title: The fourth canal: its incidence in maxillary first molars.
abstract: The purpose of this study was to determine the frequency with which a fourth canal is clinically located, instrumented and obturated in maxillary first molars. The results indicate that it can be located, instrumented and filled at least 77 per cent of the time. This is an important finding for the general practitioner and endodontist alike, as clinical success is directly related to the complete debridement and obturation of the root canal system.
authors.affiliation: University of British Columbia.
authors.forename: B M
authors.initials: BM
authors.lastname: Henry
mesh_terms: D003737:Dental Cavity Preparation / Q000295:instrumentation / Q000706:statistics & numerical data; D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D006801:Humans; D008437:Maxilla; D008963:Molar / Q000033:anatomy & histology*; D012390:Root Canal Therapy / Q000295:instrumentation / Q000706:statistics & numerical data; D014092:Tooth Root / Q000033:anatomy & histology*