O b j e c t i v e s: To identify tooth diseases as potential causative factors in the development of maxillary sinus lesions, with the aid of clinical examination combined with Cone Beam Computed Tomography (CBCT), in the patients with persistent sinus-like ailments, unresponsive to routine treatment offered by otolaryngologists.

M a t e r i a l s a n d M e t h o d s: In 44 patients with suspected odontogenic maxillary sinusitis, a dental examination with tooth vitality test was carried out, in conjunction with CBCT. The study involved 29 women and 15 men (age range 19–69 years, mean age 43 (SD = 13.9) years).

R e s u l t s: In 15 (34.1%) patients the odontogenic lesions were encountered in maxillary sinuses. A total of 33 causative teeth were identified, of which 13 (39%) were after root canal treatment (RCT). Only one of the teeth had a properly reconstructed crown, and only one tooth had the root canals properly filled-in. Most frequently, the lesions in the sinuses were attributed to the inflammation of periapical tissues; the first molar having been established as the most common causative tooth.

C o n c l u s i o n s: A detailed dental examination, pursued in conjunction with CBCT analysis, allow to diagnose odontogenic maxillary lesions. The incidence of long-term ailments originating in the maxillary sinuses should prompt a detailed assessment of the teeth, especially those after RCT.