Table 1.
Wavelengths of FLET and their biological effects.
| Visible light spectrum effects on biological targets | ||||
|---|---|---|---|---|
| Wavelength range | Visible light spectrum | Biological effect | Target | Main outcome |
| 660–780 nm | Yellow to Red | Decrease in fluid loss, tissue destruction and inflammation while increasing the deposition of collagen fibers, larger amounts of granulation tissue, less edema, a more vigorous inflammatory reaction and increased revascularization | Third-degree burns in rats | Inflammatory Modulation |
| 632.8-nm | Yellow to Orange | Significantly increases gene expression of TGF-β1, while significantly reducing inflammation in both nondiabetic and control rats leading to wound healing | Surgically tenotomized Achilles tendons in rats | Inflammatory Modulation |
| 660 and 880 nm | Red | Reduces the initial ulcer area by 13-fold versus control subjects | Patients with grade II pressure ulcers | Tissue proliferation and matrix deposition |
| 660 nm | Red | Full granulation and ulcer closure in 86% of the patients | Patients with recalcitrant venous ulcers due to chronic venous insufficiency syndrome | Tissue proliferation and matrix deposition |
| 633 or 830 nm | Yellow to Red | Cell migration, viability and proliferation | Skin fibroblasts in diabetic wounds | Tissue proliferation and matrix deposition |
| 633 nm | Yellow/Orange | Alleviating induced rat diabetic ulcers by an average of about 10%, although some diabetic ulcers can achieve 39% improvements | Diabetic ulcers | Tissue proliferation and matrix deposition |
| 632.8 | Red | Tissue healing by inducing a significant increase in dermal angiogenesis | Chronic radiation-induced dermatitis in breast cancer | Tissue proliferation and matrix deposition |
| 670 nm | Red | Human umbilical vein endothelial cell proliferation | Neoangiogenesis and wound healing | Neoangiogenesis and wound healing |
| 660 nm | Red | Increased secretion of the growth factors VEGF, basic FGF and HGF as well as increased neovascularization of the wound bed and regeneration of the skin than occurs in controls | Skin wound bed in athymic mice | Neoangiogenesis |
| 400–800 nm | Violet to Red (full range) | 62 and 83%, and 56% reduction in the colony count of E. coli, Streptococcus aureus and S. marcescens, respectively | Bacterial strains from clinical specimens | Antibacterial actions |
| 530 nm | Green | Inactivating bacteria such as S. mutans that is related to dental caries | Cariogenic bacteria | Antibacterial actions |
Created by the authors with the following references.
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