Odontogenic Factors Associated with Maxillary Sinus Schneiderian Membrane Thickness and their Relationship to Chronic Sinonasal Symptoms: An Ambispective Cohort Study

Odontogenic sinusitis is a common maxillary sinus disease. It develops due to the violation of the Schneiderian membrane due to pathological, iatrogenic, or traumatic causes from dental and dentoalveolar structures. The aim of this cohort study was to investigate local and systemic factors associated with Schneiderian mucosal thickening (MT) in patients referred for evaluation of apical periodontitis (AP) and examine their relationship with chronic sinonasal symptoms. Cone-beam computed tomography (CBCT) scans of 197 patients referred for evaluation of endodontic diseases were reviewed. Mucosal thickening in relation to the affected tooth was measured in the coronal section in millimeters at the maximum area perpendicular to the bone. Based on this measurement, the sinus floor was categorized for MT as present (>1 mm) or absent (