemical effects of metal replacements (implantations) in living organism

Info

Publication number: WO1986006265A1
Application number: PCT/HU1986/000025
Authority: WO
Inventors: Zoltán BAY; György VUKÁN; Magda LAKATOSNÉ VARSÁNYI; Zoltán VASS; Laura SZIRÁKI; László KISS
Original assignee: Bay Zoltan; Gyoergy Vukan; Lakatosne Varsanyi Magda; Vass Zoltan; Sziraki Laura; Kiss Laszlo
Priority date: 1985-05-02
Filing date: 1986-05-04
Publication date: 1986-11-06
Also published as: EP0220262A1; HUT40003A; HU192218B

Abstract

A process and an equipment are used for examination of electro-chemical effects inducing inflammation and allergic symptoms in the living organism, which are induced by two or more metal replacements respectively by other, in the living organism implanted metal (implantation). During the procedure according to the invention at patients with inflammatory and/or allergic symptoms it is controlled by in vivo current-measuring near the approachable metal replacements (implantations), if the ion current - which is established on the effect of galvanic cell has been created by metal replacements - reaches the allergic symptoms or the critical value inducing inflammation, further on the values of electrode potentials measured on the implantations are compared to the anode-polarization curves given to the metal replacement alloys, and on the basis of it the conclusion is drawn on the measure of ion current developed between certain metal replacement pairs. The equipment according to the invention consists of an electronic unit (1) and probe (2, 3, 5) used for measuring current resp. electrode potential. In the electronic unit there is a current-voltage converter (11) sensing current to be measured, an instrumental amplifier (12) sensing voltage to be measured, a precision rectifier (13) connected by its input with the output of formers, and on the output of it a suitably logarithmic amplifier (14) is connected, and on the amplifier a voltage-current converter is connected, which drives a suitably analogous indicator, especially Deprez-instrument (16). For the sake of the simplier handling, the equipment can be supplied with sound and/or light-source, which give signal for the doctor in case of overflowing a given value (voltage or current) about the presence of pathological ion-migration.

Description

PROCESS AND EQUIPMENT FOR EXAMINATION ELECTRO-CHEMICAL EFFECTS OF METAL REPLACEMENTS (IMPLANTATIONS) IN LIVING ORGANISM

The invention relates to examination electro-chemical effects of two or more metal replacements in living organism, and equipment to implement the process, which contains an electronic unit and electrode potential measuring probes.

Background of the invention

It is known, that in the last 15 to 20 years, as a result of the rise in price of dental noble metal alloys, there is a growing demand on production and use of common metal alloys suitable for dental use, even in the richest countries^'. First of all the number of nickel-base metal alloys is high (Ni content is: 60 to 75 %) , which also contain chrome and cobalt in a rather big percentage. Accordin to the relevant literature e.g.: H. . Gundlach: "Edelmetall- -Dentallegierungen: Edelmetallfreie-Dentallegierungen" (Dental-Labor 30,321 /1982/, Sonderdruck) , or D. Hermann:- "Allergische Reaktionen durch zahnarztliche erkstoffe", ( ZM Fortbilding 18/1981) , manifestations of allergy can be shown in connection with all the three metals. The presumable cause of this, that the a.m. metal alloys in the mouth or in other part of the body (e.g. in case of pacemaker in the chest) may form galvanic cells together with metal alloys set in or metal alloys to be set in (amalgam filling, metal crown, bridge, metal plate) . That means, that metal ions can be dissolved from the metal alloys on the advantageous temperature of the mouth and pH towards the living tissues. In this temperature ( 35 C) the dissolved metal ions can very easily join to protein bodies, and as a result of it, allergic reactions can be appeared in the organism, which were previously senzibilized by metal (e.g. local and distant mucous membrane- and skinreactions, for example: eczema, dermatitis, dermatosis, etc.). This reaction remains till the factor, which caused allergy (for example: prothesis made of dental metal alloy) will not be removed. The methods known and used up till now for clearing up metal replacements which induce allergic focus, are based on in vivo measuring potential difference among metal replace¬ ments already set in, respectively before setting in new replacements, the expectable ion migration will be determined in vitro well in advance by complicated laboratory procedure so, that the metal replacements, as electrodes, will be placed into electrolyte mimitating tissue fluid, or often into saliva taken from the mouth of the patient.

