Pathologic conditions of the maxillary sinus

Radiography of the maxillary sinuses is often undertaken using computed tomography, magnetic resonance imaging, or the occipito-mental plain x-ray film projection. However the panoramic radiograph has been found superior to the latter for detection of “cyst-like densities.” [1]. The occipito-mental technique, first described by Waters and Waldron, clearly demonstrates the superior, inferior and lateral margins of the maxillary sinuses while reflecting the shadows of the petrous temporal bones downwards below the inferior margin of the sinuses [2]. It also demonstrates well any soft tissue or fluid contents of the sinus [1]; however, this method does not display the cortices of the anterior and posterior wall. While CT, MRI and the Waters’ projection are well suited to demonstrate the maxillary sinuses, these methods are only employed if there are signs and symptoms of disease, by which time the prognosis for patients having such insidious disease as squamous-cell carcinoma can be poor [3]. Extensive lesions occupying the maxillary sinus can produce surprisingly few clinical features [4]. For this reason, the panoramic radiograph can be the primary indication of maxillary sinus disease. While panoramic radiography can be used to detect maxillary sinus disease, it cannot be used to entirely exclude sinus pathology. Only the portions of the sinus that are within the image layer will be demonstrated. As the panoramic image layer most closely reflects the dental arch, sinus disease occasionally arises within the sinuses outside the image layer. Diseases of the maxillary sinus are comparatively frequent, even in apparently young individuals – with rates in excess of one in five individuals examined using the Waters’ projection (mucosal thickening 12.3%; cysts or polyps 7.2%; opacified sinus 3.3%) [5]. For this reason, it is incumbent upon the dental practitioner to understand the panoramic radiological features of disease and normal variations within the paranasal sinuses. Certainly the patient should not be referred to an ear, nose and throat specialist for every instance of antral mucosal thickening or mucous retention cyst (Fig. 1 &2), nor should the dentist ignore features that possibly reflect an early malignancy. The reputation of a practitioner is greatly enhanced given appropriate referrals that can make the difference between life and death. Failure to diagnose, on the other hand, can result in notoriety. Nortjé et al [3] were among the first to comprehensively study the appearance on panoramic dental radiographs of pathological conditions affecting the maxillary sinuses, comparing inflammatory conditions of dental origin, iatrogenic disease/foreign bodies, non-odontogenic inflammatory conditions, cysts, benign neoplasms, malignant neoplasms and dysplasias affecting the maxilla. Pathologic conditions of the maxillary sinus