Evaluation and comparison of the effectiveness of low-level laser therapy and low-intensity pulsed ultrasound in reducing orthodontic pain

According to a recent study, low-level laser therapy (LLLT) and low-intensity pulsed ultrasound (LIPUS) effectively reduced separation pain when applied in multiple doses during orthodontic treatment. The results of this study were published in the journal, BMC Oral Health.

150 patients were randomly assigned to three groups in this single-blind, randomized controlled trial: the LLLT group, the LIPUS group, and the control group. The first dose of the laser or ultrasound was applied 5 min from the separators' placement, second dose was given after 24 h, and the last dose was administered on both maxillary and mandibular first molars after 48 h. The patients were exposed to the laser for 20 s, using an 810-nm aluminum-gallium-arsenide (AlGaAs) diode laser on continuous mode. For 20 minutes, 1.6 MHz ultrasonic toothbrush treatment was applied (5 minutes for each first molar). The control group was administered the separator without any other intervention. Pain intensity was assessed at several time intervals during the first four days post the separator’s placement, using a Visual Analog Scale (VAS 100 mm).

It was found after assessing 145 patients that a significant difference in pain perception was observed among the three groups after 5 min. Pain level reached its maximum intensity after 24 h. All the assessment time points showed a statistically significant decrease in pain scores for both the laser and the ultrasound groups when compared to the control group. Moreover, the laser and ultrasound group showed no difference between them in terms of reducing the pain scores.

Hence, it can be concluded that LLLT and the LIPUS may effectively reduce the separation pain experienced during orthodontic treatment after the application of multiple doses, without any difference between them.