The evidence in the scientific literature suggests a success rate of between 85%-95% for root canal treatment, however each individual tooth may have several factors that raise or lower the lifespan of the tooth. A well done root canal in patient with good oral hygiene habits may last a lifetime.

Depends upon dentist. 1hr or less

How long a root canal lasts depends on many factors, including the condition of the tooth itself and the gums and bone around the tooth, as well as how well the patient takes care of the tooth afterwards.