The effectiveness of photobiomodulation in the management of temporomandibular pain sensitivity in rats: behavioral and neurochemical effects

Autor(es)

Rodrigues, Alex de Freitas ^{[1, 2]} ; Martins, Daniel de Oliveira ^[1] ; Chacur, Marucia ^[1] ; Luz, Joao Gualberto C. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biomed Sci, Dept Anat, Lab Funct Neuroanat Pain, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Dept Oral & Maxillofacial Surg, Sch Dent, Av Prof Linen Prestes 2227, Cidade Univ, BR-05508000 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Medical Science; v. 35, n. 2, p. 447-453, MAR 2020.
• Citações Web of Science: 0

Resumo

This study analyzed the effects of photobiomodulation (PBM) with low-level laser therapy on nociceptive behavior and neuronal activity in the trigeminal nucleus after experimental unilateral temporomandibular joint (TMJ) disc injury. The animals were divided into 4 groups (n = 10 each): group 1, surgical injury of the articular disc and PBM; group 2, sham-operated subjected to PBM; group 3, surgical injury of the articular disc; and group 4, control (Naive). Ten sessions of PBM were performed using GaAs laser with a wavelength of 904 nm, power of 75 W pico, average power of 0.043 W, area of the beam of 0.13 cm(2), duration of the pulses of 60 nseg (in the frequency of 9500 Hz), energy density of 5.95 J/cm(2), energy per point of 0.7 J, and power density of 333.8 mW/cm(2), and the irradiation was done for 18 s per point. Neuropathic symptoms were evaluated using the von Frey test. Trigeminal ganglion samples underwent immunoblotting to examine the expression of substance P, vanilloid transient potential receptor of subtype-1 (TRPV-1), and peptide related to the calcitonin gene (CGRP). There was a total decrease in pain sensitivity after the second session of PBM in operated animals, and this decrease remains until the last session. There was a significant decrease in the expression of SP, TRPV-1, and CGRP after PBM. Photobiomodulation therapy was effective in reducing nociceptive behavior and trigeminal nucleus neuronal activity after TMJ disc injury. (AU)

• Processo FAPESP: 17/05218-5 - Efeito da fotobioestimulação em diferentes neuropatias periférica em ratos.
• Beneficiário: Marucia Chacur
• Modalidade de apoio: Auxílio à Pesquisa - Regular