In Vitro Qualitative Evaluation of Root-End Preparation Performed by Piezoelectric Instruments.

Area of Science:

• Endodontic Surgery
• Dental Materials Science

Background:

• Ultrasonic devices are crucial for effective root canal debridement in endodontic surgery.
• Concerns exist regarding potential crack formation during ultrasonic root-end retropreparation due to incorrect settings or tip wear.

Purpose of the Study:

• To investigate the correlation between ultrasonic root-end preparation and the incidence of root cracks.
• To evaluate the effect of ultrasonic instrumentation on pre-existing cracks and the integrity of root structures.

Main Methods:

• Human teeth extracted for periodontal reasons were used for in vitro analysis.
• Roots underwent root canal treatment, resection, and ultrasonic retropreparation using a piezoelectric device at maximum power.
• Teeth were analyzed pre- and post-procedure for cracks and preparation morphology using stereomicroscopy; tips were examined via SEM.

Main Results:

• No new cracks were observed in teeth initially free of cracks after ultrasonic retropreparation.
• The average preparation time was 1 minute and 54 seconds.
• SEM analysis revealed minimal wear on piezoelectric tips after multiple uses, and no tips fractured during the procedure.

Conclusions:

• The tested ultrasonic piezoelectric system does not appear to be a significant cause of new root crack formation.
• Pre-existing cracks in teeth may be susceptible to expansion during ultrasonic root-end preparation.