Comparative evaluation of the distance between the apices of posterior maxillary teeth and the maxillary sinus floor in cross-sectional and panoramic views in CBCT

Proximity of the apices of posterior teeth to maxillary sinus is a concern in any treatment procedure in this area. The aim of present study was to compare the distance of the apices of posterior maxillary teeth to the maxillary sinus floor in cross-sectional and panoramic views in cone-beam computed tomography (CBCT). In this descriptive‒analytical study, 20 CBCT scan samples were selected randomly. The reconstructed cross-sections were evaluated serially, beginning from the anterior segment. The distances from the root apices to the inferior border of the sinus were measured. This distance was also measured on panoramic views. Data were analyzed by SPSS 11.5 using t-test and pair t-test (α = 0.05). The mean distances between the apices of upper first premolars and the maxillary sinus floor on cross-sectional and panoramic views were 9.13 ± 4.17 and 9.51 ± 4.22 mm, respectively (p value = 0.001). These means for upper second premolars on cross-sectional and panoramic views were 7.06 ± 3.40 and 7.51 ± 3.40 mm, respectively (p value = 0.011). These means for upper first molars in cross-sectional and panoramic views were 4.73 ± 2.26 and 4.91 ± 2.25 mm, respectively (p value = 0.011). Finally, for upper second molars, the mean distances were 4.01 ± 1.92 and 4.30 ± 1.95 mm in cross-sectional and panoramic views, respectively (p value = 0.011). Under the limitations of the present study, the distances from the upper tooth apices to the maxillary sinus floor were different on two cross-sectional and panoramic views of CBCT technique and the distance on panoramic view was significantly greater than that on cross-sectional view.