Objectives: There is increasing research regarding pathology of the maxillary sinus in dentistry. This may be attributed to the increasing routine use of cone beam computerized tomography (CBCT) for diagnosis and treatment planning of complex dental treatments, and incidental findings identified by clinicians during the process. This study aims to compare two different CBCT viewing software programs, and evaluate their detection of pathological findings in the maxillary sinus of a group of patients at Temple University School of Dentistry. Methods: A total of 316 CBCT scans taken on 176 females and 140 males (202 Caucasian, 69 African-American, 30 Asian, and 15 Hispanic) between 2009 and mid- 2013 by the Division of Oral & Maxillofacial Radiology at Temple University School of Dentistry were evaluated using i-CAT and INFINITT viewing software programs. The CBCT scans were examined with both viewing programs, and classified each time by independent evaluators as yielding one of 5 categories of maxillary sinus pathology as follows: healthy status with mucosal thickening ≤ 3 millimeters, mucosal thickening > 3 millimeters, polypoidal mucosal thickening, partial opacification, or complete opacification. Results: The i-CAT viewing program revealed 193 (61.1%) scans with a healthy maxillary sinus presenting with mucosal thickening ≤ 3 millimeters, and 123 (38.9%) scans yielding various forms of maxillary sinus pathology. In comparison, the INFINITT viewing program found 194 (61.4%) scans with healthy maxillary sinus conditions without pathology, and 122 (38.6%) scans with various types of maxillary sinus pathology. The difference in detection of maxillary sinus pathology between the i-CAT and INFINITT viewing programs was not statistically significant. Conclusions: The i-CAT and INFINITT viewing software programs for evaluation of human CBCT scans used in dental treatment planning provided nearly identical information relative to detection of maxillary sinus pathology. This suggests that both viewing programs may be employed interchangeably by clinicians in their pre- treatment evaluation of the maxillary sinus in dental patients. / Oral Biology