[Effects of different instruments in root-end preparation: scanning electron microscopic evaluation].

Area of Science:

• Endodontics
• Dental Materials Science

Background:

• Root-end preparation is crucial for endodontic surgery success.
• Minimizing procedural damage, such as micro-cracks, is essential for preserving tooth structure.
• Evaluating new technologies for improved preparation outcomes is ongoing.

Purpose of the Study:

• To compare the efficacy of ultrasonic retrotips versus traditional slow-speed handpieces in retrograde root-end preparation.
• To assess the impact of different ultrasonic instruments on micro-crack formation and cavity margin quality.

Main Methods:

• Twenty-seven maxillary second bicuspid teeth were randomly assigned to three preparation groups: ultrasonic diamond tip (Berutti/RE2), ultrasonic #40K file, and slow-speed handpiece.
• Root-end preparations were evaluated using scanning electron microscopy (SEM) for micro-cracks and cavity margin quality.
• Statistical analysis was performed using the Kruskal-Wallis test.

Main Results:

• Ultrasonic instruments generated significantly fewer micro-cracks than the slow-speed handpiece (P=0.002).
• The ultrasonic #40K file group demonstrated significantly superior cavity margin quality compared to the slow-speed handpiece group (P=0.039).
• No significant differences in micro-crack types or margin quality were observed between specific ultrasonic groups or between ultrasonic Berutti/RE2 and slow-speed handpiece groups.

Conclusions:

• Ultrasonic instruments are a feasible and effective option for retrograde root-end preparation.
• The use of ultrasonic technology can potentially reduce procedural complications like micro-crack formation.