A comparison of molar root canal preparations using six instruments and instrumentation techniques

Area of Science:

• Endodontics
• Dental Materials Science
• Biomaterials Engineering

Background:

• Root canal preparation aims to clean and shape the root canal system.
• Instrument design and motion significantly influence preparation outcomes.
• Evaluating new endodontic instruments is crucial for improving treatment efficacy.

Purpose of the Study:

• To compare the canal preparation quality of six different endodontic instruments.
• To assess the impact of instrument type, blade design, and motion on canal shape.
• To evaluate instrumentation time for each instrument evaluated.

Main Methods:

• Six instrument types (Flexofile, Canal Master U, Heliapical, Flexogate, Ultraflex, Lightspeed) were tested on 240 mesial canals of mandibular molars.
• Roots were cross-sectioned at 2, 5, and 9 mm from the apex post-instrumentation.
• Canal preparation quality (round, oval, irregular) and instrumentation time were recorded.

Main Results:

• Nickel-titanium rotary instruments with short cutting blades yielded the best results.
• Canal Master U, Flexogate, and Lightspeed produced significantly more round canals than others.
• Lightspeed demonstrated the highest percentage of round canals; Canal Master U and Flexogate were significantly slower.

Conclusions:

• Rotary nickel-titanium instruments are superior for achieving rounder canal preparations.
• Lightspeed instrument offers optimal canal shaping quality among tested rotary systems.
• A trade-off exists between preparation efficiency and speed, with some faster instruments being less effective in shaping.