IMAGE SHIFT OF INTRACORONAL PINS VIEWED ON BITE-WING AND PANORAMIC RADIOGRAPHS

Pins were placed into dentin in molars and premolars in a dried mandib le. Panoramic and bite-wing radiographs were obtained, and measurement s of the images of pins on these radiographs were compared with measur ements of the mandible. The bite-wing radiographs showed little distor tion of the relative distance between pins. The panoramic radiographs showed magnification and parallax shift of images of pins; the distanc e between pins placed mesially and distally in a tooth was magnified m aximally at the first molar, decreasing to the third molar. For pins r elated diagonally in a tooth, the image showed magnification and paral lax shift so that the apparent distance between pins placed mesiobucca lly and distolingually increased from bicuspid to third molar, whereas distobuccally and mesiolingually placed pins showed the reverse trend . Guidelines are given for the evaluation of bite-wing and panoramic r adiographs that can give clinically valuable information about the pos itions of intracoronal features.