MAXILLARY MOLARS LESSON 4

Position the posterior instrument assembly in the patient's mouth, with the plastic bite-block centered on the second molar (see figure 4-21). Be sure that the anterior edge of the film is adjacent to the distal of the second bicuspid. Parallel the film with the long axis of the molars. Place a cotton roll between the underside of the teeth and the block and have the patient close his teeth in order to maintain the film position. Move the locator ring along the indicator rod to approximately the skin surface and align the x-ray unit extension tube with the rod and the ring on horizontal and vertical planes.