The integral absorbed dose in conventional and panoramic complete-mouth examinations

Abstract

Conventional and panoramic complete-mouth x-ray examinations differ in so many respects that a comparison of the amount of radiation administered to the patient cannot be made with the use of exposure measurements in roentgens. The integral absorbed dose, being the total amount of energy absorbed by the patient and expressed in gram rads or ergs, is more suitable for this purpose. This dose was determined by measuring the amount of energy passing through a cross section of the x-ray beam before entering the patient.

The integral absorbed dose for a complete-mouth examination with the conventional technique was, for two different techniques, 700 and 1,300 gram rads. It can be shown that, for the conventional technique, an increase in KVP reduces the amount of radiation which the patient receives, but not as dramatically as the skin exposure suggests. Examination by the panoramic technique with the Orthopantomograph delivers 110 gram rads to the patient, whereas 19 gram rads is administered during examination with the Panoramix. These findings constitute an argument in favor of the new techniques and emphasize the need to consider them when selecting a technique for a complete-mouth examination.