[The measurement of pneumatization of maxillary sinus extended into alveolar process basing on the CT and its clinical significance].

To investigate the significance of pneumatization of maxillary sinus extended into alveolar process.One hundred outpatients encountered were included in this study. The pneumatizations of maxillary sinus extended into alveolar process were observed and classified. Depth of surgical procedure of maxillary sinus in different type was measured.The actual depth of surgical procedure of maxillary sinus of in different types of the alveolar process pneumatization varied greatly. The actual depth of surgical procedure of maxillary sinus in type Ⅲ pneumatization of alveolar process were (32.27±3.48)mm, which were significantly deeper than type Ⅱ (28.35±3.45)mm and type Ⅰ(20.73±3.09)mm (< 0.05 respectively). Moreover, the actual depth of surgical procedure of maxillary sinus in type Ⅱ was also deeper than type Ⅰ(< 0.05).The pneumatization of maxillary sinus extended into alveolar process can significantly affect the actual depth of the maxillary sinus in the operation of endoscopic middle meatus antrostomy, which may serve as a reference for the choice of endoscopic maxillary sinus approaches.