Assessment of Maxillary Sinus Floor Topography and Root Position of Maxillary Third Molars using Cone Beam Computed Tomography

Introduction: Maxillary sinuses have variable sizes. Knowledge of anatomic correlation between maxillary molars and sinus floor is essential for preoperative assessment in maxillary essment of posterior teeth.

Aim: To assess maxillary sinus floor topography and root position of maxillary impacted third molar position using Cone Beam Computed Tomography (CBCT) imaging.

Materials and Methods: This retrospective study was conducted on the 1080 CBCT images of the upper jaw of patients admitted to Oral and Dental Diseases Research Centre, Kerman University of Medical Sciences, Kerman, Iran, from March 2015 to December 2018. Among these, CBCT images that had atleast one maxillary impacted third molar were evaluated for the position, number and shape of roots and distance from the sinus floor. Data were analysed by Statistical Package for Social Sciences (SPSS) version 26.0, using the Pearson’s Chi-square test.

Results: In the present study, of 1080 CBCT, 100 (9.26%) showed atleast one maxillary impacted third molar. Out of 100 patients, 62% were women and the mean age of samples was 35.73±10.27 years. The roots of 17 impacted molars (13.1%), protruded into the sinus cavity, and 18 (13.84%) of teeth had four roots. Distance from the sinus floor in the left and right-sides were 2.38±0.15 and 2.33±0.17 mm, respectively. Root distance from the alveolar crest in the left and right-sides were 3.40±0.22 and 3.51±0.27 mm, respectively.

Conclusion: The results of the present study showed that roots of 51% of impacted third maxillary molars had a relation with the sinus floor. The most frequent tooth position was mesioangular.