After all neither the voltage measured in vivo in the mouth, nor ion current values can be measured in vitro mean substantial information for the diagnosticating dentist. In the publication was written in the beginning of 1983 "Noble metal alloys. Common metal alloys." Dr. Gundlach (Bego) deals intensively and first with the electro-chemical symptomps occured in connection with dental metal alloys in vitro circumstances.

In his study he points out, that each metal alloy passes its ions only.over a certain electrode potential limit characteristic thereof, up to this potential limit it is protected from this by an oxide layer, which passivates it. In accordance with this the so called anode-polarization measured curve can be / , which is characteristic for each m fcal and it can be punctually determined from it, up to which

C_____E*I*Θϊlil electrode potential is there so called passive / (when current ' there is no any/ ) and from which electrode potential is current there again active / . It is demonstrated by Gundlach s figure. (Fig.4.) . current As a consequence of the passive / period, respectively of the non-linearity of electrode potential curve, not every potential difference induces ion current producing allergic symptoms, so from the voltage measured in mouth among metal replacements we can not drive to the conclusion unanimously of ion migration.

The disadvantage of in vitro measurement of ion migration is, that the body-electrolyte of the patient can not be .substituted only by saliva and besides this, only the early period of development of galvanic cell can be examined by this kind of systems, when the oxide layer on the electrodes (metal replacements) prevents formation of ion current which later can be dangerous.

The invention is aimed at insuring a process, by the use of it the reasons- inducing allergic symptoms of senzibila patients - can be diagnosticated by measuring the electrode- -potential of prothesis, respectively the metal replacements responsible for injurious ion migration can be determined, and the patient can be cured by the removal of it. The invention is also aimed to prognosticate - by the application of the process and by measurement of electrode- -potential-the expectable effect of a given alloy of metal replacement after setting in, respectively by the use of this it can be easily selected the alloy, which will have probably no any injurious electro-chemical effect to the living organis Further on, the invention is aimed to insure a process and an instrument, by the help thereof ion migrations, which induce allergic symptoms, and are characteristic to the rate of corrosion, can be simply and reliably in vivo cleared up. The invention is also aimed to insure an instrument, which is able to measure and indicate not only in vitro, but first of all in vivo the undesirable ion migration in the examined persons in certain circumstances, and it is suitable to decide that the metal replacements set in are in acti-veorpassive state in respect of allergy.

The base of the invention is the recognition, that the in vivo electro/potential measurements can be extended to^' prognostic aims, if the measured values will be compared with the electro-chemical properties of the metal alloys already implanted, or to be implanted, or metal alloys come into question in this purpose.

Brief description of the invention The substance of the invention on- this recognition is, that at patients with inflammatory and/or allergic symptoms, we controll by in vivo current measurement in the nearby of the approachable implantations, that ihe ion current which developes under the influence of galvanic cell establish by metal replacements - teaches the critical value, which occures allergic symptoms or inflammation.

In case of local complaints, for example: oral mucous membrane inflammation, the measurement of ion current gives enough help to determine the allergen,' while in case of distant, allergic complains it is advantageous to complete the current measuring with dermatological specific test. By the help of the test it can be exactly determined, which metal component in the alloy of metal replacement is responsible for the development of allergy. The above written steps of the process can be applied advantageously in the course of diagnostical examinations. that means, in cases, when metal replacements are in the organism for a long time, and the medical attendant must establish, that the metal replacements are responsible for inducing inflammation and/or allergic symptoms, and if they are, then which of the metal replacements, respectivel which component of its alloys is allergen, namely the material for which the organism of the patient sensitive is.

The "in vivo" measured electrode potential values of metal replacements will be compaired according to the invention with the anode-polar-ization curves given for the alloys of metal replacements and on the basis of it we can conclude to the rate of corrosion of metal replacements. The expectable electrode potentials of the new metal replacements to be set in compared with the metal replacemen already set in will be "in vivo" measured - according to the invention - by touching the recipient tissue to the specimen, made of the same material as the a.m. new metal replacement, and we compare the result of the electrode potential val measurings with the anode-polarization curve of the new alloy, and predict ^tne measure of the expectable .ion curren after the implantation.

