Abstract: Objective: To describe the radiographic features of odontogenic maxillary sinusitis using cone beam computed tomography (CBCT) scans and to determine whether any tooth was more frequently associated with this disease. Methods: 500 CBCT scans were classified as normal sinus, maxillary sinusitis of an odontogenic origin, maxillary sinusitis of a non-odontogenic origin and maxillary sinusitis of an undetermined origin. Result: Sinusitis of odontogenic origin was recognized if it met the following criteria: carious tooth, tooth with defective restoration, or extraction site with or without radiographically periapical lesion and mucosal thickening limited to the area of the tooth or extraction site in question. 124 maxillary sinusitis with possible odongenic origin were detected, which accounted for 48.6% of all the maxillary sinusitis. Maxillary first molar was most likely to be frequently associated with odontogenic sinusitis. In sinuses in which the thickening was more than 2mm, the mean mucosal thickening was 6.11±4.43mm Conclusion: Among patients with maxillary sinusitis, nearly half of the cases appear to be associated with odontogenic pathology. Maxillary first molar is the most likely to cause odontogenic maxillary sinusitis. The use of CBCT scans can provide the accurate anatomic structure of maxillary sinus and the changes in it.

Key words: cone beam computed tomography, odontogenic maxillary sinusitis, periapical disease