Dental radiation dose. Sensitometric method for determination of exposure-development factors

Journal Article · Sat Jun 01 04:00:00 EDT 1963 · Oral Surgery, Oral Medicine, Oral Pathology

DOI:https://doi.org/10.1016/0030-4220(63)90072-0· OSTI ID:4631764

Wainwright, W. W.

It is suggested that film speed is the most important single factor in reducing dental radiation exposure but has been given little attention. A necessary step in this direction is the application of quantitative film rating systems (of the type used in general radiography) to dental radiography and attention to exposure development factors. To this end, a sensitometric method is presented for measurement of undesired dental radiation overexposure resulting from underdevelopment. The method is based on a universal curve of density-log relative exposure for dental x-ray film. The curve is applicable to any given film and machine setting in intraoral roentgenography. Correct exposure time can be predicted from the curve after exposure of only two dental films and use of a lead-aluminum penetrometer. This dental penetrometer and the universal sensitometric curve make it possible to conduct mass surveys of the amount of radiation overexposure from exposure-development factors in dental offices. An example of a typical determination of the effect of exposuredevelopment factors on radiation dose is given. The densities were measured with a densitometer in the range from 0 to 8. With an exposure of 1/2 sec and development for 1 1/2 min at 64 deg F, the hypothetical dentist obtained a density of 1.95 under aluminum. Full development gave a much greater density, 4.05, which was found by reference to the universal curve to represent a radiation exposure of 3.5 times normal. In other words, the underdevelopment (1 1/2 min at 64 deg F) was compensated by overexposure (1/2 sec), so that films of normal density could be obtained. The dentist was informed of the overexposure, and it was predicted that by dividing his time (1/2 sec) by the radiation exposure (3.5), with full development, he would be able to reduce exposure time from 0.5 to 0.143 sec. On the corrected film with an exposure time of 0.15 sec, the density is 1.72. By changing to full development, the dentist obtained normal density with 1/3 the amount of radiation.

• Research Organization: George M. Hollenback Research Associates, Encino, Calif.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-039335
• OSTI ID: 4631764
• Journal Information: Oral Surgery, Oral Medicine, Oral Pathology, Journal Name: Oral Surgery, Oral Medicine, Oral Pathology Journal Issue: 6 Vol. 16; ISSN 0030-4220
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
ABSORPTION
ALUMINUM
BONES
DENSITOMETERS
DENSITY
DIAGRAMS
EFFICIENCY
LEAD
MATHEMATICS
MEASURED VALUES
NUCLEAR EMULSIONS
PERFORMANCE
PHOTOCHEMISTRY
PHOTOGRAPHIC FILM
PHOTOMETRY
RADIATION DOSES
RADIOGRAPHY
SENSITIVITY
TEETH
X RADIATION