Fatigue Of Nickel Titanium File After The Bending Root Tube Was Completed And Research On The Localization Of Root Canal

Objective:In this study,three different niti files were used to prepare the resin simulated root canal.Used Adobe Photo Shop CS5 and other image software to compare and analyze the fatigue resistance and center positioning ability of niti files.To provide theoretical guidance for the selection of the most ideal niti instalments in clinical practiceMethods:Choosed a single-bent transparent resin to simulate a root canal of 45 pieces into three groups are used(15 each group).The resin is used to simulate the root canal knife engraving number.Drawn a line as a positioning mark.First used 10#C file to unblock the resin root canal.Then used the syringe to absorb distilled water to rinse the root canal clean,and dried the root canal with an appropriate moisture absorption paper tip.Wave One(Wave One Primary)niti file,ProTaper Next niti file and TF(Twisted file)niti file were used for resin canal preparation respectively.The central positioning ability of the three instruments was evaluated based on the results of the medial resin removal and the lateral resin removal.At the same time,check and record the deformation and fracture of the instrument after the preparation of nickel-titanium file to judge the fatigue resistance.Record the preparation time in the experimentResults:The instrument deformation rate and fracture rate of TF ni-ti file are higher.After three kinds of niti files were prepared,the amount of endodontic wall resin removal was measured and compared.It was concluded that the amount of endodontic wall resin removal was the largest in Wave One group,followed by ProTaper Next group and the least in TF group.The differences of the three groups were statistically significant.The amount of resin removed from the lateral wall of the root canal after the preparation of three kinds of niti files was measured and compared.It was concluded that the amount of resin removed from the lateral wall of the root canal was the largest in Wave one group,followed by ProTaper Next group and the least in TF group.The differences of the three groups were statistically significant.1,2mm away from the root tip,the center positioning ability of the Wave One group and the ProTaper Next group was better.3 mm away from the root ti to the upper end of the root canal,pthe center positioning ability of the TF group was better,followed by the ProTaper Next group,and the Wave One group was the worst,and the differences of the three groups were statistically significant.Compared with three kinds of niti files,the results showed that TF file took the longest time,followed by ProTaper Next file,and Wave One file was the shortest.Conclusion:TF niti file has poor fatigue resistance,good positioning ability in the middle and upper part of the root canal,and relatively small cutting amount to the root canal wall,but it takes a long time to prepare the root canal.ProTaper Next ni-ti file has better ability to locate the center of the root tip,has less cutting on the root canal wall,and takes longer time to prepare the root canal.Wave One niti file has better ability to locate the center of the root tip,has the largest cutting amount to the root canal wall,and takes the shortest time to prepare the root canal.ProTaper Next has the best ability to locate the center of the most easily displaced root canal in the process of curved root canal preparation.The three kinds of niti files have their own advantages and disadvantages in performance.Clinicians could choose to use them according to their own needs.