Temperature elevation during root canal treatment with a 445-nm diode laser—an in vitro study

Abstract

Objective This study investigated the thermal effects of a 445-nm diode laser on tooth roots of endodontic treatment. Material and methods A total of 15 human single-rooted extracted teeth were included in the survey. Samples were sectioned at the cementoenamel junction. The root canals were instrumented using a rotary system. Each root was fitted into a resin mold and was fixed in a vertical position using clamps. All samples were placed on a support in a thermal path at 37°C. The root canals were randomly divided into three groups (n = 5 each): samples were irradiated with 0.6 W continuous wave (CW), 0.4 W CW, and 1.2 W gated mode, at a repetition rate of 10 Hz with a pulse duration of 50 ms. The time-dependent temperature elevations of the cervical, middle, and apical thirds of the roots were recorded at a sampling rate of 2 Hz during laser irradiation with a K-type thermocouple measurement system. Results The mean temperature rise inside the roots in this study was below 10°C, whereas the maximum temperature rise of 9.83°C (0.6 W CW) and 9.81°C (1.2 W gated mode, repetition rate 10 Hz, and pulse duration 50 ms) was registered in lower incisors, and 4.97°C was detected at 0.4 W CW. The thermal changes seen in the apical thirds of the root were statically significantly (p < 0.001) and were greater than those at the coronal and middle thirds. Conclusion The results of this study suggest that 445-nm diode lasers may provide a safe temperature for endodontic applications.

Antibacterial Effects of the Novel Blue Laser and Erbium Chromium Laser on Enterococcus Faecalis in Root Canal Dentin with Different Thicknesses

“…Recent studies have shown the effects of laser in canal disinfection. Among the types of lasers, diode lasers have been widely used in dentistry due to their small sizes, low prices, and easy operations [11][12][13]. Diode lasers have little interference with water and hydroxyapatite due to their flexible fibers, which can easily penetrate into curved canals [14].…”

The blue wavelengths in laser dentistry: a review of current literature

“…Alshamiri et al tested the temperature increase on teeth roots during laser-assisted endodontic treatment with a 445-nm diode laser. Although the sample of single-rooted teeth used was low (n=15), the authors concluded that under their specific protocol all tested power settings (0.6 W CW, 0.4 W CW, 1.2 W peak, 10 Hz, 50-ms pulse duration, and 50% duty cycle) were found safe for the surrounding tissues as none exceeded the 10 o C threshold [5].…”