Abstract: The disclosure relates to an occlusion pressure sensor of the construction in which pressure sensitive block changing in electric characteristic under external pressure are arranged in multiple rows. The occlusion pressure sensor is designed to detect an electric signal responsive to occlusion pressure from the pressure sensitive blocks by successively and electrically scanning the blocks in the state of a patient engaging his teeth.

Abstract: A hanger arm mechanism to hold a lamp head vertically rotatably in dental lighting equipment is directed to a mechanism designed to rotate the lamp head around the axis shaftline of the hanger arm and to stop the same in a desired position, with the result that the field of lighting of the shadowless lamp mounted inside the lamp head can freely be changed in the range of rotation of the lamp head without making the patient turn his head.

Abstract: This disclosure relates to a control device of transmitting an ultrasonic pulse from an ultrasonic transmitter to an ultrasonic receiver by disposing the transmitter and the receiver between two movable members which are placed in a variable relation in linear distance with each other, converting aerial propagation time of the pulse from the transmitter to the receiver into an electrical means, memorizing and holding a distance between the two members by the electrical means, and reading the memorized distance at any desired time and reproducing the distance. The disclosure also relates to a control device using the system.

Abstract: Improvements in a treatment chair whose backrest frame is designed to be tiltable with respect to the seat frame of the chair by use of a roller rotating within a guide groove are disclosed. In the disclosed embodiments all utilize an arc segment portion groove. As a result, the top portion of the backrest frame holds substantially the same peripheral speed throughout travels with raising and lowering of the backrest frame and the patient resting against the backrest frame is thereby free from any uncomfortable feeling due to preceptible changes in peripheral speed during the rise and fall movement of the frame.

Abstract: This device feeds back an output proportional to the electric current flowing through an X-ray tube to a filament current controlling means, reads out a difference between the increase and decrease in the current of the X-ray tube made by the effect of charge on the wall of the X-ray tube, and constantly stabilizes the current in the tube at the optimum value by increasing and decreasing a filament current in response to the difference read out.

Abstract: This disclosure relates to an X-ray photographing apparatus both for photographing the entire jaws and for cephalographic use. The apparatus is constructed in such a manner that, in setting the generator in any direction either for cephalographic use or for use in photographing the entire jaws, the X-ray generator is automatically vertically rotated through a specified angle and is enabled to make simple and correct change in the direction of irradiation by providing the X-ray generator mounted horizontally and vertically rotatably at one end of a rotary arm with a sliding element, providing the arm with an inclined guide groove for guiding the element therein, and merely rotating the generator horizontally through a specified angle.

Abstract: The disclosure relates to improvements in a cordless handpiece for dental treatment having storage batteries and an electric motor incorporated therein. The improvements are that the cutting tool is increased in cutting performance and that the replacement of a contra angle and a straight tool has been facilitated.

Abstract: A device for making it possible to visually provide a thorough knowledge of the activities of the masticatory muscles by optically measuring and displaying the EMG potential of the masticatory muscles at the time of matication for use in correcting abnormal and unbalance occlusion patterns. The device comprises a plurality of sets of electrodes (8) and (9) each set consisting of a pair of right and left electrodes, said electrodes being designed to be attached to the surfaces of the masseter and temporal muscles in both sides so as to detect electromyographic potentials in time of mastication, a means (A) for converting the electromyographic potentials detected by said electrodes (8) and (9) respectively into electrical signals for display, a display means (C) for selectively energizing said means (C) in response to the signal, the means (C) including display lines (L.sub.1) and (L.sub.2) of light-emitting members (12) and (13) which are independent of one another for each of the electrodes (8) and (9).

Abstract: A headrest control device for a treatment chair in which the headrest contains a linkage capable of raising and lowering a head supporting portion of the headrest in synchronized interlocking relationship with the tilting of the headrest. The device facilitates the bringing of the head supporting portion into firm contact with the rear neck region of the patient thereby making it possible for him to open his mouth in a natural posture when he undergoes oral treatment with the backrest of the treatment chair being held approximately horizontal and the headrest being slightly forwardly tilted.

Abstract: According to this invention, useless exposure of a human being to X-ray is avoided and X-ray film is economically used by providing the X-ray generator of a dental X-ray apparatus with an X-ray intercepting means by which the size of the opening or slit for X-ray beams flow is easily controlled. The X-ray apparatus comprises an X-ray generator, an X-ray film, an arm for supporting the X-ray generator and the X-ray film in such a manner that the X-ray generator faces the X-ray film. When the arm is rotated at a predetermined angle around the X-ray film thereby causing the X-ray generator to be rotated proportionally, the X-ray generator emits X-ray beams through the vertically elongated slit disposed in the X-ray generator's head.

Abstract: The disclosure relates to an X-ray photographic apparatus which can prevent the overshoot of the tube current, which is apt to generate at the start of X-ray radiation. The apparatus comprises an integration capacitor which is charged by the preset preheating level setting voltage during the preheating period, an integration circuit which integrates the difference between the reference voltage and the detection voltage corresponding to the X-ray tube current during the X-ray radiation and a filament heating current control circuit driven by said integration circuit.

