title: Consistency of apex locator function: a clinical study.
abstract: The consistency of apex locators was determined by calculating the dysfunction frequency. Electronic working length (EWL) was determined in 507 patients requiring endodontic treatment. Different clinical parameters were recorded including tooth vitality, presence of obliteration, and metallic restoration. Two apex locators were used (Root ZX [Morita, Tokyo, Japan] and Raypex5 [VDW, Munich, Germany]). Apex locator performance was considered "consistent" when the scale bars were stable and moved only in correspondence to the movement of file in the root canal. A working length radiograph with files set to the EWL was performed. EWL were considered "acceptable" when the file tip was located 0 to 2 mm short of the radiographic apex. The function of apex locators was consistent in 85% of the patients (429/507 [99% confidence interval, 80-88]). The inconsistent measurements were strongly associated with partially or totally obliterated root canals (p < 0.0001). Radiographically, 97% of consistent measurements were "acceptable."
authors.affiliation: Department of Conservative Dentistry and Endodontology, University of Tübingen, Tübingen, Germany. Ashraf.ElAyouti@med.uni-tuebingen.de
authors.forename: Ashraf
authors.initials: A
authors.lastname: ElAyouti
authors.forename: Eleftheria
authors.initials: E
authors.lastname: Dima
authors.forename: Julia
authors.initials: J
authors.lastname: Ohmer
authors.forename: Kristina
authors.initials: K
authors.lastname: Sperl
authors.forename: Christiane
authors.initials: C
authors.lastname: von Ohle
authors.forename: Claus
authors.initials: C
authors.lastname: Löst
mesh_terms: D000328:Adult; D055615:Electrical Equipment and Supplies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009811:Odontometry / Q000295:instrumentation*; D019227:Tooth Apex / Q000033:anatomy & histology*; D055815:Young Adult