Abstract: An apparatus for positioning the head of a patient for producing dental panorama tomograms, which apparatus has an arrangement for positioning the head in a desired position relative to a fixed point with respect to at least one projection plane and this point, in turn, assumes a definite position relative to a central ray extending from the x-ray tube towards the x-ray picture, characterized by an arrangement for producing silhouettes and for projecting the silhouettes of the head in an actual position and in a desired position, simultaneously with the fixed point of each of the two silhouettes coinciding. By moving the head forming the silhouette of the actual position, the silhouette of the actual position can be moved to be congruent with the silhouette of the desired position to bring the head into the desired position for x-ray exposure.

Abstract: An X-ray examination apparatus, for example, for dental use, comprises an extraoral radiation entrance screen which is displaceable in a plane which is transverse with respect to a normal thereto. Consequently, distortion-free imaging can be performed for the entire set of teeth and the adjoining regions of the jaws.

Abstract: The invention relates to a method of and an apparatus for recording image information in panoramic X-ray photography. The total information contained in a beam of X-rays penetrated through an object is recorded on a memory disc, whose configuration is substantially the same as that of an object to be imaged, such as a dental arch, said memory disc being kept stationary during the filming relative to the object to be imaged. The memory disc is used for producing or presenting layerwise reproduced images of desired layers. The preparation of reproduced images from the memory disc can be performed on a principle corresponding to conventional panoramic tomography with the exception that the object to be imaged is a memory disc.

Abstract: The invention relates to a method of photographing a desired object with a panoramic X-ray apparatus fitted with automatic exposure, comprising an X-ray generator (4, 5), an X-ray tube (5) and a film (7) with its holder. In the method, the detection of a cone of rays (9) penetrated through an object is effected before the actual filming is started and, after the detection, the filming is effected by using a cone of rays (6), directed so as to bypass a detector (1).

Abstract: A dental diagnostic apparatus or installation which obtains a better matching of the exposure data to the patient and has a rotary unit carrying the radiation source and the film cassette which are adjustable to an initial position by an adjustment arrangement and from this initial position the film cassette can be charged with the radiation within the framework of normal transillumination with the radiation initially beginning outside of the mandibular arch. The incoming radiation dose is measured by a detector arrangement which creates a signal that is compared in a computational unit of a control arrangement to a rated quantity corresponding to a prescribed dose value. The exposure data required from further transillumination of the patient's head are identified therefrom and the tomogram position is determined by identifying the patient-associated film speed via the jaw length/jaw width measurements and comparison to defined rated value.

Abstract: In order to provide a dental X-ray diagnostic installation for producing panoramic tomograms of the jaw of the patient and to achieve a simple structure with improved image quality, the apparatus includes an adjustment mechanism for the carrier of the radiation source and the film cassette holder to be adjusted in an orbital curve corresponding to the dental arch of the patient. The adjustment arrangement includes first adjustment parts with which the carrier can be rotated around a first vertical axis, and second adjustment elements for moving or swivelling the first axis in an arch transverse relative to the symmetry axis of the subject during the rotary motion. The swivel radius and the amount of excursion of this swivel motion are selected so that the perpendicular transillumination direction through the subject gives a constant distance between the subject and the film during the motion of the rotary unit. To accomplish this, the invention includes two separate embodiments with various modifications.

Abstract: A dental X-ray diagnostic installation for producing panoramic tomograms of the jaw of a patient is provided with a multiple diaphragm part having a plurality of different diaphragm apertures which can be adjusted to be positioned into a beam path from the X-ray source to enable producing different exposures. Preferably, the multiple diaphragm part is mounted for rotation on an axis so that the diaphragm apertures can be respectively aligned to the beam path of the radiation source. The multiple diaphragm part can be either a one-piece diaphragm member having a cylindrical configuration, a multiple piece member having a disk configuration, or can be a box-shaped carrier carrying a plurality of diaphragm inserts.

Abstract: Panoramic tomography X-ray apparatus such as for obtaining images of dental systems, comprises a rotatably mounted arm to which the X-ray tube of an X-ray generator and an X-ray film cartridge, along with film transport equipment, are mounted, and a control system for controlling the functioning of the equipment of the apparatus on the basis of control data and a program pre-stored therein. A control system controls the speed of a rotary motion motor that rotates the arm, the speed of the film transport motor and the distribution of those speeds, independently of each other. In this manner, it is possible to photograph dental systems of varying sizes and shapes both sharply and with suitable exposure time. In addition to controlling the speeds of the rotary motion and film transport motors, the control system may also control the anode current and/or the anode voltage of the X-ray generator during the exposure sequence.

