Background and Aim: The aim was to assess the position of maxillary premolars relative to the maxillary sinus floor and alveolar bone in an Iranian population using cone-beam computed tomography (CBCT).
Materials and Methods: This descriptive study evaluated 150 maxillary first and second premolars. The alveolar bone width at the bone crest and the angle between the longitudinal axis of the teeth and the longitudinal axis of the alveolar bone were meas-ured. The relationship between the maxillary premolars and the maxillary sinus floor was categorized into five types. The effect of age, sex and side of the jaw was also statistically analyzed. Data were analyzed using t-test, Fisher’s exact test, and Pearson’s correlation coefficient with 95% confidence interval.
Results: The mean alveolar bone thickness was 9.8 ± 1.3 mm at the site of premolars, and the mean internal angle was 1.19 ± 6.3 degrees. The most common type of root connection with the sinus floor was type 2 in both first and second premo-lars (39.1% and 53.4%, respectively), but no significant difference was observed in the frequency of different types (P>0.05). There was no significant relationship between different types and alveolar bone thickness, but the mean size of internal angle was larger in type 1 (P=0.04). No significant association was detected between types and gender, age or side of the jaw (P>0.05).
Conclusion: The results of the present study may be useful for dental procedures at the site of premolars in absence of 3D imaging.