Acomparati ve study of deformation and fracture of two rotar y nikel titanium instruments after simulat ed clinical use (in vitro)‎

الملخص EN

This in-vitro investigation was designed to form a simulated clinical use using RaCe rotary system and HERO Shaper rotary system and check for the deformation and fracture after each use of files using loupe and Dental Operating Microscope (DOM).

A total of 100 mesiobuccal root canals from lower 1st molars were used.

They were with average medium curve from 200 to 400 determined according to Schneider method.

Samples were classified into groups I and II.

Group I consists of 50 root canal prepared by RaCe rotary system.

Group II consists of 50 root canal prepared by HERO Shaper rotary system.

No fracture occurred in this study.

Deformations were detected in the MAF assigned for examination as follows: In group I (RaCe): 4 MAF were deformed out of 10, 2 of the files were detected by the loupe and all of them were detected by the DOM.

In group II (HERO Shaper): 5 MAF were deformed out of 10, 1 of the files was detected by the loupe and all of them were detected by the DOM.

There was no statistical difference between the 2 systems regarding deformation.