Periodic identical intraoral radiographs. A modified Eggen technique.
A method for obtaining periodic identical radiographs with a modified long-cone paralleling technique is described. The appliance consists of a modified Eggen film positioner and an aiming device fastened to a long cone. There was no fixed connection between the film positioner and the x-ray machine. Radiographs have been obtained from twenty-five patients participating in a long-term study of apicoectomy with retrograde root filling. The intervals between the radiographs ranged from 0 to 12 months. A long-term error and a short-term error of the method were found. The method proved to be accurate and fast compared to those described previously.