Comparison of effectiveness and safety between Twisted File technique and ProTaper Universal rotary full sequence based on micro-computed tomography / 北京大学学报(医学版)

ABSTRACT

Objective:To evaluate the efficacy and security of two type of rotary nickel titanium system (Twisted File and ProTaper Universal)for root canal preparation based on micro-computed tomography (micro-CT).Methods:Twenty extracted molars (including 62 canals)were divided into two experimen-tal groups and were respectively instrumented using Twisted File rotary nickel titanium system (TF)and ProTaper Universal rotary nickel titanium system (PU)to #25/0.08 following recommended protocol. Time for root canal instrumentation (accumulation of time for every single file)was recorded.The 0-3 mm root surface from apex was observed under an optical stereomicroscope at 25 ×magnification.The presence of crack line was noted.The root canals were scanned with micro-CT before and after root canal preparation.Three-dimensional shape images of canals were reconstructed,calculated and evaluated. The amount of canal central transportation of the two groups was calculated and compared.Results:The shorter preparation time [(0.53 ±0.1 4)min]was observed in TF group,while the preparation time of PU group was (2.06 ±0.39)min (P<0.05).In mid-root level,TF group shaping resulted in less ca-nal center transportation than PU group [(0.070 ±0.056)mm vs.(0.097 ±0.084)mm,P<0.05]. No instrument separation was observed in both the groups.Cracks were not found in both the groups ei-ther based in micro-CT images or observation under an optical stereomicroscope at 25 × magnification. Conclusion:Compared with ProTaper Universal,Twisted File took less time in root canal preparation and exhibited better shaping ability,and less canal transportation.