Pressure waves in root canals induced by Nd: YAG laser

Area of Science:

• Endodontics
• Biomedical Engineering
• Laser Dentistry

Background:

• Root canal preparation is evolving with new technologies.
• Laser-matter interaction can produce cavitation and pressure waves.
• Understanding these waves is crucial for endodontic procedures.

Purpose of the Study:

• To characterize pressure waves induced by Nd:YAG laser, sonic, and ultrasonic files in root canals.
• To compare the pressure wave characteristics generated by these different endodontic instruments.
• To evaluate the influence of laser power density on induced pressure waves.

Main Methods:

• 14 single-rooted teeth were prepared and filled with water.
• Pulsed Nd:YAG laser or sonic/ultrasonic files were activated within the canals.
• Pressure waves were detected using a piezoelectric transducer.
• Data analyzed via correlation coefficient and coefficient of variation.

Main Results:

• Nd:YAG laser generated pressure waves with amplitudes from 35.78 to 79.26 mV.
• Laser-induced wave amplitude positively correlated with power density (R² = 0.870).
• Sonic and ultrasonic vibrations produced mean amplitudes of 60.51 mV and 7.02 mV, respectively.

Conclusions:

• Nd:YAG laser irradiation induces unique pressure waves in root canals.
• These laser-induced waves differ significantly from those generated by sonic and ultrasonic instruments.
• The findings provide insights into the physical effects of laser use in endodontics.