Comparative Facial Anthropometry of Ijaw and Isoko Adults Using Photographic Measurements

Abstract

Background: While symmetry and proportionality are recurring perceptual markers of facial attractiveness, aesthetic evaluation is also influenced by cultural norms, social context, and temporal variation. This study therefore examined the proportional and symmetrical relationships of facial features among the Ijaw and Isoko people using photogrammetric analysis. Material and Methods: This comparative study included 400 participants (200 Ijaw and 200 Isoko), aged 15–35 years. Facial measurements were obtained from anterior and lateral photographs of students from both ethnic groups. The photographs were printed on A4 paper and measured at life size using a meter rule. Facial measurements and proportional relationships were assessed using Cunningham’s anthropometric landmarks and reference proportions. Results: Most facial parameters showed no significant ethnic differences among males (p > 0.05). However, width of face at eye level (16.26 ± 0.99 vs 15.09 ± 1.44; p < 0.001), chin length (3.58 ± 0.42 vs 3.88 ± 0.42; p < 0.001), width of face at mouth level (14.18 ± 1.21 vs 13.47 ± 1.30; p < 0.001), LNEB (7.79 ± 0.55 vs 7.49 ± 0.80; p = 0.005), and upper and lower lip positions relative to the esthetic plane (p < 0.01) differed significantly between Ijaw and Isoko males. In contrast, females exhibited more pronounced inter-ethnic variation, with significant differences in width of face at eye level (16.18 ± 1.08 vs 15.30 ± 1.27; p < 0.001), chin length (3.66 ± 0.35 vs 3.85 ± 0.43; p < 0.001), eye width (3.10 ± 0.38 vs 3.32 ± 0.40; p < 0.001), mouth width (6.36 ± 0.69 vs 6.85 ± 0.78; p < 0.001), several facial linear measurements (VLNEB, LNEB, rVLEM, and lVLEM; p < 0.001), nasolabial angle (85.27 ± 8.36 vs 80.17 ± 9.77; p < 0.001), and lip positions (p ≤ 0.005), whereas parameters such as total facial height remained comparable (p > 0.05). Comparison with Cunningham’s proportions revealed notable deviations in WFEL–WE (approximately 21–23% vs the ideal 30%) and NL–EL ratios (approximately 119–123%), whereas most other proportions closely approximated the classical standards, indicating measurable ethnic- and sex-based variations in facial morphology. Conclusion: This study provides baseline comparative anthropometric data for Ijaw and Isoko participants. Several facial proportions in this sample approximated the selected reference ratios; however, these findings should be interpreted as population-specific morphometric observations rather than evidence of a universal standard of beauty.