Recognizing Odontogenic Maxillary Sinusitis in the ENT Clinic: Four CT Findings That Should Prompt Dental Evaluation

Objective: This retrospective cohort study evaluated the proportion of maxillary sinuses with radiographic findings consistent with an odontogenic contribution among patients with imaging-confirmed acute or chronic maxillary sinusitis presenting to a single academic ENT clinic over one year. Sixty-five CT scans (84 sinuses) underwent multidisciplinary review for prespecified radiographic features. By highlighting imaging findings indicative of dental origin this study aims to improve recognition of possible odontogenic disease and appropriate multidisciplinary evaluation. Methods: Sixty-five patients were evaluated. Inclusion criteria required a visit diagnosis of chronic maxillary sinusitis (ICD10 J32.0) or acute maxillary sinusitis (ICD10 J01.00, J01.01), and a sinus CT within the preceding year. Each scan underwent multidisciplinary review by an oral and maxillofacial radiologist, an otolaryngologist, an otolaryngology resident, and a medical student. Scans were evaluated for maxillary sinus floor mucosal thickening and radiographic features suggestive of an odontogenic contribution, including periapical pathology, oroantral communication, large dental restorations, and widened periodontal ligament (PDL) space. Dental referral recommendations were based on multidisciplinary consensus from CT findings alone. Data were summarized using descriptive statistics. Results: Radiographic findings consistent with an odontogenic contribution were identified in 50/84 (59.52%) affected maxillary sinuses from 40 patients. Among these 50 sinuses, 17 (34%) showed widened PDL space, 15 (30%) showed oroantral communication, 28 (56%) showed periapical pathology, and 9 (18%) showed large dental restorations. There was consensus among the multidisciplinary team that in retrospect, among the 40 patients with OS, 38 required dental referrals. Conclusion: Radiographic findings consistent with an odontogenic contribution indicated a higher single-center cohort prevalence than expected based on population-level prevalence reports. The findings support deliberate review of the maxillary dentition on sinus CT, with this study outlining the key imaging features for odontogenic sinusitis.