Dad needs to have a root canal operation.

爸爸需要做牙根管治疗。

Sometimes a tooth with a root canal filling will change color.

牙根管补过的牙有时会变色。

Objective: To raise the efficiency of one-visit root canal therapy.

目的：探讨提高根管治疗一次法成功率的方法。

It was about as popular as a root canal. (Speaking of the bank bailout).

它就像牙根管一样普及。

AIM: To establish an evaluating mode for difficulty in root canal therapy.

前言：目的：建立根管治疗难度的评估模式。