Mom--I, too, had some problems with my scans being affected by my dental work. You asked about a PET scan......Positive Emission Tomograph....shows very precise details of tissues....it is usually combined with a CT scan, which shows precise location but indistinct detail. The combination gives very good diagnostic information about the nature of a lesion, as well as its location.

The PET uses a radioactive glucose solution that is injected. The marked glucose is taken up by tissues that are more metabolically active than others. Cancer cells are rapidly multiplying cells, so they take up the solution more than normal cells. For this reason.....to get the very most accurate images, you need to curtail your physical activities prior to the scan. My son is a radiologist, and he gave me this advice. He said that, since the most important area of the scan for us is the head and neck...the mouth....one should not eat or chew gum for hours before the scan, nor talk excessively, so that those muscles are not exercised before the scan. You don't want muscle tissue to take up the solution and perhaps disguise the tumor.