ABSTRACT
The effects of LED therapy at 940 nm on periodontal healing, inflammatory cell infiltration, and root resorption were analyzed in an experimental model of orthodontic tooth movement in rats. Twenty-five male Wistar rats were allocated into four experimental groups: Control animals (Co, n = 5), Controls + LED therapy (CoLED, n = 6), animals submitted to orthodontic force (RR, n = 7) and submitted to orthodontic force + LED therapy (RRLED, n = 7). All procedures were approved by the Committee for Ethics in Animal Experimentation of the Universidade Estadual de Londrina (protocol CEEA 5/2010 37359). A force of 50 g was applied to the right upper molars of RR and RRLED groups. On days 2, 3, and 4 after orthodontic treatment, the CoLED and RRLED groups received LED irradiation (940 nm, 4 J/cm(2)). The animals were killed on day 7 for histological analysis. An increased number of root resorption lacunae was found only in the RR group (p < 0.05). The RR group also presented more osteoclasts (p < 0.005) and inflammatory cell infiltration (p < 0.005) than the control group. The RRLED group presented fewer osteoclasts (p < 0.005) and inflammatory cells (p < 0.005) in the periodontal ligament than the RR group. The CoLED and RRLED groups presented more periodontal fibroblasts (p < 0.005) than non-irradiated groups. RRLED presented more blood vessels (p < 0.01) in the periodontal ligament than the RR group. In conclusion, the results suggest that LED therapy improved periodontal tissue repair and decreased inflammation and root resorption after the application of orthodontic force.
Subject(s)
Phototherapy/methods , Root Resorption/pathology , Root Resorption/therapy , Tooth Movement Techniques , Analysis of Variance , Animals , Inflammation , Male , Orthodontic Appliances , Rats , Rats, Wistar , Statistics, NonparametricABSTRACT
The aim of this work is to analyze the effects of LED therapy at 940 nm or cold water immersion therapy (CWI) after an acute bout of exercise on markers of muscle damage and inflammation. Thirty-two male Wistar rats were allocated into four groups: animals kept at rest (control), exercised animals (E), exercised + CWI (CWI), and exercised + LED therapy (LED). The animals swam for 100 min, after which blood samples were collected for lactate analysis. Animals in the E group were returned to their cages without treatment, the CWI group was placed in cold water (10°C) for 10 min and the LED group received LED irradiation on both gastrocnemius muscles (4 J/cm(2) each). After 24 h, the animals were killed and the soleus muscles were submitted to histological analysis. Blood samples were used for hematological and CK analyses. The results demonstrated that the LED group presented fewer areas of muscle damage and inflammatory cell infiltration and lower levels of CK activity than the E group. Fewer areas of damaged muscle fiber were observed in the LED group than in CWI. CWI and LED did not reduce edema areas. Hematological analysis showed no significant effect of either treatment on leukocyte counts. The results suggest that LED therapy is more efficient than CWI in preventing muscle damage and local inflammation after exercise.
Subject(s)
Cryotherapy/methods , Muscle, Skeletal/injuries , Phototherapy/methods , Animals , Creatine Kinase/metabolism , Immersion , Leukocytes/pathology , Male , Muscle, Skeletal/enzymology , Muscle, Skeletal/pathology , Physical Exertion , Rats , Rats, WistarABSTRACT
The objective of the present study was to evaluate the effect of 940 nm wavelength light emitting diode (LED) phototherapy on nerve regeneration in rats. Forty male Wistar rats weighing approximately 300 g each were divided into four groups: control (C); control submitted to LED phototherapy (CLed); Sciatic Nerve Lesion without LED phototherapy (L); Sciatic Nerve Lesion with LED phototherapy (LLed). The lesion was caused by crushing the right sciatic nerve. A dose of 4 J/cm(2) was used for ten consecutive days beginning on the first postoperative day. Groups C and L were submitted to the same procedure as the LLed group, but the equipment was turned off. The LED phototherapy with 940 nm wavelength reduced the areas of edema, the number of mononuclear cells present in the inflammatory infiltration, and increased functional recovery scores at 7, 14 and 21 days. The results suggest that the use of phototherapy at 940 nm after nerve damage improves morphofunctional recovery and nerve regeneration.
