Root Dentine Strain Generation during Root Canal Instrumentation with Rotation and Reciprocation Motions

The aim of the study is to measure and compare strain generated on root dentine surface by two different instrumentation motions. Thirty extracted single canal premolars were used in this study which randomly was divided into two groups, one group was prepared with ProTaper NEXT X2 file in rotation motion, and the second group was prepared by WaveOne GOLD primary file in reciprocation motion, the canals were irrigated during canal preparation by 2 ml of sodium hypochlorite and 17% EDTA gel was used. Strain measurement was performed by strain gauges and a digital strain output reader, data were recorded every 5 s for 50 s. The results of this study have shown that WaveOne GOLD had higher mean 0.7308±0.41106 than ProTaper next 0.5385±0.39904 which means WaveOne GOLD generates greater strain than ProTaper NEXT. However, according to Student’s t-test between two groups there is no statistical difference between them. Based on the results of this study, there was no difference between the two motions; both motions generated strain on root dentine surface.