A 洞底要平,洞底轴壁与髓壁相交形成的轴髓线角不应过于锋锐 B
洞底洞形要有一定的深度 C
邻<img border="0" alt="" src="https://img.weimei168.com/uploads/upimg/20230104/2859002_0.jpg">洞应制成阶梯状 D
邻<img border="0" alt="" src="https://img.weimei168.com/uploads/upimg/20230104/2859002_0_1.jpg">洞邻面部分龈壁应做成斜向龈方的斜面 E
去除薄壁弱尖