Anatomical descriptions of the maxillary sinus are critical in pathological diagnosis and the treatment planning of surgical procedures. This study was undertaken to develop a new technique for simulating anatomical structures and to clarify the morphological and clinical characteristics of the maxillary sinus. Thirty-three hemi-sectioned Korean heads were used in this study. CT scans and DentaScan reformatted cross-sectional images were taken on all specimens. From the CT images, three-dimensional reconstructed images were made using the V-works program. From the three-dimensional reconstructed images of the maxillary sinus, six categories of maxillary sinus were created, categorized according to their lateral aspects and shapes of the inferior walls. In 55%, a flat inferior wall of the maxillary sinus was observed. All measurements (anterior-posterior length, height, width and volume) of the sinus were larger in males than in females. From the DentaScan reformatted panoramic images, the anterior limit of the maxillary sinus was located in the first premolar area (58%), and the posterior limit was in the third molar and maxillary tuberosity area (94%). We therefore offer a new virtual technique for manipulating three-dimensional reconstructed images easily on a personal computer. On the reconstructed images the three-dimensional morphology could be observed and the anatomical characteristics of the maxillary sinus and surrounding structures could be determined.