The relationship between the roots of posterior maxillary teeth and adjacent maxillary sinus floor was associated with maxillary sinus dimension

Background: The dimension of maxillary sinus is dynamic and might complicate the dental practice. Therefore, the purpose of this study is to analyze maxillary sinus dimension with respect to different ages, genders, tooth sites, and relationships between root of posterior maxillary teeth (RPMT) and adjacent maxillary sinus floor, using cross-sectional images from cone-beam computed tomography (CBCT). Methods: The 320 qualified cross-sectional posterior maxillary images of CBCT from 50 patients retrieved from the database were used to analyze the maxillary sinus area. Five types of relationship between RPMT and adjacent maxillary sinus floor were classified accordingly. The associated factors, such as age, genders, and tooth sites, were also examined. The one-way analysis of variance with Tukey's post hoc test was performed to compare the maxillary sinus cross-sectional area in different classifications of RPMT relative to adjacent maxillary sinus floor. Results: There were significant differences of mean maxillary sinus area between different genders (P < 0.001) and age groups (P = 0.01). The mean sinus area measured from cross-sectional images was greater in Type 3 classification of RPMT relative to maxillary sinus, compared to Type 2, Type 1, and Type 0 (P < 0.001). Conclusions: The RPMT relative to adjacent sinus floor may be associated with area of maxillary sinus. The maxillary sinus with greater area in cross-sectional images of CBCT would be closer to the RPMT and might complicate the dental practice.