DOI: 10.36347/sjds.2019.v06i12.006

Pages: 524-531

A contact is established in between dentin surface and instrument inside the root canal, during cleaning and shaping. This creates a reaction torque in the instrument affecting its life span and also produce internal stresses in the dentin.Pecking motion,an in and out motion of instrument help in neutralizing these stresses.Different pecking depths affect the screw in forces generated in the instrument in different ways.Hence,the aim of this study was to evaluate the effect of various pecking depths of a rotating endodontic file on the screw-in forces generated while cleaning and shaping invivo. A total of 90 patients were selected and divided in to 6 groups. Cleaning and shaping was done by using Protaper Universal, Heroshaper and Two shape files with pecking depths of 4mm and 2mm.File distortion was seen under stereomicroscope. Scores were given and statistically analysed by Kruskal-Wallis test and Mann-whitney test. It was concluded that shorter pecking depth may cause lower file deformation when compared to longer pecking depth.