Efecto de la radiación láser de baja energía en la velocidad del movimiento dentario y en los niveles de Rankl y OPG en pacientes con tratamiento ortodóncico

Resum

Objetive: to evaluate tooth movement, receptor activator of nuclear factor KB ligand (RANKL), osteoprotegerin (OPG) and RANKL/OPG ratio in gingival crevicular fluid (GCF) in compression side during initial orthodontic tooth treatment to determine the efficacy of low-level laser therapy (LLLT). Materials and methods: ten volunteers who required orthodontic treatment involving extraction of maxillary second premolars were selected. The orthodontic treatment was carried out by fixed multibracket appliances and Nance button as anchorage. For each patient, the upper first premolar of the quadrant 1 was chosen to be irradiated with a laser diode at 670 nm, 200 mW applied on the distal, buccal and lingual sides during 9 min on days 0, 1, 2, 3, 4 and 7. The same procedure was applied in the first premolar of the contralateral quadrant inserting the tip but without laser emission. Samples of GCF from the compression side of the upper first premolars to distalize were collected at baseline and after 2, 7, 30, 45 days post-treatment for determination of RANKL and OPG by enzymelinked immunosorbent assay (ELISA). In addition, tooth movement was assessed by scanning models. Results: there was improvement in the parameters studied (tooth movement, levels of RANKL in GCF and RANKL/OPG ratio) in the laser group when compared to the control group, although differences were not statistically significant. The accumulated retraction of the upper premolar at 30 days was higher in the laser group, and this difference was statistically significant between groups. Conclusions: LLLT delivered in repeated dosis (6 times in the initial 2 weeks) leads to a slight increase in the rate of closure of the spaces of extractions during orthodontic treatment.