Abstract: PURPOSE: To study the height of alveolar ridge and the distance between the wall of maxillary sinus on the curve of the dental arch, and to explore the guiding significance for maxillary sinus surgery and edentulous jaw implant surgery. Methods: Cone-beam CT(CBCT) data of 105 objects were selected to measure the height of alveolar ridge and the maximum bone internal distance between the wall of maxillary sinus 10 mm and 12 mm above the alveolar crest horizontally on the curve of the dental arch. Forty-nine objects with alveolar ridge height on the molar area less than or equal to 10 mm were included for further investigation. The distance between the maxillary sinus wall, and the angle between the maxillary sinus wall on the horizontal plane were measured and calculated. SPSS 22.0 software package was used for statistical analysis of the data. Results: The mean value of the alveolar ridge height in the posterior teeth area was first premolar > second premolars > second molars > first molars. The mean value of the horizontal distance between the wall of sinus 10 mm and 12 mm above the alveolar crest horizontally was (82.40±27.56) mm and (70.54±29.70) mm in 105 objects, while (67.85±28.53) mm and (52.75±24.90) mm in 49 included objects, respectively. The mean value of the angle between the maxillary sinus wall on the horizontal plane was (23.55±39.13)°. There was no significant difference between males and females. However, the horizontal distance had statistically significant differences between different groups and in different horizontal levels of the same group. Conclusions: CBCT is helpful to establish implant surgical plan, and carry out maxillary sinus lift and edentulous jaw implant surgery.

Key words: Maxillary measurement, Cone-beam CT, Maxillary sinus lift, Incline implant