Utilization of specimen can be applied advantageously at prognostical examinations, in cases, when the medical attendant has to decide, that the metal replacement to be inplanteted will be in activeor passive . state i^{n tne} organism of the examined patient, resp. he has to select the metal replacement from those ones, come into question, which stays passiv implantated in the organism of the patient, that means, it doesn't induce allergic symptoms or ion migration inducing inflammation under electrode- -potential circumstances. In accordance with this fact, the instrument, which is suitable to execute the process, is supplied with a specially developed probe which is good for measuring voltage and current, and connected by cable to the electronic unit, and is also supplied with a set of specimen made of the material of metal-replacement. Further on the most general construction of the electronic unit consists of: current- -voltage converter, which receives the current to be measured, an instrumental amplifier, which senses the voltage to be measured, precision rectifier, which connects with its inputs to the outputs of the before mentioned two circuits, in given cases a logarithmic amplifier connected to the out¬ puts of the before mentioned precision rectifier, voltage- -current converter, which follows the log.arithmic amplifier, and a Deprez-instrument, which is advantageously analogous and is driven by the converter.

The construction of the equipment according to the invention proved to be advantageous, by which one of the inputs of the comparator - driving a sound detector and/or flash signal appliance - is connected to the output of the logarithmical amplifier of the electronic unit. The other input of the comparator is joined to another voltage source.

Another construction of the probe used for measuring electrode-potential proved especially advantageous, and consists of a hollow insulator shaft, a cup which can be hermetically locked on the top, a hygroscopic material, which can be put in the open bottom of the shaft, an electrolyte inside the shaft, suitably synthetic saliva, silver- and silverchlorid/electrode of the second kind immersedin the electrolyte, and it is linked by a metal thread with one of the inputs of the instrumental amplifier of the electronic unit. A feeler probe ending in a metal peak (suitably made of Cr-Ni steel) and supplied with an insulating handle, proved advantageous, and it is linked by a metal thread with the other input of the instrumental amplifier of the electronic unit.

Certain speci___an of the set of specimen made of available materials of the metal replacements seat on the measuring peak of the feeler probe and can be plugged in.

Another construction of the ion current measuring probe is also advantageous, where on the end of the measuring peaks of the probe, platinum hemispheres are fastened, which are linked by a -etal thread leading through the measuring peaks with the currer.r-voltage converter of the electronic unit.

Brief description cf -he drawings

Further on ve represent the invention in details on the bases of a ccr.s-ructing pattern with the use of the enclosed drawing, where

Fig.1. block-sche_r_a cf the equipment according to the invention

Fig.2. drawing of _^'r. ^~ reference probe used for measuring electrode-potential Fig.3. drawing of feeler-probe used for measuring electrode potential Fig.4. an anode-pclarization curve given for alloy of metal replacement Fig.5. drawing of the probe used for measuring ion current Fig.6. specimen.

The diagnostical examination of a patient with local complains (inflamnation) , is the following according to the invention: Brief, description of the preferred embodiments

The current measuring probe can be used in the surrounding of the questionable metal replacement, suitably on the gums (gingiva propria) . As only a small part of the 5. tissue, which forms the current way, is touched by the probe at the same time, the electronic unit will indicate not the whole ion current which flows among the activ metal replacements, forming the galvanic cells, but only a small percentage of it. 0 According to clinical experiences this is already enought to establish the diagnosis, because the partial current driven by the probe to the electronic unit is proportionate to the total ion current, in every case.

As a result of examination and measuring on a great number 5 of patients, the ion currents under 30nA can be regarded normal, while ion currents over 50nA are regarded pathological, in every case.

Measuring in the mouth on the mucous membrane we must take good care to measure ion current on that part of the nucous membrane, where the bio currents, which occure in the mucous membrane can be moved or.they move on the effect of muscle movement, can not influence the result of measurement

That kind of place is for example the gingiva propria.

The proper place of gingiva propria and the electrodes on the end of measuring peak must be dried by air before measurement.

In case of local complains (inflammation, gingivitis) additional dermatological test is not needed, the patient can be cured by the removal of activ metal replacements, which are responsible for inflammation, resp. by the implantation of metal replacement made of satisfactory material - 9

In case of examination of patents with allergic (distant) complains the above mentioned cure can be completed with dermatological specific allergology test (cutan-test), and as a result of it, it can be told, which metal component of the alloy is responsible for establishment of allergy_

By writing the pathogenic allergen metal on to the case- -sheet those alloys can be eliminated in the future, which contain allergen metal₀ In case of therapy treetment, we eliminate the metal replacement' alloys containing allergen metals from the assortment come into question during the implantation. When thiskind of allergen doesn't occur from the case-shee we look for them by in vivo ion current measurement, according to the invention, respectively in certain cases •by dermatological testo

