title: [Comparative study of shaping ability between rotary ProTaper and Flexofile].
abstract: OBJECTIVE
  To compare the shaping ability of rotary ProTaper and Flexofile in simulated resin root canals.
  
  
  METHODS
  Forty simulated resin root canals were randomly assigned to two groups, one group for rotary ProTaper with crown-down technique and the other for Flexofile with balanced force technique. Change of working length and incidence of canal aberration and instruments failure were recorded. After preparation, the change of root canal curvature and the amount of resin removed at the inner and outer canal walls were measured with Image Pro Plus 5.0. The centring ability and total amount of resin removed were also assessed.
  
  
  RESULTS
  In the model of simulated resin canals, ProTaper instruments maintained working length better. Canals prepared with ProTaper instruments remained better curvature and showed fewer aberration compared with those prepared with Flexofile (P < 0.01). ProTaper instruments performed a better centring ability.
  
  
  CONCLUSIONS
  ProTaper instruments have a better shaping ability in simulated resin root canals.
authors: Key. Laboratory of Oral Biomedical Engineering of Ministry of Education, Sichuan University, Chengdu 610041, China.
authors: Guo-bin
authors: GB
authors: Yang
authors: Yu-lu
authors: YL
authors: Zheng
authors: Wei-qun
authors: WQ
authors: Xu
authors: Hao-lai
authors: HL
authors: Li
authors: Hong-kun
authors: HK
authors: Wu
mesh_terms: D003722:Dental Alloys; D003762:Dental Instruments; D003786:Dental Pulp Cavity; D004867:Equipment Design; D006801:Humans; D009532:Nickel; D018915:Root Canal Preparation; D012390:Root Canal Therapy; D014025:Titanium
chemical_list: D003722:Dental Alloys; D009532:Nickel; D014025:Titanium