Effect of Different Instrumentation Techniques on Vertical Root Fracture Resistance of Endodontically Treated Teeth.

Statement Of The Problem: Vertical root fractures are catastrophic events that often result in tooth extraction. Many contributing factor are associated with increasing incidence of vertical root fracture. Root canal preparation is one of the predisposing factors which can increase the root susceptibility to vertical fracture.

Shaping ability of 4 different single-file systems in simulated S-shaped canals.

Introduction: The aim of this study was to compare the shaping ability of 4 different single-file systems in simulated S-shaped canals.

Methods: Sixty-four S-shaped canals in resin blocks were prepared to an apical size of 25 using Reciproc (VDW, Munich, Germany), WaveOne (Dentsply Maillefer, Ballaigues, Switzerland), OneShape (Micro Méga, Besançon, France), and F360 (Komet Brasseler, Lemgo, Germany) (n = 16 canals/group) systems. Composite images were made from the superimposition of pre- and postinstrumentation images.

Influence of operator's experience level on lifespan of the WaveOne Primary file in extracted teeth.

Objectives: The aim of this study was to assess the influence of operator experience level on the lifespan of the WaveOne Primary file (Dentsply Maillefer, Ballaigues, Switzerland) in extracted teeth.

Materials And Methods: Moderately curved canals of extracted maxillary and mandibular molars were randomly distributed into 2 groups: experienced and inexperienced operators. Ten files were allocated to each group (n = 10).