Table 1.
Descriptive statistics and comparison of facial symmetry parameters between genders (independent samples t-test). OS, original facial shell; MS, mirror facial shell; Max., maximum; exR-exocanthion right; exL-exocanthion left; chR-cheilion right; chL-cheilion left; msp, midsagittal plane; mid (subscripted), the middle of the distance between bilateral landmarks; g, glabella; n, nasion; prn, pronasale; sn, subnasale; ls, labiale superius; li, labiale inferius; pg, pogonion; ps, palpebrale superius; pi, palpebrale inferius; ex, exocanthion; en, endocanthion; al, alare; cph, crista philtri; ch, cheilion; SD, standard deviation; range, minimum to maximum; diff., difference; CI, confidence interval; n.s., not significant.
| Parameters | Males (n = 123) | Females (n = 147) | Mean difference/ratio (95% CI) | P value | ||
| Mean (SD) | Range | Mean (SD) | Range | |||
| Three-dimensional facial symmetry | ||||||
| Whole face (%) | 53.49 (10.73) | 31.01–79.55 | 58.50 (10.27) | 31.99–83.14 | −5.01 (−7.54 to −2.48) | <0.001* |
| Upper third (%) | 53.41 (13.03) | 22.23–83.50 | 59.84 (14.52) | 24.17–91.34 | −6.43 (−9.78 to −3.08) | <0.001* |
| Middle third (%) | 54.07 (13.53) | 18.14–84.43 | 58.87 (12.07) | 30.49–85.10 | −4.80 (−7.88 to −1.72) | 0.002* |
| Lower third (%) | 54.69 (21.92) | 10.34–98.10 | 57.26 (18.25) | 10.26–99.10 | −2.57 (−7.39 to 2.24) | 0.294 (n.s.) |
| Mean OS–MS (mm) | 0.61 (1.28)** | 0.33–1.14 | 0.54 (1.27)** | 0.28–1.05 | 1.14 (1.07 to 1.20) | <0.001* |
| Max. OS–MS (mm) | 2.85 (1.35)** | 1.46–4.98 | 2.67 (1.37)** | 1.34–4.92 | 1.07 (0.99 to 1.14) | 0.084 (n.s.) |
| Angular parameters | ||||||
| 1. exR–exL–pg (°) | 65.32 (1.35) | 62.15–68.73 | 64.59 (1.51) | 61.32–68.98 | 0.73 (0.38 to 1.08) | <0.001* |
| 2. exL–exR–pg (°) | 65.85 (1.44) | 62.26–69.68 | 64.97 (1.49) | 61.41–69.32 | 0.88 (0.53 to 1.23) | <0.001* |
| Difference 1−2 (°) | 1.31 (1.12) | 0.01–5.47 | 1.34 (0.93) | 0.01–5.53 | −0.03 (−0.27 to 0.22) | 0.840 (n.s.) |
| exRexL–chRchL (°) | 2.07 (1.18) | 0.14–6.23 | 2.34 (1.29) | 0.24–7.32 | −0.27 (−0.57 to 0.03) | 0.080 (n.s.) |
| Linear parameters | ||||||
| g–msp (mm) | 0.81 (0.35)*** | 0.01–3.01 | 0.77 (0.33)*** | 0.00–2.27 | 0.04 (−0.04 to 0.13) | 0.286 (n.s.) |
| n–msp (mm) | 0.73 (0.29)*** | 0.04–2.23 | 0.67 (0.30)*** | 0.00–1.74 | 0.06 (−0.02 to 0.13) | 0.135 (n.s.) |
| prn–msp (mm) | 0.78 (0.35)*** | 0.01–4.44 | 0.74 (0.33)*** | 0.00–2.94 | 0.04 (−0.04 to 0.13) | 0.296 (n.s.) |
| sn–msp (mm) | 0.67 (0.32)*** | 0.00–3.42 | 0.62 (0.30)*** | 0.01–2.03 | 0.05 (−0.02 to 0.13) | 0.181 (n.s.) |
| ls–msp (mm) | 0.76 (0.34)*** | 0.00–4.06 | 0.74 (0.33)*** | 0.00–2.70 | 0.02 (−0.06 to 0.10) | 0.557 (n.s.) |
| li–msp (mm) | 0.81 (0.36)*** | 0.00–3.14 | 0.80 (0.36)*** | 0.00–3.25 | 0.01 (−0.07 to 0.10) | 0.816 (n.s.) |
| pg–msp (mm) | 0.94 (0.42)*** | 0.00–6.14 | 0.88 (0.39)*** | 0.00–4.40 | 0.06 (−0.05 to 0.15) | 0.312 (n.s.) |
| psmid–msp (mm) | 0.67 (0.29)*** | 0.00–2.37 | 0.68 (0.31)*** | 0.02–1.95 | −0.01 (−0.08 to 0.06) | 0.827 (n.s.) |
| pimid–msp (mm) | 0.67 (0.30)*** | 0.00–1.98 | 0.71 (0.29)*** | 0.01–1.80 | −0.04 (−0.11 to 0.03) | 0.273 (n.s.) |
| exmid–msp (mm) | 0.68 (0.30)*** | 0.01–1.84 | 0.73 (0.29)*** | 0.00–1.79 | −0.05 (−0.12 to 0.02) | 0.160 (n.s.) |
| enmid–msp (mm) | 0.67 (0.30)*** | 0.00–1.91 | 0.63 (0.30)*** | 0.00–2.83 | 0.04 (−0.03 to 0.11) | 0.274 (n.s.) |
| almid–msp (mm) | 0.52 (0.27)*** | 0.01–3.48 | 0.54 (0.27)*** | 0.00–1.75 | −0.02 (−0.08 to 0.05) | 0.540 (n.s.) |
| cphmid–msp (mm) | 0.83 (0.36)*** | 0.01–4.07 | 0.78 (0.32)*** | 0.00–2.69 | 0.05 (−0.03 to 0.14) | 0.175 (n.s.) |
| chmid–msp (mm) | 0.81 (0.31)*** | 0.00–2.80 | 0.77 (0.34)*** | 0.01–3.19 | 0.04 (−0.03 to 0.13) | 0.227 (n.s.) |
Statistically significant.
Geometric mean and geometric standard deviation.
Square root transformed.