The incidence, location, and height of maxillary sinus septa in the edentulous and dentate maxilla

Purpose: This study evaluated the incidence, location, and height of antral septa and demonstrates their clinical implications. Materials and methods: One hundred ninety-four maxillary posterior regions, subdivided into four groups (group 1, 61 clinically examined atrophic ridg es; group 2, 41 anatomically examined atrophic ridges; group 3, 42 radiogra phically [CT] examined atrophic ridges; and group 4, 50 CT examined dentate maxillary ridges), were examined for the incidence, location, and height o f antral septa. Results: The incidence of antral septa was significantly greater (P < .01) in atrophic edentulous regions (groups 1, 2, and 3) than in dentate regions (group 4). However, the septa were much lower (P < .01). In atrophic maxil lae, about 70% of antral septa were located in the anterior (premolar) regi on. Conclusions: Antral septa are more commonly found in edentulous atrophic ma xillae than in dentate maxillae. The septae in edentulous atrophic maxillae are shorter than those found in dentate maxillae. When present, maxillary sinus septae are more common anteriorly than posteriorly. CT scanning is th e preferred radiographic method for detecting the presence (or absence) of sinus septae. Panoramic radiography has less sensitivity and specifity than CT scanning for the detection of sinus septa.