Abstract: In order to be able to produce congruent panoramic strip exposures of a jaw of a patient with a dental x-ray diagnostic installation, the patient's head must be positioned by means of a forehead support, which is adjustable only in a horizontal plane, and by means of a seating part which is rigidly arranged on a carrier in the device. The seating part contains an arrangement for forming a seating surface for engaging the upper jaw of the patient so that the seating surface engages a sub-nasal point of the jaw for those patients who have no teeth or only part of their teeth and a second seating type surface for those patients having a full set of teeth.

Abstract: A panoramic tomography X-ray apparatus comprises a fixed frame to which another rotary frame is suspended, the rotary frame having an X-ray tube at one end thereof and a film cartridge device for X-ray film at an opposite end thereof. Drive mechanism for turning the rotary frame in a substantially horizontal plane is provided, for taking a panoramic X-ray photograph. The drive mechanism comprise a drive and guide groove which has straight side sections and a curved section connecting the side sections together and a drive unit also comprising a drive wheel which, when rotated by the drive unit, turns the rotary frame. The rotary frame is suspended from the fixed frame by a crank mechanism which is joined to both the rotary frame and to the fixed frame through respective sets of bearings. The drive and guide mechanism along with the crank mechanism interact in such a manner that, in the front area of a dental arch, i.e.

Abstract: An apparatus for orthoradial panoramic tomography comprises a radiation source for motion relative to a point of reference; a cassette means also for motion relative to said point of reference; a support for holding said radiation source and said cassette relative to said point of reference; a head positioning means including a first or intraoral device and a second or extraoral device for positioning the patient's head relative to said point of reference; a carriage connected with said support 11 and including a grip; a substantially vertical column for slidingly holding said carriage in a vertically defined position and having a vertical axis distanced from said point of reference; the apparatus further comprises a foot positioning means having a substantially horizontal reference face for defining a vertical distance from said horizontal reference face to said point of reference and a substantially vertical reference face for maintaining toe and/or heel portions of the patient's feet in a predetermined pos

Abstract: An apparatus for panoramic X-ray photography of the area of the dentition and the jaws, comprising a frame part, a bearing part linearly movable in relation to the frame part, and a support arm attached rotatably to the bearing part, the arm having at one end an X-ray film and at the opposite end an X-ray source. The movements of the bearing part, the support arm and the film are synchronized in such a way that an image of an area of desired shape, e.g. the patient's dental arch, is obtained on the film. The invention provides a possibility, without shifting the patient, of altering the enlargement and, additionally of tilting the X-ray beam a desired angle in relation to the horizontal, whereby e.g. teeth oblique in relation to the vertical can be photographed more sharply.

Abstract: The invention relates to a patient support system in a narrow-beam tomographic X-ray apparatus, having a fixed frame fitted with a substantially vertical member (1), means (7, 8, 9) mounted on the frame for supporting a patient's head, said means being adapted to hold a patient's head (P) steady during the imaging session, as well as a bearer bar (3), fitted with a source of X-radiation (4) and imaging instruments (5) on the opposite sides relative to an object to be imaged and said bar being adapted in a known manner to perform rotational or combined rotational linear movement for scanning a predetermined layer to be imaged. In order to facilitate patient positioning and to secure proper positioning of a patient, said head support means (7, 8, 9) are set in a manner that the medial sagittal plane (S) of a patient supported thereby does not intersect said vertical frame member (1).

Abstract: An apparatus for panoramic X-ray photography of the area of the dentition and the jaws, comprising a frame part, a bearing part linearly movable in relation to the frame part, and a support arm attached rotatably to the bearing part, and having at one end an X-ray film and at the opposite end an X-ray source. The movements of the bearing part, the support arm and the film are synchronized in such a way that an image of an area of desired shape, e.g. the patient's dental arch, is obtained on the film. The invention provides the effect that the X-ray beam can be tilted to a desired angle in relation to the horizontal, whereby it is possible with greater sharpness to photograph, for example, teeth slanted in relation to the vertical. For this purpose, the support arm is tiltable about an axis perpendicular to its rotational axis so that, when this axis is vertical, the straight line connecting the source of radiation and the film is obligue to the horizontal.

Abstract: A collimator which is adapted to be mounted on the tube head cone of any existing panoramic X-ray machine used in dental examinations. The device personalizes the radiation from an X-ray machine to the size and shape of a patient's head by accurately allowing the X-rays to be directed only to that part of the head which requires the examination. The collimator of our invention comprises a housing which is mounted on the tube head cone of an X-ray machine, the housing having a vertical slot adapted to be aligned with the vertical slot in the X-ray tube head. A vertically-adjustable slide member regulates the open length of the slot in the housing, the slide member being regulated in its position by a pointer which extends from the slide and has an end disposed at a selected part of the patient's head. Thus, the length of the slot in the housing may be regulated to the shape of the patient's head to eliminate radiation to the eyes and retinal tissue, in the upper limit, and under the chin in the lower limit.

