title: Radiographic versus electronic root canal working length determination.
abstract: OBJECTIVE
  The aim of this ex vivo study was to compare the accuracy of radiographic and electronic root canal length determination methods, compared with actual root canal length obtained with stereomicroscope.
  
  
  METHODS
  Thirty extracted single-rooted permanent teeth were used for this study. After access preparation, actual length (AL) of the root canal were determined for each tooth by inserting a #15 file until the tip of the file was visible at the apical foramen under a stereomicroscope. The radiographic working length determination was determined with a digital radiographic system and for the electronic measurement all teeth were embedded in an alginate model to test apex locator in-vitro. Data was analyzed using the descriptive statistic and intraclass correlation coefficient.
  
  
  RESULTS
  No significant difference was found between the radiographic and electronic root canal working length determination (P>0.05). The percentage of electronic measurements within ± 0.5 mm to the apical constriction was 93.34% and 90% for radiographic methods within ± 0.5 mm of all cases compared with AL.
  
  
  CONCLUSIONS
  The present ex vivo study showed that electronic root canal working length determination is not superior to radiographic methods. Both methods provided a good performance in determining the root canal working length.
authors.affiliation: Division of Preventive and Operative Dentistry, Endodontics, Pedodontics, and Minimally Invasive Dentistry, University Clinic of Dentistry and Maxillofacial Surgery, Medical University Graz, Austria. lumnije.kqiku@medunigraz.at
authors.forename: Lumnije
authors.initials: L
authors.lastname: Kqiku
authors.forename: Peter
authors.initials: P
authors.lastname: Städtler
mesh_terms: D003786:Dental Pulp Cavity / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D006801:Humans; D009811:Odontometry / Q000295:instrumentation*; D016300:Radiography, Bitewing / Q000379:methods*; D019252:Radiography, Dental, Digital / Q000379:methods; D018915:Root Canal Preparation / Q000295:instrumentation*; D019227:Tooth Apex / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D014092:Tooth Root / Q000033:anatomy & histology / Q000000981:diagnostic imaging