Surface nanoscale profile of WaveOne, WaveOne Gold, Reciproc, and Reciproc blue, before and after root canal preparation.

This study aimed to compare the surface topographies and nanoscale profiles of intact and used WaveOne, WaveOne Gold, Reciproc, and Reciproc blue nickel-titanium (NiTi) instruments. Sixteen NiTi instruments were evaluated; four from each one of WaveOne (25/0.08), WaveOne Gold (25/0.07), Reciproc (25/0.08), and Reciproc blue (25/0.08) files. Each instrument was used to prepare four curved canals. A three-dimensional nanoscale surface profiler was used to assess instrument surfaces before and after root canal instrumentation. The data were analyzed with one-way analysis of variance using SPSS 21.0 software and set significance at P < 0.05. There were significant differences in surface topography between NiTi instruments. Intact WaveOne and WaveOne Gold instruments had the highest values, followed by the Reciproc and Reciproc blue instruments (P < 0.05). Used WaveOne and WaveOne Gold instruments had the highest values, followed by Reciproc and Reciproc blue instruments (P < 0.05). Some indications of microcracks in qualitatively intact Reciproc blue files were observed, and minor surface cracks in used WaveOne Gold instruments were also observed. Used WaveOne, Reciproc, and Reciproc blue instruments exhibited cracks and microcavities. WaveOne Gold and Reciproc blue instruments had significantly higher levels of surface distortion after root canal instrumentation, and WaveOne exhibited the lowest level of surface deformation. Each of the Reciprocating instruments was safely used to prepare four canals without incident. The three-dimensional stylus profiler provided valuable assessments of the surface topographies of NiTi instruments.