Abstract: Effective centers of rotation of the X-ray beams when projecting the anterior regions are caused to be disposed considerably more interiorly of the dental arch, i.e., farther from the incisors and closer to the X-ray source, to thus provide longer projection radii of the beams at the anterior region. Lengthening of the projection radii is achieved through unique velocity profiles of patient chair movement along an x-axis and film travel within the camera. The longer effective projection radii of beams at the anterior region provide for a substantially wider or thicker layer thereat with a concomitant modest narrowing of the layer at the canine regions.

Abstract: An exemplary embodiment comprises an exposure unit including an X-ray tube and a cassette holder rotatable about vertical axes and between which the head of the patient is disposed. A radiation detector is disposed at the cassette holder for supplying an electrical signal corresponding to the dose rate when it is struck by X-rays and being interconnected with an X-ray tube voltage controller and a dose rate regulator in such manner that the X-ray tube voltage is influenced by the output of the radiation detector to control the dose rate to a value producing an optimum film blackening. A function generator determining the speed of the exposure unit is provided in which a speed curve is stored given which the radiation dose influencing the film is approximately constant.

Abstract: This disclosure relates to a dental radiographic apparatus for photographing the entire jaws designed to control the rotation of a rotary arm such that the film surface of a film holder mounted at one end of the rotary arm may rotate and move substantially at equal speed substantially equidistantly along the dental arch and that the X-ray beams irradiated upon the film surface from an X-ray generator mounted at the other end of the arm may fall on the dental arch at any point thereof at right angles with the arch. The apparatus makes it possible to obtain a very clear tomographic picture of a curved plane of the entire jaws, the picture being free of a double image of the teeth, partial change in enlargement ratio of the image obtained, and partial difference in the shade of the image obtained.

Abstract: A dental x-ray diagnostic installation has an exposure unit consisting of an x-ray tube and a cassette holder for generating a dental x-ray exposure. The exposure unit is rotatable about a patient's head by a motor. A radiation detector is attached to the cassette holder which supplies an electrical signal corresponding to the radiation dose rate to a dose rate regulator which in turn operates a voltage control unit which sets the level of high voltage supplied to the x-ray tube such that the dose rate of the radiation emitted by the x-ray tube is maintained at a value for producing an optimum film exposure. A range adjustment for the x-ray tube voltage is externally selected and limits operation of the voltage control unit such that if the dose rate regulator supplies a signal to the voltage control unit requiring a voltage which exceeds the set limit, the voltage control unit is inhibited and instead the motor speed is adjusted to maintain the optimum exposure.

Abstract: A dental x-ray diagnostic installation comprises x-ray apparatus containing x-ray generator and x-ray tube having a hollow anode in the form of applicator for insertion in the interior of a patient's mouth. In order to facilitate the construction and handling of the apparatus in particular the insertion of the applicator in the mouth, the x-ray apparatus is designed as a unit capable of being positioned on a table or on a wall and contains a stationary member or part, which supports a horizontal axle which pivotably connects a housing containing the x-ray tube and the applicator on the stationary member for pivotable movement therewith. In addition, the installation includes a bite-on part which has a bite piece and a sleeve, which telescopically receives the applicator and enables the patient to locate the applicator in the desired position within the mouth.

Abstract: A digital dental system and method for real time display of a patient's dental image to detect changes with respect to at least one previous dental image of the patient. The system comprises an imaging unit for obtaining a real time dental image from the patient, a converter for converting the real time dental image to digital form, an input device for inputting further digital signals corresponding to at least one previous dental image of the patient, a processor for processing the digital signals and the further digital signals to develop corresponding display signals and further display signals, and a display unit and at least one further display unit for simultaneously and in real time displaying the dental image and the at least one previous dental image, respectively, of the patient. A preferred embodiment of the invention involves whole picture processing of the present and previous dental images to determine changes or differences therebetween.

Abstract: A flexible film cassette for holding a dental x-ray film on the outside of a patient's mouth for exposure from a radiation source from an x-ray diagnostic installation or device in which an applicator is capable of being inserted intraorally in the patient's mouth characterized by a first support extending between an applicator and the cassette and a second support spaced an interval from the axis of the first support for forming a coupling between the film and the housing of the x-ray device to prevent rotation of the cassette relative to the applicator.

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.