Bisecting Angle Technique Alternative to Paralleling Technique

In dental radiography, using the paralleling technique is not always possible. The bisecting angle technique is an alternative, although it is not the most ideal technique. There are 2 modifications of this technique.  Modification 1: For the first modification, the image receptor is placed against the tooth that needs to be imaged. The x-ray beam must be aimed perpendicular to the imaginary bisecting angle between the long axis of the tooth and the long axis through the image receptor. This can be performed with the rectangular collimator, too, to keep the radiation dose as low as possible. However, this technique is prone to geometric exposure errors because there are no extraoral aiming aids. The Rinn® Bisecting Angle Instrument (BAI) holder can be used to help obtain good images with this technique.  Modification 2: For the second modification, the image receptor is placed on the occlusal surface of the teeth. The x-ray beam is aimed perpendicular to the imaginary bisec more...