title: An ex vivo comparison of working length determination by three electronic root canal length measurement devices integrated into endodontic rotary motors.
abstract: OBJECTIVE
  The objective of this study was to compare the accuracy of working length (WL) determination by X-Smart Dual, ENDOAce, and Gold Reciproc motor, in manual mode and mechanical preparation set to auto apical reverse (AAR) mode.
  
  
  METHODS
  Forty-five anterior teeth were included in the study. The canal length was determined by introducing #10 file into the canal until it emerged at the apical foramen. The incisal edges were adjusted to obtain 18 mm standard length. The teeth were embedded in Plexiglas tubes, filled with alginate, and measured in manual and AAR modes.
  
  
  RESULTS
  Within and between the groups, there was no significant difference in WL measurements, both in manual and AAR modes. In the X-Smart Dual group, all manual measurements were within root canal limits, while 13 % of AAR mode measurements were recorded when the file tip passed the apical foramen. In the ENDOAce group, 13 and 7 % of the measurements, in manual and AAR modes respectively, were recorded when the file tip passed the foramen. In the Gold Reciproc motor group, 27 and 33 % of the measurements, in manual and AAR modes respectively, were recorded when the file tip passed the foramen.
  
  
  CONCLUSIONS
  With the limitation of this ex vivo study, the tested devices presented no significant differences in length measurements and were within the clinical accepted margin of error.
  
  
  CONCLUSIONS
  Mechanical preparation must be confined to the root canal system. The adverse results of overinstrumentation emphasize the need to reconsider the ±0.50 mm margin of error that is clinically acceptable for WL measurements.
authors.affiliation: Endodontics and Dental Traumatology Department, Graduate School of Dentistry, Rambam Health Care Campus, Haifa, Israel. manalmaree@yahoo.com.
authors.forename: Manal Maree
authors.initials: MM
authors.lastname: Ali
authors.affiliation: Department of Endodontology, The Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Ronald
authors.initials: R
authors.lastname: Wigler
authors.affiliation: Endodontics and Dental Traumatology Department, Graduate School of Dentistry, Rambam Health Care Campus, Haifa, Israel.|Rappaport Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel.
authors.forename: Shaul
authors.initials: S
authors.lastname: Lin
authors.affiliation: Endodontics and Dental Traumatology Department, Graduate School of Dentistry, Rambam Health Care Campus, Haifa, Israel.|Department of Endodontology, The Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Arieh Y
authors.initials: AY
authors.lastname: Kaufman
mesh_terms: D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D055615:Electrical Equipment and Supplies; D004867:Equipment Design; D006801:Humans; D066298:In Vitro Techniques; D009811:Odontometry / Q000295:instrumentation*; D018915:Root Canal Preparation / Q000295:instrumentation*; D014092:Tooth Root / Q000033:anatomy & histology*
keywords: ENDOAce; Electronic root canal length measurement devices; Gold Reciproc motor; Working length; X-Smart Dual