A 缺牙间隙的近、远中距正常及多个后牙连续缺失 B
缺牙区牙槽嵴骨吸收严重者 C
因邻牙向缺隙倾斜、移位,使缺隙牙<img border="0" alt="" src="https://img.weimei168.com/uploads/upimg/20230804/12260270_0.gif">龈距、近远中距减小者 D
对<img border="0" alt="" src="https://img.weimei168.com/uploads/upimg/20230804/12260270_0_1.gif">牙为牙周病Ⅱ度松动 E
外科手术后有颌骨及软组织缺损者