Apical Periodontitis and Maxillary Sinus Alterations: Results of an Exploratory Cross-Sectional Tomographic In Vivo Study

Odontogenic sinusitis is a highly prevalent yet frequently overlooked condition. Since anatomically, the roots of the upper molars and premolars may be in proximity to the maxillary sinus, apical periodontitis affecting these teeth may lead to the development of sinus membrane thickening suggestive of odontogenic sinusitis. The present cross-sectional study aimed to investigate the relationship between images suggestive of apical periodontitis and alterations in the maxillary sinus. One hundred and thirty Cone Beam Computed Tomographies (CBCTs) of the posterior maxilla were examined for the presence of apical radiolucent lesions and thickening of the sinus membrane. The relationship between the distance of the lesions from the sinus and the prevalence of sinus alterations was described and compared using a chi-squared test and logistic regression models. In the sample studied, 16.12% and 45.96% of the sinus images suggested mucositis and sinusitis, respectively. The mere presence of radiolucent apical lesions was not related to sinus alterations. However, lesions breaking through the cortical floor of the sinus were associated with a larger mucosal thickness, reaching statistical significance on the left side. Estimation of the magnitude showed that increasing the sample size would lead to a statistical difference on the right side as well. Thus, it can be concluded that, in cases where lesions suggesting apical periodontitis are closely related to the sinus floor, breaking though the cortical bone of the maxillary sinus floor, the prevalence of sinus mucosal thickening, indicating mucositis or sinusitis, is greater.