A Digital Microscopic Evaluation of the Induction of Dentinal Micro-cracks after Canal Preparation with Rotary and Reciprocating NiTi Systems in vitro

Aim of the Study: This study aims to assess the induction of dentinal microcracks by different NiTi systems and to compare rotary and reciprocating systems.

Methodology: Fifty teeth were selected and divided into five groups. Each group was instrumented according to the manufacturer's specifications and was performed by a single operator. The teeth were then sectioned and viewed under a digital microscope. The study aimed to compare the performance of four different instruments.

Results: No cracks were detected in the control group. The Hyflex EDM produced the highest number of cracks in 4mm (70%), and the highest number of cracks in total (43.3%). ProTaper Universal produced the least number of cracks (16.6%). WaveOne and WaveOne Gold both produced cracks (30%).

Conclusion: Within the limitation of this in vitro study, all the instruments produced microcracks. The Hyflex EDM produced higher cracks in the mid-root section. There was no significant difference in the incidence of microcracks between the four systems or between rotary and reciprocating systems.