Evaluation of the use of photobiomodulation following the placement of elastomeric separators: Protocol for a randomized controlled clinical trial

BACKGROUND: Pain stemming from the placement of elastomeric separators and the exchanging of wires and accessories is the greatest reason for abandoning orthodontic treatment. Indeed, discomfort related to treatment exerts a negative impact on quality of life due to the difficulty chewing and biting. This paper proposes a study to evaluate the analgesic effects of photomiobodulation (PBM) on individuals undergoing orthodontic treatment. METHODS: The sample will be composed of 72 individuals who receiving elastomeric separators on the mesial and distal faces of the maxillary first molars. The patients will be randomly allocated to 2 groups: an experimental group irradiated with low-level laser and a sham group submitted to simulated laser irradiation. Upon the placement of the separators, the experimental group will receive a single application of PBM on the mesial and distal cervical portion and apical third of the molars. Perceived pain will be analyzed after one hour using the visual analog scale in both groups. Samples will be taken of the gingival crevice with absorbent paper for 30 seconds for the analysis of cytokines using ELISA and the results of the 2 groups will be compared. The patients will sign a statement of informed consent. Statistical analysis will be performed with the Student's t test and analysis of variance (ANOVA). DISCUSSION: The expectation is that the patients in the irradiated group will have a lower perception of pain and lower quantity of cytokines compared to those in the sham group. The purpose of the study is to establish an effective method for PBM with the use of low-level infrared laser (Ga-Al-As with a wavelength of 808 nm and output power of 100 mW) for reductions in pain and inflammatory cytokines related to orthodontic treatment. TRIAL REGISTRATION: This protocol was registered in ClinicalTrial.gov, under number NCT03939988. It was first posted and last updated in May 6, 2019.