Have you ever heard of a root canal getting infected ?

Absolutely: Although highly successful, endodontic treatment may fail from time to time.

Root canal: Although not the desired outcome, re-infection does occur. Reasons for this can be the existence of lateral canals not been on x-rays. Extra canal spaces not seen or felt so not sealed during treatment. Final restorations may start leaking. Teeth may be cracked also allowing germs in to cause infection . One way patients can prevent reinfect ion is regular checkups with dentist.

Yes: As an endodontist, approximately 60% of the teeth i treat have had previous root canals and became reinfected. Most of the time the procedure can be redone. The chance of success depends on the condition of the tooth (i.e. Cracked, decayed), the previous materials used, and the quality of the initial treatment.