Morphometric analysis of sphenoid sinus using cone-beam computed tomography: potential applications for age and sex estimation in an Egyptian population

Abstract Background The sphenoid sinus exhibits significant anatomical variation with age, sex, and population affinity, which introduces it as a potential candidate for forensic identification in the absence of traditional skeletal markers. Therefore, the objective of this study was to investigate the linear measurements of the sphenoid sinus using cone-beam computed tomography (CBCT) in an Egyptian population to determine its suitability as an indicator for age and sex estimation. Methods This cross-sectional study was conducted on CBCT scans of 290 Egyptian individuals (145 males and 145 females), aged 18 years and above. Sphenoid sinus dimensions, including anteroposterior, inferior-superior, and latero-lateral diameters, were measured using RadiANT software in standardized CBCT planes. Moreover, descriptive statistics were calculated, and measurements were compared between sexes and analyzed across the predefined age groups. Correlations with age were also assessed utilizing Spearman’s rank correlation. Age prediction models were developed using multiple linear regression, and sex classification was performed using logistic regression. Results Males exhibited greater mean values for the inferior–superior and latero–lateral diameters (25.84 ± 3.76 mm and 37.43 ± 6.37 mm, respectively), whereas females showed a slightly longer anteroposterior distance (31.09 ± 5.44 mm). Significant sex-related differences were observed in all sphenoid sinus measurements across most age groups. The measured dimensions correlated significantly with age in the entire sample, as well as when examined separately by sex ( p < 0.001). However, predictive modeling revealed limited discriminatory performance. Logistic regression for sex prediction yielded an area under the ROC curve of 0.62, indicating moderate classification ability. Similarly, the age prediction model explained 32% of the variance in age (R² = 0.32) and had a root mean squared error of 11.62 years, reflecting relatively low predictive accuracy. Conclusions The sphenoid sinus demonstrates measurable sexual dimorphism and age-related variation. However, its predictive performance for sex classification and age estimation is modest, indicating that sphenoid sinus measurements are not sufficiently reliable as standalone forensic indicators. Nevertheless, they may provide supplementary value in the biological profiling of Egyptians when used in combination with other forensic markers.