Simple root canals generally require one session lasting 30 minutes to an hour. However, if the dentist or endodontist suggests a permanent filling or crown for the tooth, serious cases can demand 90 minutes or more—or even a second visit. The number of Root canals that need cleaning and the kind of tooth that requires treatment are factors that affect how long does a root canal take time. Some teeth only have one root that needs to be treated, but others may have up to three. 

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