title: In vitro evaluation of the reliability of the Root ZX electronic apex locator.
abstract: OBJECTIVE
  An experimental comparison of the Root ZX apex locator with the real measurement of the root canal length was carried out using a saline gel to simulate the periodontium.
  
  
  METHODS
  Lengths were taken when the needle reached the 0.5 mark and the Apex mark on the meter. These measurements were then compared with a calculated reference length representing the real length of the root canal. Reliability was assessed using Student's t-test. Precision was assessed using the mean and standard deviation of differences.
  
  
  RESULTS
  The Root ZX gave measurements within a range of 0.5 mm in 84.72% of the cases. The intra-operator and inter-operator variabilities were not statistically significant (P > 0.05).
  
  
  CONCLUSIONS
  The Root ZX is not capable of detecting the '0.5 mm from the foramen' position and thus, should only be used to detect the foramen (major diameter).
authors.affiliation: Endodontic Department, St Joseph University, Beirut, Lebanon. janus@cyberia.net.lb
authors.forename: H F
authors.initials: HF
authors.lastname: Ounsi
authors.forename: A
authors.initials: A
authors.lastname: Naaman
mesh_terms: D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000033:anatomy & histology; D005069:Evaluation Studies as Topic; D006801:Humans; D015588:Observer Variation; D009811:Odontometry / Q000295:instrumentation; D015203:Reproducibility of Results; D012390:Root Canal Therapy / Q000295:instrumentation*; D019227:Tooth Apex; D014092:Tooth Root / Q000033:anatomy & histology