Effect of equal daily doses achieved by different power densities of low-level laser therapy at 635 nm on open skin wound healing in normal and corticosteroid-treated rats

Abstract

Optimal parameters of low-level laser therapy (LLLT) for wound healing are still discussed. Hence, our study was aimed to compare effects of different power densities of LLLT at 635 nm in rats. Four, round, full-thickness, skin wounds were made on the backs of 48 rats that were divided into two groups (non-steroid laser-treated and steroid laser-treated). Three wounds were stimulated daily with a diode laser (daily dose 5 J/cm(2)) each with different power density (1 mW/cm(2), 5 mW/cm(2), and 15 mW/cm(2)), whereas the fourth wound served as a control. Two days, 6 days, and 14 days after surgery, eight animals from each group were killed and samples were removed for histological evaluation. In the non-steroid laser-treated rats, significant acceleration of epithelization and collagen synthesis 2 days and 6 days after surgery was observed in stimulated wounds. In steroid laser-treated rats, 2 days and 14 days after surgery, a decreased leucocyte/macrophage ratio and a reduction in the area of granulation tissue were recorded, respectively. In conclusion, LLLT, by the method we used, improved wound healing in the non-steroid laser-treated rats, but it was useless after corticosteroid treatment.

Low-Level Laser Therapy with 810 nm Wavelength Improves Skin Wound Healing in Rats with Streptozotocin-Induced Diabetes

“…20 To determine the effect of LLLT on GT formation, the area of GT in sections (sections were made from the middle of the wound) made from all animals was measured by means of QuickPHOTO MICRO 2.2 (Promicra, Prague, Czech Republic) software as previously reported. 9 …”

“…However, it has already been shown that LLLT can reduce pain, [5][6][7][8] and affect all three basic phases (i.e., inflammation, proliferation, and maturation) of wound healing. [9][10][11] In addition, positive LLLT effects have been observed in terms of increased wound tensile strength (TS), 12,13 and/or improved microcirculation. 14 It has previously been shown that several different wavelengths of laser radiation, such as 633, 670, and 820 nm, can facilitate oxidizing of cytochrome c oxidase.…”

“…9,10,13 Wound TS measurement and histology have been shown in numerous experimental studies to be appropriate examination techniques for wound healing; therefore, we decided to use these outcomes to evaluate the effects of LLLT on skin repair in diabetic rats using two basic wound healing models (incisional and excisional). 18 …”

“…In several previously published studies it has been shown that LLLT with selected parameters may improve wound healing in normal and impaired conditions. [9][10][11][12] As optimal LLLT parameters of infrared lasers are still unknown, we decided to investigate if wound healing could be modulated after laser irradiation with the commonly used wavelength of 810 nm.…”

Superpulsed laser therapy on healing process after tooth extraction in patients waiting for liver transplantation

“…It has been shown to produce several different effects, including pain relief, wound healing and nerve regeneration. It has potential antimicrobial and biostimulating effects when applied to oral tissues, for example improving wound healing, enhancing epithelization after periodontal surgery, minimizing oedema after third-molar surgery, and preventing oral mucositis [25][26][27][28][29][30].…”