1. 根锥顶：Root angle tilt 齿根角倾斜 | Root apex 根锥顶 | Root apex beyond crossing point 根锥顶至相错点的距离
2. 根头：root activity 根活力 | root apex 根头 | root cap 根冠
3. 根锥顶点：等高齿弧齿锥齿轮 spiral gear with duplex tapered teeth | 根锥顶点 root apex | 曲线齿锥齿轮 curved tooth bevel gear
4. 根尖：Root canal 根管 | Root apex根尖 | Apical foramen根尖孔