Abstract: A method and apparatus for non-invasive analysing the structure and chemical composition of bone tissue eliminating the influence of surrounding tissues, is provided. The method consists in using a system of at least four electrodes (1, 2, 3, 4, 5, 6, 7, 8) placed in electrical contact with tissues surrounding the analysed bone, preferably a long bone to establish screening potential distribution using screening electrodes (7, 8). Measuring current injecting electrodes (1, 2) are used to force the measuring current flow through the internal part of the analysed bone. At the same time the screening electrodes (7, 8) reduce the measuring current flow through the tissues surrounding the analysed bone almost to zero. Then measuring current and potential at the measuring current injecting electrodes (1, 2) as well as phase difference between potential at measuring current injecting electrodes (1, 2) and measuring current are measured.

Abstract: Method for Controlling Electrodes for Bio-impedance Measurements and Apparatus for Bio-impedance Measurements There is provided a control circuit for electrodes in a bio-impedance measurement system, the bio-impedance measurement system comprising screening current injecting electrodes and measuring current injecting electrodes, the control circuit comprising: a current generator for connection to at least one screening current injecting electrode; and an measuring signal output configured to establish a measuring potential between the measuring current injecting electrodes, wherein the control circuit is configured such that the measuring potential is dependent on a measure of a potential difference resulting from the screening current. The control circuit uses the value of the potential resulting from the screening current to determine the potential difference between the measuring current injecting electrodes.

Abstract: A secondary caries detection device includes a current generating device configured to generate a current having the form of a sinusoidally varying signal with a frequency chosen from the range of frequencies from 200 Hz to 100 kHz and a chosen amplitude from the range of 50 mV to 5 V. The secondary caries detection device also includes a plurality of preamplifiers of high sensitivity and linearity with phase-sensitive measuring components sensitive to the chosen frequency and integral multiples of the chosen frequency. The secondary caries detection device further includes a microprocessor control unit connected to the current generating device and the plurality of preamplifiers.

Abstract: Method for Controlling Electrodes for Bio-impedance Measurements and Apparatus for Bio-impedance Measurements There is provided a control circuit for electrodes in a bio-impedance measurement system, the bio-impedance measurement system comprising screening current injecting electrodes and measuring current injecting electrodes, the control circuit comprising: a current generator for connection to at least one screening current injecting electrode; and an measuring signal output configured to establish a measuring potential between the measuring current injecting electrodes, wherein the control circuit is configured such that the measuring potential is dependent on a measure of a potential difference resulting from the screening current. The control circuit uses the value of the potential resulting from the screening current to determine the potential difference between the measuring current injecting electrodes.

Abstract: A device for secondary caries detection characterized in that it contains a current generating block in its casing (6), advantageously equipped with the high linearity amplifiers, the current having the form of sinusoidally varying signal, advantageously with one frequency chosen from the range of frequencies from 200 Hz to 100 kHz and amplitude from 50 mV to 5 V; a block of preamplifiers (4), advantageously of high sensitivity and linearity with phase-sensitive detectors measuring components, advantageously with one frequency chosen from the range of frequencies from 200 Hz to 100 kHz as well as its multiples, advantageously integral in principle; microprocessor control unit (5), advantageously with a miniature keyboard and display unit, and at least one fixed electrode (2) placed on mucous membrane of the oral cavity and at least one moveable electrode to be mounted on a tooth (1).

Abstract: A method and apparatus for non-invasive analysing the structure and chemical composition of bone tissue eliminating the influence of surrounding tissues, is provided. The method consists in using a system of at least four electrodes (1, 2, 3, 4, 5, 6, 7, 8) placed in electrical contact with tissues surrounding the analysed bone, preferably a long bone to establish screening potential distribution using screening electrodes (7, 8). Measuring current injecting electrodes (1, 2) are used to force the measuring current flow through the internal part of the analysed bone. At the same time the screening electrodes (7, 8) reduce the measuring current flow through the tissues surrounding the analysed bone almost to zero. Then measuring current and potential at the measuring current injecting electrodes (1, 2) as well as phase difference between potential at measuring current injecting electrodes (1, 2) and measuring current are measured.

Abstract: The method for obtaining copper powders and nanopowders from industrial electrolytes including waste industrial electrolytes through electrochemical deposition of metallic copper on a cathode consists in using potentiostatic pulse electrolysis without the current direction change or with the current direction change, using the cathode potential value close to the plateau or on the plateau of the current voltage curve on which the plateau of the current potential range is from ?0.2 V÷?1 V, and a moveable or static ultramicroelectrode or an array of ultramicroelectrodes made of gold, platinum or stainless steel wire or foil is used as a cathode, whereas metallic copper is used as an anode and the process is carried out at temperature from 18-60° C., and the electrolysis lasts from 0.005 to 60 s. Said method can be used to obtain nanopowders and powders characterised by particle structure and dimension repeatability and purity from 99%+ to 99.

Abstract: There is described an electrode assembly for passing electrical current through at least part of a tooth, the assembly comprising: an electrode holder; and a plurality of resilient projecting elements coupled to the holder, each element comprising one or more electrodes, the assembly being arranged in use such that when the assembly is positioned adjacent a tooth, the electrodes contact respective parts of at least one surface of the tooth. The assembly is preferably for use in A.C. impedance spectroscopy for caries detection and monitoring.

Abstract: There is described a method o monitoring the structure of a tooth comprising:—placing an electrode carrier, having at least three electrodes, adjacent the tooth such that the electrodes contact at least one of the occlusal, approximal or free smooth surfaces of the tooth; selecting pairs of the carrier electrodes, one electrode of each selected pair to act as a contact electrode, and the other as a counter electrode; for each selected pair of electrodes, passing an alternating electrical current between the electrodes so as to form a circuit from the electrodes and a respective part of the tooth at least between the electrodes, and monitoring the electrical response for the circuit; and processing the monitored response for each pair of electrodes so as to determine structural information relating to the respective parts of the tooth. Apparatus for carrying out the method is described. The method is preferably an impedance spectroscopy technique, for caries detection and monitoring.

Abstract: The method consists in registering curves by cyclic voltammetry method in the range of copper ion concentration up to 20 g/l or alternately by chronoamperometric method in the range of concentration from 20 to 60 g/l. A platinum or gold microprobe of a diameter in the range from 1 to 50 um and a copper plate reference electrode are used. The value of current density read off from said curves is compared to the calibration curves previously determined by standard additions method. For high concentration in the range from 20 to 60 g/l the calibration curves obtained in the range of temperatures from 15 to 60° C. are registered.

Abstract: The present invention is directed to a method and apparatus for the detection of dental caries. The method comprises the steps of placing at least one probe electrode in electrical contact with a surface of a patient's tooth, placing a second electrode in electrical contact with another part of the body of the patient, passing an alternating electrical current between said probe and second electrodes, and measuring the electrical impedance between the electrodes.