Digital photogrammetry and histomorphometric assessment of the effect of non-coherent light (light-emitting diode) therapy (λ640 ± 20 nm) on the repair of third-degree burns in rats

Abstract

Recent studies have demonstrated the efficacy of coherent light therapy from the red region of the electromagnetic spectrum on the tissue-healing process. This study analysed the effect of non-coherent light therapy (light-emitting diode-LED) with or without silver sulfadiazine (sulpha) on the healing process of third-degree burns. In this study, 72 rats with third-degree burns were randomly divided into six groups (n = 12): Gr1 (control), Gr2 (non-contact LED), Gr3 (contact LED), Gr4 (sulfadiazine), Gr5 (sulfadiazine + non-contact LED) and Gr6 (sulfadiazine + contact LED). The groups treated with LED therapy received treatment every 48 h (λ = 640 ± 20 nm, 110 mW, 16 J/cm(2); 41 s with contact and 680 s without contact). The digital photometric and histomorphometric analyses were conducted after the burn occurred. The combination of sulpha and LED (contact or non-contact) improved the healing of burn wounds. These results demonstrate that the combination of silver sulfadiazine with LED therapy (λ = 640 ± 20 nm, 4 J/cm(2), without contact) improves healing of third-degree burn wounds, significantly reduces the lesion area and increases the granulation tissue, increases the number of fibroblasts, promotes collagen synthesis and prevents burn infections by accelerating recovery.

Action of AlGaInP laser and high frequency generator in cutaneous wound healing. A comparative study

“…In this context, there is stimulation of the organism's defense and the beginning of the cicatrization, which consists in reconstructing the injured site, in order to restore the integrity and normal function 4 , besides being complex and dynamic, and involving biochemical and physiological events, which must act in harmony for the benefit of tissue restoration 5,6. However, the complex process of tissue cicatrization can be influenced, it may not occur in a successful manner and it has long been an object of study concerning the factors that affect it. In recent years, researchers have used different equipments to facilitate the healing process of skin wounds with demonstrably scientific results [7][8][9][10] . In this context, it refers to the low power laser (LPL), as AlGaInP, the AsGa and HeNe, therapeutic ultrasound,…”

Biomodulation effects of LED and therapeutic ultrasound combined with semipermeable dressing in the repair process of cutaneous lesions in rats

“…LED acts by direct intracellular stimulation based on NADH activation and oxidation and on the alteration of the mitochondrial redox potential, resulting in the so-called photobiostimulatory or photomodulatory effect. This action permits noninvasive wound treatment 7,8 .…”

Comparative Study of Morphometric and Fourier Transform Infrared Spectroscopy Analyses of the Collagen Fibers in the Repair Process of Cutaneous Lesions

“…Vibrational bands in the spectral ranges 7 A (3,600-3,000 cm The data obtained in this study enabled the observation that, through the analysis of the volume fraction of the collagenous fibers, the semipermeable dressing, ultrasonic irradiation, and phototherapy promote collagen synthesis, which confirms several experimental studies that have researched the individual effects of dressings, US, and LED therapy on the production of dermal collagen. 7,[12][13][14]21,25 At the experimental period of 7 days, none of the therapeutic protocols presented statistically significant qualitative or quantitative results, although there was a slight tendency in morphometric values for the group LED + D. It is worth emphasizing that during this stage, the process of tissue repair is at the end of the inflammatory phase, and the presence of inflammatory infiltrate is still visible. This result does not corroborate studies that suggest that phototherapy acts on cell permeability and mitochondria, by stimulating the synthesis of ATP and favoring the onset of the deposition of thin collagen fibrils.…”

“…Considering the data obtained at this experimental time for the LED group, this result is probably due to the action of phototherapy, making energy available to the cells that were damaged by the surgical process, thus accelerating the repair process during its secondary phase. 20,21,25,43,44 The most significant results were observed with the combination of LED and a semipermeable dressing (LED + D). It is noteworthy that the application of the dressing positively influenced the tissue repair process by accelerating it.…”

“…It was pulsed with a fundamental frequency of 3 MHz, had a power density of 0.5 W/cm 2 , a pulse repetition frequency of 16 Hz at 50%, an effective irradiation area of 3.5 cm, 2 and a 2-min application time in direct contact with circular motions. 7,21,25,26 The manufacturer calibrated the equipment before and after the experiment, ensuring that there was no loss of strength during the treatment of the experimental groups.…”