A.呈斜方形,頰尖銳,舌尖鈍 B.呈斜方形,頰尖鈍,舌尖銳 C.呈長方形,頰尖銳,舌尖鈍 D.呈長方形,頰尖鈍,舌尖銳 E.呈長方形,頰尖鈍,舌尖鈍
A.下頜切牙牙冠窄小 B.下頜切牙牙根窄而扁 C.下頜切牙唇面光滑 D.下頜切牙舌面無明顯邊緣嵴 E.下頜切牙舌面有明顯軸嵴