Maxillary Sinus Morphology: A Radiographic Retrospective Evaluation of Sinus Septa in Caucasian and African-American Subjects

Abstract

Anatomic variations of maxillary sinus morphology including volume and septa impact the success of sinus augmentation procedures for dental implant placement. Anatomy has been investigated mainly with respect to age and gender; however, the effect of race has not been examined. The purpose of this study was to evaluate variations of maxillary septa sinus anatomy of African-American and Caucasian subjects, given differences significantly impact treatment success. This retrospective study examined consecutive computerized tomographic scans (CT) of patients scheduled for maxillary implant surgery at the University of Maryland School of Dentistry between 2009 to 2011. A total of 259 CT scans of 139 African-American and 120 Caucasian subjects were evaluated, of which, 62.5% of subjects (162/259) had identifiable septa. A total of 343 septa were identified in 518 sinuses (66.2%). Caucasians had more septa than African-Americans (1.56 compared to 1.09, p=0.006). The effect of gender was approaching significance (p=0.07). The adjusted mean number of sinus septa in female subjects was 1.48 compared to 1.17 in males. Sinuses were divided into three sections: anterior (premolars), middle (first and second molars), and posterior (third molar). In both the anterior and middle sections, race had a significant effect (p=0.033 and p=0.035). In the anterior, the adjusted mean number of septa for Caucasians was nearly twice that of African-Americans (0.32 compared to 0.17). In the middle section, the adjusted mean for African-Americans was 0.57 compared to 0.79. With respect to the posterior section, only gender had a significant effect (p=0.008). Women had an adjusted average of 0.51 septa compared to men with a 0.29 average. The majority of septa were found in the middle segment (51.3%, 176/343), and 17.5% (60/343) were identified in the anterior segment. Sinus septa complicate Schneiderian membrane elevation therefore increasing likelihood of membrane perforation, a common complication of sinus augmentation procedures. The dentally relevant sinus segments contain the majority of sinus septa (68.8%) and have a direct impact on clinicians performing sinus augmentation procedures. Both race and gender impact maxillary implant treatment planning with a greater frequency of detectable septa in Caucasians and females when compared to African-American males.