Semiconductor laser irradiation improves root canal sealing during routine root canal therapy

Area of Science:

• Endodontics
• Dental Materials Science
• Biomedical Engineering

Background:

• Root canal therapy (RCT) aims to seal the root canal system to prevent reinfection.
• Achieving optimal apical sealing is crucial for the long-term success of RCT.
• Current methods for canal cleaning and disinfection may leave imperfections affecting seal quality.

Purpose of the Study:

• To evaluate the efficacy of semiconductor laser irradiation in improving root canal sealing post-RCT.
• To compare the effects of laser irradiation with ultrasonic irrigation on apical sealing.
• To investigate the micro-structural changes induced by laser treatment in dentinal tubules.

Main Methods:

• Sixty single-rooted human teeth underwent conventional RCT.
• Teeth were divided into groups: semiconductor laser irradiation, ultrasonic irrigation (positive control), and no treatment (negative control).
• Apical microleakage was measured, and root canal micro-structures were examined using scanning electron microscopy (SEM).

Main Results:

• Both laser irradiation and ultrasonic irrigation significantly improved apical sealing compared to the control group (p<0.5).
• No significant difference in sealing was observed between the laser and ultrasonic groups (p>0.5).
• SEM revealed melted, narrowed, or closed dentinal tubules in the laser group, while the ultrasonic group showed tubules filled with debris.

Conclusions:

• Semiconductor laser application prior to root canal obturation enhances apical sealing.
• Laser irradiation offers a viable alternative or adjunct to ultrasonic irrigation for improving root canal seal quality.
• The mechanism involves physical modification of dentinal tubules by laser energy.