title: Comparison of procedural errors resulting during root canal preparations completed by senior dental students in patients using an '8-step method' versus 'serial step-back technique'.
abstract: OBJECTIVE
  To compare procedural errors that occur in patients during root canal preparation by senior dental students using a new '8-step method' versus the traditional 'serial step-back technique.'
  
  
  METHODS
  Senior dental students treated 221 root canals of maxillary and mandibular teeth. Instrumentation included coronal flaring with Gates-Glidden reamers and standardized stainless steel K-files in all teeth. A new 8-step method was used to prepare 67 canals using standardized stainless steel hand instruments (8-step SS) and 69 canals using the rotary Nickel Titanium instruments (8-step NiTi). The traditional serial step-back technique (step-back) was used for 85 root canals. In the apical third, reaming or filing motions were used up to sizes 25 and only reaming motion in sizes larger than 25 with the new 8-step method. A filing motion was used in the step-back for all sizes. Root canals of all groups were obturated with gutta-percha points and AH26 using a lateral condensation technique. Pre- and postoperative radiographs were taken of each tooth. Procedural errors were recorded and statistically analyzed using a binomic test for comparison of proportion.
  
  
  RESULTS
  Procedural errors detected consisted of 2 canals with transportation (3%) with the 8-step SS, and 3 canals (4%) with transportation with 8-step NiTi. There were no canal obstructions or instrument separations. With the step-back, 20 canals were transported (24%), 7 canals had obstructions (8%), and in 1 canal instrument was separated (1%).
  
  
  CONCLUSIONS
  The new 8-step method resulted in fewer procedural errors than the traditional serial step-back technique when senior students prepared root canals in patients either by hand with standardized K-files or by rotary NiTi instrumentation.
authors.affiliation: Department of Endodontology, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel-Aviv University, Tel Aviv, Israel.
authors.forename: Anda
authors.initials: A
authors.lastname: Kfir
authors.forename: Esther
authors.initials: E
authors.lastname: Rosenberg
authors.forename: Offer
authors.initials: O
authors.lastname: Zuckerman
authors.forename: Aviad
authors.initials: A
authors.lastname: Tamse
authors.forename: Zvi
authors.initials: Z
authors.lastname: Fuss
mesh_terms: D001729:Bismuth / Q000627:therapeutic use; D003722:Dental Alloys; D003786:Dental Pulp Cavity / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D004338:Drug Combinations; D004708:Endodontics / Q000193:education*; D004853:Epoxy Resins / Q000627:therapeutic use; D004867:Equipment Design; D006171:Gutta-Percha / Q000627:therapeutic use; D006801:Humans; D019300:Medical Errors; D009532:Nickel; D011859:Radiography; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D012389:Root Canal Obturation; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D012834:Silver / Q000627:therapeutic use; D013193:Stainless Steel; D013335:Students, Dental; D014025:Titanium / Q000627:therapeutic use; D019227:Tooth Apex / Q000033:anatomy & histology / Q000000981:diagnostic imaging
chemical_list: D003722:Dental Alloys; D004338:Drug Combinations; D004853:Epoxy Resins; D012387:Root Canal Filling Materials; C040654:titanium nickelide; D013193:Stainless Steel; D012834:Silver; C028044:epoxy resin AH-26; D009532:Nickel; D006171:Gutta-Percha; D014025:Titanium; D001729:Bismuth