Significance of the position of the sagittal plane of the head for the informative capacity of orthopantomography

In order to extend the study's scope and to improve the segments' investigation, a test of the possibilities of orthopantomography is made at different positions of the sagittal plane. Thirty five skulls were examined with symmetric position of the skull and 5o, 10o and 45o inclines of the sagittal plane against the median plane of the craniostate. Is is shown that the ascending branch of the low jaw with its outgrowts, the last molars and the tuberas of the cheek bones have best visibility at median plane of the craniostate of the sagittal plane. Turning to the contralatteral side improves teeth visibility and that of the respective contours of the lower jaw, upper jaw and maxillary sinuses. The turning angle is 10o for the medial molars and premolars, and 45 o for the canine teeth and incisors. High-quality images of the premolars and canine teeth may also be obtained by turning from 25o to 30o. The maxillary sinuses are visualized well at all turning angles. The analysis of the images, anatomical and projection correlations shows that the better visibility is due to their better disposition in the tomographic zone. The visibility of the medial segments is improved also thanks to favourable changing projection's correlations towards the neck. X-ray films with smaller dimensions have been used. It is also possible to reduce the radiation load to one third/one half compared to the case when the whole jaw is embraced. 7 refs