Root Canal Preparation With The NiTi Systems TF And ProTaper

TF is a recently introduced NiTi engine-file manufactured with a twisting method. It was reported to have a higher fracture resistance than ground files. The manufacturer claimed that TF has a different surface texture (natural grain structure) that runs in the longitudinal direction and that the instrument is made of the R-phase of NiTi alloy (although no transition temperature data are presented). It was further claimed that these features serve to raise the flexibility and the fracture resistance of the instrument. There is also an absence of transverse-running machining marks (as a result of electropolishing) that would result in slower crack initiation and propagation.There have been few studies published to date on the ability of the TF and the ProTaper to maintain canal curvature. The aim of the present study was to compare root canal transportation and canal centering ability between traditionally ground NiTi rotary instruments and the TF on root canals presenting a severe curvature.Part1Shaping ability of TF and ProTaper rotary Ni-Ti instrument in simulated root canalsAim The aim of this paper was to to compare the shaping ability of the nickel-titanium (NiTi) systems TF and ProTaper in simulated root canals.Methodology Twenty curved artificial root canals were selected. All canals were prepared to size25taper with two systems. The pre-and post-instrumentation images were recorded and assessment of the canal shape was completed with Photoshop7.0. The width of resin removed was measured at10measuring points. Incidence of canal aberrations, instrument fracture and preparation time were recorded. The data were analyzed statistically using ANOVA.Results TF group prepared canals more rapidly (P＜0.01) than ProTaper group. One ProTaper instrument separated. ProTaper instruments removed more resin from the outside of the curvature at the apical thirds and coronal thirds, and removed more material from the middle and apical thirds on the outer canal wall.Conclusion Both two instruments were well in prepared curved canals. No significant differences were found in the preparation length, transportation or taper. TF instruments showed better centering ability than ProTaper. Part2Root canal preparation with the NiTi systems TF and ProTaperAim:The aim of this paper was to examine the result of rotary root canal preparation with the nickel-titanium (NiTi) systems TF and ProTaper.Methodology:Thirty mesial canals of human mandibular molars were selected. All canals were prepared to size25taper with two systems. The pre-and post-instrumentation images were recorded and assessment of the canal shape was completed with Photoshop7.0. The width of dentine removed was measured at9measuring points. Incidence of canal aberrations, instrument fracture and preparation time were recorded. The data were analyzed statistically using T-test.Results:TF group prepared canals more rapidly (P＜0.05) than ProTaper group. One ProTaper instrument separated. ProTaper instruments removed more dentine from the outside of the curvature at the apical thirds than TF.Conclusions:Both two instruments were well in prepared curved canals. No significant differences were found in the preparation length, transportation or taper. There was no significant difference in centering ability between TF and ProTaper in preparing human mandibular molars.