Root canal shaping by single-file systems and rotary instruments: a laboratory study

Area of Science:

• Endodontics
• Dental Materials Science
• Biomaterials

Background:

• Root canal treatment aims to clean and shape the root canal system.
• Severely curved root canals present challenges for instrumentation.
• Evaluating novel instrumentation techniques is crucial for improving endodontic outcomes.

Purpose of the Study:

• To compare the shaping ability of two single-file systems (WaveOne, Reciproc) against conventional rotary instruments (ProTaper).
• To assess instrumentation time, instrument separation, and canal morphology changes in curved root canals.

Main Methods:

• 120 mandibular molars with severe curvature were divided into three groups (n=40).
• Instrumentation was performed using WaveOne, Reciproc, or ProTaper systems.
• Working length, canal curvature, preparation time, and instrument integrity were evaluated.

Main Results:

• Single-file systems reduced preparation time by approximately 50% compared to ProTaper.
• No instrument separation occurred with WaveOne or Reciproc, while two ProTaper instruments fractured.
• All systems showed reduction in working length and canal straightening, with ProTaper showing the highest scores.

Conclusions:

• Single-file systems offer significant time savings and reduced instrument separation in curved root canals.
• WaveOne and Reciproc demonstrate efficient shaping capabilities with favorable safety profiles.
• While ProTaper showed greater canal straightening, single-file systems provide a viable alternative for complex root canal anatomy.