title: Evaluation of an improved endodontic teaching model: do preclinical exercises have an influence on the technical quality of root canal treatments?
abstract: OBJECTIVE
  To investigate whether the preclinical application of an electronic root canal length measurement device (ERCLMD) leads to more accurate working length (WL) determinations in a preclinical endodontic course and if this exercise effects the technical quality of root canal procedures when treatments are performed on patients for the first time.
  
  
  METHODS
  Root canal treatments performed by two consecutive groups of third year students (group 1: n = 39, group 2: n = 44) were compared in the preclinical course and when root canal treatments were performed on patients in the following term. Two different teaching models were applied in the preclinical endodontic course. WL in group 1 was determined with radiographs only. The teaching model applied in group 2 allowed the application of an ERCLMD. When treatments were performed on patients, both groups used the same technique to determine WL. It was first determined using an ERCLMD and verified radiographically. Master cone and root filling lengths were evaluated using radiographs, and comparisons between both groups were made using Fischer's exact test.
  
  
  RESULTS
  Root fillings performed by students of group 2 were more often classified as acceptable. This observation was made in the preclinical endodontic course and when treatments were performed on patients.
  
  
  CONCLUSIONS
  The application of an ERCLMD in combination with radiographs is more accurate to determine WL than radiographs alone. Students practiced the use of ERCLMDs with the new model and benefited from this experience when performing their first root canal treatments on patients.
authors.affiliation: Department of Operative Dentistry and Periodontology, Faculty of Dentistry, University Medical Centre, Freiburg, Germany.
authors.forename: J P
authors.initials: JP
authors.lastname: Tchorz
authors.forename: P A
authors.initials: PA
authors.lastname: Ganter
authors.forename: J P
authors.initials: JP
authors.lastname: Woelber
authors.forename: S
authors.initials: S
authors.lastname: Stampf
authors.forename: E
authors.initials: E
authors.lastname: Hellwig
authors.forename: M J
authors.initials: MJ
authors.lastname: Altenburger
mesh_terms: D004497:Education, Dental / Q000379:methods*; D004708:Endodontics / Q000193:education*; D006801:Humans; D012390:Root Canal Therapy; D013335:Students, Dental
keywords: apex locator; electronic root canal measurement device; endodontic teaching; working length determination