After the removal of the anodically dissolving member of metal replacement-couple, which has been found very active by ion current measuring, we choose a specimen made of similar material in respect of elec rodepotential to that part of replacement-couple, which stays in the mouth, then we plug it in the measuring peak of the feeler probe, and we touch it to the mucous membrane on the place of the new metal replacement. At the same time we measure the electrode potential of metal replacement to reference referring electrode, so that we touch the end of electrodepotential measuring probe to gums and the feeler probe to the previously ,air-dried metal replacement, respectively. We repeat voltage measuring several times rotating the metal replacements to be implantated. We choose advantageously the gingiva propria on the mucous membrane and we dry the specimen by air before measuring.

The result of electrode potentialwill be compared with anode-polarization curve given to the chosen specimen and alloy of fix metal replacement (if there is any) , and on the basis of it we draw the conclusion on the measure of ion current can be expected after implantation. If the measured potential happenly gets on the activ part of the anode-polarization curve, than the chosen alloy must be eliminated from the sortiment of alloys of metal replacement of implantation.come into question. We must choose that metal alley from the other ones, to be implantated, which changes the yoltage-terms of the organism the least, and doesn't lead to ion precipitation inducing allergy, that means it stays passive after implantation in the organism.

The block-scheme of the equipment used for execution of the process according to the above written^" invention is shown in Fig.1. The part surrounded by ragged line is the electronic unit, which is built in an instrument box. A specially constructed probe, which is used for voltage measuring can be connected to this electronic unit (Fig.5.) , and a reference potential securing probe, which is used for measuring electrode potential (Fig.2.), and a feeler probe (Fig.3.) .

A set of specimen belongs also to the equipment, each part of it is constructed according to Fig.6., but each of them is made of different kind of metal replacement materials. The reference probe 2 and feeler probe 3 are used for measuring electrode potential. The reference probe 2 consists of a hollow insulating shaft 29, a cup, which can be hermetically locked on the top 30, a hygroscopic material, which can be put int the open bottom of the shaft 24, cotton-wool as an example, as electrolyte inside the shaft 25, suitably refere ce synthetic saliva, a silver- and silverchlorid/electrode of the second kiniF^e7^s:Lrιs in the electrolyte 28, which are linked by a metal thread 26 outside the shaft and a plug 27 with one of the inputs of the instrumental amplifier 12 of electronic unit 1.

The feeler electrode 3 is a probe, ending in a metal peak 32 which is supplied with insulating shaft 31 , it is linked by a metal thread 33 through a plug 34 with the other input of the instrumental amplifier 12 of the electronic unit 1. The current measuring probe 5 consists of an insulating shaft 51 , 2 pieces of platinum feeler situating near each other on one end of the shaft and ending in platinum sphere 5 which are connected by a metal thread 53 through plugs 54 with the current-voltage converter 11 of the electronic unit 1.

The current-voltage converter 11 in the electronic unit and an output of the instrumental amplifier 12 sensing voltage to be measured are connected to the input of the precision rectifier 13, on the output thereof is a thermo- compensated logarithmic amplifier 14, connected, and on the output of this a voltage-current converter 15 is connected, which drives an analogous indicator, sutably a Deprez-instrument 16. On the output of the logarithmical amplifier 14 is connected one of the inputs of the comparator, which drives a sound detector and a flash signal appliance, and on the other input thereof a reference voltage source is connected. The metal feeler peak 32 of the feeler probe 3 is- constructed so, that the suitably constructed specimen 6 can be slid on it, which metallic contacts with the metal feeler peak 32. 5 The supply of the instrument is secured by a voltage source of 9V 17, but it can be operated from the network with proper mains adapter.

After switching on the supply voltage, the instrument is in good working condition. Current measuring is possible

_ 10_ b_y _th_e curren_t. measuri•ng proeblee,ct/rode potmeenatsiuarling s possible by the reference and feeler probe. During measurement-we measure either voltage, or current.

The voltage arriving on the input of the instrument is sensed by the instrumental amplifier 12, current will be 15 traπ≡formed also to voltage, by current-voltage converter 11.

This voltage gets to the input of the precision rectifier 13, the task of it is to secure the polarity-independent measurement.

The polarity of voltage-measurement is indicated by LED 23, 0 with the help of comparator 22.

The rectified voltage gets to the voltage-current converter

15 which drives the indicator, through the logarithmical amplifier 14.

