Thermal Effects on Dental Pulp during Laser-Assisted Bleaching Procedures with Diode Lasers in a Clinical Study

Area of Science:

• Dental materials science
• Laser dentistry
• Biomedical engineering

Background:

• Tooth bleaching commonly utilizes lasers, posing risks of pulpal damage.
• Pulpal temperature increases of 5.6 °C or higher can lead to tooth death.
• Investigating laser parameters is crucial for safe bleaching procedures.

Purpose of the Study:

• To determine pulpal temperature increases during laser bleaching with varying parameters.
• To compare temperature measurements using thermocouples and thermal cameras.
• To identify safe laser settings to maintain pulpal temperature below critical thresholds.

Main Methods:

• Human extracted teeth were used for bleaching experiments.
• Teeth underwent conventional and laser bleaching (940 nm, 445 nm, 970 nm).
• Pulpal temperature was recorded using thermocouples and thermal cameras in different setups.

Main Results:

• Safe temperature increases (<5.6 °C) were observed at specific low power settings for 940 nm, 445 nm, and 970 nm lasers.
• Higher power settings for all tested lasers resulted in temperature increases ≥5.6 °C.
• Thermocouple and thermal camera measurements showed a mean difference of approximately 2.3 °C.

Conclusions:

• Laser type, power, and exposure time are critical factors in preventing pulpal overheating during bleaching.
• Specific low-power settings for 940 nm, 445 nm, and 970 nm lasers can achieve bleaching without exceeding the critical temperature threshold.
• Careful parameter selection is essential for safe and effective laser-assisted tooth bleaching.