Correct Panoramic Positioning is Key
- Vicki Romans
- May 22, 2012
Two pans were taken on the same patient. One of them was incorrectly positioned. Do you know which one? And, if so, how and why? What was done differently to correct it?
The top image, A, is incorrect. In image A, the incorrect positioning of the patient’s head causes the lower left canine not to visualize. It is not erupted and cannot be seen in the lower anterior mandibular area. But, notice on the lower image (B) it is clearly visible. What positioning adjustment was made and how was it determined?
Note on image A, the anterior teeth are not in focus and very thin and pencil-like in appearance. This indicates that the anterior teeth are out the focal trough (area of sharpness) of the pan unit. The patient’s head position is too far forward, causing the anterior teeth to be in front of the focal trough. Had the anterior teeth appeared magnified, large and fat in appearance, it would indicate that the teeth were behind the focal trough.
The adjustment of moving the jaw backward into the focal trough was made in Image B. The chin was also tucked down or lowered toward the chest to help tuck the chin back into place. By doing so, the gentle “smile” of the teeth was also produced instead of the “sad” expression. This also is important to eliminate the hard palate from becoming superimposed over the apices of the upper mandibular teeth as seen in Image A.
Ideally the “smile” of the dental arch should have been slightly more exaggerated in Image B, but due to the patient’s kyphosis of the upper back, it was difficult to straighten her neck and bring chin down closes to her chest.
If a repeat film had not been taken for poor positioning, the misplaced canine would have been missed entirely. Understanding your panoramic unit and how to correctly use it is critically important for accurate diagnosis.