Odontogenic Sinusitis: The Selective Role of a Modified Caldwell–Luc Approach in Two CT/CBCT-Documented Cases

Tooth-bearing structures are commonly involved in the spread of various odontogenic lesions. Radicular and dentigerous cysts are among the most common odontogenic cysts, exhibiting significant variations in size and morphology within the jawbones. On the other hand, the influence of dental caries, periodontal diseases, and periapical lesions extends beyond tooth-bearing bone and also affects adjacent anatomical structures, especially the maxillary sinuses. In addition to untreated odontogenic lesions, treatment-related complications in the posterior maxilla may also disturb the sinus environment, particularly when oroantral communication is not recognized or adequately managed. The etiology of sinusitis is multifactorial; however, tooth-related infections are the primary cause of odontogenic sinusitis (ODS). Routine upper posterior tooth extraction may also become clinically significant when pre-existing sinus mucosal changes, close sinus floor proximity, or persistent oroantral communication are overlooked. When ODS is undiagnosed or overlooked on a classic computed tomography or a cone beam computed tomography (CBCT) scan, it is frequently inadequately managed by otolaryngological interventions alone; this leaves the underlying dental pathology unaddressed. Consequently, the utilization of CT/CBCT and close collaboration between dentists, oral surgeons, and otolaryngologists are essential for the successful management of these conditions. In advanced cases of ODS, isolated intranasal otolaryngological procedures are often insufficient. Comprehensive management relies on the elimination of all sources of odontogenic infection through endodontic therapy, dental extractions, and localized bone curettage. While the traditional Caldwell–Luc approach (CLA) is not commonly used nowadays, it remains an important surgical option in select cases, especially when infection spreads beyond tooth-bearing structures or soft tissue abscesses are present. This paper presents the radiological and clinical findings of two ODS cases with different etiologies and demonstrates how these findings influenced surgical planning. The aim is not to introduce the Caldwell–Luc approach as a novel technique but to illustrate its selective role when the direct treatment of the odontogenic source and oroantral defect is required.