Apparatus for positioning the head of a patient for producing x-ray pictures

• US 4,831,645 A
• Filed: 09/23/1987
• Issued: 05/16/1989
• Est. Priority Date: 09/26/1986
• Status: Expired due to Term

• Current Assignee: Sirona Dental Systems GmbH (Sirona Dental Systems Incorporated)
• Original Assignee: Siemens AG
• Inventors: Guenther, Werner, Heubeck, Erich, Muether, Manfred
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Freeman, John C.
• Application Number:
  US07/100,221
• Time in Patent Office: 601 Days
• Field of Search: 378/38, 378/99, 378/205-206, 358/111
• US Class Current: 378/205
• CPC Class Codes: A61B 5/1077 Measuring of profiles
• CPC Class Codes: A61B 6/08 Auxiliary means for directing the radiation beam to a particular spot, e.g. using light beams
• CPC Class Codes: A61B 6/51 for dentistry

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.

Claims

1. In an apparatus for positioning the head of a patient while producing an x-ray picture of a jaw of a patient including a dental panorama tomogram, said apparatus having a source of x-rays or projecting x-rays along a path having a central ray and said apparatus having means for receiving the x-rays, said apparatus further including means for positioning the head of the patient in a desired position relative to a fixed first point with respect to at least one projection plane, said fixed first point, in turn, assuming a definite position relative to the central ray of the source of x-rays, the improvements comprising said means for positioning the head of the patient having a bite-down member for the front teeth of the patient and said fixed first point lies in the region of the front teeth engaged on the bite-down member, means for registering silhouettes of the head of the patient whose front teeth are engaging said bite down member and projection means for portraying the silhouette of the patient in a plane parallel to the projection plane, said projection means having means to portray a first silhouette of the head of the patient in an actual position relative to the fixed first point and said projection means having means to create a second silhouette of the head of the patient in a desired position relative to the fixed first point from said first silhouette of the head of the patient in the actual position and said projection means having means to portray said first and second silhouettes simultaneously by superimposing said first and second silhouettes on top of one another so that the projection of the fixed first point and the central ray belonging to both of said first and second silhouettes essentially coincide.

2. In an apparatus for positioning the head of a patient while producing an x-ray picture of a jaw of a patient including a dental panorama tomogram, said apparatus having a source of x-rays for projecting x-rays along a path having a central ray and said apparatus having means for receiving the x-rays, said apparatus further including means for positioning the head of the patient in a desired position relative to a fixed first point with respect to at least one projection plane, said fixed first point, in turn, assuming a definite position relative to the central ray of the source of x-rays, the improvemets comprising said means for positioning the head of the patient having a bite-down member for the front teeth of the patient and said fixed first point lies in the region of the front teeth engaged on the bite-down member, means for registering silhouettes of the head of the patient whose front teeth are engaging said bite down member and projection means for portraying the silhouette of the patient in a plane parallel to the projection plane, said projection means having means to portray a first silhouette of the head of the patient in an actual position relative to the fixed first point and said projection means having means to create a second silhouette of the head of the patient in a desired position relative to the fixed first point with the portraying of said first and second silhouettes being superimposed on top of one another so that the projection of the fixed first point and the central ray belonging to both of said first and second silhouettes essentially coincide, said means for registering said first and second silhouettes of the head of the patient being formed by a video camera, said projection means for portraying said first and second silhouettes of the head being formed by a television monitor, and image storage and an image processing means, said video camera having an optical axis extending at right angles relative to the projection plane to register a first silhouette of the head of the patient, said image processing means and image storage creating a second silhouette of the desired position relative to the fixed first point from the first silhouette of the actual position, and said monitor simultaneously portraying the second silhouette with the first silhouette.

3. In an apparatus according to claim 2, wherein said image processing means is arranged between said video camera and said image storage.

4. In an apparatus according to claim 3, wherein said video camera directly supplies a digital video signal, said image processing means is formed by a digital computer and said image storage is formed by a digital memory.

5. In an apparatus according to claim 4, wherein said video camera is a CCD video camera.

6. In an apparatus according to claim 2, wherein said image processing means allocates a gray scale value or color value to the silhouette of the head of the patient in the desired position relative to the fixed first point, which desired position is derived from a silhouette of the actual position relative to said fixed point.

7. In an apparatus according to claim 2, wherein said video camera is optionally positionable so that said optical axis proceeds perpendicular to a second projection plane, said second projection plane forming an angle, with said first mentioned projection plane.

8. In an apparatus according to claim 2, wherein a second video camera is provided, said second video camera having an optical axis extending perpendicular to a second projection plane and said second projection plane forming an angle with said first mentioned projection plane.

9. In an apparatus for positioning the head of a patient while producing an x-ray picture of a jaw of a patient and including a dental panorama tomogram, said apparatus having a source of x-rays for projecting x-rays along a path having a central ray and said apparatus having means for receiving said x-rays, said apparatus further including means for positioning the head of the patient in a desired position relative to a fixed first point with respect to at least one projection plane, said fixed first point, in turn, assuming a definite position relative to the central ray of the x-ray tube, the improvements comprising means for registering first and second silhouettes of the head of the patient and projection means for portraying said first and second silhouettes of the patient in a plane parallel to the projection plane, said means for registering said first and second silhouettes of the head, comprises a video camera having an optical axis extending at right angles relative to the projection plane to register said first silhouette of the head of the patient, said projection means being capable of simultaneously portraying said first silhouette of the head of the patient in an actual position relative to the fixed first point and said second silhouette of the head of the patient in a desired position relative to the fixed first point with the portraying of said first and second silhouettes being superimposed on top of one another, said projection means including a television monitor, an image storage, and an image processing means, said image processing means creating said second silhouette of the desired position from said first silhouette of the actual position, and said television monitor simultaneously portraying said first silhouette of the actual position and said second silhouette of the desired position so that the projection of the fixed first point and the central ray belonging to both silhouettes essentially coincide.

10. In an apparatus according to claim 9, wherein said image processing means is arranged between said video camera and said image storage.

11. In an apparatus according to claim 10, wherein said video camera directly supplies a digital video signal and said image processing means is formed by a digital computer and said image storage is formed by a digital memory.

12. In an apparatus according to claim 11, wherein said video camera is a CCD video camera.

13. In an apparatus according to claim 9, wherein said image processing means allocates a gray scale or color value to said second silhouette of the head of the patient in its desired position relative to the fixed point, which deviates from a color value or gray scale value of said first silhouette of the actual position relative thereto.

14. In an apparatus according to claim 9, wherein said video camera is optionally positionable in a second position, with said video camera having an optical axis extending perpendicular to a second projection plane, said second projection plane extending at an angle relative to said first-mentioned projection plane.

15. In an apparatus according to claim 9, which includes a second video camera having an optical axis extending perpendicular to a second projection plane, said second projection plane forming an angle with said first-mentioned plane, said second video camera having a second monitor with a second iamge storage and image processing means so that the images of said second video camera can be displayed simultaneously on the second monitor with the images of said first-mentioned camera on said first monitor.