A study on radiation dose in dental radiography measured on human body and phantom.

Abstract

Dental radiography is a very important diagnostic tool in modern dentistry. It also provides additional information for setting the procedure for the patient's future treatment. Dental radiography belongs to the low radiation dose class. The magnitude of the risk remains uncertain. This study provides for an informed selection in terms of the risk of these procedures. The thermoluminescent dosimeter (TLD) and a Rando phantom were used to detect the radiation dose on various organs including the optic lens, thyroid gland, gonad and spinal cord. The TLD was also placed on the skin surface of the volunteers corresponding to that of the phantom. The dose to the organs in their real position was calculated mathematically. We found that the dose on the lens was greatly affected by both the direction of the main beam of radiation and the distance between the exposed site and the organ. But the dose on the thyroid gland was mainly related to the direction of the ray and the exposure time. Gonadal dose may be related to the angulation of the central beam and the distance between the central beam and gonadal organ. In addition, the time factor may also be related. For the spinal dose, it may be mainly attributed to the target-organ distance and the angulation of the beam. In view of the angulation of the central ray and distance between the exposed site and the organ, the results showed that all the radiation doses were lower than those of previous reports. Possible reasons for these results including the improvement of collimator, beam filtration, increased kilo-voltage, sensitivity of the film, increased focal-film distance and other related factors have been discussed.