CBCT images obtained from 394 patients. Data including the age, gender, the angulation type, depth of the third molars, and horizontal and vertical positions of the maxillary sinus relative to the third molars were examined. Results: Among 394 patients, 215 (54.6%) were male and 179 (45.4%) were female. The most common angulation of impaction was vertical (80.2%). Based on the depth of the third molars in relation to the adjacent second molar, Class A was the most common. Regarding the relationships of the third molars with the maxillary sinus, vertical Type I (43.5%) and horizontal Type II (59.3%) were seen most frequently. There was a significant difference between the vertical and horizontal relationships (P < 0.05). Conclusions: Knowledge of the anatomical relationship between the maxillary sinus floor and maxillary third molar roots is important for removing a maxillary third molar. CBCT evaluation could be valuable when performing dental procedures involving the maxillary third molars....