tooth neck

例句：

1. 1.He was examining the tooth neck of a broken tooth.
   他正在检查一颗断牙的齿颈部。
2. 2.The dentist had to remove the tooth neck and replace it with a crown.
   牙医不得不拔除齿颈部并换上一个冠。
3. 3. The patient's tooth neck was infected, requiring antibiotic treatment.
   患者的齿颈部感染了，需要抗生素治疗。