[The radicular cyst in the maxillary sinus encountered in the clinical otorhinolaryngological practice].

This article was designed to report the clinical case of the radicular cyst localized in the maxillary sinus of the 23 year-old man that had been detected before the surgical intervention was undertaken for its treatment. In the preceding visits of the patient to other medical settings, this condition was misinterpreted as a genuine (rhinogenic) cyst. It accounted for the choice of the inadequate surgical strategy for the management of this pathology. As a result, the patient experienced two relapse episodes of the disease. The thorough analysis of the patient's medical history and CT images of the sinus obtained during the 4 year follow up period allowed to establish the definitive diagnosis of odontogenic cyst of the upper jaw. The authors present a brief overview of the relevant scientific literature concerning etiology and pathogenesis as well as the methods of diagnostics and treatment of radicular cyst of the upper jaw.