Image distortion in rotational panoramic radiography. II. Vertical distances

Films, exposed with rotational panoramic radiography, are generally considered inferior regarding the accuracy of measurements. Theoretic mathematical calculations, confirmed by an experimental test, have been performed in order to evaluate the reliability of measurements of distances that appear vertical in the image. It is demonstrated that, within certain limits, the panoramic film may be used for vertical measurements in clinical practice provided the patient has been properly positioned in the equipment during the exposure.