Cleaning efficacy of different root canal preparation systems and irrigation regimens

PurposeTo compare the cleaning efficacy of root canal walls after using two Nickel–Titanium (Ni–Ti) rotary files (Flexmaster and Mtwo) and one hand Ni–Ti file (Ni–Ti flex-K) when associated with different final irrigation regimens (SmearClear, 17% ethylene diamine tetra acetic acid (EDTA) and sodium hypochlorite).Materials and methodsNinety extracted human premolars with similar range of canal curvature (21–39°) were selected. After crown removal and working length determination, roots were divided into three equal groups according to root canal instrumentation: Group I and Group II were prepared using Flexmaster, Mtwo Ni–Ti rotary systems respectively where Group III was prepared using hand NiTi flex-K files. Each group was further subdivided into three equal subgroups according to root canal final irrigation; subgroup A: SmearClear, subgroup B: 17% EDTA and subgroup C: NaOCl. Roots were then splitted longitudinally and processed for scanning electron microscopic (SEM) examination to evaluate and score the root canal cleanliness.ResultsFinal root canal irrigation using either SmearClear or 17% EDTA had significantly better cleaning efficiency than that of NaOCl in all tested groups. Ni–Ti hand files had significantly less cleaning efficacy than that of rotary systems except in subgroup C using NaOCl.