# Chin Morphology in Relation to the Skeletal Pattern, Age, Gender, and Ethnicity
## 3 Results  
Differences in chin width, height, depth, and volume in terms of anteroposterior and vertical skeletal pattern, ethnicity, and gender are shown in Table 2.  
In terms of the anteroposterior skeletal pattern, differences were observed in chin volume and chin depth. Class III showed significantly larger chin volumes than those of Class I and Class II (Class I: 3071.95 \(\pm\) 1142.58 and Class II: 2994.61 \(\pm\) 908.68, both \(p\) < 0.01 compared to the Class III: 4161.80 \(\pm\) 1335.24). Significant differences in chin depth were seen among all groups, with the largest values seen in Class III, followed by Class I and Class II (Class I: 2.88 \(\pm\) 1.26, Class II: 2.32 \(\pm\) 1.09, and Class III: 4.57 \(\pm\) 2.00, each other \(p\) < 0.01). Ordinal logistic regression analysis (Table 3) indicated that the anteroposterior skeletal pattern was positively associated with chin depth (B = 0.52, \(p\) = 0.00). \begin{table}
\begin{tabular}{l l l l l l} \hline  & & **Volume (mm3)** & **Width (mm)** & **Hight (mm)** & **Depth (mm)** \\ \hline Ethnicity & Korean & 3668.19 \(\pm\) 1297.25 * & 31.94 \(\pm\) 5.27 & 19.68 \(\pm\) 2.23 & 2.95 \(\pm\) 1.58 \\ \cline{2-6}  & Egyptian & 2838.46 \(\pm\) 856.26 & 32.39 \(\pm\) 4.85 & 19.27 \(\pm\) 2.54 & 2.61 \(\pm\) 1.18 \\ \hline Gender & Male & 3648.51 \(\pm\) 1106.16 * & 34.36 \(\pm\) 4.61 * & 20.42 \(\pm\) 2.71 * & 2.99 \(\pm\) 1.45 * \\ \cline{2-6}  & Female & 2655.20 \(\pm\) 827.98 & 30.61 \(\pm\) 4.63 & 18.60 \(\pm\) 1.89 & 2.50 \(\pm\) 1.18 \\ \hline \begin{tabular}{l} Anteroposterior skeletal \\ pattern \\ \end{tabular}  & Class I & 3071.95 \(\pm\) 1142.58 & 33.05 \(\pm\) 4.91 & 19.36 \(\pm\) 2.87 & 2.88 \(\pm\) 1.26 * \\ \cline{2-6}  & Class II & 2994.61 \(\pm\) 908.68 & 31.37 \(\pm\) 4.92 & 19.44 \(\pm\) 1.97 & 2.32 \(\pm\) 1.09 \\ \cline{2-6}  & Class III & 4161.80 \(\pm\) 1335.24 * & 32.14 \(\pm\) 5.10 & 19.36 \(\pm\) 1.88 & 4.57 \(\pm\) 2.00 * \\ \hline Vertical skeletal pattern & Hypodivergent & 2900.99 \(\pm\) 970.53 & 33.19 \(\pm\) 5.33 & 19.05 \(\pm\) 2.06 & 2.87 \(\pm\) 1.38 \\ \cline{2-6}  & Normodivergent & 3029.86 \(\pm\) 1026.29 & 31.43 \(\pm\) 4.53 & 19.42 \(\pm\) 2.90 & 2.56 \(\pm\) 1.27 \\ \cline{2-6}  & Hyperdivergent & 3553.62 \(\pm\) 1244.88 * & 32.39 \(\pm\) 5.04 & 19.94 \(\pm\) 1.91 & 2.78 \(\pm\) 1.34 \\ \hline \multicolumn{6}{l}{* Significant difference vs. Egyptians. * Significant difference vs. Female. * Significant difference vs. If. * Significant difference vs. Hyodivergent. * Significant difference vs. Normodivergent. * Significant difference vs. Normodivergent. * Significant difference vs. * Significant difference vs. In terms of vertical skeletal pattern, differences were observed only in chin volume, with the chin volume in the hyperdivergent pattern being significantly greater than that of the hypodivergent and normodivergent patterns in the univariate analysis (Hypodivergent: 2900.99 \(\pm\) 970.53 and Normodivergent: 3029.86 \(\pm\) 1026.29, both \(p\) < 0.01 compared to the hyperdivergent: 3553.62 \(\pm\) 1244.88). Ordinal logistic regression analysis (Table 4) revealed that the vertical skeletal pattern was positively correlated with chin volume (B = 0.00, \(p\) = 0.00), and negatively correlated with chin width and chin depth (B = \(-\)0.26, \(p\) = 0.02). In terms of ethnicity, the Korean group showed significantly larger values for chin volume than the Egyptian group (3668.19 \(\pm\) 1297.25 vs. 2838.46 \(\pm\) 856.26, respectively, \(p\) < 0.01), but there were no significant differences in chin width, height, and depth (Table 2). In terms of gender, males showed significantly larger values than females for all parameters including chin width (34.36 \(\pm\) 4.61 vs. 30.61 \(\pm\) 4.63, respectively, \(p\) < 0.01), chin height (20.42 \(\pm\) 2.71 vs. 18.60 \(\pm\) 1.89, respectively, \(p\) < 0.01), chin depth (2.99 \(\pm\) 1.45 vs. 2.50 \(\pm\) 1.18, respectively, \(p\) < 0.01), and chin volume (3648.51 \(\pm\) 1106.16 vs. 2655.20 \(\pm\) 827.98, respectively, \(p\) < 0.01).