Open AccessEffect of 670 nm laser photobiomodulation on vascular density and fibroplasia in late stages of tissue repair
Author(s) -
Fortuna Tila,
Gonzalez Ana Cristina,
Sá Maíra F,
Andrade Zilton de A,
Reis Sílvia R A,
Medrado Alena R A P
Publication year - 2018
Publication title -
international wound journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.867
H-Index - 63
eISSN - 1742-481X
pISSN - 1742-4801
DOI - 10.1111/iwj.12861
Subject(s) - haematoxylin , medicine , cd31 , sirius red , wound healing , statistical significance , immunohistochemistry , eosin , pathology , statistical analysis , staining , urology , surgery , statistics , mathematics
This study aimed to investigate the effects of gallium‐aluminum‐arsenium (GaAlAs) (670 nm) laser therapy on neoangiogenesis and fibroplasia during tissue remodelling. Forty male Wistar rats underwent cutaneous surgery and were divided into 2 experimental groups: the Control and Laser group (9 mW, 670 nm, 0.031 W/cm 2 , 4 J/cm 2 ). After 14, 21, 28, and 35 days, the animals were euthanised. Descriptive and quantitative analyses were performed in sections stained with haematoxylin‐eosin and Sirius Red, respectively. The amounts of VEGF+ and CD31+ cells were evaluated by immunohistochemistry and histomorphometric analysis, respectively. Statistical analysis was performed using the Mann‐Whitney, Friedman, and Spearman correlation test, P < 0.05. The collagen expression was significantly higher in the laser group compared with the control group on days 14 and 21 after the creation of the skin wound ( P = 0.008; P = 0.016) and in the control group between 14 and 28 and 14 and 35 days ( P = 0.001; P = 0.007). There were more blood vessels in three periods of the study only in the (Laser) treated group, with statistical significance at day 14 ( P = 0.016). There was no statistically significant difference in VEGF+ cell count in the different experimental groups throughout the study, although a positive correlation was shown with the area of collagen on days 14 and 28 ( P = 0.037). Laser treatment had a positive effect in the late course of healing, particularly with regards to collagen expression and the number of newly formed vessels. VEGF+ cells were present in both experimental groups, and VEGF appeared to influence fibroplasia in the treated group.