On the diagnosis and pathogenesis of intramural maxillary cysts

In order to study the etiology of the intramural maxillary cyst, which is the origin of the choanal polyp, an antrotomy was performed on 27 patients with such cysts. The cyst-fluid was analysed with respect to protein distribution and bacterial growth. The findings indicate an inflammatory process characterized by high concentrations of immunoglobulins and by consumption of complement and antiproteases. The growth of bacteria, primarily an oral flora found in the cyst-fluids studied, and the sites of cyst attachment, may indicate an epithelial residue of the dental list as the origin of the intramural cyst. It is further suggested that bacterial substances will provoke an inflammatory response, giving rise to an expansion of the cyst. In all cases studied, the cyst-fluid was capable of gelling after a couple of minutes at room temperature. This observation seems to be a reliable diagnostic procedure at antral aspiration, distinguishing the cyst-fluid from the serous transudate of the serous sinusitis, which according to our results, does not have this capacity to form a gel.