title: [In vitro comparison of an electronic root canal length measuring device and the radiographic determination of working length].
abstract: The objective of this study was to evaluate the accuracy of an electronic root canal length measuring device (AFA Apex Finder, Analytic Technology, Orange, USA) and to compare the results with those obtained using handfiles evaluated radiographically using 146 extracted teeth with mature single roots. Root canal lengths were determined electronically with files cemented to their lengths. A radiograph in long cone technique with the inserted root canal instrument was performed. The apical point of working length was determined 1 mm coronally of the radiographic apex. The apical part of root surfaces was removed to expose the root canal with the inserted probe tip. The distance between measuring file tip and the apical constriction was measured using a microscope. In 77.2% of the evaluated radiographs the determined apical point of working length was found in a range of +-0.5 mm from the apical constriction. In 98.5% of the results of electronic determination of working length, the distance between file tip and the apical constriction was less than 0.5 mm. The electronic root canal length measuring device provided significantly more accurate results than the radiographs.
authors.affiliation: Universitätsklinikum Benjamin Franklin, Poliklinik für Zahnerhaltungskunde und Parodontologie, Assmannhauserstr. 4-6, D-14197 Berlin. opommer@zedat.fu-berlin.de
authors.forename: O
authors.initials: O
authors.lastname: Pommer
mesh_terms: D003786:Dental Pulp Cavity / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D004582:Electronics, Medical; D006801:Humans; D011861:Radiography, Dental; D018915:Root Canal Preparation / Q000295:instrumentation; D012390:Root Canal Therapy; D019227:Tooth Apex / Q000000981:diagnostic imaging