Comparison of three techniques for preparing oval-shaped root canals.

Introduction: This study compared three techniques for preparing oval-shaped root canals: Anatomic Endodontic Technology (AET), hand instruments (Hedström files; Dentsply Maillefer, Ballaigues, Switzerland), and rotary nickel-titanium (EndoWave; Morita, Osaka, Japan) instruments with regard to cleaning ability and final canal shape.

Methods: Three groups each of 13 extracted human mandibular premolars with oval-shaped canals were used. After canal preparation, teeth were sectioned at three levels (coronal, middle, and apical), photographed to assess cross-sectional canal shape, and processed for histologic evaluation of canal wall planing and the presence of debris.

Results: None of the techniques resulted in completely prepared and cleaned canals. No significant difference was found among the three techniques with regard to untouched surface, cross-sectional area, remaining fins, and canal shape at the three levels. Rotary NiTi instruments resulted in significantly less debris in the apical third compared with AET and hand instrumentation.

Conclusions: AET did not perform better than rotary NiTi or hand instruments in oval-shaped canals.