Anatomic variations of the osteomeatal complex and its relationship to patency of the maxillary ostium: A retrospective evaluation of cone-beam computed tomography and its implications for sinus augmentation

Aim: The aim of this study is to determine the incidence of obliterated osteomeatal complex (OMC) due to the presence of anatomic variants. Settings and Design: Retrospective Study. Materials and Methods: In this retrospective study, a total of 71 patients, 34 males and 37 females, aged 35-65 years were included in the study. Cone beam computed tomography (CBCT) scans of patients were assessed to identify the status of the OMC in the presence of anatomic variants and their incidence was recorded. The radiological assessment of the anatomical variants was made by viewing the coronal sections of the scans. The variants observed were deviated nasal septum, uncinate process), agger nasi, Haller cells, middle turbinate variants, enlarged bulla, accessory ostium, and maxillary sinus abnormalities). Ostium patency was evaluated in the coronal section of each sinus and classified as "patent" or "obstructed." The most common variants observed were then correlated with the patency of the ostium. Statistical Analysis Used: Chi square test was performed to assess the association between the anatomic variants and the patency of the OMC. Results: In the present study, the incidence of an obliterated OMC due to the presence of anatomic variants was 73.2%. The four most common variants associated with the possibility of an obliterated OMC were the deviated nasal septum (76.2%), middle turbinate (86.4%), enlarged bulla (77.8%), and sinus cavity variants (80.0%). A statistically significant association was noted between middle turbinate variants and Haller cells and the patency of the OMC. Conclusion: Thorough pretreatment CBCT evaluation should be performed to assess the presence of anatomic variants and thereby, the patency of the ostium before sinus floor elevation procedures. The pre and postsurgical treatment plans and regimes can be modified according to anticipated postsurgical sequelae, thereby avoiding postsurgical complications and enhancing the success of the graft procedure.