Dental x-ray aligning system

• US 4,223,228 A
• Filed: 06/21/1979
• Issued: 09/16/1980
• Est. Priority Date: 06/21/1979
• Status: Expired due to Term

• Current Assignee: Indianapolis Center for Advanced Research, Inc.
• Original Assignee: Indianapolis Center for Advanced Research, Inc.
• Inventors: Kaplan, Jerome I.
• Primary Examiner(s): Church, Craig E.
• Application Number:
  US06/050,705
• Time in Patent Office: 453 Days
• Field of Search: 250/491, 250/401, 250/402, 250/416 R
• US Class Current: 378/205
• 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 6/512 Intraoral means
• CPC Class Codes: H01J 35/02 Details

Abstract

A dental x-ray aligning system in which various Hall effect sensors, mounted on a dental x-ray apparatus, detect the magnetic field strength resulting from a magnet which is attached to an x-ray film plate located within the mouth of a patient. By measuring and comparing the relative magnetic field strengths, the present invention can indicate when the dental x-ray apparatus is properly aligned, and can also indicate the direction in which the apparatus should be moved to obtain alignment, and the distance between the apparatus and the film plate. The present invention also includes means for adjusting the collimation of the dental x-ray apparatus.

Claims

1. A dental x-ray aligning system for aiming a dental x-ray apparatus at an x-ray film plate comprising:

a. a magnet;

b. magnet positioning means for maintaining said magnet in a fixed relation with an x-ray film plate;

c. at least three Hall effect probes;

d. probe positioning means for maintaining said Hall effect probes in fixed relation to the dental x-ray apparatus;

e. current means for passing a specific current through said Hall effect probes;

f. detection means for detecting and measuring the Hall effect voltage potentials of said probes; and

g. indicator means for comparing the detected Hall effect voltage potentials of said probes and for indicating alignment of the dental x-ray apparatus with the x-ray film plate.

2. The dental x-ray aligning system of claim 1 in which said indicator means additionally includes direction means for indicating the direction in which the x-ray apparatus should be moved in order to align the dental x-ray apparatus with the x-ray film plate.

3. The dental x-ray aligning system of claim 1 in which said indicator means additionally includes rangefinder means for indicating the distance from the dental x-ray apparatus to the x-ray film plate.

4. The dental x-ray aligning system of claim 3 additionally comprising:

h. collimation means for adjusting the x-ray beam size of the dental x-ray apparatus.

5. The dental x-ray aligning system of claim 1 in which said magnet is a permanent magnet of samarium cobalt.

6. The dental x-ray aligning system of claim 1 in which said magnet positioning means comprises a container attached to the central back portion of the x-ray film plate.

7. The dental x-ray aligning system of claim 1 in which the magnet positioning means maintains said magnet in a position such that the north-south polar axis of said magnet is perpendicular to the x-ray film plate.

8. The dental x-ray aligning system of claim 1 additionally comprising:

i. means for maintaining the x-ray film plate in fixed relation to a tooth within the mouth of a patient, said means including a tab which projects perpendicularly from the x-ray film plate.

9. The dental x-ray aligning system of claim 1 in which said plurality of Hall effect probes includes a first set of probes and a second set of probes and in which said probe positioning means maintains said Hall effect probes such that:

a. said first set of probes are approximately equally angularly spaced along the circumference of a first circle, which is perpendicular to an x-ray beam emitted from the dental x-ray apparatus.

b. said second set of probes are approximately equally angularly spaced along the circumference of a second circle which is spaced a distance away from said first circle.

c. said first circle and said second circle have about the same radius.

10. The dental x-ray aligning system of claim 1 in which said Hall effect probes include strips of electrically conductive material and said probe positioning means maintains said probes such that the plane defined by the surface of each said probe is substantially parallel to an x-ray beam emitted from the dental x-ray apparatus.

11. The dental x-ray aligning system of claim 9 in which said Hall effect probes include strips of electrically conductive material and said probe positioning means maintains said probes such that the plane defined by the surface of each said probe is substantially parallel to an x-ray beam emitted from the dental x-ray apparatus.

12. The dental x-ray aligning system of claim 9 in which said first set of probes includes 4 probes and said second set of probes includes 4 probes.

13. The dental x-ray aligning system of claim 9 in which the distance between said first circle and said second circle is from 2 to 10 centimeters.

14. The dental x-ray aligning system of claim 1 in which said current means passes a direct current through said Hall effect probes.

15. The dental x-ray aligning system of claim 14 in which the direct current of said current means pulsates.

16. A dental x-ray aligning system for aiming a dental x-ray apparatus at an x-ray film plate comprising:

a. a magnet;

b. magnet positioning means for maintaining said magnet in a fixed relation with an x-ray film plate;

c. at least three magnetic field sensors;

d. probe positioning means for maintaining said magnetic field sensors in fixed relation to the dental x-ray apparatus;

e. detection means for detecting and measuring magnetic field strengths sensed by said magnetic field sensors; and

f. indicator means for comparing the detected magnetic field strengths and for indicating alignment of the dental x-ray apparatus with the x-ray film plate.