The logarithmical amplifier 14 secures the current to be 5 measured, respectively, it secures the measurement of voltage in one measuring range.

Hereby it becomes unnecessary the complicated manual, or automatical change of measuring range which is more complicated circuitly. 0 The Deprez-instrument 16 can be read more easily by the dentist, namely it is more important to sense the changing during measurement, than the punctual indication of voltage- and current values. By setting in the reference voltage-source connected to the input of the comparator 18 a value can be set in, that in case of overflowing it, the dentist will be warned by a sound detector and flash signal appliance connected to the output of the comparator.

Especially the sound signal means a great help for the diagnosticating doctor, because he can pay his attention to the placing of the probe.

We can summerize the advantageous effects of the application of instrument and process according to present invention as follows:

By present process ion-migrations, inducing allergic symptoms can be cleared up in vivo, in contradiction with processes known up-till-now, metal replacements which induce ion-migrations, respectively the metal component in their metal alloys which is responsible for allergy.

By changing of the very active metal replacement, the patient can be cured in a very short time, and by eliminating the allergen metal component, the metal-replacement-alloys inducing allergy can be also eliminated in the future. The equipment according to present invention is considerably orientated to the task, that means, it suits to the requirements of special medical tasks. It can be simply handled, it doesn't need switch either in measurement limit, or in working mode.

The special advantage of the equipment with sound singing is, that the dentist is not obliged to share his attention while using it, but he must concentrate only on the right placing of the probe.

Claims

1. Process for examination electro-chemical effects inducing inflammation and allergic symptoms in living organism, which are induced by implantation made of two or more metals in the living organism, during the process the electrode-potentials of implantated metal replacements are measured, characterized in that we compare the measured electrode-potential values with the anode-polarization curves given to the alloys of metal replacements and on the basis of it we can conclude to the rate of corrosion of certain metal replacements.

2. Process as claimed in Claim 1, characterized in that beside electrode-potential measurement we measure "in vivo" also ion currents, has been induced by potential difference.

3. Process as claimed in Claims 1. or 2. characterized in that we measure "in vivo" electrode potentials among metal replacements, which get into electro-chemical interaction with each other or with metal implantations to be implantated arid/or already implantated, in that way, that we touch specim made of the same material as of the metal replacements to be implantated, to the receiving tissue, and we measure the electrode-potential on the specimen touched to the tissue, or on another similar specimen, or on an implantated metal replacement. ^'

4. Equipment, especially used for the execution as claimed in Claims 1 to 3 , which consists of an electronic unit and probes, characterized in, that it is specially constructed, it is suitable for measuring electrode-potential and current, it is connected by lead in the electronic unit, it is supplied with probes (2,3,5) , in the electronic unit 1 there are: a current-voltage converter 11 sensing the current to be measured, an instrumental amplifier 12 sensing the voltage to be measured, a precision rectifier 13, connected by its input with the output of the before mentioned parts, in given cases, a logarithmic amplifier 14 is connected on the output of the precision rectifier 13, on the latter one, suitably an analogous indicator, a voltage-current converter 15 is connected, which drives especially Deprez-instrument 16.

5. Equipment as claimed in Claim 4. characterized in that on the output of the suitably logarithmic amplifier 14 in the electronic, unit 1 is connected with one of the inputs of comparator 18 which drives a sound detector 20 and/or a flash signal 21, while the other input of the comparator 18 is connected with a reference voltage source. 19.

6. Equipment as claimed in Claims 4. or 5. characterized in that the reference probe 2 used for measuring electrode-

-potential , which consists of a hollow insulating shaft 29, a cup hermetically locked on the top 3_.0, a hygroscopic material, which can be put in the open bottom of the shaft 24, an electrolyte inside the shaft 25, suitably synthetic saliva, / --Yectrode of second k

into electrolyte, especially silver-silverchloride 28, and together with the feeler probe 3 it is connected by metal thread with the electronic unit 1.

7. Equipment as claimed in Claim 6. characterized in that platinum hemispheres 52 are fastened to the end of measuring peak of the current-measuring probe, and they are connected by a metal thread 53 with the electronic unit 1.

8. Equipment as claimed in any of Claims 4 to 7 characterize in that it is equipped with a set of specimen 6 made of available materials of metal replacements.

9. Equipment as claimed in Claim 7. characterized in that the specimen 6 seat on the measuring peak 32 of the feeler probe-3 and it can be plugged in.