Abstract: The disclosure relates to a dental radiographic apparatus for photographing the entire jaws having a rotary arm including an X-ray generator disposed in an opposed relation with an X-ray film feed means. The apparatus includes a means for detecting electrically the shape and characteristics of an object through the position of the rotary arm rotated and a means for automatically controlling the rotation speed of the arm and the feed speed of an X-ray film in response to the detection signal generated by the electrical detection means, whereby it is intended to provide a clear and sharp X-ray photographic image free from distortion, uniform in density and optional in rate of enlargement.

Abstract: An overcurrent protection circuit of an inverter supplied with power through a switching regulator which has the basic features of the circuit constructed in such a manner that, when the input current of the inverter exceeds a set point, the circuit forcefully energizes conduction circuits of two systems including PUT or UJT through a pulse generation circuit (turn-on circuit) connected to the switching regulator and instantaneously shuts off the overcurrent of the inverter and a driving signal of the switching regulator.

Abstract: An automatic blackening degree adjustment system which includes the steps of making a fluorescent plate luminous by a residual dose of X-rays that have penetrated the person to be photographed and an X-ray film, converting the amount of luminescense into electric output, converting the relative feed speed of an X-ray film with respect to an X-ray beam into electric output and computing an electric output obtained from the conversion of amount of luminescense and the relative feed speed and feeding back a value obtained to a filament control circuit to thereby control the filament current of the X-ray machine whereby the tube voltage of the X-ray tube is kept constant so that the exposure is adjusted to an optimum amount with the X-ray wave length kept constant and resulting in X-ray photograph taken which have sufficient and uniform contrast in any part thereof.

Abstract: An improved dental handpiece holder supports a handpiece in the region from the rear end of the grip portion to the tail-stock portion. A front gripping holder portion prevents movement in the horizontal direction, a rear gripping holder portion prevents a forward tipping moving, and the front and rear gripping portions co-act to prevent movement of the handpiece in the axial direction. The front gripping portion is provided with three separate portions, one on the left hand wall and two on its right hand wall. The two supporting portions on the right hand wall are spaced axially apart from one another, and the single supporting portion on the left hand wall is located in a axial position intermediate that of the opposing two portions. Right and left supporting portions in the rear gripping portion support the tail-stock of the handpiece.

Abstract: This invention relates to a dental handpiece including turbine blades to be driven by a high-speed fluid under pressure to a turbine rotor chucking a cutting shaft, and blades are provided with openings or cutout portions located at both outside ends in a thrust direction of the blades so as to provide flange portions between the openings and the end portions of the blades and the peripheral width of the blades is larger than that of the high-speed fluid supply apperture.

Abstract: The disclosure relates to a system of automatically controlling the distance between two members placed in a relatively variable relation with each other with respect to distance on a straight line. One of the two members is provided with a transmitter capable of generating an ultrasonic pulse excellent both in directivity and in damping characteristics, and the other is provided with a receiver with the same in characteristics as the transmitter and which is disposed in an opposed relation with respect to the transmitter. The distance between the two members is automatically controlled by causing an ultrasonic pulse to be transmitted and received respectively by the transmitter and the receiver.

Abstract: The disclosure relates to a system for aerially transmitting an ultrasonic view of a vibration mode, small in angle of direction, in a clear state and to a transmitter and a receiver used in the system. According to the system, an ultrasonic pulse can be used for distance measurement, control and other signal means even at relatively short distance.

Abstract: This disclosure relates to an assembly for paired face to face dental trainees designed to permit two trainees to receive training in dental treatment by seating them in an opposed relation with each other with the desk placed therebetween. The assembly is greatly contributable to a reduction in space, cost in that it comprises human head models and freely drawable and retractable instruments symmetrically mounted in the front and rear side of the desk assembly, drawing and retraction devices for the instruments housed in the upper and lower layers in the desk, a control unit and a piping unit each for a supply fluid housed in the desk, and side boxes attached to the same side on the front and the rear side of the desk and adapted to store treatment tools, utensils and the like therein.

Abstract: A dental treatment system comprising a treatment chair seat, a backrest mounted tiltably thereto, and a headrest characterized in that the device includes a unit box assembly adapted to be stored inside or underside the backrest and to be drawn out therefrom. The unit box assembly having a variety of instruments housed therein is designed such that the instruments may be positioned in the space on the shoulder of the backrest or on the side of the headrest or on both of the shoulder and the side because of the construction of the assembly that, when the box assembly is stored in the backrest, it may be interlocked with the tilting of the backrest and, when drawn out therefrom, may be freely moved, stopped, vertically and bilaterally rotated and stopped independently of tilting the backrest to thereby facilitate handling of the instruments and to save additional space for separate arrangement of instruments.