Microbiological PCR Characteristics of Odontogenic Sinusitis and Their Clinical Correlates: A Cross-Sectional...

Background: Odontogenic sinusitis (ODS) represents a distinct form of maxillary sinus inflammation arising from dental pathology and is most commonly unilateral. Despite its polymicrobial nature and predominance of anaerobic organisms, molecular characterization of the bacterial profile and its relationship to clinical severity remains limited. This study aimed to evaluate associations between targeted quantitative PCR (qPCR) findings from paired maxillary sinus and periapical lesion samples and clinical, endoscopic, and radiological features of disease. Additionally, the influence of oroantral communication on microbial concordance between odontogenic and sinus sites was examined. Methods: Twenty-eight patients with confirmed ODS were included for analytical cross-sectional study and underwent combined otolaryngological and dental assessment. During endoscopic sinus surgery with extraction of the causative tooth, paired specimens were collected from sinus mucosa and periapical lesions under sterile conditions and preserved for molecular analysis. Targeted qPCR assays using 16S rRNA-based primers were performed to detect predefined odontogenic pathogens. Associations between bacterial detection patterns and clinical, endoscopic, and imaging variables were analyzed. Results: Detection of Streptococcus anginosus group organisms was significantly associated with complete maxillary sinus opacification. Fusobacterium nucleatum and Porphyromonas endodontalis demonstrated higher detection rates in patients with more advanced radiological disease, although statistical significance was not reached. Purulent nasal discharge correlated with detection of Fusobacterium nucleatum, Porphyromonas endodontalis, and streptococcal species. Cases with intraoperative oroantral communication exhibited greater concordance between sinus and dental microbial profiles. Conclusions: ODS is characterized by a polymicrobial environment dominated by anaerobic bacteria, with specific organisms associated with markers of disease severity such as purulent secretion and extensive sinus opacification. Targeted molecular profiling may improve recognition of odontogenic origin and support individualized therapeutic strategies, although larger studies integrating clinical outcomes are required to clarify prognostic implications.