title: Operating microscope improves negotiation of second mesiobuccal canals in maxillary molars.
abstract: This in vitro study investigated the prevalence, location, and pathway of the second mesiobuccal canal (MB-2) in 45 first and second maxillary molars using the operating microscope (OM). Initially location and negotiation of MB-2 were attempted without magnification. Teeth in which MB-2 was not located or could not be negotiated were further explored under OM. Roots where MB-2 could not be negotiated even with OM were cross-sectioned and inspected microscopically. Morphometric measurements were performed to map the location of MB-2. Without magnification an apparent MB-2 orifice was located in 42 teeth and the canal negotiated in 31 (69%). With OM one additional apparent MB-2 orifice was located, and five previously identified canals were negotiated (total 80%). The root cross-sections confirmed the absence of MB-2 in all nine teeth where it was not negotiated. Location of MB-2 varied randomly. In conclusion MB-2 can be negotiated in 80% of maxillary molars, although an orifice is apparent in 96% of the teeth. Ability to negotiate MB-2 is facilitated by OM.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Hacettepe University, Ankara, Turkey.
authors.forename: M O
authors.initials: MO
authors.lastname: Görduysus
authors.forename: M
authors.initials: M
authors.lastname: Görduysus
authors.forename: S
authors.initials: S
authors.lastname: Friedman
mesh_terms: D003786:Dental Pulp Cavity / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D003804:Dentin / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation; D008437:Maxilla; D008853:Microscopy / Q000295:instrumentation*; D008963:Molar / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D009811:Odontometry; D011670:Pulpectomy / Q000379:methods; D011859:Radiography; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D014092:Tooth Root / Q000033:anatomy & histology