Increased Amount of Blood Vessels after Blue-light-emitting Diode Exposure During Orthodontic Tooth Movement in Rats

Orthodontic tooth movement (OTM) results from a biological response that facilitates tooth movement. Light-emitting diode (LED) can produce a variety of beneficial biological effects. Angiogenesis plays an important role in bone remodeling; hence, the amount of blood vessels can be used as a benchmark in OTM. The objective of this study is to analyze the effects of blue LED on the amount of blood vessels visible on the tension and pressure side during OTM. This study included 48 Wistar rats that were divided into 4 groups: control group; the treatment group exposed to blue LED light for 25 seconds (T1); the treatment group exposed to blue LED light for 30 seconds (T2); and the treatment group exposed to blue LED light for 35 seconds (T3) (n = 12). An open coil spring placed on the mandibular incisors generated the orthodontic force. The amount of blood vessels present on the pressure and tension sides of the periodontal tissue was observed on histological specimens with hematoxylin–eosin staining on days 0, 3, 7, and 14 at 400× magnification. The obtained data were analyzed using two-way ANOVA followed by the post-hoc least significant different (LSD) test (P < 0.05). The amount of blood vessels on the tension and pressure sides in the T3 treatment group was higher than the other groups (P < 0.05). We conclude that exposure to blue LED increased the amount of blood vessels during OTM on the tension and pressure sides in rats.