title: Effectiveness of a manual glide path on the preparation of curved root canals by using Mtwo rotary instruments.
abstract: BACKGROUND
  Nickel-titanium rotary instruments reduce procedural errors and the time required to finish root canal preparation. The goal of this study was to evaluate the effectiveness of a manual glide path on the preparation of curved root canals with Mtwo rotary system.
  
  
  METHODS
  Forty buccal root canals with angles of curvature between 25 to 76 degrees were randomly divided into 4 groups (n = 10); 2 groups were instrumented with Mtwo instruments to the full length, and in the other 2 groups a glide path with #08-15 K files was performed before instrumentation with Mtwo system. Digital double radiographic technique was used to determine apical transportation and the change in angle of curvature. Also working time was calculated.
  
  
  RESULTS
  No statistically significant differences in the angle of canal curvature, apical transportation, and the working time were found between groups with glide path and no glide path. No significant differences were found when comparing the results of 3 variables between degrees of curvature.
  
  
  CONCLUSIONS
  The use of a manual glide path before Mtwo rotary system did not influence the apical transportation in curved root canals.
authors.affiliation: Department of Dental Pathology and Therapeutics, School of Dentistry, University of Granada, Granada, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Uroz-Torres
authors.forename: María Paloma
authors.initials: MP
authors.lastname: González-Rodríguez
authors.forename: Carmen María
authors.initials: CM
authors.lastname: Ferrer-Luque
mesh_terms: D003722:Dental Alloys; D003786:Dental Pulp Cavity / Q000473:pathology; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008422:Materials Testing; D009532:Nickel; D019252:Radiography, Dental, Digital / Q000379:methods; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D012399:Rotation; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium; D019227:Tooth Apex / Q000473:pathology
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium