A study on FlexMaster : a Ni-Ti rotary engine driven system for root canal preparation.

Area of Science:

• Endodontics
• Dental Materials Science

Background:

• Root canal preparation aims to clean and shape the canal system.
• Nickel Titanium instruments offer flexibility and efficiency in endodontic procedures.
• Evaluating new rotary systems against established hand files is crucial for clinical practice.

Purpose of the Study:

• To compare the cleaning and shaping effectiveness of the Nickel Titanium FlexMaster engine-driven system with Nickel Titanium Flexofile hand instruments.
• To assess the time efficiency and procedural errors associated with each instrumentation technique.

Main Methods:

• 40 curved root canals (20-30 degrees) were divided into two groups: FlexMaster (rotary, crown-down) and Flexofile (hand, conventional/step-back).
• Irrigation with 5.25% sodium hypochlorite and 17% EDTA was performed.
• Preparation time and instrument separation were recorded.
• Longitudinal sections were examined under a scanning electron microscope for debris and smear layer in the apical region using a 5-score scale.

Main Results:

• Neither system achieved completely clean root canals or maintained original canal uniformity.
• Manual Flexofile technique resulted in significantly less apical debris and smear layer (p<0.05).
• FlexMaster instrumentation was significantly faster (p<0.01), but one file separated in a curved canal.

Conclusions:

• Manual Flexofile hand instrumentation demonstrated superior cleaning of the apical root canal region compared to the FlexMaster rotary system.
• While faster, the FlexMaster system was less effective in removing debris and smear layer.
• Both systems failed to completely clean and maintain the original canal morphology.