Figure 7a. CT images in a 64-year-old patient with endodontal and periodontal disease extending into the maxillary sinus. (a) On transverse view, inflammation has the appearance of polyps or retention cysts (arrow). (b) The panoramic view, however, reveals mounds of inflammation (straight arrows) centered over the root apex of the teeth, which are affected by advanced endodontal and periodontal disease. Note the resorption of bone due to the infection (arrowheads) and the empty socket (curved arrow), where the tooth was lost because of periodontal disease. m = maxillary sinus, n = nasal turbinate. (Reprinted, with permission, from reference 8.)