Linked from
The 8 pages that link to Root canal treatment, each with the reason it gives.
MolarRelated: It can preserve a molar whose pulp is damaged by decay or injury.
ToothRelated: It can preserve a tooth whose pulp is irreversibly inflamed or infected.
Tooth decayRelated: It can preserve a tooth when decay has reached and damaged its pulp.
DentistRelated: Dentists use it to preserve teeth with damaged pulp.
ToothacheRelated: It can preserve a tooth when pulp damage causes persistent pain.