RESUMEN
INTRODUCTION: The aim of this study was to compare by scanning electron microscopy the presence of smear layer and debris on root canal walls after preparation with the single-file system WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) versus the rotary ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) under 2 final irrigant regimens. METHODS: Forty freshly extracted single-rooted human teeth were randomly divided into 4 groups (n = 10). The ProTaper and ProTaper and rotary CanalBrush (Coltène Whaledent GmbH+ Co KG, Langenau, Germany) groups were instrumented with the ProTaper system. Groups WaveOne and WaveOne and rotary CanalBrush were instrumented with the WaveOne system. The irrigant in all groups was 2 mL 5.25% sodium hypochlorite (NaOCl) solution, whereas the final irrigation after preparation in the ProTaper and WaveOne groups was 1 mL Smear Clear solution (Sybron Endo, Orange, CA) and then 5.25% NaOCl applied with a plastic syringe, and in the ProTaper and rotary CanalBrush and WaveOne and rotary CanalBrush groups, it was 1 mL Smear Clear solution and then 5.25% NaOCl (rotary CanalBrush agitation). Roots were processed for scanning electron microscopic examination for debris and smear layer scoring. Data were statistically analyzed. RESULTS: All groups showed more efficient smear layer and debris removal coronally than in the middle and apical regions, whereas the mean total debris score and the mean smear layer score in all groups were less in the WaveOne and rotary CanalBrush groups than the ProTaper and rotary CanalBrush and the WaveOne and ProTaper groups. CONCLUSIONS: Using the rotary CanalBrush in canals prepared with WaveOne produced the cleanest canal walls, and the WaveOne system gave superior results compared with the ProTaper system.
