Histomorphometric evaluation of skin wounds in rats submitted to biomodulatory therapies – research protocol





Wound healing, Low-Level Light Therapy, Ozone, Rats, Wistar


INTRODUCTION: The use of biomodulatory therapies in order to help tissue repair has been increasingly common in different areas of health. OBJECTIVE: This study aims to comparatively evaluate the effects of 660 nm laser photobiomodulation, ozone therapy, and ozonated oil on repair through histomorphometric analysis in skin wounds in rats. Forty Wistar rats will be divided into 4 groups of 10 animals each, Control Group (GC), Laser Group (LG), Ozone Gas Group (OGG), and Ozonated Oil Group (OOG). MATERIALS AND METHODS: Standard skin wounds will be made on the back of the animals, and the different experimental groups will be treated with the biomodulatory therapies described for three consecutive days. Five and ten days after surgery, five rats from each group will be euthanized. Skin fragments, including the wound area, will be removed for histological processing and subsequent staining of histological sections with Hematoxylin-eosin and Sirius red. Micrographs of the histological sections will be obtained and ten standard images will be captured for quantitative evaluation of the variables collagen area, number of blood vessels, and epithelium thickness. The variables infiltrate of polymorphonuclear and monomorphonuclear inflammatory cells, as well as edema, will be analyzed semiquantitatively. Statistical analysis of the study variables will be performed, with a significance level of p<0.05. CONCLUSION: It is expected to verify which of the biomodulatory therapies used can favor the resolution of tissue repair, in particular, by promoting collagen biosynthesis.


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Histomorphometric evaluation of skin wounds in rats submitted to biomodulatory therapies – research protocol. (2023). Journal of Evidence-Based Healthcare, 5, e4105. https://doi.org/10.17267/2675-021Xevidence.2023.e4105

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